JP4722785B2 - Wireless signal separation method, wireless receiver, program, and recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wireless signal separation method whereby a wireless communication apparatus for executing wireless communication by a MIMO system can be downsized, weight-reduced, and a processing delay and a consumed electric energy can be reduced. <P>SOLUTION: The wireless signal separation method determines the order of detection of respective signals of T sets of elements in a transmission signal vector s of a signal transmitted from a wireless transmission apparatus, and rearranges row vectors and column vectors of a matrix G calculated by an equation of G=H<SP>H</SP>H+&alpha;<SP>2</SP>using column vectors of a propagation path matrix H, the propagation path matrix H, a coefficient &alpha;, and a unit matrix I according to a sequence list S. The method derives a triangle matrix R from a matrix resulting from rearranging the matrix G, and generates a matrix Q by applying orthogonal processing to a matrix resulting from rearranging the column vectors of the propagation path matrix H by using the triangle matrix. Moreover, the method filters a received vector x by using a complex conjugate transposition of the matrix Q, sequentially detects the T sets of transmission signals by using the triangle matrix R, rearranges T sets of the detected transmission signals into signals with the originally transmitted spacial sequence, and outputs the resulting transmission signals. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention wirelessly transmits a plurality of signal sequences on the same frequency using a MIMO (Multiple Input Multiple Output) channel and performs signal detection (or signal separation) on a spatially multiplexed signal in a wireless receiver. In particular, a radio signal separation method, a radio reception apparatus, and a program using a MIMO-OFDN communication system, which is a combination of an OFDM (Orthogonal frequency division multiplex) modulation system that is a multicarrier modulation system and a MIMO communication system, and a communication system The present invention relates to a recording medium.

  In wireless communication systems, it is essential to improve frequency utilization efficiency in order to increase the amount of communication transmission using limited frequency resources. As a technique for improving the frequency utilization efficiency, a plurality of transmission antennas are provided on the wireless transmission device side of the wireless communication system, a plurality of reception antennas are provided on the wireless reception device side, and spatial multiplexing channels are provided on the same frequency band at the same time. There has been proposed a MIMO system configured to improve the information transmission rate.

  In addition, there is an OFDM multicarrier modulation scheme (hereinafter referred to as an OFDM scheme) in which an information signal is transmitted on a plurality of subcarriers orthogonal to each other. The OFDM scheme is a modulation scheme capable of flattening frequency selective fading by narrowing the band of each subcarrier, and further by multipath fading by adding a guard interval. The influence of intersymbol interference can be reduced. Accordingly, the OFDM system is widely used in wireless communication and broadcasting systems such as wireless LAN (Local Area Network) and digital television broadcasting.

A combination of the above MIMO system and the OFDM scheme is called a MIMO-OFDM system. In contrast, when a single carrier modulation scheme is simply used, it is called a MIMO-Single system. Both are unified and called a MIMO system.
A comparison of detection algorithms including BLAST for wireless communication using multiple antennas ”, Hassell, CZW; Thompson, JS; Mulgrew, B .; Grant, PM;, Personal, Indoor and Mobile Radio Communications, 2000. PIMRC 2000. The 11th IEEE International Symposium on Volume 1, 18-21 Sept. 2000 Page (s): 698-703 vol.1

By the way, in the signal detector (Signal Detector) with which the conventional radio | wireless receiver was equipped, as a signal detection method, ZF (Zero-Forcing) system, MMSE (Minimum Mean Square Error) system, SIC (Successive Interference Cancellation) system, MLD A combination of the (Maximum Likelihood Detection) method and those basic methods is used. Among these, the SIC method is excellent from the viewpoint of achieving both the reception error rate characteristics and the amount of computation required for signal detection processing. Therefore, the SIC method is considered to be a very practical approach for realizing MIMO transmission. The SIC scheme is compared with other signal detection process, rather than simultaneously, it is a process characterized to sequentially detect the T transmitted signals s _t. Here, there are two types of SIC methods: ZF standards and MMSE standards. A representative example of the ZF-SIC (ZF-based SIC method) method is a V-BLAST (Vertical Bell Laboratories Layered Space-Time) method. An MMSE-SIC (MMSE standard SIC method) has also been proposed. This method has the same required calculation amount as the ZF-SIC method, but has better error rate characteristics (that is, reception quality). It is a feature. Hereinafter, a conventional MMSE-SIC method will be described.

If the input to the signal detection device is the propagation path matrix H and a and the received signal vector x, and the signal output through the signal detection processing by the MMSE-SIC method is the detection signal ^ s, the signal detection device
<a> For the T elements s = [s ₁ , s ₂ ,..., S _T ] in the transmission signal vector s, it has the maximum post-detection SNR (Signal to Interference plus noise ratio). Next, a transmission signal in the transmission system is determined as a signal detection target.
<B> An extraction vector based on a minimum mean square error (MMSE) for detecting the detection signal determined in a is calculated.
Element signals in the order determined in a are detected in s = [s ₁ , s ₂ ,..., S _T ] using the extraction vector generated in <c> b.
<D> Update the reception vector x and the propagation path matrix H.
Then, the signal detection apparatus repeatedly executes T times for all processes a to d.

Here, when the MMSE-SIC method, which is a conventional SIC method, is applied to process a spatially multiplexed signal in a MIMO system in a signal detection device of a wireless reception device, the following problems exist.
<Problem 1> The processing computation amount is enormous and the required computation circuit scale becomes large (T pseudo-inverse matrix computation is required, and the computation requirement amount becomes large as O (T ⁴ ). (In a MIMO system, the required amount of computation is enormous.)
<Problem 2> Increased required storage device capacity (Pseudo inverse matrix calculation requires a large storage capacity. Also, a storage device is required for updating the propagation path matrix H and storing the extracted vector)
<Problem 3> It is difficult to reduce the size and weight (in a wireless transmission device, particularly a wireless portable terminal, it is desirable to reduce the size and weight, but in the conventional MMSE-SIC method, the required arithmetic circuit scale and memory are required. (Since the device is large, it becomes difficult to reduce the size and weight of the wireless transmitter)
<Problem 4> Processing delay increases (the processing delay is large because T times of pseudo inverse matrix operations cannot be parallelized. In particular, when the number of transmission antennas is large, the number of pseudo inverse matrix operations is large. In order to solve this problem, there is a way to increase the operating clock frequency in the arithmetic circuit, which leads to a dramatic increase in power consumption)
<Problem 5> Large required power consumption (Since the required power is proportional to the required arithmetic circuit scale and its operation clock frequency, it is considered that the conventional MMSE-SIC system consumes a large amount of power. It is difficult to secure sufficient operating time for the MIMO system)
<Problem 6> Not suitable for mass production of products (Based on the above-mentioned problems 1 to 5, it is extremely difficult to mount the conventional MMSE-SIC method on a wireless receiver. That is, the conventional MMSE-SIC method is mounted. The manufacturing cost of the wireless device equipped with the MIMO system is high and is not suitable for mass production)

  Accordingly, the present invention reduces the amount of processing computation and the required computation circuit scale, thereby reducing the size and weight of a wireless communication device that performs wireless communication using a MIMO system, and reducing the processing delay and power consumption of the wireless communication device. It is an object of the present invention to provide a radio signal separation method, a radio reception device, a program, and a recording medium that can provide a radio communication device suitable for mass production.

In order to achieve the above object, the present invention provides a wireless reception apparatus for detecting a received signal using a propagation path matrix H, a predetermined coefficient α, and a received signal vector x in a MIMO (Multiple Input Multiple Output) system. A signal separation method for receiving power calculated from the propagation path matrix H for each of the T elements in the transmission signal vector s of the signal transmitted by the wireless transmission device. And is recorded in the order list, and G = H ^H H + α ² I using the complex conjugate transpose of the channel matrix H and the channel matrix H, the coefficient α, and the unit matrix I. The row vector and the column vector of the matrix G calculated from the above are rearranged according to the order list S, the triangular matrix R is derived from the matrix obtained by rearranging the matrix G, and the column vector of the channel matrix H is rearranged. The obtained matrix to generate a matrix Q by orthogonal by using the triangular matrix, and filtering the received vector x by using the complex conjugate transpose of the matrix Q, which is filtered using the triangular matrix R received Performs backward substitution processing or forward substitution processing on the vector, and repeats the processing of performing a hard decision on the received signal one by one in the order of signal detection and the processing of removing the interference component to other received signals by the hard-decision received signal Thus, the T transmission signals are sequentially detected, and the detected T transmission signals are rearranged in the original transmitted spatial order according to the order list and output. It is.

The present invention also provides a radio signal separation method in a radio reception apparatus that performs signal detection of a received signal using a propagation path matrix H, a predetermined coefficient α, and a received signal vector x in a MIMO (Multiple Input Multiple Output) system, For T elements in the transmission signal vector s of the signal transmitted by the wireless transmission device, the order of signal detection is determined by the correlation between the received power calculated from the propagation path matrix H and the propagation path. G = H ^H H + α ² I using the detection order determination process for determining simultaneously and recording in the order list, the complex conjugate transposition of the propagation path matrix H, the propagation path matrix H, the coefficient α, and the unit matrix I A rearrangement process for rearranging the calculated row vector and column vector of the matrix G according to the order list S; an upper triangular matrix R is derived from the rearranged matrix G; A matrix R / matrix Q generation process for generating a matrix Q by orthogonalizing a matrix in which column vectors of H are rearranged using the upper triangular matrix R, and a reception vector using a complex conjugate transpose of the matrix Q The filtering process for filtering x, the filtering result and the upper triangular structure of the upper triangular matrix R are used to perform a backward substitution process on the filtered received vector, and the received signals one by one in the order of the signal detection. A reverse substitution process for sequentially detecting the T transmission signals by repeating a process for performing a hard decision and a process for removing an interference component from another received signal by the received signal subjected to the hard decision, and the detected T pieces A rearrangement process for rearranging the transmission signals in the original order according to the order list and outputting the rearranged signals in the original spatial order. It is away method.

Further, the present invention is the above-described wireless signal separation method, wherein the detection order determination process generates the order list according to the matrix G and an order list generation formula, and the rearrangement process arranges the propagation path matrix H. A matrix H ′ as a result of replacement and a matrix G ′ as a result of rearranging the matrix G are output, and the matrix R / matrix Q generation processing uses the triangular matrix calculation formula from the matrix G ′ as an upper triangle. A matrix R is derived, the matrix H ′ is orthogonalized using the upper triangular matrix R to generate and output a matrix Q, and the filtering processing includes the complex conjugate transpose of the matrix Q and the received signal vector x. The vector y is calculated by multiplication, and the backward substitution process calculates the detected transmission signal vector by the backward substitution calculation process using the column vector y and the upper triangular matrix R, and the detected transmission signal vector T Pieces The elements are detected in order, the interference component is calculated according to the interference component calculation formula, the soft decision detection signal is calculated by subtracting the interference component from the _kth element y _{k of the} column vector y, and the soft decision detection A hard decision is performed on the signal based on the constellation applied at the time of modulation on the transmission side, a hard decision detection signal is calculated, and the order rearrangement process is performed by using the detected transmission signal vector obtained by the backward substitution process. After rearranging according to the order list, the rearrangement result is output.

Also, in the radio signal separation method according to the present invention, the detection order determination processing decomposes the matrix G to derive an upper triangular matrix, and calculates an l-order norm in the p-th row of the inverse matrix U of the upper triangular matrix. and multiply d _l calculates beta _p, rearranges the values of the beta _p calculated for an inverse matrix U of the upper triangular matrix in ascending order, to generate the numerical values obtained in the rearrangement as ordered list, said arrangement The replacement process outputs a matrix H ′ as a result of rearranging the propagation path matrix H and a matrix G ′ as a result of the rearrangement of the matrix G, and the matrix R / matrix Q generation process includes the matrix G ′ An upper triangular matrix R is derived from 'using a triangular matrix calculation formula, and the matrix H' is orthogonalized using the upper triangular matrix R to generate and output a matrix Q. The filtering process Multiplying the complex conjugate transpose and the received signal vector x The backward substitution process calculates a detected transmission signal vector by backward substitution arithmetic processing using the column vector y and the upper triangular matrix R, and T elements of the detected transmission signal vector are calculated. Are sequentially detected, an interference component is calculated according to an interference component calculation formula, a soft decision detection signal is calculated by subtracting the interference component from the k th element y _{k of the} column vector y, and the soft decision detection signal On the other hand, a hard decision is performed based on the constellation applied at the time of modulation on the transmission side to calculate a hard decision detection signal, and the order rearrangement process uses the detected transmission signal vector obtained by the backward substitution process as the After sorting according to the order list, the sorting result is output.

The present invention also provides a radio signal separation method in a radio reception apparatus that performs signal detection of a received signal using a propagation path matrix H, a predetermined coefficient α, and a received signal vector x in a MIMO (Multiple Input Multiple Output) system, For T elements in the transmission signal vector s of the signal transmitted by the wireless transmission device, the order of signal detection is determined by the correlation between the received power calculated from the propagation path matrix H and the propagation path. G = H ^H H + α ² I using the detection order determination process for determining simultaneously and recording in the order list, the complex conjugate transposition of the propagation path matrix H, the propagation path matrix H, the coefficient α, and the unit matrix I A rearrangement process for rearranging the calculated row vector and column vector of the matrix G according to the order list S; a lower triangular matrix R is derived from the rearranged matrix G; A matrix R / matrix Q generation process for generating a matrix Q by orthogonalizing a matrix in which column vectors of H are rearranged using the lower triangular matrix R, and a reception vector using a complex conjugate transpose of the matrix Q Using the filtering process for filtering x, the filtering result, and the lower triangular structure of the lower triangular matrix R , a forward substitution process is performed on the filtered received vector, and the received signal is received one by one in the order of the signal detection. A forward substitution process for sequentially detecting the T transmission signals by repeating a process for performing a hard decision and a process for removing an interference component from another received signal by a hard-decision received signal, and the detected T pieces A rearrangement process for rearranging the transmission signals in the original order according to the order list and outputting the rearranged signals in the original spatial order. It is away method.

Further, the present invention is the above-described wireless signal separation method, wherein the detection order determination process generates the order list according to the matrix G and an order list generation formula, and the rearrangement process arranges the propagation path matrix H. A matrix H ′ as a result of replacement and a matrix G ′ as a result of rearranging the matrix G are output, and the matrix R / matrix Q generation processing uses the triangular matrix calculation formula from the matrix G ′ as a lower triangle. A matrix R is derived, and the matrix H ′ is orthogonalized by using the lower triangular matrix R to generate and output a matrix Q. The filtering processing includes a complex conjugate transpose of the matrix Q and the received signal vector x. A vector y is calculated by multiplication, and the forward substitution process calculates a detected transmission signal vector by a forward substitution calculation process using the column vector y and the lower triangular matrix R, and the detected transmission signal vector T Pieces The elements are detected in order, the interference component is calculated according to the interference component calculation formula, the soft decision detection signal is calculated by subtracting the interference component from the _kth element y _{k of the} column vector y, and the soft decision detection A hard decision is performed on the signal based on the constellation applied at the time of modulation on the transmission side to calculate a hard decision detection signal, and the order rearrangement process uses the detected transmission signal vector obtained by the forward substitution process. After rearranging according to the order list, the rearrangement result is output.

Also, in the radio signal separation method according to the present invention, the detection order determination process decomposes the matrix G to derive a lower triangular matrix, and calculates an l-order norm in the p-th row of the inverse matrix U of the lower triangular matrix. and multiply d _l calculates beta _p, rearranges the values of the beta _p calculated for an inverse matrix U of the lower triangular matrix in ascending order, to generate the numerical values obtained in the rearrangement as ordered list, said arrangement The replacement process outputs a matrix H ′ as a result of rearranging the propagation path matrix H and a matrix G ′ as a result of the rearrangement of the matrix G, and the matrix R / matrix Q generation process includes the matrix G ′ A lower triangular matrix R is derived from 'using a triangular matrix calculation formula, and the matrix H' is orthogonalized using the lower triangular matrix R to generate and output a matrix Q. The filtering process Multiplying the complex conjugate transpose and the received signal vector x The forward substitution process calculates a detected transmission signal vector by a forward substitution calculation process using the column vector y and the lower triangular matrix R, and T elements of the detected transmission signal vector are calculated. Are sequentially detected, an interference component is calculated according to an interference component calculation formula, a soft decision detection signal is calculated by subtracting the interference component from the k th element y _{k of the} column vector y, and the soft decision detection signal On the other hand, a hard decision is performed based on the constellation applied at the time of modulation on the transmission side, a hard decision detection signal is calculated, and the order rearrangement process uses the detected transmission signal vector obtained by the forward substitution process as described above. After sorting according to the order list, the sorting result is output.

The present invention also relates to a radio reception apparatus that performs signal detection of a received signal using a propagation path matrix H, a predetermined coefficient α, and a received signal vector x in a MIMO (Multiple Input Multiple Output) system, and the transmission of the radio transmission apparatus For the T elements in the transmission signal vector s of the transmitted signal, the order of signal detection is determined by the correlation between the received power calculated from the propagation path matrix H and the propagation path , and the order list A row vector and column of the matrix G calculated from G = H ^H H + α ² I using the complex conjugate transpose of the channel matrix H, the channel matrix H, the coefficient α, and the unit matrix I Means for rearranging vectors in accordance with the order list S; and a triangular matrix R is derived from the matrix obtained by rearranging the matrix G, and a matrix in which the column vectors of the propagation path matrix H are rearranged is used as the triangular matrix. Means for generating the matrix Q by orthogonalizing, means for filtering the received vector x using the complex conjugate transpose of the matrix Q, and backward substitution processing for the received vector filtered using the triangular matrix R, or By performing forward substitution processing and repeating the processing of performing a hard decision on the received signal one by one in the order of the signal detection and the processing of removing the interference component to other received signals by the hard-decision received signal, the T pieces And a means for rearranging the detected T transmission signals in the order of the original transmitted spatial order according to the order list and outputting them. It is.

The present invention also relates to a radio reception apparatus that performs signal detection of a received signal using a propagation path matrix H, a predetermined coefficient α, and a received signal vector x in a MIMO (Multiple Input Multiple Output) system, and the transmission of the radio transmission apparatus For the T elements in the transmitted signal vector s of the transmitted signal, the order of signal detection is simultaneously determined by the received power calculated from the propagation path matrix H and the correlation between the propagation paths. The matrix G calculated from G = H ^H H + α ² I using the detection order determining means to be recorded in the list, the complex conjugate transpose of the channel matrix H, the channel matrix H, the coefficient α, and the unit matrix I Rearrangement means for rearranging row vectors and column vectors according to the order list S; an upper triangular matrix R is derived from the matrix obtained by rearranging the matrix G, and the column vector of the propagation path matrix H is rearranged. Matrix R / matrix Q generating means for generating a matrix Q by orthogonalizing the obtained matrix using the upper triangular matrix R, and filtering means for filtering a received vector x using a complex conjugate transpose of the matrix Q; Using the filtering result and the upper triangular structure of the upper triangular matrix R , a backward substitution process is performed on the filtered received vector to perform a hard decision on the received signal one by one in the order of the signal detection. By repeating the process of removing the interference component to the other received signals by the determined received signal, backward substitution means for sequentially detecting the T transmission signals, and the detected T transmission signals in the order list And a rearrangement means for rearranging and outputting in the original transmitted spatial order.

In the wireless reception device according to the present invention, the detection order determination unit generates the order list according to the matrix G and an order list generation formula, and the rearrangement unit rearranges the propagation path matrix H. Matrix H ′ obtained as a result of rearranging the matrix G and the matrix G ′ obtained by rearranging the matrix G, and the matrix R / matrix Q generator generates an upper triangular matrix from the matrix G ′ using a triangular matrix calculation formula. R is derived, and the matrix H ′ is orthogonalized using the upper triangular matrix R to generate and output a matrix Q. The filtering means multiplies the complex conjugate transpose of the matrix Q and the received signal vector x. The backward substitution means calculates a detected transmission signal vector by backward substitution calculation processing using the column vector y and the upper triangular matrix R, and T of the detected transmission signal vectors is calculated. Elements of Are sequentially detected, an interference component is calculated according to an interference component calculation formula, a soft decision detection signal is calculated by subtracting the interference component from the k th element y _{k of the} column vector y, and the soft decision detection signal On the other hand, a hard decision is made based on the constellation applied at the time of modulation on the transmission side, a hard decision detection signal is calculated, and the order rearranging means uses the detected transmission signal vector obtained by the backward substitution process as the After sorting according to the order list, the sorting result is output.

According to the present invention, in the above-described wireless reception device, the detection order determination unit decomposes the matrix G to derive an upper triangular matrix, and calculates an l-order norm in the p-th row of the inverse matrix U of the upper triangular matrix d and _l th power calculating the beta _p, it rearranges the values of the beta _p calculated for an inverse matrix U of the upper triangular matrix in ascending order, to generate the numerical values obtained in the rearrangement as ordered list, the rearrangement The means outputs a matrix H ′ resulting from rearranging the propagation path matrix H and a matrix G ′ resulting from rearranging the matrix G, and the matrix R / matrix Q generating means outputs the matrix G ′. The upper triangular matrix R is derived from the upper triangular matrix R using the upper triangular matrix R, the matrix H is orthogonalized using the upper triangular matrix R, and the matrix Q is generated and output. By multiplying the conjugate transpose and the received signal vector x The counter substitution means calculates a detection transmission signal vector by a backward substitution calculation process using the column vector y and the upper triangular matrix R, and calculates T elements of the detection transmission signal vector. Detecting in order, calculating an interference component according to an interference component calculation formula, subtracting the interference component from the k-th element y _{k of the} column vector y, calculating a soft decision detection signal, On the other hand, a hard decision is performed based on the constellation applied at the time of modulation on the transmission side to calculate a hard decision detection signal, and the order rearranging means converts the detected transmission signal vector obtained by the backward substitution process into the order. After sorting according to the list, the sorting result is output.

The present invention also relates to a radio reception apparatus that performs signal detection of a received signal using a propagation path matrix H, a predetermined coefficient α, and a received signal vector x in a MIMO (Multiple Input Multiple Output) system, and the transmission of the radio transmission apparatus For the T elements in the transmitted signal vector s of the transmitted signal, the order of signal detection is simultaneously determined by the received power calculated from the propagation path matrix H and the correlation between the propagation paths. The matrix G calculated from G = H ^H H + α ² I using the detection order determining means to be recorded in the list, the complex conjugate transpose of the channel matrix H, the channel matrix H, the coefficient α, and the unit matrix I Rearrangement means for rearranging row vectors and column vectors according to the order list S, a lower triangular matrix R is derived from the matrix obtained by rearranging the matrix G, and the column vector of the propagation path matrix H is rearranged. Matrix R / matrix Q generating means for generating a matrix Q by orthogonalizing the obtained matrix using the lower triangular matrix R, and filtering means for filtering a received vector x using a complex conjugate transpose of the matrix Q. Then, using the filtering result and the lower triangular structure of the lower triangular matrix R , a forward substitution process is performed on the filtered received vector to perform a hard decision on the received signal one by one in the order of the signal detection. Forward substitution means for sequentially detecting the T transmission signals by repeating the process of removing the interference component to the other reception signals by the determined reception signal, and the detected T transmission signals in the order list And a rearrangement means for rearranging and outputting in the original transmitted spatial order.

In the wireless reception device according to the present invention, the detection order determination unit generates the order list according to the matrix G and an order list generation formula, and the rearrangement unit rearranges the propagation path matrix H. The matrix H ′ obtained as a result of rearrangement and the matrix G ′ obtained as a result of rearranging the matrix G are output, and the matrix R / matrix Q generator generates a lower triangular matrix using a triangular matrix calculation formula from the matrix G ′. R is derived, and the matrix H ′ is orthogonalized using the lower triangular matrix R to generate and output a matrix Q. The filtering means multiplies the complex conjugate transpose of the matrix Q and the received signal vector x. The forward substitution means calculates a detected transmission signal vector by forward substitution calculation processing using the column vector y and the lower triangular matrix R, and T of the detected transmission signal vectors is calculated. Elements of Are sequentially detected, an interference component is calculated according to an interference component calculation formula, a soft decision detection signal is calculated by subtracting the interference component from the k th element y _{k of the} column vector y, and the soft decision detection signal On the other hand, a hard decision is performed based on the constellation applied at the time of modulation on the transmission side, a hard decision detection signal is calculated, and the order rearranging means calculates the detected transmission signal vector obtained by the forward substitution process as described above. After rearranging according to the order list, the rearrangement result is output.

According to the present invention, in the above-described wireless reception device, the detection order determination unit decomposes the matrix G to derive a lower triangular matrix, and calculates an l-order norm in the p-th row of the inverse matrix U of the lower triangular matrix d and _l th power calculating the beta _p, it rearranges the values of the beta _p calculated for an inverse matrix U of the lower triangular matrix in ascending order, to generate the numerical values obtained in the rearrangement as ordered list, the rearrangement The means outputs a matrix H ′ resulting from rearranging the propagation path matrix H and a matrix G ′ resulting from rearranging the matrix G, and the matrix R / matrix Q generating means outputs the matrix G ′. The lower triangular matrix R is derived from the lower triangular matrix R using the triangular matrix calculation formula, the matrix H ′ is orthogonalized using the lower triangular matrix R to generate and output the matrix Q, and the filtering means includes the complex of the matrix Q By multiplying the conjugate transpose and the received signal vector x The forward substitution means computes a detection transmission signal vector by forward substitution calculation processing using the column vector y and the lower triangular matrix R, and calculates T elements of the detection transmission signal vector. Detecting in order, calculating an interference component according to an interference component calculation formula, subtracting the interference component from the k-th element y _{k of the} column vector y, calculating a soft decision detection signal, On the other hand, a hard decision is performed based on the constellation applied at the time of modulation on the transmission side to calculate a hard decision detection signal, and the order rearranging means converts the detected transmission signal vector obtained by the forward substitution process into the order. After sorting according to the list, the sorting result is output.

Further, the present invention is a program executed by a computer of a radio reception apparatus that performs signal detection of a received signal using a propagation path matrix H, a predetermined coefficient α, and a received signal vector x in a MIMO (Multiple Input Multiple Output) system. The correlation between the received power calculated from the propagation path matrix H and the propagation path for the T elements in the transmission signal vector s of the signal transmitted by the wireless transmission apparatus. And a matrix calculated from G = H ^H H + α ² I using the processing of recording in the order list, the complex conjugate transposition of the channel matrix H, the channel matrix H, the coefficient α, and the unit matrix I A process of rearranging the row vector and the column vector of G according to the order list S, a triangular matrix R is derived from the matrix obtained by rearranging the matrix G, and the column vector of the propagation path matrix H is A process of generating a matrix Q by orthogonalizing the rearranged matrix using the triangular matrix, a process of filtering a received vector x using a complex conjugate transpose of the matrix Q, and using the triangular matrix R The received vector filtered and subjected to backward substitution processing or forward substitution processing to perform a hard decision on the received signal one by one in the order of the signal detection and interference components to other received signals due to the hard judged received signal A process of sequentially detecting the T transmission signals by repeating the removal process, and a process of outputting the detected T transmission signals by rearranging them in the original transmitted spatial order according to the order list. Is a program that causes a computer to execute.

Further, the present invention is a program executed by a computer of a radio reception apparatus that performs signal detection of a received signal using a propagation path matrix H, a predetermined coefficient α, and a received signal vector x in a MIMO (Multiple Input Multiple Output) system. The correlation between the received power calculated from the propagation path matrix H and the propagation path for the T elements in the transmission signal vector s of the signal transmitted by the wireless transmission apparatus. determined simultaneously by using a detection order determination process of recording the ordered list, the complex conjugate transpose and the channel matrix H of the channel matrix H and the coefficient alpha and matrix ^{I G = H H H + α} 2 I A rearrangement process for rearranging the row vector and the column vector of the matrix G calculated according to the order list S, and deriving an upper triangular matrix R from the rearranged matrix G, A matrix R / matrix Q generation process for generating a matrix Q by orthogonalizing a matrix in which column vectors of the propagation path matrix H are rearranged using the upper triangular matrix R, and complex conjugate transposition of the matrix Q are performed. A filtering process for filtering the received vector x using the filtering result and an upper triangular structure of the upper triangular matrix R, and performing a backward substitution process on the filtered received vector, so that one signal is detected in the order of the signal detection. The reverse substitution process for sequentially detecting the T transmission signals by repeating the process of performing a hard decision of the received signal and the process of removing the interference component to the other received signal by the hard-decided received signal, An order rearrangement process in which the detected T transmission signals are rearranged in the original transmitted spatial order according to the order list and output to the computer. To a program.

In the detection order determination process, the order list is generated in accordance with the matrix G and the order list generation formula. In the rearrangement process, the propagation path matrix H is rearranged. And the matrix G as a result of rearranging the matrix G, and in the matrix R / matrix Q generation process, an upper triangular matrix R is derived from the matrix G ′ using a triangular matrix calculation formula, The matrix H ′ is orthogonalized using the upper triangular matrix R to generate and output a matrix Q. In the filtering process, the complex conjugate transpose of the matrix Q and the received signal vector x are multiplied. A vector y is calculated, and in the backward substitution process, a detected transmission signal vector is calculated by a backward substitution calculation process using the column vector y and the upper triangular matrix R, and the detected transmission signal vector is calculated. Are sequentially detected, an interference component is calculated according to an interference component calculation formula, and a soft decision detection signal is calculated by subtracting the interference component from the k-th element y _{k of the} column vector y, The soft decision detection signal is subjected to a hard decision based on the constellation applied at the time of modulation on the transmission side to calculate a hard decision detection signal. In the order rearrangement process, the soft decision detection signal is obtained by the backward substitution process. This is a program for causing a computer to execute each process of rearranging the detected transmission signal vectors according to the order list and outputting the rearrangement result.

Further, according to the present invention, in the detection order determination process, the matrix G is decomposed to derive an upper triangular matrix, and the _l- th norm in the p-th row of the inverse matrix U of the upper triangular matrix is raised to the d ₁ power to β _p The β _p values calculated for the inverse matrix U of the upper triangular matrix are rearranged in ascending order, and the numerical values obtained by the rearrangement are generated as an ordered list. In the rearrangement process, the propagation A matrix H ′ as a result of rearranging the path matrix H and a matrix G ′ as a result of rearranging the matrix G are output. In the matrix R / matrix Q generation processing, a triangular matrix is calculated from the matrix G ′. An upper triangular matrix R is derived using an equation, and the matrix H ′ is orthogonalized using the upper triangular matrix R to generate and output a matrix Q. In the filtering process, a complex conjugate transpose of the matrix Q Multiplying the received signal vector x In the backward substitution process, the detected transmission signal vector is calculated by the backward substitution calculation process using the column vector y and the upper triangular matrix R, and T detected transmission signal vectors are calculated. The elements are detected in order, the interference component is calculated according to the interference component calculation formula, the soft decision detection signal is calculated by subtracting the interference component from the _kth element y _{k of the} column vector y, and the soft decision detection The signal is subjected to a hard decision based on the constellation applied at the time of modulation on the transmission side to calculate a hard decision detection signal. In the order rearrangement process, the detected transmission signal vector obtained by the backward substitution process Are rearranged according to the order list, and then each process of outputting the rearrangement result is executed by a computer.

Further, the present invention is a program executed by a computer of a radio reception apparatus that performs signal detection of a received signal using a propagation path matrix H, a predetermined coefficient α, and a received signal vector x in a MIMO (Multiple Input Multiple Output) system. The correlation between the received power calculated from the propagation path matrix H and the propagation path for the T elements in the transmission signal vector s of the signal transmitted by the wireless transmission apparatus. determined simultaneously by using a detection order determination process of recording the ordered list, the complex conjugate transpose and the channel matrix H of the channel matrix H and the coefficient alpha and matrix ^{I G = H H H + α} 2 I A rearrangement process for rearranging the row vector and the column vector of the matrix G calculated according to the order list S, and deriving a lower triangular matrix R from the rearranged matrix G, A matrix R / matrix Q generation process for generating a matrix Q by orthogonalizing a matrix in which column vectors of the propagation path matrix H are rearranged using the lower triangular matrix R, and complex conjugate transposition of the matrix Q are performed. Using the filtering process for filtering the received vector x using the filtering result and the lower triangular structure of the lower triangular matrix R, applying the forward substitution process to the filtered received vector, one in the order of the signal detection A forward substitution process for sequentially detecting the T transmission signals by repeating a process of performing a hard decision on the received signal and a process of removing an interference component to the other received signal by the hard-decided received signal, An order rearrangement process in which the detected T transmission signals are rearranged in the original transmitted spatial order according to the order list and output to the computer. To a program.

In the detection order determination process, the order list is generated in accordance with the matrix G and the order list generation formula. In the rearrangement process, the propagation path matrix H is rearranged. And the matrix G resulting from the rearrangement of the matrix G, and in the matrix R / matrix Q generation process, a lower triangular matrix R is derived from the matrix G ′ using a triangular matrix calculation formula, The matrix H ′ is orthogonalized using the lower triangular matrix R to generate and output a matrix Q. In the filtering process, the complex conjugate transpose of the matrix Q and the received signal vector x are multiplied. A vector y is calculated, and in the forward substitution process, a detected transmission signal vector is calculated by forward substitution calculation processing using the column vector y and the lower triangular matrix R, and the detected transmission signal vector Are sequentially detected, an interference component is calculated according to an interference component calculation formula, and a soft decision detection signal is calculated by subtracting the interference component from the k-th element y _{k of the} column vector y, The soft decision detection signal is subjected to a hard decision based on the constellation applied at the time of modulation on the transmission side to calculate a hard decision detection signal. In the order rearrangement process, the soft decision detection signal is obtained by the forward substitution process. This is a program for causing a computer to execute each process of rearranging the detected transmission signal vectors according to the order list and outputting the rearrangement result.

Further, according to the present invention, in the detection order determination process, the matrix G is decomposed to derive a lower triangular matrix, and the _l- th norm in the p-th row of the inverse matrix U of the lower triangular matrix is raised to the d ₁ power to β _p The β _p values calculated for the inverse matrix U of the lower triangular matrix are rearranged in ascending order, and the numerical values obtained by the rearrangement are generated as an ordered list. In the rearrangement process, the propagation A matrix H ′ as a result of rearranging the path matrix H and a matrix G ′ as a result of rearranging the matrix G are output. In the matrix R / matrix Q generation processing, a triangular matrix is calculated from the matrix G ′. A lower triangular matrix R is derived using an equation, and the matrix H ′ is orthogonalized using the lower triangular matrix R to generate and output a matrix Q. In the filtering process, a complex conjugate transpose of the matrix Q Multiplying the received signal vector x In the forward substitution process, a detected transmission signal vector is calculated by forward substitution calculation processing using the column vector y and the lower triangular matrix R, and T detected transmission signal vectors are calculated. The elements are detected in order, the interference component is calculated according to the interference component calculation formula, the soft decision detection signal is calculated by subtracting the interference component from the _kth element y _{k of the} column vector y, and the soft decision detection The signal is subjected to a hard decision based on the constellation applied at the time of modulation on the transmission side to calculate a hard decision detection signal, and in the order rearrangement process, the detected transmission signal vector obtained by the forward substitution process Are rearranged according to the order list, and then each process of outputting the rearrangement result is executed by a computer.

  The present invention is also a computer-readable recording medium on which any one of the above programs is recorded.

In the prior art, signal detection order determination and signal extraction vector generation for T transmission signals are performed by T pseudo inverse matrix operations, and transmission signals are detected in order using the extraction vectors. However, in the present invention, without first calculating the pseudo inverse matrix, first, the detection order is determined by a novel method, and then the system transfer coefficient matrix in which the column vectors are rearranged by triangulation is attempted. Further, the system transfer coefficient matrix is orthogonalized using the triangular matrix. Finally, using the triangular structure of the transfer coefficient matrix, T transmission signals are detected by backward substitution or forward substitution, and are rearranged in the original transmitted spatial order and output.
Thus, according to the above-described embodiment, it is not necessary to perform the pseudo inverse matrix calculation, and main calculation amounts are the detection order determination calculation, the QR decomposition calculation, and the backward or forward substitution calculation. Accordingly, the required calculation amount is extremely small as compared with the conventional SIC method. Therefore, it is possible to provide a signal detection device for a wireless reception device that has a smaller amount of processing operation and a smaller required operation circuit scale than conventional ones.

  Further, according to the present invention, since there is no calculation of the pseudo inverse matrix, the required storage capacity is small. Thereby, the required storage device capacity of the signal detection device of the wireless reception device can be reduced.

  Further, according to the present invention, since the required arithmetic circuit scale and the storage device are small, it is possible to easily reduce the size and weight of the signal detection device of the wireless reception device.

  According to the present invention, instead of T pseudo-inverse matrix operations, the detection order is determined by a novel method, and then the system transfer coefficient matrix in which the column vectors are rearranged by triangulation is triangulated. Further, the system transfer coefficient matrix is orthogonalized using the triangular matrix. Finally, T transmission signals are detected by backward substitution or forward substitution using the triangular structure of the transfer coefficient matrix. For this reason, the processing delay is greatly reduced. As a result, even when the number of transmission antennas is large, real-time processing is possible without increasing the clock frequency in the arithmetic circuit. That is, the processing delay of the signal detection device of the wireless reception device can be reduced.

  Further, according to the present invention, since the required power consumption is proportional to the required arithmetic circuit scale, the operation clock frequency, and the like, the signal detection device of the wireless reception device of the present invention has more power than the power consumption by the conventional MMSE-SIC method. Consumption is reduced. Therefore, it is possible to realize a long operating time of the MIMO system operated by the battery.

  In addition, according to the present invention, in the economical implementation of the signal detection device of the wireless reception device in hardware and software, the above-described effects can reduce the manufacturing cost and make it suitable for mass production.

Hereinafter, a wireless communication system according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a first diagram showing a configuration of a MIMO-OFDM system.
FIG. 2 is a second diagram showing the configuration of the MIMO-OFDM system.
FIG. 3 is a first diagram illustrating a configuration of the MIMO-Single system.
FIG. 4 is a second diagram showing the configuration of the MIMO-Single system.
In these MIMO systems, the system configuration shown in FIGS. 1 and 3 processes channel coding and symbol mapping in one series. Further, the system shown in FIGS. 2 and 4 is newly provided with a configuration for processing T signal sequences in parallel according to the number T of transmission antennas.

In a radio transmission apparatus (Transmitter) of a MIMO system, after T baseband modulation and passband processing are performed on T transmission signals s _t (t = 1, 2,... T), space is transmitted from T transmission antennas. Is sent to. In addition, in the MIMO system radio receiver (Receiver), T transmission signals multiplexed in space are received using R reception antennas, and after R band processing and baseband demodulation, R R signals are received. A received signal x _r (r = 1, 2,... R) is input to the signal detection device. The signal detection apparatus (Signal Detector) has a function of detecting a signal spatially multiplexed, and outputs the T number of detection signals ^ s _t detected by this processing. Here, the signal detection may be referred to as signal separation or interference canceller, but the essence is to detect a signal for each transmission system transmitted by the wireless transmission device from a spatially multiplexed signal.

In MIMO-OFDM system and MIMO-Single system can be expressed with its T transmit signal _{s t,} the relationship between the R received signals _{x r} in equation (1).

In this equation (1), “s” represents a transmission signal vector of T × 1 (T rows and 1 column). “X” represents a received signal vector of R × 1 (R rows and 1 column). “W” represents an R × 1 noise component vector. “H” represents a system transfer coefficient matrix of R × T (R rows and T columns). All subscript numbers represent spatial indexes. For example, s ₄ is a transmission signal transmitted by the fourth transmission antenna in the wireless transmission device, x ₂ is a reception signal received by the second reception antenna in the wireless reception device, and w ₁ is the _first reception in the wireless reception device. Noise components added by the antenna, h _{3 and 2} , represent transmission coefficients in the radio link connecting the second transmission antenna in the radio transmission apparatus and the third reception antenna in the radio reception apparatus. Furthermore, in the MIMO-OFDM system, the above equation (1) can be expressed as the following equation (2).

In this equation (2), n represents a time index. K represents a frequency index. Further, Expression (2) limits Expression (1) to a mathematical relationship between T transmission signals and R reception signals in the kth subcarrier of the nth OFDM signal at the time. Further, in the MIMO-Single system, Expression (1) can be expressed as Expression (3).

In this formula (3), n represents a time index. Further, Expression (3) limits Expression (1) to a mathematical relationship between T transmission signals and R reception signals in the n-th single carrier modulation signal. However, since the signal detection method of the present invention can be implemented in the same manner for all time indexes and frequency indexes in the MIMO system, n and k are omitted in the following description. If it is necessary to re-estimate the value of the propagation path matrix H as time and frequency change, the estimation process is performed. Further, it is assumed that the frequency and time are normally synchronized between the transmitting and receiving apparatuses in the MIMO system. Hereinafter, a signal detection method of the radio reception apparatus in the MIMO system shown in FIGS. 1 to 4 will be described.

<Example 1>
Assume that the input to the signal detection device in the wireless reception device is the propagation path matrix H, the coefficient α, and the reception signal vector x, and the signal output through the signal detection processing according to the present embodiment is the detection signal ^ s (symbol ^ Indicates a hat), the signal detection device
(Step S1a) With respect to T elements s = [s ₁ , s ₂ ,..., S _T ] in the transmission signal vector s, the order of signal detection is simultaneously determined and the list S is obtained. Record.
(Step S1b) The matrix H ′ and the matrix G ′ are calculated by rearranging the column vector of the propagation path matrix H and the row and column vectors of the matrix G according to the order list S determined in Step S1a.
(Step S1c) The matrix G ′ in which the row and column vectors are rearranged is decomposed into an upper triangular matrix R. Also, using the upper triangular matrix R, the matrix H ′ in which the column vectors are rearranged is orthogonalized to generate a matrix Q.
(Step S1d) The received vector x is filtered using the matrix Q complex conjugate transpose.
(Step S1e) Using the upper triangular structure of R, T transmission signals are sequentially detected by backward substitution.
(Step S1f) According to the list S, the detected T transmission signals are rearranged in the original transmitted spatial order (antenna order) and output.
Here, in the signal detection apparatus, only the process of step S1e includes iterative calculation, but the processes of other steps S1a to 1d and 1f need only be executed once.

The matrix decomposition in step S1c described above is a process performed to decompose a Hermitian matrix A (that is, A ^H = A) of a certain T row and T column and derive an upper triangular matrix R of T row and T column, It can be expressed by equation (4).

Next, the details of the above-described processes (step S1a) to (step S1f) will be described.
<About Step S1a>
For the T elements s = [s ₁ , s ₂ ,..., S _T ] in the transmission signal vector s, the respective signal detection orders are simultaneously determined and recorded in the list S. Then, the matrix G is calculated by Expression (5) using the propagation path matrix H defined as Expression (1).

Here, the coefficient α = σ _w / σ _s , where σ _w and σ _s represent the variance of the noise component and the variance of the transmission signal, respectively. If the values of σ _w and σ _s are not known, it is possible to estimate them and obtain the coefficient α using the estimated values. Also, the coefficient α can be set to other values according to the requirements of the MIMO system. For example, the coefficient α = 0 is set. When the coefficient α = 0, G = H ^H H.

Next, using the elements of the matrix G, V _p is calculated by Equation (6). However, v (i, j) is defined as in equation (7).

In Expression (7), d _{1 to} d ₅ are values determined according to the system requirements of the MIMO system according to the present embodiment. Next, β _p is calculated using V _{p according} to equation (8).

Here, since the propagation path matrix H has T column vectors, T values of β _p are calculated from β ₁ to β _T accordingly. Then, the calculated T β _p are rearranged in descending order by comparing the magnitudes as shown in Equation (9).

When T = 3 in Equation (9), it is assumed that β ₁ = 0.3, β ₂ = 5.7, and β ₃ = 1.8 for a certain channel matrix H. Then, according to the equation (9), β ₂ ≧ β ₃ ≧ β ₁ → β _p1 ≧ β _p2 ≧ β _p3 , p ₁ = 2, p ₂ = 3, p ₃ = 1.

Next, the numerical values from p ₁ to p _T obtained by the magnitude comparison and rearrangement in Expression (9) are recorded as a detection order list S of T transmission signals as in Expression (10). Expressions (6) to (10) are taken as an order list generation expression.

As described above, assuming T = 3, β ₁ = 0.3, β ₂ = 5.7, and β ₃ = 1.8 for a certain channel matrix H, S = {p ₃ , p ₂ , p ₁ } = { _{1, 3, 2} }. That is, the transmission signal s ₂ is detected _first , s ₃ is detected second, and s ₁ is detected third. Note that p _k (k = 1,..., T) means that the transmission signal s _pk is detected k-th.

<About Step S1b>
Next, the column vector of the propagation path matrix H and the row and column vectors of the matrix G are rearranged according to the order list S determined in step S1a. Expressions (11) and (12) are mathematical expressions used for the rearrangement.

In Expressions (11) and (12), P corresponds to a rearrangement matrix, and its column vector is composed of e _pT ,..., E _p2 , e _p1 . Here, e _k is a column vector of T rows and 1 column, the k th element is 1 and the others are 0. A propagation path matrix after rearrangement as shown in Expression (11) or after processing equivalent to the rearrangement is represented as H ′. For example in the case of _{S = {p 3, p 2} , p 1} = {1,3,2} is _{P = [e p3, e p2} , e p1] = [e 1, e 3, e 2]. Therefore, the column vector of H is rearranged by P as shown in Expression (13).

In this case, the multiplication of the matrices H and P does not actually require a mathematical operation, and the matrix P may be rearranged according to the order list S and the column vectors of H are rearranged. That is, even when step S1b is actually implemented, the H column vectors may be rearranged according to the list S. For matrix G, both rows and columns are reordered according to equation (12).

<Regarding Step S1c>
Next, in step S1b, the matrix G ′ in which rows and columns are rearranged for the matrix G is decomposed to derive an upper triangular matrix R. Also, using the upper triangular matrix R, the matrix H ′ in which the column vectors are rearranged is orthogonalized to generate a matrix Q. The process of decomposing the matrix G ′ to derive the upper triangular matrix R is expressed by Expression (14).

There are several methods for deriving the upper triangular matrix R as shown in Equation (14). For example, Gaxpy Cholesky decomposition method or Outer Product Cholesky decomposition method. What kind of decomposition method to use is determined based on implementation considerations. Further, the generation of the matrix Q is orthogonalized by Expression (15), where q _t (t = 1, 2,... T) is the order from the left in the column vector.

That is, using the equation (15), the column vector of the matrix H ′ is orthogonalized in order from left to right, and the obtained result is defined as a matrix Q.

<About Step S1d>
Next, the column vector y is calculated using the complex conjugate transpose of the matrix Q calculated in step S1c, and the received vector x is filtered as shown in Expression 16.

Here, s ′ represents a matrix in which the order of the elements of the transmission signal vector s is rearranged by the matrix ^PT . V represents the synthesis of the noise component vector and the interference component vector after the linear filtering process. The column vector y includes a column vector v obtained by multiplying the matrix R and the column vector s ′ and synthesizing the noise component and the interference component.

<About Step S1e>
Next, using the upper triangular structure of R, T transmission signals are sequentially detected by backward substitution. The calculated column vector y can be written for each element as shown in equation (17).

In Equation (17), r _{k, k} , r _{k, i} , v _k (k = T,..., 1) represent elements in the matrix R and the vector v, respectively. In the backward substitution process, the following three expressions (18), (19), and (20) are calculated from k = T to k = 1 (that is, k = T, T−1,..., 1). Repeat. Expression (18) is an operation (interference component calculation expression) for calculating an interference component for the transmission signal s _k ^′ . In this calculation, when K = T, the interference component is 0, that is, ^ m _T = 0. The subtracting the interference component ^ m _k from the k-th element y _k of the column vector Equation (19), the soft decision result ^~ s _k 'of the transmission signal ^(~ symbol indicates the tilde) is a calculation for obtaining a. The equation (20) is a process of performing a hard decision based on the cons sauce Deployment applied during modulation at the transmission side with respect to formula (19) soft decision result ^{~ s} k obtained in _'.

Then, the processing according to the above equations (18) to (20) is executed T times from k = T to k = 1, and the transmission signal vector ^ s' = [^ s ₁ ', ^ s ₂ ', ..., ^ s _T '] ^T is obtained.

<Regarding Step S1f>
Next, the T transmission signals detected are rearranged in the original transmitted spatial order (antenna order) according to the order list S and output. Using the transpose of the matrix P as shown in Expression (21), the rearrangement processing of the order of the transmission signal ^ s ′ detected in Step S1e is performed. The matrix P is the same as the matrix P obtained according to the detection order list S in the process of step S1b.

For example, similarly to step S1b, in the case of S = {p ₃ , p ₂ , p ₁ } = { ₁ , ₃ , ₂ }, P = [e ₁ , e ₃ , e ₂ ] = [e ₁ , e ₃ , E ₂ ] ^T. Therefore, each element of ^ s ^' is rearranged by P as shown in Expression (22).

  Here, the multiplication of the matrix P and ^ s' shown in the equation (22) does not actually require a mathematical operation, and the signal detection apparatus inside the wireless reception apparatus has the matrix P according to the order list S. It only needs to have a function to sort the elements of '. After the rearrangement processing is completed, the detected transmission signal vector ^ s is output from the signal detection device, and the next processing unit of the wireless reception device performs the processing.

Next, the configuration of the signal detection device will be described.
FIG. 5 is a first diagram illustrating a function processing unit of the signal detection device.
FIG. 6 is a second diagram illustrating the function processing unit of the signal detection device.
FIG. 7 is a third diagram illustrating the function processing unit of the signal detection device.
First, in FIG. 5, function processing units denoted by reference numerals 11 to 16 correspond to function processing units that perform processes corresponding to the above-described steps S1a to S1f, respectively. Here, the function processing unit means a circuit group in the signal detection device or a program group executed by the device. Reference numeral 17 represents a readable / writable storage device or an information pipeline (wiring).

  Reference numeral 11 denotes a detection order determination processing unit (Ordering). The detection order determination processing unit 11 reads or receives the propagation path matrix H and the coefficient α from the storage device (or pipeline) 17, calculates the order list S and the matrix G by arithmetic processing, and writes them to the storage device 17. (Or output to the pipeline). As shown in FIG. 6, the configuration of the detection order determination processing unit 11 is further divided into 11a and 11b. Reference numeral 11a denotes a matrix G calculation processing unit (G Computation). 11a reads or receives the propagation path matrix H and the coefficient α from the storage device (or pipeline) 17, calculates the matrix G according to the equation (5), and records it in the storage device 17 (or outputs it to the pipeline). To do). Reference numeral 11b denotes an order list determination processing unit (S Determination). The order list determination processing unit 11b reads or receives the matrix G from the storage device (or pipeline) 17, generates a signal detection order list S according to the equations (6) to (10), and stores it in the storage device 17. Write (or output to pipeline).

  Reference numeral 12 denotes a channel matrix vector rearrangement processing unit (Column Exchange). The propagation path matrix vector rearrangement processing unit 12 reads or receives the signal detection order list S, the propagation path matrix H, and the matrix G from the storage device (or pipeline) 17 and receives the propagation path matrix H and the propagation path matrix H according to the signal detection order list S. After rearranging the matrix G, the results H ′ and G ′ are written into the storage device 17 (or output to the pipeline).

  Reference numeral 13 denotes a matrix R / matrix Q generator (R, Q Generation). The matrix R / matrix Q generator 13 reads or receives the matrix H ′ matrix G from the storage device (or pipeline) 17, derives the matrix R by the processing according to the equation (4), and further derives the matrix R by the equation (15). The matrix Q is calculated by orthogonalizing H ′. They are written to the storage device 17 (or output to the pipeline).

Reference numeral 14 denotes a filtering processing unit (Q ^H Filtering). The filtering processing unit 14 reads or receives the matrix Q and the received signal vector x from the storage device (or pipeline) 17, calculates the vector y by multiplying the complex conjugate transpose of Q and x, and stores it in the storage device. Write to 17 (or output to pipeline).

Reference numeral 15 denotes a backward substitution processing unit (Back Substitution). The backward substitution processing unit 15 reads or receives the column vector y and the matrix R from the storage device (or pipeline) 17, calculates the detected transmission signal vector ^ s' by the backward substitution calculation process, and detects the detected transmission signal vector ^ Write s ^′ to the storage device 17 (or output to the pipeline). As shown in FIG. 7, the backward substitution processing unit 15 further includes functional processing units of an interference component calculation processing unit (Interference Computation) 15a, a subtraction processing unit (subtractor) 15b, and a quantization processing unit (Quantiztion) 15c. Yes. Until From k = T a k = 1, is detected in the order of 'the elements of ^ s _T' detect signal vector ^ s each functional processing unit with T times in FIG. 7 to ^ s 1 _'. Then, the interference component calculation processing unit 15a reads or receives r _{k, i} and ^ s _i ′ (i = k + 1, k + 2,..., T) from the storage device (or pipeline) 17, and performs interference according to the equation (18). The component ^ _mk is calculated and sent to the subtraction processing unit 15b. The subtraction processing unit 15b or receive reading k-th element y _k column vectors y from a storage device (or pipeline) 17, soft decision detection signal by subtracting the interference component ^ m _k from the element y _k calculating a ^~ s _k ', and sends it to the quantization processing unit 15c. Then, the quantization processing unit 15c makes a hard decision based on the constellation applied at the time of modulation ^to the soft decision detection signal ˜s _k ′ that has received the input, and the hard decision detection signal ｓ _k ′. Is written into the storage device 17 (or output to the pipeline).

  Reference numeral 16 denotes an order rearrangement processing unit (Row Exchange). The order rearrangement processing unit 16 reads ^ s 'and the order list S from the storage device (or pipeline) 17, sorts ^ s' in accordance with the order list S, and then sends the transmission signal vector ^ s as a result. Output from the detection device.

<Example 2>
Next, Example 2 will be described.
As in the first embodiment, it is assumed that the input to the signal detection device in the wireless reception device is the propagation path matrix H, the coefficient α, and the reception signal vector x, and the signal output through the signal detection processing according to the present embodiment is the detection signal. When ^ s, the signal detection device is
(Step S2a) For the T elements s = [s ₁ , s ₂ ,..., S _T ] in the transmission signal vector s, the order of signal detection is simultaneously determined, and the order list S To record.
(Step S2b) Next, the signal detection apparatus rearranges the row and column vectors of the propagation path matrices H and G according to the order list S, and calculates the matrix H ′ and the matrix G ′.
(Step S2c) The lower triangular matrix R is derived from the matrix G ′ in which the row vector and the column vector are rearranged, and the lower triangular matrix R is used to orthogonalize the matrix H ′ in which the column vector is rearranged. Is generated.
(Step S2d) The received vector x is filtered using the complex conjugate transpose of the matrix Q.
(Step S2e) Using the lower triangular structure of the lower triangular matrix R, T transmission signals are sequentially detected by forward substitution.
(Step S2f) The detected T transmission signals are rearranged in the original transmitted spatial order (antenna order) according to the list S and output.
Here, the signal detection apparatus repeatedly calculates only the process 2e, but the other processes 2a to 2d and 2f need only be executed once.

The matrix decomposition in step S2c described above is a process performed to decompose a Hermitian matrix A of T rows and T columns (that is, A ^H = A) to derive an upper triangular matrix R of T rows and T columns, It can be represented by formula (23).

Next, details of the above-described processes of (Step S2a) to (Step S2f) will be described.
<About Step S2a>
For the T elements s = [s ₁ , s ₂ ,..., S _T ] in the transmission signal vector s, the respective signal detection orders are simultaneously determined and recorded in the list S. Then, the matrix G is calculated by Expression (24) using the propagation path matrix H defined as Expression (1).

Here, the coefficient α = σ _w / σ _s , where σ _w and σ _s represent the variance of the noise component and the variance of the transmission signal, respectively. If the values of σ _w and σ _s are not known, it is possible to estimate them and obtain the coefficient α using the estimated values. Also, the coefficient α can be set to other values according to the requirements of the MIMO system. For example, the coefficient α = 0 is set. When the coefficient α = 0, G = H ^H H.

Next, using the elements of the matrix G, V _p is calculated by Equation (25). However, v (i, j) is defined as in equation (26).

In Expression (26), d _{1 to} d ₅ are values determined according to the system requirements of the MIMO system according to the present embodiment. Next, β _p is calculated using V _{p according} to equation (27).

Here, since the propagation path matrix H has T column vectors, T values of β _p are calculated from β ₁ to β _T accordingly. Then, the calculated T β _p are rearranged in descending order by comparing the magnitudes as shown in Equation (28).

When T = 3 in equation (28), it is assumed that β ₁ = 0.3, β ₂ = 5.7, and β ₃ = 1.8 for a certain channel matrix H. Then, according to the equation (28), β ₂ ≧ β ₃ ≧ β ₁ → β _p1 ≧ β _p2 ≧ β _p3 , p ₁ = 2, p ₂ = 3, and p ₃ = 1.

Next, the numerical values from p ₁ to p _T obtained by the magnitude comparison and rearrangement in Expression (28) are recorded as a detection order list S of T transmission signals as in Expression (29). Expressions (25) to (29) are taken as an order list generation expression.

As described above, assuming T = 3, β ₁ = 0.3, β ₂ = 5.7, and β ₃ = 1.8 for a certain channel matrix H, S = {p ₁ , p ₂ , p ₃ } = {2, _{3, 1} }. That is, the transmission signal s ₂ is detected _first , s ₃ is detected second, and s ₁ is detected third. Note that p _k (k = 1,..., T) means that the transmission signal s _pk is detected k-th.

<About Step S2b>
Next, the column vector of the propagation path matrix H and the row vector and column vector of the matrix G are rearranged according to the order list S determined in step S2a. Expressions (30) and (31) are mathematical expressions used for the rearrangement.

In Expressions (30) and (31), P corresponds to a rearrangement matrix, and its column vector is composed of e _p1 , e _p2 ,..., E _pT . Here, e _k is a column vector of T rows and 1 column, the k th element is 1 and the others are 0. A propagation path matrix after rearrangement as shown in Expression (30) or after processing equivalent to the rearrangement is represented as H ′. For example in the case of _{S = {p 1, p 2} , p 3} = {2,3,1} is _{P = [e p1, e p2} , e p3] = [e 2, e 3, e 1]. Therefore, the column vector of H is rearranged by P as shown in Expression (32).

In this case, the multiplication of the matrices H and P does not actually require a mathematical operation, and the matrix P may be rearranged according to the order list S and the column vectors of H are rearranged. That is, even when step S2b is actually implemented, the H column vectors may be rearranged according to the list S. For matrix G, both rows and columns are rearranged according to equation (31).

<About Step S2c>
Next, in step S2b, the matrix G ′ in which the row vector and the column vector are rearranged for the matrix G is decomposed to derive a lower triangular matrix R. Also, using the lower triangular matrix R, the matrix H ′ in which the column vectors are rearranged is orthogonalized to generate a matrix Q. Processing for decomposing the matrix G ′ to derive the lower triangular matrix R is expressed by Expression (33).

There are several possible methods for deriving the lower triangular matrix R as shown in Equation (33). For example, Gaxpy Cholesky decomposition method or Outer Product Cholesky decomposition method. What kind of decomposition method to use is determined based on implementation considerations. In addition, in the process of generating the matrix Q, the order from the left in the column vector is q _t (t = 1, 2,... T), and is orthogonalized by Expression (34).

That is, using the equation (34), the column vector of the matrix H ′ is orthogonalized in order from left to right, and the obtained result is defined as a matrix Q.

<About Step S2d>
Next, a column vector y is calculated using the complex conjugate transpose of the matrix Q calculated in step S2c, and the received vector x is filtered as shown in Expression 35.

Here, s ′ represents a matrix in which the order of the elements of the transmission signal vector s is rearranged by the matrix ^PT . V represents the synthesis of the noise component vector and the interference component vector after the linear filtering process. The column vector y includes a column vector v obtained by multiplying the matrix R and the column vector s ′ and synthesizing the noise component and the interference component.

<About Step S2e>
Next, using the lower triangular structure of R, T transmission signals are sequentially detected by forward substitution. The calculated column vector y can be written for each element as shown in Expression (36).

In Equation (36), r _{k, k} , r _{k, i} , v _k (k = T,..., 1) represent elements in the matrix R and the vector v, respectively. In the forward substitution process, the following three expressions (37), (38), and (39) are calculated from k = 1 to k = T (that is, k = 1, 2,..., T−1, T) Repeat. Expression (37) is an operation (interference component calculation expression) for calculating an interference component for the transmission signal s _k ^′ . In this calculation, when K = 1, the interference component is 0, that is, ^ m ₁ = 0. The subtracting interference components ^ m _k from the k-th element y _k of the column vector Equation (38), the soft decision result ^~ s _k 'of the transmission signal ^(~ symbol indicates the tilde) is a calculation for obtaining a. The equation (39) is a process of performing a hard decision based on the cons sauce Deployment applied during modulation at the transmission side with respect to formula (38) soft decision result ^{~ s} k obtained in _'.

Then, the processing by the above equations (37) to (39) is executed T times from k = 1 to k = T, and the transmission signal vector ^ s' = [^ s ₁ ', ^ s ₂ ', ..., ^ s _T '] ^T is obtained.

<About Step S2f>
Next, the T transmission signals detected are rearranged in the original transmitted spatial order (antenna order) according to the order list S and output. Using the transpose of the matrix P as shown in Expression (40), the rearrangement process of the order of the transmission signal ^ s ′ detected in Step S1e is performed. The matrix P is the same as the matrix P obtained according to the detection order list S in the process of step S2b.

For example, similarly to step S2b, in the case of S = {p ₁ , p ₂ , p ₃ } = { ₂ , ₃ , ₁ }, P = [e ₂ , e ₃ , e ₁ ] = [e ₃ , e ₁ , E ₂ ] ^T. Therefore, each element of ^ s ^' is rearranged by P as shown in Expression (41).

  Here, the multiplication of the matrix P and ^ s' shown in the equation (41) does not actually require a mathematical operation, and the signal detection apparatus inside the wireless reception apparatus has the matrix P according to the order list S. It only needs to have a function to sort the elements of '. After the rearrangement processing is completed, the detected transmission signal vector ^ s is output from the signal detection device, and the next processing unit of the wireless reception device performs the processing.

  In addition, about the structure of the signal detection apparatus of Example 2, it becomes the structure by which the backward substitution process part 15 was replaced with the forward substitution process part (Forword Substitution). And the process performed in each function process part is performed according to said step S2a-step S2f.

Next, the configuration of the signal detection device will be described.
FIG. 8 is a fourth diagram illustrating the function processing unit of the signal detection device.
FIG. 9 is a fifth diagram illustrating the function processing unit of the signal detection device.
FIG. 10 is a sixth diagram illustrating the function processing unit of the signal detection device.
First, in FIG. 5, function processing units denoted by reference numerals 21 to 26 correspond to function processing units that perform processes corresponding to the above-described steps S2a to S2f, respectively. Here, the function processing unit means a circuit group in the signal detection device or a program group executed by the device. Reference numeral 27 denotes a readable / writable storage device or an information pipeline (wiring).

  Reference numeral 21 denotes a detection order determination processing unit (Ordering). The detection order determination processing unit 21 reads or receives the propagation path matrix H and the coefficient α from the storage device (or pipeline) 27, calculates the order list S and the matrix G by arithmetic processing, and writes them to the storage device 27. (Or output to the pipeline). As shown in FIG. 9, the configuration of the detection order determination processing unit 21 is further divided into 21a and 21b. Reference numeral 21a denotes a matrix G calculation processing unit (G Computation). 21a reads or receives the propagation path matrix H and the coefficient α from the storage device (or pipeline) 27, calculates the matrix G according to the equation (24), and records it in the storage device 27 (or outputs it to the pipeline). To do). Reference numeral 21b denotes an order list determination processing unit (S Determination). The order list determination processing unit 21b reads or receives the matrix G from the storage device (or pipeline) 27, generates a signal detection order list S according to the equations (25) to (29), and stores it in the storage device 27. Write (or output to pipeline).

  Reference numeral 22 denotes a channel matrix vector rearrangement processing unit (Column Exchange). The propagation path matrix vector rearrangement processing unit 22 reads or receives the signal detection order list S, the propagation path matrix H, and the matrix G from the storage device (or pipeline) 27, and the propagation path matrix H and the propagation path matrix H according to the signal detection order list S. After rearranging the matrix G, the results H ′ and G ′ are written into the storage device 27 (or output to the pipeline).

  Reference numeral 23 denotes a matrix R / matrix Q generator (R, Q Generation). The matrix R / matrix Q generation unit 23 reads or receives the matrix H ′ matrix G from the storage device (or pipeline) 27, derives the matrix R by processing according to the equation (23), and further calculates the matrix R by the equation (34). The matrix Q is calculated by orthogonalizing H ′. They are written into the storage device 27 (or output to the pipeline).

Reference numeral 24 denotes a filtering processing unit (Q ^H Filtering). The filtering processing unit 24 reads or receives the matrix Q and the received signal vector x from the storage device (or pipeline) 27, calculates the vector y by multiplying the complex conjugate transpose of Q and x, and stores it in the storage device. Write to 27 (or output to pipeline).

Reference numeral 25 denotes a forward substitution processing unit (Back Substitution). The forward substitution processing unit 25 reads or receives the column vector y and the matrix R from the storage device (or pipeline) 27, calculates the detected transmission signal vector ^ s' by the forward substitution calculation process, and detects the detected transmission signal vector ^ s ^′ is written to the storage device 27 (or output to the pipeline). As shown in FIG. 10, the forward substitution processing unit 25 further includes functional processing units of an interference component calculation processing unit (Interference Computation) 25a, a subtraction processing unit (subtractor) 25b, and a quantization processing unit (Quantiztion) 25c. Yes. Until From k = T a k = 1, is detected in the order of 'the elements of ^ s _T' detect signal vector ^ s each functional processing unit with T times in FIG. 10 to ^ s 1 _'. Then, the interference component calculation processing unit 25a reads or receives r _{k, i} and ^ s _i ′ (i = k + 1, k + 2,..., T) from the storage device (or pipeline) 27, and performs interference according to the equation (37). The component ^ _mk is calculated and sent to the subtraction processing unit 25b. The subtraction processing unit 25b or receive reading k-th element y _k column vectors y from a storage device (or pipeline) 27, soft decision detection signal by subtracting the interference component ^ m _k from the element y _k calculating a ^~ s _k ', and sends it to the quantization processing unit 25c. Then, the quantization processing unit 25c performs a hard decision based on the constellation applied at the time of modulation on the transmission side with respect ^to the soft decision detection signal ˜s _k ′ that has received the input, and the hard decision detection signal ^ s _k ′. Is written into the storage device 27 (or output to the pipeline).

  Reference numeral 26 denotes an order rearrangement processing unit (Row Exchange). The order rearrangement processing unit 26 reads ^ s 'and the order list S from the storage device (or pipeline) 27, rearranges ^ s' according to the order list S, and then transmits the transmission signal vector ^ s as a result. Output from the detection device.

In the prior art, signal detection order determination and signal extraction vector generation for T transmission signals are performed by T pseudo inverse matrix operations, and transmission signals are detected in order using the extraction vectors. However, in the first and second embodiments of the present invention, without first calculating the pseudo inverse matrix, the detection order is first determined by a novel method, and then the column vectors are rearranged by triangulation. The system transfer coefficient matrix is triangulated, and the system transfer coefficient matrix is orthogonalized using the triangular matrix. Finally, using the triangular structure of the transfer coefficient matrix, T transmission signals are detected by backward substitution or forward substitution, and are rearranged in the original transmitted spatial order and output.
Thus, according to the first and second embodiments described above, it is not necessary to perform a pseudo inverse matrix operation, and main calculation amounts are a detection order determination operation, a QR decomposition operation, and a backward or forward substitution operation. . Accordingly, the required calculation amount is extremely small as compared with the conventional SIC method. Therefore, it is possible to provide a signal detection device for a wireless reception device that has a smaller amount of processing operation and a smaller required operation circuit scale than conventional ones.

  In addition, according to the first and second embodiments of the present invention, the required storage capacity is small because there is no calculation of the pseudo inverse matrix. Thereby, the required storage device capacity of the signal detection device of the wireless reception device can be reduced.

  Further, according to the first and second embodiments of the present invention, since the required arithmetic circuit scale and the storage device are small, it is possible to easily reduce the size and weight of the signal detection device of the wireless reception device.

  Also, according to the first and second embodiments of the present invention, instead of T pseudo inverse matrix operations, the detection order is determined by a novel method, and then column vectors are rearranged by triangulation. The system transfer coefficient matrix is triangulated, and the system transfer coefficient matrix is orthogonalized using the triangular matrix. Finally, T transmission signals are detected by backward substitution or forward substitution using the triangular structure of the transfer coefficient matrix. For this reason, the processing delay is greatly reduced. As a result, even when the number of transmission antennas is large, real-time processing is possible without increasing the clock frequency in the arithmetic circuit. That is, the processing delay of the signal detection device of the wireless reception device can be reduced.

  Further, according to the first and second embodiments of the present invention, the required power consumption is proportional to the required arithmetic circuit scale, the operation clock frequency, etc., and therefore the power consumption of the present invention is higher than that of the conventional MMSE-SIC method. In the signal detection device of the wireless reception device, power consumption is reduced. Therefore, it is possible to realize a long operating time of the MIMO system operated by the battery.

  Further, according to the first and second embodiments of the present invention, in the economical implementation of the signal detection device of the radio reception device in hardware and software, the above-described effects make the manufacturing cost low and suitable for mass production. It will be.

  The most important features in the first and second embodiments of the present invention are: 1. A new signal detection order determination method has been devised. 2. Invented a method for triangulation and orthogonalization based on the system transfer coefficient matrix. 3. Invented a method of signal detection by backward or forward substitution using the triangular structure of the system transfer coefficient matrix. 4. Proposed a method of rearranging the elements of the transmission signal detected by the backward transfer or forward substitution and the order determined in (1.) above, with the column vector and matrix G of the system transfer coefficient matrix. It is that a method of combining (1.), (2.), (3.) and (4.) is devised.

<Example 3>
Next, Example 3 will be described. The third embodiment is a modification of the first embodiment.
As in the first embodiment, it is assumed that the input to the signal detection device in the wireless reception device is the propagation path matrix H, the coefficient α, and the reception signal vector x, and the signal output through the signal detection processing according to the present embodiment is the detection signal. When ^ s, the signal detection device is
(Step S3a) With respect to T elements s = [s ₁ , s ₂ ,..., S _T ] in the transmission signal vector s, the order of signal detection is simultaneously determined and the list S is obtained. Record.
(Step S3b) The matrix H ′ and the matrix G ′ are calculated by rearranging the column vector of the propagation path matrix H and the row and column vectors of the matrix G according to the order list S determined in Step S3a.
(Step S3c) The matrix G ′ in which the row and column vectors are rearranged is decomposed into an upper triangular matrix R. Also, using the upper triangular matrix R, the matrix H ′ in which the column vectors are rearranged is orthogonalized to generate a matrix Q.
(Step S3d) The received vector x is filtered using the matrix Q complex conjugate transpose.
(Step S3e) Using the upper triangular structure of R, T transmission signals are sequentially detected by backward substitution.
(Step S3f) According to the list S, the detected T transmission signals are rearranged in the original transmitted spatial order (antenna order) and output.
Here, in the signal detection apparatus, only the process of step S3e includes iterative calculation, but the other processes of steps S3a to 3d and 3f need only be executed once.

The matrix decomposition in step S3c described above is a process performed to decompose a Hermitian matrix A (that is, A ^H = A) of a certain T row and T column and derive an upper triangular matrix R of T row and T column, It can be represented by formula (42).

Note that the outline of the processing of (Step S3a) to (Step S3f) described above is the same as that of (Step S1a) to (Step S1f), but differs from the first embodiment mainly in the details of the processing of Step S3a.
Next, the details of the above-described processes (step S3a) to (step S3f) will be described.
<Regarding Step S3a>
For the T elements s = [s ₁ , s ₂ ,..., S _T ] in the transmission signal vector s, the respective signal detection orders are simultaneously determined and recorded in the list S. Then, the matrix G is calculated by the equation (43) using the propagation path matrix H defined as the equation (1).

Here, the coefficient α = σ _w / σ _s , where σ _w and σ _s represent the variance of the noise component and the variance of the transmission signal, respectively. If the values of σ _w and σ _s are not known, they can be estimated and the coefficient α can be obtained using the estimated values. Also, the coefficient α can be set to other values according to the requirements of the MIMO system. For example, the coefficient α = 0 is set. When the coefficient α = 0, G = H ^H H.

  Next, the matrix G calculated by Expression (43) is decomposed as shown in Expression (4), and is represented using the upper triangular matrix R. Expression (44) is an expression obtained by decomposing the matrix G and using the upper triangular matrix R.

  There are several methods for decomposing the matrix G using the upper triangular matrix R as shown in the equation (44), for example, Gaxpy Cholesky decomposition method, Outer Product Cholesky decomposition method and the like. The specific decomposition method to be used should be determined based on implementation considerations.

  Next, the signal detection device calculates an inverse matrix U of the upper triangular matrix R using Expression (45).

Then, the signal detection device calculates β _p by multiplying the _l- th norm in the p-th row of the matrix U to the d ₁ power using Expression (46). Here, l and d _l should be determined according to the system requirements in the MIMO system in which the signal detection device is mounted on the wireless reception device. As an example, when 1 = 2 and d ₁ = 2 are set, β _p is the square of the second-order norm in the p-th row of the matrix U. “U _p ” represents the P th column vector in the U matrix, and “U _{p ,:} ” represents the P th row vector in the U matrix.

Next, the signal detection apparatus rearranges the calculated T β _p in descending order by comparing the magnitudes as shown in Expression (47).

When T = 3 in Equation (47), it is assumed that β ₁ = 0.3, β ₂ = 5.7, and β ₃ = 1.8 for a certain channel matrix H. Then, according to the equation (47), β ₁ ≦ β ₃ ≦ β ₂ → β _p1 ≦ β _p2 ≦ β _p3 , p ₁ = 1, p ₂ = 3, p ₃ = 2.

Next, the numerical values from p ₁ to p _T obtained by the magnitude comparison and rearrangement in Expression (47) are recorded as a detection order list S of T transmission signals as in Expression (48). Expressions (46) to (48) are taken as an order list generation expression.

As described above, assuming T = 3, β ₁ = 0.3, β ₂ = 5.7, and β ₃ = 1.8 for a certain channel matrix H, S = {p ₃ , p ₂ , p ₁ } = {2, 3, ₁ }. In other words, the transmission signal s ₁ is detected first, s ₃ is detected second, and s ₂ is detected third. Note that p _k (k = 1,..., T) means that the transmission signal s _pk is detected k-th.

<Regarding Step S3b>
Next, the column vector of the propagation path matrix H and the row and column vectors of the matrix G are rearranged according to the order list S determined in step S3a. Expressions (49) and (50) are mathematical expressions used for the rearrangement.

In Equation (49) and Equation (50), P corresponds to a rearrangement matrix, and its column vector is composed of e _pT ,..., E _p2 , e _p1 . Here, e _k is a column vector of T rows and 1 column, the k th element is 1 and the others are 0. A propagation path matrix after rearrangement as shown in Expression (49) or after processing equivalent to the rearrangement is represented as H ′. For example in the case of _{S = {p 3, p 2} , p 1} = {2,3,1} is _{P = [e p3, e p2} , e p1] = [e 2, e 3, e 1]. Therefore, the column vector of H is rearranged by P as shown in Expression (51).

  In this case, the multiplication of the matrices H and P does not actually require a mathematical operation, and the matrix P may be rearranged according to the order list S and the column vectors of H are rearranged. That is, even when step S3b is actually implemented, the H column vectors may be rearranged according to the list S. For matrix G, both rows and columns are reordered according to equation (50).

<Regarding Step S3c>
Next, in step S3b, the matrix G ′ in which rows and columns are rearranged for the matrix G is decomposed to derive an upper triangular matrix R. Also, using the upper triangular matrix R, the matrix H ′ in which the column vectors are rearranged is orthogonalized to generate a matrix Q. The process of decomposing the matrix G ′ to derive the upper triangular matrix R is expressed by Expression (52).

There are several methods for deriving the upper triangular matrix R as shown in equation (52). For example, Gaxpy Cholesky decomposition method or Outer Product Cholesky decomposition method. What kind of decomposition method to use is determined based on implementation considerations. Further, the matrix Q is generated by orthogonalization according to the equation (53), where q _t (t = 1, 2,... T) is the order from the left in the column vector.

That is, using the equation (53), the column vector of the matrix H ′ is processed in the order from the left to the right as in the equation (53), and the obtained result is defined as the matrix Q.

<Regarding Step S3d>
Next, the column vector y is calculated using the complex conjugate transpose of the matrix Q calculated in step S3c, and the received vector x is filtered by Expression (54).

Here, s ′ represents a matrix in which the order of the elements of the transmission signal vector s is rearranged by the matrix ^PT . V represents the synthesis of the noise component vector and the interference component vector after the linear filtering process. The column vector y includes a column vector v obtained by multiplying the matrix R and the column vector s ′ and synthesizing the noise component and the interference component.

<About Step S3e>
Next, using the upper triangular structure of R, T transmission signals are sequentially detected by backward substitution. The calculated column vector y can be written for each element as shown in Equation (55).

In Equation (55), r _{k, k} , r _{k, i} , v _k (k = T,..., 1) represent elements in the matrix R and the vector v, respectively. In the backward substitution process, the following three expressions (56), (57), and (58) are calculated from k = T to k = 1 (that is, k = T, T-1,..., 1). Repeat. Expression (56) is an operation (interference component calculation expression) for calculating an interference component for the transmission signal s _k ^′ . In this calculation, when K = T, the interference component is 0, that is, ^ m _T = 0. The subtracting the interference component ^ m _k from the k-th element y _k of the column vector Equation (57), the soft decision result ^~ s _k 'of the transmission signal ^(~ symbol indicates the tilde) is a calculation for obtaining a. The equation (58) is a process of performing a hard decision based on the cons sauce Deployment applied during modulation at the transmission side with respect to formula (57) soft decision result ^{~ s} k obtained in _'.

Then, the processing according to the above equations (56) to (58) is executed T times from k = T to k = 1, and the transmission signal vector ^ s' = [^ s ₁ ', ^ s ₂ ', ..., ^ s _T '] ^T is obtained.

<Regarding Step S3f>
Next, the T transmission signals detected are rearranged in the original transmitted spatial order (antenna order) according to the order list S and output. Using the transpose of the matrix P as shown in Expression (59), the rearrangement process of the order of the transmission signal ^ s ′ detected in Step S3e is performed. The matrix P is the same as the matrix P obtained according to the detection order list S in the process of step S3b.

For example, as in step S3b, in the case of S = {p ₃ , p ₂ , p ₁ } = { ₂ , ₃ , ₁ }, P = [e ₂ , e ₃ , e ₁ ] = [e ₃ , e ₁ , E ₂ ] ^T. Therefore, each element of ^ s ^' is rearranged by P as shown in Expression (60).

  Here, the multiplication of the matrix P and ^ s' shown in the equation (60) does not actually require a mathematical operation, and the signal detection apparatus inside the wireless reception apparatus has the matrix P according to the order list S. It only needs to have a function to sort the elements of '. After the rearrangement processing is completed, the detected transmission signal vector ^ s is output from the signal detection device, and the next processing unit of the wireless reception device performs the processing.

Next, the configuration of the signal detection device will be described.
FIG. 11 is a seventh diagram illustrating the function processing unit of the signal detection device.
FIG. 12 is an eighth diagram illustrating the function processing unit of the signal detection device.
FIG. 13 is a ninth diagram illustrating the function processing unit of the signal detection device.
First, in FIG. 11, function processing units denoted by reference numerals 31 to 36 correspond to function processing units that perform processes corresponding to the above-described steps S3a to S3f, respectively. Here, the function processing unit means a circuit group in the signal detection device or a program group executed by the device. Reference numeral 37 represents a readable / writable storage device or an information pipeline (wiring).

Reference numeral 31 denotes a detection order determination processing unit (Ordering). The detection order determination processing unit 31 reads or receives the propagation path matrix H and the coefficient α from the storage device (or pipeline) 37, and performs an arithmetic process to the order list S, the matrix G, the inverse matrix U of the upper triangular matrix R, and the inverse matrix. The value of β _{k obtained} by raising the _l- th norm in the k-th row of U to the power of d ₁ is written to the storage device 37 (or output to the pipeline). As shown in FIG. 12, the configuration of the detection order determination processing unit 31 is further divided into 31a and 31b. Reference numeral 31a denotes a matrix G calculation processing unit (G Computation). 31a reads or receives the propagation path matrix H and the coefficient α from the storage device (or pipeline) 37, calculates the matrix G according to the equation (43), and records it in the storage device 37 (or outputs it to the pipeline). To do). Reference numeral 31b denotes an order list determination processing unit (S Determination). The order list determination processing unit 31b reads or receives the matrix G from the storage device (or pipeline) 37, generates the signal detection order list S according to the equations (46) to (48), and generates the signal detection order list S. And the inverse matrix U of the upper triangular matrix R and the value of β _{k obtained} by raising the _l- th norm in the k-th row of the inverse matrix U to the d ₁ power are written in the storage device 37 (or output to the pipeline).

  Reference numeral 32 denotes a channel matrix vector rearrangement processing unit (Column & Row Exchange). The propagation path matrix vector rearrangement processing unit 32 reads or receives the signal detection order list S, the propagation path matrix H, and the matrix G from the storage device (or pipeline) 37, and the propagation path matrix H and the propagation path matrix H according to the signal detection order list S. After rearranging the matrix G, the results H ′ and G ′ are written into the storage device 37 (or output to the pipeline).

  Reference numeral 33 denotes a matrix R / matrix Q generator (R, Q Generation). The matrix R / matrix Q generation unit 33 reads or receives the matrix H ′ matrix G from the storage device (or pipeline) 37, derives the matrix R by the processing according to the equation (4), and further derives the matrix R by the equation (53). The matrix Q is calculated by orthogonalizing H ′. They are written into the storage device 37 (or output to the pipeline).

Reference numeral 34 denotes a filtering processing unit (Q ^H Filtering). The filtering processing unit 34 reads or receives the matrix Q and the received signal vector x from the storage device (or pipeline) 37, calculates the vector y by multiplying the complex conjugate transpose of Q and x, and stores it in the storage device. Write to 37 (or output to pipeline).

Reference numeral 35 denotes a backward substitution processing unit (Back Substitution). The backward substitution processing unit 35 reads or receives the column vector y and the matrix R from the storage device (or pipeline) 37, calculates the detected transmission signal vector ^ s' by the backward substitution calculation process, and detects the detected transmission signal vector ^ s ^′ is written to the storage device 37 (or output to the pipeline). As shown in FIG. 13, the backward substitution processing unit 35 further includes functional processing units of an interference component calculation processing unit (Interference Computation) 35a, a subtraction processing unit (subtractor) 35b, and a quantization processing unit (Quantiztion) 35c. Yes. Until From k = T a k = 1, is detected in the order of 'the elements of ^ s _T' detect signal vector ^ s each functional processing unit with T times in FIG. 13 from to ^ s 1 _'. Then, the interference component calculation processing unit 35a reads or receives r _{k, i} and ^ s _i ′ (i = k + 1, k + 2,..., T) from the storage device (or pipeline) 37, and performs interference according to the equation (56). The component ^ _mk is calculated and sent to the subtraction processing unit 35b. The subtraction processing section 35b is or receives read the k-th element y _k column vectors y from a storage device (or pipeline) 37, soft decision detection signal by subtracting the interference component ^ m _k from the element y _k calculating a ^~ s _k ', and sends it to the quantization processing unit 35c. Then, the quantization processing unit 35c makes a hard decision based on the constellation applied at the time of modulation on the transmission side with respect ^to the soft decision detection signal ˜s _k ′ that has received the input, and the hard decision detection signal ^ s _k ′. Is written into the storage device 37 (or output to the pipeline).

  Reference numeral 36 denotes an order rearrangement processing unit (Row Exchange). The order rearrangement processing unit 36 reads ^ s 'and the order list S from the storage device (or pipeline) 37, rearranges ^ s' according to the order list S, and then transmits the transmission signal vector ^ s as a result. Output from the detection device.

<Example 4>
Next, Example 4 will be described. The fourth embodiment is a modification of the second embodiment.
As in the first embodiment, it is assumed that the input to the signal detection device in the wireless reception device is the propagation path matrix H, the coefficient α, and the reception signal vector x, and the signal output through the signal detection processing according to the present embodiment is the detection signal. When ^ s, the signal detection device is
(Step S4a) With respect to T elements s = [s ₁ , s ₂ ,..., S _T ] in the transmission signal vector s, the order of signal detection is simultaneously determined, and the order list S To record.
(Step S4b) Next, the signal detection apparatus rearranges the row and column vectors of the propagation path matrices H and G according to the order list S, and calculates the matrix H ′ and the matrix G ′.
(Step S4c) The lower triangular matrix R is derived from the matrix G ′ in which the row vector and the column vector are rearranged, and the lower triangular matrix R is used to orthogonalize the matrix H ′ in which the column vector is rearranged, and the matrix Q Is generated.
(Step S4d) The received vector x is filtered using the complex conjugate transpose of the matrix Q.
(Step S4e) Using the lower triangular structure of the lower triangular matrix R, T transmission signals are sequentially detected by forward substitution.
(Step S4f) According to the list S, the detected T transmission signals are rearranged in the original transmitted spatial order (antenna order) and output.

Here, the signal detection apparatus repeatedly calculates only the process 2e, but the other processes 2a to 2d and 2f need only be executed once.

The matrix decomposition of step S4c described above is a process performed to decompose a Hermitian matrix A (that is, A ^H = A) of a certain T row and T column to derive a lower triangular matrix R of T row and T column, It can be represented by Formula (61).

Note that the outline of the processing of (Step S4a) to (Step S4f) described above is the same as that of (Step S2a) to (Step S2f), but differs from the second embodiment mainly in the details of the processing of Step S4a.
Next, details of the above-described processes of (Step S4a) to (Step S4f) will be described.
<About Step S4a>
For the T elements s = [s ₁ , s ₂ ,..., S _T ] in the transmission signal vector s, the respective signal detection orders are simultaneously determined and recorded in the list S. Then, the matrix G is calculated by the equation (62) using the propagation path matrix H defined as the equation (1).

Here, the coefficient α = σ _w / σ _s , where σ _w and σ _s represent the variance of the noise component and the variance of the transmission signal, respectively. If the values of σ _w and σ _s are not known, it is possible to estimate them and obtain the coefficient α using the estimated values. Also, the coefficient α can be set to other values according to the requirements of the MIMO system. For example, the coefficient α = 0 is set. When the coefficient α = 0, G = H ^H H.

  Next, the matrix G calculated by the equation (62) is decomposed as in the equation (4) and expressed using the lower triangular matrix R. Expression (63) is an expression obtained by decomposing the matrix G and using the lower triangular matrix R.

  There are several methods for decomposing the matrix G using the lower triangular matrix R as shown in the equation (63), for example, Gaxpy Cholesky decomposition method, Outer Product Cholesky decomposition method and the like. The specific decomposition method to be used should be determined based on implementation considerations.

  Next, the signal detection device calculates an inverse matrix U of the lower triangular matrix R using Expression (64).

Then, the signal detection device calculates β _p by multiplying the _l- th norm in the p-th row of the matrix U to the d ₁ power using Expression (65). Here, l and d _l should be determined according to the system requirements in the MIMO system in which the signal detection device is mounted on the wireless reception device. As an example, when 1 = 2 and d ₁ = 2 are set, β _p is the square of the second-order norm in the p-th row of the matrix U. “U _p ” represents the P th column vector in the U matrix, and “U _{p ,:} ” represents the P th row vector in the U matrix.

Next, the signal detection apparatus sorts the calculated T β _p in descending order by comparing the magnitudes as shown in Expression (66).

When T = 3 in the equation (66), it is assumed that β ₁ = 0.3, β ₂ = 5.7, and β ₃ = 1.8 for a certain channel matrix H. Then, according to the equation (66), β ₁ ≦ β ₃ ≦ β ₂ → β _p1 ≦ β _p2 ≦ β _p3 , p ₁ = 1, p ₂ = 3, p ₃ = 2.

Next, the numerical values from p ₁ to p _T obtained by the magnitude comparison and rearrangement in Expression (66) are recorded as a detection order list S of T transmission signals as in Expression (67). Expressions (65) to (67) are taken as an order list generation expression.

As described above, assuming T = 3, β ₁ = 0.3, β ₂ = 5.7, and β ₃ = 1.8 for a certain channel matrix H, S = {p ₁ , p ₂ , p ₃ } = {1, _{3, 2} }. In other words, the transmission signal s ₁ is detected first, s ₃ is detected second, and s ₂ is detected third. Note that p _k (k = 1,..., T) means that the transmission signal s _pk is detected k-th.

<Regarding Step S4b>
Next, the column vector of the propagation path matrix H and the row and column vectors of the matrix G are rearranged according to the order list S determined in step S4a. Expressions (68) and (69) are mathematical expressions used for the rearrangement.

In Equation (68) and Equation (69), P corresponds to a rearrangement matrix, and its column vector is composed of e _p1 , e _{p2 ,.} Here, e _k is a column vector of T rows and 1 column, the k th element is 1 and the others are 0. A propagation path matrix after rearrangement as shown in Expression (68) or after processing equivalent to the rearrangement is expressed as H ′. For example in the case of _{S = {p 1, p 2} , p 3} = {1,3,2} is _{P = [e p1, e p2} , e p3] = [e 1, e 3, e 2]. Therefore, the column vector of H is rearranged by P as shown in Expression (70).

  In this case, the multiplication of the matrices H and P does not actually require a mathematical operation, and the matrix P may be rearranged according to the order list S and the column vectors of H are rearranged. That is, even when step S4b is actually implemented, the H column vectors may be rearranged according to the list S. For matrix G, both rows and columns are reordered according to equation (69).

<About Step S4c>
Next, in step S4b, the matrix G ′ in which rows and columns are rearranged for the matrix G is decomposed to derive a lower triangular matrix R. Also, using the lower triangular matrix R, the matrix H ′ in which the column vectors are rearranged is orthogonalized to generate a matrix Q. The process of decomposing the matrix G ′ to derive the lower triangular matrix R is expressed by Expression (71).

There are several methods for deriving the lower triangular matrix R as shown in Equation (71). For example, Gaxpy Cholesky decomposition method or Outer Product Cholesky decomposition method. What kind of decomposition method to use is determined based on implementation considerations. Further, the matrix Q is generated by orthogonalization according to the equation (72), where q _t (t = T, T−1,..., 1) is the order from the left in the column vector.

That is, using the equation (72), the column vector of the matrix H ′ is processed in the order from right to left as in the equation (72), and the obtained result is set as the matrix Q.

<Regarding Step S4d>
Next, the column vector y is calculated using the complex conjugate transpose of the matrix Q calculated in step S4c, and the received vector x is filtered by the equation (73).

Here, s ′ represents a matrix in which the order of the elements of the transmission signal vector s is rearranged by the matrix ^PT . V represents the synthesis of the noise component vector and the interference component vector after the linear filtering process. The column vector y includes a column vector v obtained by multiplying the matrix R and the column vector s ′ and synthesizing the noise component and the interference component.

<About Step S4e>
Next, using the lower triangular structure of R, T transmission signals are sequentially detected by forward substitution. The calculated column vector y can be written for each element as shown in equation (74).

In the equation (74), r _{k, k} , r _{k, i} , v _k (k = T,..., 1) represent elements in the matrix R and the vector v, respectively. In the forward substitution process, the following three operations (75), (76), and (77) are repeated from k = 1 to k = T (that is, k = 1, 2,..., T). Do. Expression (75) is an operation (interference component calculation expression) for calculating an interference component for the transmission signal s _k ^′ . In this calculation, when K = 1, the interference component is 0, that is, ^ m ₁ = 0. The subtracting the interference component ^ m _k from the k-th element y _k of the column vector Equation (76), the soft decision result ^~ s _k 'of the transmission signal ^(~ symbol indicates the tilde) is a calculation for obtaining a. The equation (77) is a process of performing a hard decision based on the cons sauce Deployment applied during modulation at the transmission side with respect to formula (76) soft decision result ^{~ s} k obtained in _'.

Then, the processing according to the above equations (75) to (77) is executed T times from k = 1 to k = T, and the transmission signal vector ^ s' = [^ s ₁ ', ^ s ₂ ', ..., ^ s _T '] ^T is obtained.

<Regarding Step S4f>
Next, the T transmission signals detected are rearranged in the original transmitted spatial order (antenna order) according to the order list S and output. Using the transpose of the matrix P as shown in Expression (78), the rearrangement process of the order of the transmission signal ^ s ′ detected in Step S4e is performed. The matrix P is the same as the matrix P obtained according to the detection order list S in the process of step S4b.

For example, similarly to step S4b, in the case of S = {p ₁ , p ₂ , p ₃ } = { ₁ , ₃ , ₂ }, P = [e ₁ , e ₃ , e ₂ ] = [e ₁ , e ₃ , E ₂ ] ^T. Therefore, each element of ^ s ^' is rearranged by P as shown in Expression (79).

  Here, the multiplication of the matrix P and ^ s' shown in the equation (79) does not actually require a mathematical operation, and the signal detection apparatus inside the wireless reception apparatus has the matrix P according to the order list S. It only needs to have a function to sort the elements of '. After the rearrangement processing is completed, the detected transmission signal vector ^ s is output from the signal detection device, and the next processing unit of the wireless reception device performs the processing.

Next, the configuration of the signal detection device will be described.
FIG. 14 is a tenth diagram illustrating the function processing unit of the signal detection device.
FIG. 15 is an eleventh diagram illustrating the function processing unit of the signal detection device.
FIG. 16 is a twelfth diagram illustrating the function processing unit of the signal detection device.
First, in FIG. 41, function processing units denoted by reference numerals 41 to 46 correspond to function processing units that perform processes corresponding to the above-described steps S4a to S4f, respectively. Here, the function processing unit means a circuit group in the signal detection device or a program group executed by the device. Reference numeral 47 represents a readable / writable storage device or information pipeline (wiring).

Reference numeral 41 denotes a detection order determination processing unit (Ordering). The detection order determination processing unit 41 reads or receives the propagation path matrix H and the coefficient α from the storage device (or pipeline) 47, and performs an arithmetic process to the order list S, the matrix G, the inverse matrix U of the lower triangular matrix R, and the inverse matrix. The value of β _{k obtained} by multiplying the _l- th norm in the k-th row of U to the power of d ₁ is written to the storage device 47 (or output to the pipeline). As shown in FIG. 15, the configuration of the detection order determination processing unit 41 is further divided into 41a and 41b. 41a is a matrix G calculation processing part (G Computation). The matrix G calculation processing unit 41a reads or receives the propagation path matrix H and the coefficient α from the storage device (or pipeline) 47, calculates the matrix G according to the equation (61), and records it in the storage device 47 ( Or output to the pipeline). Reference numeral 41b denotes an order list determination processing unit (S Determination). The order list determination processing unit 41b reads or receives the matrix G from the storage device (or pipeline) 47, generates the signal detection order list S according to the equations (65) to (67), and generates the signal detection order list S. And the inverse matrix U of the lower triangular matrix R and the value of β _{k obtained} by raising the _l- th norm in the k-th row of the inverse matrix U to the d ₁ power are written in the storage device 47 (or output to the pipeline).

  Reference numeral 42 denotes a channel matrix vector rearrangement processing unit (Column & Row Exchange). The propagation path matrix vector rearrangement processing unit 42 reads or receives the signal detection order list S, the propagation path matrix H, and the matrix G from the storage device (or pipeline) 47, and the propagation path matrix H and the propagation path matrix H according to the signal detection order list S. After rearranging the matrix G, the results H ′ and G ′ are written into the storage device 47 (or output to the pipeline).

  Reference numeral 43 denotes a matrix R / matrix Q generator (R, Q Generation). The matrix R / matrix Q generation unit 43 reads or receives the matrix H ′ matrix G from the storage device (or pipeline) 47, derives the matrix R by the processing according to the equation (4), and further derives the matrix R by the equation (72). The matrix Q is calculated by orthogonalizing H ′. They are written into the storage device 47 (or output to the pipeline).

Reference numeral 44 denotes a filtering processing unit (Q ^H Filtering). The filtering processing unit 44 reads or receives the matrix Q and the received signal vector x from the storage device (or pipeline) 47, calculates the vector y by multiplying the complex conjugate transpose of Q and x, and stores it in the storage device. Write to 47 (or output to pipeline).

Reference numeral 45 denotes a forward substitution processing unit (Back Substitution). The forward substitution processing unit 45 reads or receives the column vector y and the matrix R from the storage device (or pipeline) 47, calculates the detected transmission signal vector ^ s' by the forward substitution calculation process, and detects the detected transmission signal vector ^ s ^′ is written to the storage device 47 (or output to the pipeline). As shown in FIG. 16, the forward substitution processing unit 45 further includes functional processing units of an interference component calculation processing unit (Interference Computation) 45a, a subtraction processing unit (subtractor) 45b, and a quantization processing unit (Quantiztion) 45c. Yes. Until From k = 1 for k = T, is detected in the order of 'the elements of ^ s _1' detection signal vector ^ s each functional processing unit with T times in FIG. 16 to ^ s T _'. Then, the interference component calculation processing unit 45a reads or receives r _{k, i} and ^ s _i ′ (i = 1, 2,..., K−1) from the storage device (or pipeline) 47, and formula (75) The interference component _{circumflex over (m) _} is calculated in accordance with the above and sent to the subtraction processing unit 45b. The subtraction processing unit 45b or receive reading k-th element y _k column vectors y from a storage device (or pipeline) 47, soft decision detection signal by subtracting the interference component ^ m _k from the element y _k calculating a ^~ s _k ', and sends it to the quantization processing unit 45 c. Then, the quantization processing unit 45c performs a hard decision based on the constellation applied at the time of modulation on the transmission side with respect ^to the soft decision detection signal ˜s _k ′ that has received the input, and the hard decision detection signal ^ s _k ′. Is written to the storage device 47 (or output to the pipeline).

  Reference numeral 46 denotes an order rearrangement processing unit (Row Exchange). The order rearrangement processing unit 46 reads ^ s 'and the order list S from the storage device (or pipeline) 47, rearranges ^ s' according to the order list S, and then transmits the transmission signal vector ^ s as a result. Output from the detection device.

In the prior art, signal detection order determination and signal extraction vector generation for T transmission signals are performed by T pseudo inverse matrix operations, and transmission signals are detected in order using the extraction vectors. However, in the third and fourth embodiments of the present invention, without first calculating the pseudo inverse matrix, the detection order is first determined by a novel method, and then the column vectors are rearranged by triangulation. The system transfer coefficient matrix is triangulated, and the system transfer coefficient matrix is orthogonalized using the triangular matrix. Finally, using the triangular structure of the transfer coefficient matrix, T transmission signals are detected by backward substitution or forward substitution, and are rearranged in the original transmitted spatial order and output.
Thus, according to the third and fourth embodiments described above, it is not necessary to perform a pseudo inverse matrix operation, and main calculation amounts are a detection order determination operation, a QR decomposition operation, and a backward or forward substitution operation. . Accordingly, the required calculation amount is extremely small as compared with the conventional SIC method. Therefore, it is possible to provide a signal detection device for a wireless reception device that has a smaller amount of processing operation and a smaller required operation circuit scale than conventional ones.

  Further, according to the third and fourth embodiments of the present invention, the required storage capacity is small because there is no calculation of the pseudo inverse matrix. Thereby, the required storage device capacity of the signal detection device of the wireless reception device can be reduced.

  Further, according to the third and fourth embodiments of the present invention, since the required arithmetic circuit scale and the storage device are small, it is possible to easily reduce the size and weight of the signal detection device of the wireless reception device.

  Further, according to the third and fourth embodiments of the present invention, instead of T pseudo inverse matrix operations, the detection order is determined by a novel method, and then column vectors are rearranged by triangulation. The system transfer coefficient matrix is triangulated, and the system transfer coefficient matrix is orthogonalized using the triangular matrix. Finally, T transmission signals are detected by backward substitution or forward substitution using the triangular structure of the transfer coefficient matrix. For this reason, the processing delay is greatly reduced. As a result, even when the number of transmission antennas is large, real-time processing is possible without increasing the clock frequency in the arithmetic circuit. That is, the processing delay of the signal detection device of the wireless reception device can be reduced.

  Further, according to the third and fourth embodiments of the present invention, the required power consumption is proportional to the required arithmetic circuit scale, the operation clock frequency, and the like, so that the power consumption of the present invention is higher than that of the conventional MMSE-SIC method. In the signal detection device of the wireless reception device, power consumption is reduced. Therefore, it is possible to realize a long operating time of the MIMO system operated by the battery.

  According to the third and fourth embodiments of the present invention, in the economical implementation of the signal detection device of the radio reception device in hardware and software, the above-described effects reduce the manufacturing cost and make it suitable for mass production. It will be.

  Further, according to the third and fourth embodiments of the present invention, ZF-SIC and MMSE-SIC can be easily switched by simply setting the coefficient α. It is also possible to set other values depending on the propagation path conditions.

  The most important features of the third and fourth embodiments of the present invention are: 1. A new signal detection order determination method has been devised. 2. ZF-SIC and MMSE-SIC can be easily switched by setting coefficient α, and other values can be set according to propagation path conditions. 3. Invented a method for triangulation and orthogonalization based on the system transfer coefficient matrix. 4. Invented a method of signal detection by backward or forward substitution using the triangular structure of the system transfer coefficient matrix. 5. Proposed a method of rearranging the elements of the transmission signal detected by backward or forward substitution and the column vector and matrix G of the system transfer coefficient matrix H according to the order determined in the above (1.). This is to devise a method of combining (1.), (2.), (3.), (4.) and (5.).

  Note that the signal detection device of the above-described wireless reception device has a computer system therein. The process described above is stored in a computer-readable recording medium in the form of a program, and the above process is performed by the computer reading and executing this program. Here, the computer-readable recording medium means a magnetic disk, a magneto-optical disk, a CD-ROM, a DVD-ROM, a semiconductor memory, or the like. Alternatively, the computer program may be distributed to the computer via a communication line, and the computer that has received the distribution may execute the program.

  The program may be for realizing a part of the functions described above. Furthermore, what can implement | achieve the function mentioned above in combination with the program already recorded on the computer system, and what is called a difference file (difference program) may be sufficient.

It is a 1st figure which shows the structure of a MIMO-OFDM system. It is a 2nd figure which shows the structure of a MIMO-OFDM system. It is a 1st figure which shows the structure of a MIMO-Single system. It is a 2nd figure which shows the structure of a MIMO-Single system. It is a 1st figure which shows the function process part of a signal detection apparatus. It is a 2nd figure which shows the function process part of a signal detection apparatus. It is a 3rd figure which shows the function process part of a signal detection apparatus. It is a 4th figure which shows the function process part of a signal detection apparatus. It is a 5th figure which shows the function process part of a signal detection apparatus. It is a 6th figure which shows the function process part of a signal detection apparatus. It is a 7th figure which shows the function process part of a signal detection apparatus. It is an 8th figure which shows the function process part of a signal detection apparatus. It is a 9th figure which shows the function process part of a signal detection apparatus. It is a 10th figure which shows the function process part of a signal detection apparatus. It is an 11th figure which shows the function process part of a signal detection apparatus. It is a 12th figure which shows the function process part of a signal detection apparatus.

Explanation of symbols

11, 21, 31, 41 ... detection order determination processing unit 12, 22, 32, 42 ... propagation path matrix vector rearrangement processing unit 13, 23, 33, 43 ... matrix R / matrix Q generation unit 14, 24, 34, 44 ... Filtering processing unit 15, 35 ... Backward substitution processing unit 16, 26, 36, 46 ... Order rearrangement processing unit 17, 27, 37, 47 ... Storage device 25, 45 ... Forward substitution processing unit

Claims (22)

A radio signal separation method in a radio reception apparatus that performs signal detection of a received signal using a propagation path matrix H, a predetermined coefficient α, and a received signal vector x in a MIMO (Multiple Input Multiple Output) system,
For T elements in the transmission signal vector s of the signal transmitted by the wireless transmission device, the order of signal detection is determined by the correlation between the received power calculated from the propagation path matrix H and the propagation path. Decide, record in the order list,
The row vector and the column vector of the matrix G calculated from G = H ^H H + α ² I using the complex conjugate transpose of the channel matrix H, the channel matrix H, the coefficient α, and the unit matrix I are the ordered list. Sort according to S,
Deriving a triangular matrix R from the matrix in which the matrix G is rearranged, generating a matrix Q by orthogonalizing the matrix in which the column vector of the propagation path matrix H is rearranged using the triangular matrix,
Filtering the received vector x using the complex conjugate transpose of the matrix Q;
A process of performing a backward substitution process or a forward substitution process on the reception vector filtered using the triangular matrix R, and performing a hard decision on the received signal one by one in the order of the signal detection, and another process based on the hard-decided received signal By repeating the process of removing the interference component to the received signal, the T transmission signals are sequentially detected,
The radio signal separation method, wherein the detected T transmission signals are rearranged in the original transmitted spatial order according to the order list and output. A radio signal separation method in a radio reception apparatus that performs signal detection of a received signal using a propagation path matrix H, a predetermined coefficient α, and a received signal vector x in a MIMO (Multiple Input Multiple Output) system,
For T elements in the transmission signal vector s of the signal transmitted by the wireless transmission device, the order of signal detection is determined by the correlation between the received power calculated from the propagation path matrix H and the propagation path. A detection order determination process that simultaneously determines and records in the order list;
The row vector and the column vector of the matrix G calculated from G = H ^H H + α ² I using the complex conjugate transpose of the channel matrix H, the channel matrix H, the coefficient α, and the unit matrix I are the ordered list. A reordering process for reordering according to S;
A matrix that derives an upper triangular matrix R from a matrix obtained by rearranging the matrix G, and generates a matrix Q by orthogonalizing the matrix obtained by rearranging the column vectors of the propagation path matrix H using the upper triangular matrix R. R / matrix Q generation processing;
A filtering process for filtering the received vector x using a complex conjugate transpose of the matrix Q;
Using the filtering result and the upper triangular structure of the upper triangular matrix R , a backward substitution process is performed on the filtered received vector, and a hard decision is performed on the received signal one by one in the order of the signal detection. A backward substitution process for sequentially detecting the T transmission signals by repeating the process of removing interference components from other received signals by the received signal ,
An order rearrangement process for outputting the detected T transmission signals in accordance with the order list and rearranging them in the original transmitted spatial order; and
A radio signal separation method comprising: The detection order determination process generates the order list according to the matrix G and an order list generation formula,
The rearrangement processing outputs a matrix H ′ as a result of rearranging the propagation path matrix H and a matrix G ′ as a result of rearrangement of the matrix G;
In the matrix R / matrix Q generation process, an upper triangular matrix R is derived from the matrix G ′ using a triangular matrix calculation formula, and the matrix H ′ is orthogonalized using the upper triangular matrix R to generate a matrix Q. Output,
The filtering process calculates a vector y by multiplying the complex conjugate transpose of the matrix Q and the received signal vector x,
The backward substitution process calculates a detected transmission signal vector by a backward substitution calculation process using the column vector y and the upper triangular matrix R, sequentially detects T elements of the detected transmission signal vector, and detects interference. An interference component is calculated according to a component calculation formula, and a soft decision detection signal is calculated by subtracting the interference component from the k th element y _{k of the} column vector y. Based on the constellation applied at the time of modulation, a hard decision is made to calculate a hard decision detection signal,
The radio signal according to claim 2, wherein the order rearrangement process outputs the rearrangement result after rearranging the detected transmission signal vectors obtained by the backward substitution process according to the order list. Separation method. In the detection order determination process, the matrix G is decomposed to derive an upper triangular matrix, the _l- th norm in the p-th row of the inverse matrix U of the upper triangular matrix is calculated to the power of d _l , and β _p is calculated. Rearranging the β _p values calculated for the inverse matrix U of the triangular matrix in ascending order, and generating each numerical value obtained by the rearrangement as an ordered list;
The rearrangement processing outputs a matrix H ′ as a result of rearranging the propagation path matrix H and a matrix G ′ as a result of rearrangement of the matrix G;
In the matrix R / matrix Q generation process, an upper triangular matrix R is derived from the matrix G ′ using a triangular matrix calculation formula, and the matrix H ′ is orthogonalized using the upper triangular matrix R to generate a matrix Q. Output,
The filtering process calculates a vector y by multiplying the complex conjugate transpose of the matrix Q and the received signal vector x,
The backward substitution process calculates a detected transmission signal vector by a backward substitution calculation process using the column vector y and the upper triangular matrix R, sequentially detects T elements of the detected transmission signal vector, and detects interference. An interference component is calculated according to a component calculation formula, and a soft decision detection signal is calculated by subtracting the interference component from the k th element y _{k of the} column vector y. Based on the constellation applied at the time of modulation, a hard decision is made to calculate a hard decision detection signal,
The radio signal according to claim 2, wherein the order rearrangement process outputs the rearrangement result after rearranging the detected transmission signal vectors obtained by the backward substitution process according to the order list. Separation method. A radio signal separation method in a radio reception apparatus that performs signal detection of a received signal using a propagation path matrix H, a predetermined coefficient α, and a received signal vector x in a MIMO (Multiple Input Multiple Output) system,
For T elements in the transmission signal vector s of the signal transmitted by the wireless transmission device, the order of signal detection is determined by the correlation between the received power calculated from the propagation path matrix H and the propagation path. A detection order determination process that simultaneously determines and records in the order list;
The row vector and the column vector of the matrix G calculated from G = H ^H H + α ² I using the complex conjugate transpose of the channel matrix H, the channel matrix H, the coefficient α, and the unit matrix I are the ordered list. A reordering process for reordering according to S;
A matrix that derives a lower triangular matrix R from a matrix obtained by rearranging the matrix G, and generates a matrix Q by orthogonalizing the matrix obtained by rearranging the column vectors of the propagation path matrix H using the lower triangular matrix R. R / matrix Q generation processing;
A filtering process for filtering the received vector x using a complex conjugate transpose of the matrix Q;
Using the filtering result and the lower triangular structure of the lower triangular matrix R , a forward substitution process is performed on the filtered received vector, and a hard decision and a hard decision are performed on the received signal one by one in the order of the signal detection. Forward substitution processing for sequentially detecting the T transmission signals by repeating the processing of removing interference components from other received signals by the received signals ,
An order rearrangement process for outputting the detected T transmission signals in accordance with the order list and rearranging them in the original transmitted spatial order; and
A radio signal separation method comprising: The detection order determination process generates the order list according to the matrix G and an order list generation formula,
The rearrangement processing outputs a matrix H ′ as a result of rearranging the propagation path matrix H and a matrix G ′ as a result of rearrangement of the matrix G;
In the matrix R / matrix Q generation process, a lower triangular matrix R is derived from the matrix G ′ using a triangular matrix calculation formula, and the matrix H ′ is orthogonalized using the lower triangular matrix R to generate a matrix Q. Output,
The filtering process calculates a vector y by multiplying the complex conjugate transpose of the matrix Q and the received signal vector x,
The forward substitution processing calculates a detected transmission signal vector by forward substitution calculation processing using the column vector y and the lower triangular matrix R, detects T elements of the detected transmission signal vector in order, and detects interference An interference component is calculated according to a component calculation formula, and a soft decision detection signal is calculated by subtracting the interference component from the k th element y _{k of the} column vector y. Based on the constellation applied at the time of modulation, a hard decision is made to calculate a hard decision detection signal,
The wireless signal according to claim 5, wherein the order rearrangement process outputs the rearrangement result after rearranging the detected transmission signal vectors obtained by the forward substitution process according to the order list. Separation method. In the detection order determination process, the matrix G is decomposed to derive a lower triangular matrix, the _l- th norm in the p-th row of the inverse matrix U of the lower triangular matrix is calculated to the power of d _l , and β _p is calculated. Rearranging the β _p values calculated for the inverse matrix U of the triangular matrix in ascending order, and generating each numerical value obtained by the rearrangement as an ordered list;
The rearrangement processing outputs a matrix H ′ as a result of rearranging the propagation path matrix H and a matrix G ′ as a result of rearrangement of the matrix G;
In the matrix R / matrix Q generation process, a lower triangular matrix R is derived from the matrix G ′ using a triangular matrix calculation formula, and the matrix H ′ is orthogonalized using the lower triangular matrix R to generate a matrix Q. Output,
The filtering process calculates a vector y by multiplying the complex conjugate transpose of the matrix Q and the received signal vector x,
The forward substitution processing calculates a detected transmission signal vector by forward substitution calculation processing using the column vector y and the lower triangular matrix R, detects T elements of the detected transmission signal vector in order, and detects interference An interference component is calculated according to a component calculation formula, and a soft decision detection signal is calculated by subtracting the interference component from the k th element y _{k of the} column vector y. Based on the constellation applied at the time of modulation, a hard decision is made to calculate a hard decision detection signal,
The wireless signal according to claim 5, wherein the order rearrangement process outputs the rearrangement result after rearranging the detected transmission signal vectors obtained by the forward substitution process according to the order list. Separation method. A radio receiving apparatus that performs signal detection of a received signal using a propagation path matrix H, a predetermined coefficient α, and a received signal vector x in a MIMO (Multiple Input Multiple Output) system,
For T elements in the transmission signal vector s of the signal transmitted by the wireless transmission device, the order of signal detection is determined by the correlation between the received power calculated from the propagation path matrix H and the propagation path. Means to determine and record in the order list;
The row vector and the column vector of the matrix G calculated from G = H ^H H + α ² I using the complex conjugate transpose of the channel matrix H, the channel matrix H, the coefficient α, and the unit matrix I are the ordered list. Means for sorting according to S;
Means for deriving a triangular matrix R from the matrix in which the matrix G is rearranged, and generating a matrix Q by orthogonalizing the matrix in which the column vector of the propagation path matrix H is rearranged using the triangular matrix;
Means for filtering the received vector x using a complex conjugate transpose of the matrix Q;
A process of performing a backward substitution process or a forward substitution process on the reception vector filtered using the triangular matrix R, and performing a hard decision on the received signal one by one in the order of the signal detection, and another reception by the hard-decided received signal Means for sequentially detecting the T transmission signals by repeating the process of removing interference components to the signal;
Means for rearranging and outputting the detected T transmission signals in the original transmitted spatial order according to the order list;
A radio receiving apparatus comprising: A radio receiving apparatus that performs signal detection of a received signal using a propagation path matrix H, a predetermined coefficient α, and a received signal vector x in a MIMO (Multiple Input Multiple Output) system,
For T elements in the transmission signal vector s of the signal transmitted by the wireless transmission device, the order of signal detection is determined by the correlation between the received power calculated from the propagation path matrix H and the propagation path. A detection order determining means for simultaneously determining and recording in the order list;
The row vector and the column vector of the matrix G calculated from G = H ^H H + α ² I using the complex conjugate transpose of the channel matrix H, the channel matrix H, the coefficient α, and the unit matrix I are the ordered list. Reordering means for reordering according to S;
A matrix that derives an upper triangular matrix R from a matrix obtained by rearranging the matrix G, and generates a matrix Q by orthogonalizing the matrix obtained by rearranging the column vectors of the propagation path matrix H using the upper triangular matrix R. R / matrix Q generation means;
Filtering means for filtering the received vector x using a complex conjugate transpose of the matrix Q;
Using the filtering result and the upper triangular structure of the upper triangular matrix R , a backward substitution process is performed on the filtered received vector, and a hard decision is performed on the received signal one by one in the order of the signal detection. Repetitive substitution means for sequentially detecting the T transmission signals by repeating the process of removing interference components from other received signals by the received signals .
Order rearrangement means for rearranging and outputting the detected T transmission signals according to the order list in the original transmitted spatial order;
A radio receiving apparatus comprising: The detection order determining means generates the order list according to the matrix G and an order list generation formula,
The rearranging means outputs a matrix H ′ as a result of rearranging the propagation path matrix H and a matrix G ′ as a result of rearranging the matrix G,
The matrix R / matrix Q generating means derives an upper triangular matrix R from the matrix G ′ using a triangular matrix calculation formula, and orthogonalizes the matrix H ′ using the upper triangular matrix R to generate a matrix Q. Output,
The filtering means calculates a vector y by multiplying the complex conjugate transpose of the matrix Q and the received signal vector x,
The backward substitution means calculates a detected transmission signal vector by backward substitution arithmetic processing using the column vector y and the upper triangular matrix R, sequentially detects T elements of the detected transmission signal vector, and performs interference. An interference component is calculated according to a component calculation formula, and a soft decision detection signal is calculated by subtracting the interference component from the k th element y _{k of the} column vector y. Based on the constellation applied at the time of modulation, a hard decision is made to calculate a hard decision detection signal,
The wireless reception according to claim 9, wherein the order rearranging means outputs the rearrangement result after rearranging the detected transmission signal vectors obtained by the backward substitution process according to the order list. apparatus. The detection order determining means calculates the β _p by decomposing the matrix G to derive an upper triangular matrix, calculating the _l- th norm in the p-th row of the inverse matrix U of the upper triangular matrix to the power of d _l , Rearranging the β _p values calculated for the inverse matrix U of the triangular matrix in ascending order, and generating each numerical value obtained by the rearrangement as an ordered list;
The rearranging means outputs a matrix H ′ as a result of rearranging the propagation path matrix H and a matrix G ′ as a result of rearranging the matrix G,
The matrix R / matrix Q generating means derives an upper triangular matrix R from the matrix G ′ using a triangular matrix calculation formula, and orthogonalizes the matrix H ′ using the upper triangular matrix R to generate a matrix Q. Output,
The filtering means calculates a vector y by multiplying the complex conjugate transpose of the matrix Q and the received signal vector x,
The backward substitution means calculates a detected transmission signal vector by backward substitution arithmetic processing using the column vector y and the upper triangular matrix R, sequentially detects T elements of the detected transmission signal vector, and performs interference. An interference component is calculated according to a component calculation formula, and a soft decision detection signal is calculated by subtracting the interference component from the k th element y _{k of the} column vector y. Based on the constellation applied at the time of modulation, a hard decision is made to calculate a hard decision detection signal,
The wireless reception according to claim 9, wherein the order rearranging means outputs the rearrangement result after rearranging the detected transmission signal vectors obtained by the backward substitution process according to the order list. apparatus. A radio receiving apparatus that performs signal detection of a received signal using a propagation path matrix H, a predetermined coefficient α, and a received signal vector x in a MIMO (Multiple Input Multiple Output) system,
For T elements in the transmission signal vector s of the signal transmitted by the wireless transmission device, the order of signal detection is determined by the correlation between the received power calculated from the propagation path matrix H and the propagation path. A detection order determining means for simultaneously determining and recording in the order list;
The row vector and the column vector of the matrix G calculated from G = H ^H H + α ² I using the complex conjugate transpose of the channel matrix H, the channel matrix H, the coefficient α, and the unit matrix I are the ordered list. Reordering means for reordering according to S;
A matrix that derives a lower triangular matrix R from a matrix obtained by rearranging the matrix G, and generates a matrix Q by orthogonalizing the matrix obtained by rearranging the column vectors of the propagation path matrix H using the lower triangular matrix R. R / matrix Q generation means;
Filtering means for filtering the received vector x using a complex conjugate transpose of the matrix Q;
Using the filtering result and the lower triangular structure of the lower triangular matrix R , a forward substitution process is performed on the filtered received vector, and a hard decision and a hard decision are performed on the received signal one by one in the order of the signal detection. Forward substitution means for sequentially detecting the T transmission signals by repeating the process of removing interference components from other received signals by the received signals ,
Order rearrangement means for rearranging and outputting the detected T transmission signals according to the order list in the original transmitted spatial order;
A radio receiving apparatus comprising: The detection order determining means generates the order list according to the matrix G and an order list generation formula,
The rearranging means outputs a matrix H ′ as a result of rearranging the propagation path matrix H and a matrix G ′ as a result of rearranging the matrix G,
The matrix R / matrix Q generation means derives a lower triangular matrix R from the matrix G ′ using a triangular matrix calculation formula, and orthogonalizes the matrix H ′ using the lower triangular matrix R to generate a matrix Q. Output,
The filtering means calculates a vector y by multiplying the complex conjugate transpose of the matrix Q and the received signal vector x,
The forward substitution means calculates a detection transmission signal vector by forward substitution calculation processing using the column vector y and the lower triangular matrix R, sequentially detects T elements of the detection transmission signal vector, and detects interference. An interference component is calculated according to a component calculation formula, and a soft decision detection signal is calculated by subtracting the interference component from the k th element y _{k of the} column vector y. Based on the constellation applied at the time of modulation, a hard decision is made to calculate a hard decision detection signal,
The said order rearrangement means is provided with these after rearranging the detection transmission signal vector obtained by the said forward substitution process according to the said order list, The rearrangement result is provided. Wireless receiver. The detection order determining means calculates the β _p by decomposing the matrix G to derive a lower triangular matrix, computing the _l- th norm in the p-th row of the inverse matrix U of the lower triangular matrix to the power of d _l , and Rearranging the β _p values calculated for the inverse matrix U of the triangular matrix in ascending order, and generating each numerical value obtained by the rearrangement as an ordered list;
The rearranging means outputs a matrix H ′ as a result of rearranging the propagation path matrix H and a matrix G ′ as a result of rearranging the matrix G,
The matrix R / matrix Q generation means derives a lower triangular matrix R from the matrix G ′ using a triangular matrix calculation formula, and orthogonalizes the matrix H ′ using the lower triangular matrix R to generate a matrix Q. Output,
The filtering means calculates a vector y by multiplying the complex conjugate transpose of the matrix Q and the received signal vector x,
The forward substitution means calculates a detection transmission signal vector by forward substitution calculation processing using the column vector y and the lower triangular matrix R, sequentially detects T elements of the detection transmission signal vector, and detects interference. An interference component is calculated according to a component calculation formula, and a soft decision detection signal is calculated by subtracting the interference component from the k th element y _{k of the} column vector y. Based on the constellation applied at the time of modulation, a hard decision is made to calculate a hard decision detection signal,
The said order rearrangement means is provided with these after rearranging the detection transmission signal vector obtained by the said forward substitution process according to the said order list, The rearrangement result is provided. Wireless receiver. A program that is executed by a computer of a wireless reception device that performs signal detection of a received signal using a propagation path matrix H, a predetermined coefficient α, and a received signal vector x in a MIMO (Multiple Input Multiple Output) system,
For T elements in the transmission signal vector s of the signal transmitted by the wireless transmission device, the order of signal detection is determined by the correlation between the received power calculated from the propagation path matrix H and the propagation path. Processing to determine and record in the order list;
The row vector and the column vector of the matrix G calculated from G = H ^H H + α ² I using the complex conjugate transpose of the channel matrix H, the channel matrix H, the coefficient α, and the unit matrix I are the ordered list. Reordering according to S;
A process of generating a matrix Q by deriving a triangular matrix R from a matrix in which the matrix G is rearranged and orthogonalizing a matrix in which a column vector of the channel matrix H is rearranged using the triangular matrix;
Filtering received vector x using a complex conjugate transpose of matrix Q;
A process of performing a backward substitution process or a forward substitution process on the reception vector filtered using the triangular matrix R, and performing a hard decision on the received signal one by one in the order of the signal detection, and another reception by the hard-decided received signal A process of sequentially detecting the T transmission signals by repeating a process of removing an interference component to the signal;
A process of rearranging the detected T transmission signals in the original transmitted spatial order according to the order list and outputting them;
A program that causes a computer to execute. A program that is executed by a computer of a wireless reception device that performs signal detection of a received signal using a propagation path matrix H, a predetermined coefficient α, and a received signal vector x in a MIMO (Multiple Input Multiple Output) system,
For T elements in the transmission signal vector s of the signal transmitted by the wireless transmission device, the order of signal detection is determined by the correlation between the received power calculated from the propagation path matrix H and the propagation path. A detection order determination process that simultaneously determines and records in the order list;
The row vector and the column vector of the matrix G calculated from G = H ^H H + α ² I using the complex conjugate transpose of the channel matrix H, the channel matrix H, the coefficient α, and the unit matrix I are the ordered list. A reordering process for reordering according to S;
A matrix that derives an upper triangular matrix R from a matrix obtained by rearranging the matrix G, and generates a matrix Q by orthogonalizing the matrix obtained by rearranging the column vectors of the propagation path matrix H using the upper triangular matrix R. R / matrix Q generation processing;
A filtering process for filtering the received vector x using a complex conjugate transpose of the matrix Q;
Using the filtering result and the upper triangular structure of the upper triangular matrix R , a backward substitution process is performed on the filtered received vector, and a hard decision is performed on the received signal one by one in the order of the signal detection. A backward substitution process for sequentially detecting the T transmission signals by repeating the process of removing interference components from other received signals by the received signal ,
An order rearrangement process for outputting the detected T transmission signals in accordance with the order list and rearranging them in the original transmitted spatial order; and
A program that causes a computer to execute. In the detection order determination process, the order list is generated according to the matrix G and the order list generation formula,
In the rearrangement process, a matrix H ′ resulting from rearranging the propagation path matrix H and a matrix G ′ resulting from rearranging the matrix G are output,
In the matrix R / matrix Q generation processing, an upper triangular matrix R is derived from the matrix G ′ using a triangular matrix calculation formula, and the matrix H ′ is orthogonalized using the upper triangular matrix R to generate a matrix Q. Output
In the filtering process, a vector y is calculated by multiplying the complex conjugate transpose of the matrix Q and the received signal vector x,
In the backward substitution processing, a detection transmission signal vector is calculated by backward substitution calculation processing using the column vector y and the upper triangular matrix R, and T elements of the detection transmission signal vector are sequentially detected, An interference component is calculated according to an interference component calculation formula, and a soft decision detection signal is calculated by subtracting the interference component from the k-th element y _{k of the} column vector y. The hard decision is performed based on the constellation applied at the time of modulation in to calculate the hard decision detection signal,
17. The order rearrangement process according to claim 16, wherein after the detected transmission signal vectors obtained by the backward substitution process are rearranged according to the order list, each process of outputting the rearrangement result is executed by a computer. Program. In the detection order determination process, the matrix G is decomposed to derive an upper triangular matrix, the _l- th norm in the p-th row of the inverse matrix U of the upper triangular matrix is raised to the d ₁ power to calculate β _p , Rearranging the values of β _p calculated for the inverse matrix U of the upper triangular matrix in ascending order, and generating each numerical value obtained by the rearrangement as an ordered list,
In the rearrangement process, a matrix H ′ resulting from rearranging the propagation path matrix H and a matrix G ′ resulting from rearranging the matrix G are output,
In the matrix R / matrix Q generation processing, an upper triangular matrix R is derived from the matrix G ′ using a triangular matrix calculation formula, and the matrix H ′ is orthogonalized using the upper triangular matrix R to generate a matrix Q. Output
In the filtering process, a vector y is calculated by multiplying the complex conjugate transpose of the matrix Q and the received signal vector x,
In the backward substitution processing, a detection transmission signal vector is calculated by backward substitution calculation processing using the column vector y and the upper triangular matrix R, and T elements of the detection transmission signal vector are sequentially detected, An interference component is calculated according to an interference component calculation formula, and a soft decision detection signal is calculated by subtracting the interference component from the k-th element y _{k of the} column vector y. The hard decision is performed based on the constellation applied at the time of modulation in to calculate the hard decision detection signal,
17. The order rearrangement process according to claim 16, wherein after the detected transmission signal vectors obtained by the backward substitution process are rearranged according to the order list, each process of outputting the rearrangement result is executed by a computer. Program. A program that is executed by a computer of a wireless reception device that performs signal detection of a received signal using a propagation path matrix H, a predetermined coefficient α, and a received signal vector x in a MIMO (Multiple Input Multiple Output) system,
For T elements in the transmission signal vector s of the signal transmitted by the wireless transmission device, the order of signal detection is determined by the correlation between the received power calculated from the propagation path matrix H and the propagation path. A detection order determination process that simultaneously determines and records in the order list;
The row vector and the column vector of the matrix G calculated from G = H ^H H + α ² I using the complex conjugate transpose of the channel matrix H, the channel matrix H, the coefficient α, and the unit matrix I are the ordered list. A reordering process for reordering according to S;
A matrix that derives a lower triangular matrix R from a matrix obtained by rearranging the matrix G, and generates a matrix Q by orthogonalizing the matrix obtained by rearranging the column vectors of the propagation path matrix H using the lower triangular matrix R. R / matrix Q generation processing;
A filtering process for filtering the received vector x using a complex conjugate transpose of the matrix Q;
Using the filtering result and the lower triangular structure of the lower triangular matrix R , a forward substitution process is performed on the filtered received vector, and a hard decision and a hard decision are performed on the received signal one by one in the order of the signal detection. Forward substitution processing for sequentially detecting the T transmission signals by repeating the processing of removing interference components from other received signals by the received signals ,
An order rearrangement process for outputting the detected T transmission signals in accordance with the order list and rearranging them in the original transmitted spatial order; and
A program that causes a computer to execute. In the detection order determination process, the order list is generated according to the matrix G and the order list generation formula,
In the rearrangement process, a matrix H ′ resulting from rearranging the propagation path matrix H and a matrix G ′ resulting from rearranging the matrix G are output,
In the matrix R / matrix Q generation process, a lower triangular matrix R is derived from the matrix G ′ using a triangular matrix calculation formula, and the matrix H ′ is orthogonalized using the lower triangular matrix R to generate a matrix Q. Output
In the filtering process, a vector y is calculated by multiplying the complex conjugate transpose of the matrix Q and the received signal vector x,
In the forward substitution process, a detected transmission signal vector is calculated by a forward substitution calculation process using the column vector y and the lower triangular matrix R, and T elements of the detected transmission signal vector are sequentially detected, An interference component is calculated according to an interference component calculation formula, and a soft decision detection signal is calculated by subtracting the interference component from the k-th element y _{k of the} column vector y. The hard decision is performed based on the constellation applied at the time of modulation in to calculate the hard decision detection signal,
20. In the order rearrangement process, after rearranging the detected transmission signal vectors obtained by the forward substitution process according to the order list, each process of outputting the rearrangement result is executed by a computer. Program. In the detection order determination process, the matrix G is decomposed to derive a lower triangular matrix, and the _l- th norm in the p-th row of the inverse matrix U of the lower triangular matrix is calculated to the power of d _l to calculate β _p , Rearranging the β _p values calculated for the inverse matrix U of the lower triangular matrix in ascending order, and generating each numerical value obtained by the rearrangement as an ordered list,
In the rearrangement process, a matrix H ′ resulting from rearranging the propagation path matrix H and a matrix G ′ resulting from rearranging the matrix G are output,
In the matrix R / matrix Q generation process, a lower triangular matrix R is derived from the matrix G ′ using a triangular matrix calculation formula, and the matrix H ′ is orthogonalized using the lower triangular matrix R to generate a matrix Q. Output
In the filtering process, a vector y is calculated by multiplying the complex conjugate transpose of the matrix Q and the received signal vector x,
In the forward substitution process, a detected transmission signal vector is calculated by a forward substitution calculation process using the column vector y and the lower triangular matrix R, and T elements of the detected transmission signal vector are sequentially detected, An interference component is calculated according to an interference component calculation formula, and a soft decision detection signal is calculated by subtracting the interference component from the k-th element y _{k of the} column vector y. The hard decision is performed based on the constellation applied at the time of modulation in to calculate the hard decision detection signal,
20. In the order rearrangement process, after rearranging the detected transmission signal vectors obtained by the forward substitution process according to the order list, each process of outputting the rearrangement result is executed by a computer. Program.   A computer-readable recording medium recording the program according to any one of claims 15 to 21.

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