JP3619821B2 - Transmitting apparatus and transmitting method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a transmission device and a transmission method, and in particular, can be applied to a transmission device and a transmission method that transmit transmission data encoded using a turbo encoder.
[0002]
[Prior art]
Conventionally, there is a turbo code as an error correction coding method, which is adopted as a standard in 3GPP (see, for example, Patent Document 1). This turbo code is characterized in that a very good error rate characteristic can be obtained as compared with other error correction methods. There has been proposed a transmission apparatus that improves transmission efficiency by performing adaptive modulation according to communication quality on transmission data encoded by such a turbo encoder.
[0003]
[Patent Document 1]
JP 2002-217748 A
[0004]
[Problems to be solved by the invention]
However, in the conventional transmission apparatus and transmission method, even if transmission data encoded by a turbo encoder is adaptively modulated, a good error rate characteristic can be obtained by turbo encoding, and transmission efficiency is improved by adaptive modulation. Therefore, there is a problem in that it is impossible to make the best use of the characteristic that the error rate can be improved, and it is impossible to achieve both the error rate characteristics and the transmission efficiency.
[0005]
The present invention has been made in view of the above point, and when transmitting transmission data after turbo encoding by adaptive modulation, by obtaining a synergistic effect of turbo encoding and adaptive modulation, error rate characteristics and It is an object of the present invention to provide a transmission device and a transmission method capable of further achieving compatibility with transmission efficiency.
[0006]
[Means for Solving the Problems]
The transmission device of the present invention, encoding means for turbo encoding transmission data to output systematic bit data and parity bit data; When the modulation method of both the systematic bit data and the parity bit data is independently adaptively modulated and the communication quality is better than the communication quality when the parity bit data modulation method is changed And a modulation means for changing the modulation method of the systematic bit data, A transmission unit that transmits the systematic bit data and the parity bit data modulated by the modulation unit is employed.
[0009]
According to this configuration, The systematic bit data and parity bit data can be modulated separately depending on the channel quality, so if the channel quality deteriorates, the systematic bit data is converted into a modulation method with a small multi-level error. In case of an error, it is possible to perform error correction with parity bits transmitted by a modulation method having a higher number of multi-values than systematic bit data, and retransmit the transmitted data. By reducing the number of times, it is possible to further improve the error rate characteristics and the transmission efficiency.
[0011]
further, According to this configuration, the adaptive modulation in the systematic bit data is performed when the channel quality is better than the channel quality at the time of performing the adaptive modulation in the parity bit data. The data modulation method can be changed to a modulation method with a small multi-level number, and the systematic bit data can be retransmitted by preventing the error rate property of the systematic bit data from deteriorating before the error rate property of the parity bit data is degraded. The number of requests can be reduced.
[0012]
The transmission apparatus according to the present invention employs a configuration in which, when the transmission data is required to have good communication quality, the modulation means modulates systematic bit data and parity bit data by a modulation method with a small number of multivalues. .
[0013]
Further, the transmission data in the transmission apparatus of the present invention adopts a configuration that is information used for communication control or retransmission information.
[0014]
According to these configurations, when transmitting transmission data that requires good communication quality, both systematic bit data and parity bit data are independently modulated using a modulation scheme with a small number of multi-values. So, it prevents the error rate characteristics of systematic bit data from degrading, and when an error occurs, error correction can be performed using parity bit data modulated by a modulation method with a small number of multi-values. It is possible to reliably prevent a decrease in error rate characteristics of transmission data that requires good communication quality.
[0015]
The transmission means in the transmission apparatus of the present invention comprises a spreading means for spreading the modulated systematic bit data and parity bit data, and an orthogonal frequency division multiplexing means for orthogonal frequency division multiplexing of the spread signal. take.
[0016]
According to this configuration, it is possible to achieve both improvement in error rate characteristics and improvement in transmission efficiency in the OFDM-CDMA communication system.
[0017]
The transmission apparatus of the present invention employs a configuration in which the spreading factor of the spreading means is set to “1” and the code multiplexing number of the transmission signal is set to “1”.
[0018]
According to this configuration, it is possible to improve both the error rate characteristics and the transmission efficiency in the OFDM communication system.
[0019]
The base station apparatus of the present invention employs a configuration including any one of the transmission apparatuses described above. Moreover, the communication terminal apparatus of this invention takes the structure which comprises one of said transmission apparatuses.
[0020]
According to these configurations, it is possible to further improve both the error rate characteristics and the transmission efficiency in communication between the base station apparatus and the communication terminal apparatus.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
The gist of the present invention is to adaptively modulate systematic bit data and parity bit data independently. In other words, when the line quality deteriorates, the systematic bit data is converted into a modulation scheme with a small multi-level number to prevent the error rate characteristics from being lowered, and when an error occurs, the multi-level number is higher than the systematic bit data. In other words, error correction is performed with parity bits transmitted by a modulation method with a large number of modulations, and the number of retransmissions of transmission data is reduced.
[0024]
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0025]
(Embodiment 1)
FIG. 1 is a diagram showing a configuration of transmitting apparatus 100 according to Embodiment 1 of the present invention. The transmission apparatus 100 includes a control unit 101, an encoding unit 102, a modulation unit 103, a parallel / serial (hereinafter referred to as "P / S") conversion unit 105, a spreader 106, and a serial / parallel (hereinafter referred to as "S / P"). And a transforming unit 107, an inverse discrete Fourier transforming unit (IDFT) 108, and an antenna 109. The modulation unit 103 is mainly configured by a first modulation unit 103a and a second modulation unit 103b.
[0026]
The control unit 101 determines communication quality using an RSSI (Received Signal Strength Indicator) signal, and outputs a control signal corresponding to the communication quality to the second modulation unit 103b. That is, if the RSSI signal is equal to or greater than the threshold value, a control signal for setting the modulation method to a modulation method with a large number of multiple values such as 16QAM is output to the second modulation unit 103b. On the other hand, if the RSSI signal is less than the threshold value, a control signal for setting the modulation scheme to a modulation scheme with a small number of multivalues such as QPSK is output to the second modulation section 103b. In addition, when the communication unit is currently communicating and the result of determination in the control unit 101 is that the currently used modulation scheme is continuously used, the control unit 101 does not output a control signal to the second modulation unit 103b. . Here, the modulation scheme with a large number of multi-values is a modulation scheme with a large number of constellation mapping points on the IQ plane.
[0027]
The encoding unit 102 is a turbo encoder, for example, and outputs a part of the input transmission data to the first modulation unit 103a without encoding as a part of the input transmission data, and also outputs the remaining part of the input transmission data. Is subjected to recursive convolutional coding and output as parity bit data to the second modulator 103b. Note that the encoding unit 102 may be an encoder other than a turbo encoder. Details of the encoding unit 102 will be described later.
[0028]
The first modulation unit 103 a has a modulation scheme fixed to QPSK, performs QPSK modulation on the systematic bit data input from the encoding unit 102, and outputs the result to the P / S conversion unit 105.
[0029]
Based on the control signal input from the control unit 101, the second modulation unit 103b performs adaptive modulation such as QPSK modulation or 16QAM modulation on the parity bit data input from the encoding unit 102, and performs P / S. The data is output to the conversion unit 105. A method for changing the modulation method will be described later.
[0030]
The P / S conversion unit 105, which is a transmission means, converts the systematic bit data input from the first modulation unit 103a and the parity bit data input from the second modulation unit 103b from parallel data to serial data, and thereby spreads To 106.
[0031]
The spreader 106 serving as a spreading unit multiplies the transmission data input from the S / P conversion unit 107 by the spreading code and outputs the result to the S / P conversion unit 107. When transmitting by the OFDM-CDMA communication method, the spreading code with a spreading factor other than “1” is multiplied. When transmitting by the OFDM communication method, the spreading code with a spreading factor of “1” is used. Multiply.
[0032]
The S / P conversion unit 107 converts the transmission data input from the spreader 106 from serial data to parallel data, and outputs the converted data to the inverse discrete Fourier transform unit 108.
[0033]
The inverse discrete Fourier transform unit 108 generates transmission data by converting it into a sum of N subcarriers of different frequencies (N is an arbitrary natural number), and transmits the generated transmission data from the antenna 109. When transmitting by the OFDM-CDMA communication method, the signal multiplexing number of each subcarrier is a multiplexing number other than “1”, the code multiplexing number of the transmission signal is other than “1”, and transmission is performed by the OFDM communication method. In this case, the signal multiplexing number of each subcarrier is “1”, and the code multiplexing number of the transmission signal is “1”. The S / P conversion unit 107 and the inverse discrete Fourier transform unit 108 constitute an orthogonal frequency division multiplexing unit.
[0034]
Next, details of the configuration of the encoding unit 102 will be described with reference to FIG. The encoding unit 102 mainly includes an interleaver 201, a convolutional encoding unit 202, and a convolutional encoding unit 203.
[0035]
The interleaver 201 interleaves the transmission data and outputs it to the convolutional coding unit 203.
[0036]
The convolutional coding unit 202 performs recursive convolutional coding on a part of the transmission data and outputs the result to the second modulation unit 103b. The output from the convolutional coding unit 202 is parity bit data.
[0037]
The convolutional coding unit 203 performs recursive convolutional coding on a part of the transmission data input from the interleaver 201 and outputs the result to the second modulation unit 103b. The output from the convolutional coding unit 203 is parity bit data. Part of the transmission data input to the encoding unit 102 is output as it is without being encoded. This output is systematic bit data.
[0038]
Next, the operation of transmitting apparatus 100 will be described using FIG. The transmission data is encoded by the encoding unit 102 (step (hereinafter referred to as “ST”) 301), the systematic bit data is output to the first modulation unit 103a, and the parity bit data is output to the second modulation unit. 103b. The systematic bit data input to first modulation section 103a is QPSK modulated and output to P / S conversion section 105 (ST302).
[0039]
Based on the RSSI signal, control unit 101 determines whether or not the RSSI signal is equal to or greater than a threshold value (ST303). If the RSSI signal is equal to or greater than the threshold value, the control unit 101 determines that the communication quality is good. From 101, a control signal for setting the modulation scheme to 16QAM is output to the second modulation section 103b. Second modulation section 103b sets the modulation scheme to 16QAM based on the control signal for setting the modulation scheme input from control section 101 (ST304). The parity bit data input to second modulation section 103b is 16QAM modulated and output to P / S conversion section 105 (ST305).
[0040]
On the other hand, when the RSSI signal is less than the threshold value in ST303, control unit 101 outputs a control signal for setting the modulation scheme to QPSK to second modulation unit 103b. Second modulation section 103b sets the modulation scheme to QPSK based on the control signal for setting the modulation scheme input from control section 101 (ST306). The parity bit data input to second modulation section 103b is QPSK modulated and output to P / S conversion section 105 (ST307). P / S conversion section 105 converts systematic bit data and parity bit data from parallel data to serial data, and outputs the result to spreader 106 (ST308). Next, the transmission data is multiplied by a spreading code in spreader 106 (ST309), further subjected to S / P conversion processing and inverse discrete Fourier transform processing, which are orthogonal frequency division multiplexing processing, and transmitted from antenna 109. (ST310).
[0041]
In such a transmission apparatus, when the line quality deteriorates, the systematic bit data is changed to a modulation method with a small multi-value number to prevent the error rate characteristic from being lowered, and when an error occurs, the systematic bit data In addition, error correction can be performed with parity bits transmitted by a modulation scheme having a large number of multi-values, and the number of retransmissions of transmission data is reduced.
[0042]
On the other hand, when the line quality is improved, the systematic bit data can be made a modulation scheme with a large multi-level number to improve the error rate characteristics, and when an error occurs, the systematic bit data Can perform error correction with parity bits transmitted with a modulation scheme that has a small number of multi-values but does not degrade the error rate characteristics, and reduces the number of retransmissions of transmission data.
[0043]
Thus, according to the transmission apparatus and transmission method of the present embodiment, systematic bit data and parity bit data are independently modulated, and the modulation method of parity bit data is adaptively changed according to communication quality. Therefore, it is possible to achieve both improvement in error rate characteristics and improvement in transmission efficiency. In addition, since the systematic bit data and the parity bit data modulated independently are subjected to the orthogonal frequency division multiplexing after being spread, the error rate characteristics of the transmission data can be further improved.
[0044]
In the present embodiment, only parity bit data is adaptively modulated according to communication quality, but only systematic bit data may be adaptively modulated according to communication quality.
[0045]
(Embodiment 2)
FIG. 4 is a diagram showing a configuration of transmitting apparatus 400 according to Embodiment 2 of the present invention. The modulation unit 402 in the present embodiment mainly includes a first modulation unit 402a and a second modulation unit 402b. The present embodiment is characterized in that the modulation schemes in both the first modulation section 402a and the second modulation section 402b are adaptively modulated according to the communication quality. 1 is different from FIG. 1 in that a control signal from the control unit 401 is input to the first modulation unit 402a, and the description of the same configuration as in the first embodiment is omitted.
[0046]
The control unit 401 determines communication quality using the RSSI signal and outputs a control signal corresponding to the communication quality to the first modulation unit 402a and the second modulation unit 402b. When setting the modulation method, the control unit 401 sets a threshold value α for setting the modulation method for modulating systematic bit data and a threshold for setting the modulation method for modulating parity bit data. Two types of threshold values, the value β, are used. That is, if the RSSI signal is equal to or greater than the threshold value α, a control signal for setting the modulation method to a modulation method having a large number of multivalues such as 16QAM is output to the first modulation unit 402a, and the RSSI signal is set to the threshold value β If it is above, the control signal which sets a modulation system to a modulation system with many multilevels, such as QPSK, is output to the 2nd modulation | alteration part 402b.
[0047]
On the other hand, if the RSSI signal is less than the threshold value α, the control unit 401 outputs a control signal for setting the modulation method to a modulation method with a small number of multivalues such as QPSK to the first modulation unit 402a. If it is less than the threshold value β, a control signal for setting the modulation method to a modulation method with a small number of multivalues such as QPSK is output to the second modulation section 402b. Note that when the communication unit is currently communicating and the result of determination in the control unit 401 is that the currently used modulation scheme is to be used continuously, the control unit 401 transmits the control signal to the first modulation unit 402a and the second modulation unit 402a. Is not output to the modulation unit 402b. Details of the configuration of the control unit 401 will be described later.
[0048]
Based on the control signal input from control section 401, first modulation section 402a performs QPSK modulation or 16QAM modulation on the systematic bit data input from encoding section 102 and outputs the result to P / S conversion section 105. To do.
[0049]
Based on the control signal input from the control unit 401, the second modulation unit 402b performs adaptive modulation such as QPSK modulation or 16QAM modulation on the parity bit data input from the encoding unit 102, and performs P / S. The data is output to the conversion unit 105. A method for changing the modulation method will be described later.
[0050]
Next, details of the configuration of the control unit 401 will be described with reference to FIG. The control unit 401 is mainly composed of a first determination control unit 501 and a second determination control unit 502.
[0051]
The first determination control unit 501 outputs a control signal for setting the modulation scheme to 16QAM to the first modulation unit 402 if the RSSI signal is equal to or greater than a preset threshold value α. On the other hand, if the RSSI signal is less than the threshold value α, a control signal for setting the modulation scheme to QPSK is output to the first modulation section 402a.
[0052]
The second determination control unit 502 outputs a control signal for setting the modulation scheme to 16QAM to the first modulation unit 402 if the RSSI signal is equal to or greater than a preset threshold value β. On the other hand, if the RSSI signal is less than threshold value β, a control signal for setting the modulation scheme to QPSK is output to second modulation section 402b.
[0053]
Since the systematic bit data requires better communication quality than the parity bit data, the threshold value α is set to an RSSI value higher than the threshold value β. As a result, the systematic bit data is always modulated by the same modulation scheme as the parity bit data or a modulation scheme having a smaller number of multi-values than the parity bit data modulation scheme.
[0054]
Next, the operation of transmitting apparatus 400 will be described using FIG. The transmission data is encoded by encoding section 102 (ST601), systematic bit data is output to first modulation section 402a, and parity bit data is output to second modulation section 402b.
[0055]
Based on the RSSI signal, control unit 401 determines whether or not the RSSI signal is greater than or equal to threshold value α (ST602). If the RSSI signal is greater than or equal to threshold value α, communication quality is assumed to be good. The control unit 401 outputs a control signal for setting the modulation scheme to 16QAM to the first modulation unit 402a. First modulation section 402a sets the modulation scheme to 16QAM based on the control signal for setting the modulation scheme input from control section 401 (ST603). The systematic bit data input to first modulation section 402a is 16QAM modulated and output to P / S conversion section 105 (ST604).
[0056]
On the other hand, when the RSSI signal is less than the threshold value α in ST602, the control unit 401 outputs a control signal for setting the modulation method to QPSK. First modulation section 402a sets the modulation scheme to QPSK based on the control signal for setting the modulation scheme input from control section 401 (ST605). The systematic bit data input to second modulation section 402b is QPSK modulated and output to P / S conversion section 105 (ST606).
[0057]
Next, based on the RSSI signal, control section 401 determines whether or not the RSSI signal is equal to or greater than threshold value β (ST607). If the RSSI signal is equal to or greater than threshold value β, the communication quality is good. As an example, the control unit 401 outputs a control signal for setting the modulation scheme to 16QAM to the second modulation unit 402b. Second modulation section 402b sets the modulation scheme to 16QAM based on the control signal for setting the modulation scheme input from control section 401 (ST608). The parity bit data input to second modulation section 402b is 16QAM modulated and output to P / S conversion section 105 (ST609).
[0058]
On the other hand, in ST607, when the RSSI signal is less than threshold β, control section 401 outputs a control signal for setting the modulation scheme to QPSK to second modulation section 402b. Second modulation section 402b sets the modulation scheme to QPSK based on the control signal for setting the modulation scheme input from control section 401 (ST610). The parity bit data input to second modulation section 402b is QPSK modulated and output to P / S conversion section 105 (ST611). P / S conversion section 105 converts systematic bit data and parity bit data from parallel to serial and outputs them to spreader 106 (ST612). Next, the transmission data is multiplied by the spreading code in the spreader 106 (ST613), further subjected to orthogonal frequency division multiplexing processing, S / P conversion processing and inverse discrete Fourier transform processing, and transmitted from the antenna 109. (ST614).
[0059]
As described above, according to the transmission apparatus and the transmission method of the present embodiment, in addition to the effects of the first embodiment, since the systematic bit data is adaptively modulated according to the communication quality, the error rate characteristic is further improved. Both improvement in transmission efficiency can be achieved. In addition, the control unit 401 compares the RSSI signal with different threshold values in the case of systematic bit data and in the case of parity bit data, so that error rate characteristics can be improved and transmitted flexibly in response to changes in communication quality. It is possible to achieve both improvement in efficiency.
[0060]
In this embodiment, the control unit 401 uses different values for the threshold value α and the threshold value β used when determining whether or not the communication quality is equal to or higher than the RSSI signal. The threshold value α and the threshold value β may be set to the same value, or the threshold value α may be smaller than the threshold value β.
[0061]
(Embodiment 3)
FIG. 7 is a diagram showing a configuration of transmitting apparatus 700 according to Embodiment 3 of the present invention. The present embodiment is characterized in that the modulation scheme in both the first modulation section 103a and the second modulation section 103b is always a modulation scheme with a small number of multi-values such as QPSK. Note that portions having the same configuration as in FIG. 1 are denoted by the same reference numerals and description thereof is omitted.
[0062]
First modulation section 103 a modulates transmission data by QPSK and outputs the result to P / S conversion section 105.
[0063]
Second modulation section 103 b modulates transmission data by QPSK and outputs the result to P / S conversion section 105.
[0064]
The transmission data in the present embodiment is required to have good communication quality such as control information and retransmission information. The transmission data is not limited to control information and retransmission information, but includes data that requires good communication quality.
[0065]
Thus, according to the transmission apparatus and the transmission method of the present embodiment, systematic bit data and parity bit data are modulated independently, and the modulation method is fixedly made a modulation method with a small number of multi-values. When the transmission data requires good communication quality such as control information and retransmission information, it is possible to achieve both improvement in error rate characteristics and improvement in transmission efficiency. In addition, since the systematic bit data and the parity bit data modulated independently are subjected to the orthogonal frequency division multiplexing after being spread, the error rate characteristics of the transmission data can be further improved.
[0066]
In the present embodiment, the modulation scheme is QPSK, but is not limited to QPSK, and may be other than QPSK as long as the modulation scheme has a small number of multivalues. In addition, both the first modulation unit 103a and the second modulation unit 103b are modulated by QPSK. However, the first modulation unit 103a and the second modulation unit 103b do not necessarily have the same modulation scheme. The modulation scheme of the unit 103b may be a different modulation scheme.
[0067]
Incidentally, since systematic bit data requires better communication quality than parity bit data, when 16QAM is used as a modulation method for both systematic bit data and parity bit data, systematic bit data is converted into polar bits. There is also a method of performing the process of arranging. As a result, the systematic bit data can obtain good error rate characteristics.
[0068]
However, since the quality of 16QAM polarity bits is inferior to that of QPSK, even if systematic bits are arranged in the polarity bits, the error rate characteristics are deteriorated as compared with the first and second embodiments. In addition, since the systematic bits are arranged in the polarity bits, a special process of dividing the transmission data into two systems and arranging the transmission data in the polarity bits and the amplitude bits of 16QAM is necessary. The processing is more complicated than in the second mode. Further, although the process of arranging systematic bits in the polarity bits cannot be performed in 8PSK, QPSK, and BPSK, the first and second embodiments are not limited in the modulation scheme.
[0069]
In Embodiments 1 and 2, adaptive modulation is performed using 16QAM and QPSK. However, the present invention is not limited to this, and modulation schemes such as 8PSK and BPSK other than 16QAM and QPSK are used. Adaptive modulation may be performed. In Embodiments 1 and 2, the systematic bit data is modulated by the first modulation unit and the parity bit data is modulated by the second modulation unit. However, the present invention is not limited to this. Instead, the systematic bit and the parity bit may be modulated by one modulation unit. In the first and second embodiments, the communication quality is determined based on the RSSI signal. However, the present invention is not limited to this, and there may be a signal that can determine the communication quality in addition to the RSSI signal. For example, the communication quality may be determined by a signal other than the RSSI signal. Moreover, the transmission apparatus and transmission method in Embodiment 1 and Embodiment 2 are applicable to arbitrary communication systems such as CDMA, OFDM, OFDM-CDMA, multicarrier CDMA, and single carrier. Moreover, the transmission apparatus and the transmission method in Embodiment 1 and Embodiment 2 can be applied to a base station apparatus and a communication terminal apparatus.
[0070]
【The invention's effect】
As described above, according to the present invention, when transmission data after turbo coding is adaptively modulated and transmitted, a synergistic effect of turbo coding and adaptive modulation is obtained, so that error rate characteristics and transmission efficiency can be obtained. Can be further improved.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a transmission apparatus according to Embodiment 1 of the present invention.
FIG. 2 is a block diagram showing a configuration of an encoding unit according to Embodiment 1 of the present invention.
FIG. 3 is a flowchart showing the operation of the transmission apparatus according to Embodiment 1 of the present invention.
FIG. 4 is a block diagram showing a configuration of a transmission apparatus according to Embodiment 2 of the present invention.
FIG. 5 is a block diagram showing a configuration of a control unit according to Embodiment 2 of the present invention.
FIG. 6 is a flowchart showing the operation of the transmission apparatus according to Embodiment 2 of the present invention.
FIG. 7 is a block diagram showing a configuration of a transmission apparatus according to Embodiment 3 of the present invention.
[Explanation of symbols]
101 Control unit
102 Encoding unit
103, 402 Modulator
103a, 402a First modulation section
103b, 402b Second modulation unit
105 P / S converter

Claims (7)

Encoding means for turbo-encoding transmission data to output systematic bit data and parity bit data, and modulating both the systematic bit data and the parity bit data by independently and adaptively changing the modulation schemes In addition, when the communication quality is better than the communication quality at the time of changing the modulation method of the parity bit data, the modulation means for changing the modulation method of the systematic bit data, the systematic bit data modulated by the modulation means, and And a transmission means for transmitting the parity bit data. 2. The modulation unit according to claim 1, wherein when the transmission data is required to have good communication quality, the modulation unit modulates the systematic bit data and the parity bit data by a modulation method with a small number of multi-values. Transmitter device. The transmission apparatus according to claim 2 , wherein the transmission data is information used for communication control or retransmission information. The transmission unit, according to claim 1, characterized by comprising a diffusion means for diffusing the systematic bit data and parity bit data after the modulation, and orthogonal frequency division multiplexing means for orthogonal frequency division multiplexing signal after spreading The transmission device according to claim 3 . 5. The transmission apparatus according to claim 4, wherein a spreading factor of said spreading means is "1", and a code multiplexing number of a transmission signal is "1". A base station apparatus comprising the transmission apparatus according to any one of claims 1 to 5 . A communication terminal device comprising the transmission device according to any one of claims 1 to 5 .

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