CN102291356B - Digital radio broadcast signal transmission method - Google Patents

Abstract

The invention discloses a digital wireless broadcasting signal transmission method, which is a mixed transmission scheme of time domain and frequency domain. The digital wireless broadcasting signal transmission method of the present invention designs a low-complexity peak-to-average power ratio reduction technology for the technical problems that need to be solved in terms of signal peak-to-average power ratio and channel fading noise faced by the broadband multi-carrier digital wireless broadcasting transmission system , serial concatenated multi-bit-rate punctured convolutional coding modulation technology, signal frame time-frequency domain combined iterative separation processing technology, making the broadband multi-carrier digital wireless broadcasting system have low peak-to-average power ratio, short synchronization time, and anti-fading noise , Controllable multi-service and other advantages.

Description

A digital wireless broadcasting signal transmission method

technical field

The invention belongs to the field of wireless communication, and more specifically relates to a digital wireless broadcast signal transmission method.

Background technique

At present, television broadcasting has gradually developed from analog to digital. Digital TV wireless multimedia broadcasting transmission system, as an important part of digital TV wireless multimedia broadcasting, the development of its related technologies is closely related to people's quality of life, and therefore has received extensive attention from people. Digital TV wireless multimedia broadcasting related technologies and related industries are industries with rapid development and good market prospects in the field of communication and computer. In terms of technologies related to digital TV and digital wireless broadcasting, the current focus of various countries is how to provide low-cost, reliable and high-speed mobile implementation solutions for digital TV and digital wireless broadcasting in a complex wave propagation environment. Digital wireless broadcasting signal transmitter transmission technology is the key technology of digital TV digital wireless broadcasting system, plays a decisive role in the performance of the whole system, and is the object of everyone's key research.

Due to the rapid development of digital signal processing technology and integrated circuit technology, the system realization of Orthogonal Frequency Division Multiplexing (OFDM) technology becomes easier and easier. Because OFDM multi-carrier transmission technology has many advantages such as simple structure, high spectrum utilization rate, and anti-frequency selectivity and channel time variation, it has attracted much attention and has been deeply researched and applied in Xdsl, broadband mobile communication, broadband wireless local area network, It is widely used in many fields such as digital TV and digital wireless broadcasting.

The high peak-to-average power ratio (PAPR) of OFDM signals has high requirements on the linear range of amplifiers and digital-to-analog converters. If the linear range of the system cannot meet the signal changes, it will cause signal distortion and signal spectrum changes. , resulting in the destruction of the orthogonality between sub-channels, resulting in mutual interference and deteriorating system performance. Therefore, it is necessary to consider how to reduce the occurrence probability of high peak power signals in OFDM signals and reduce the impact of nonlinear distortion.

Channel coding is an important part of digital communication systems. With the rapid development of modern information technology, channel coding technology has become an indispensable technology in the field of modern communication. Redundant code elements are embedded in the information sequence, and channel coding technology reduces signal errors during transmission through the role of redundant code elements, thereby improving the reliability of the communication system. Serial concatenated coding is a coding scheme that enables data transfer rates close to the theoretical maximum, the Shannon limit.

In the actual communication environment, the performance of the digital TV wireless multimedia broadcasting communication system is affected by factors such as synchronization time, clock jitter, channel fading, and channel interference. The digital wireless broadcasting signal transmitter transmission method is the key technology to realize the reliable digital TV digital wireless broadcasting.

Using the digital TV wireless multimedia broadcasting transmission system to provide controllable multi-services such as free TV broadcasting, paid TV broadcasting, confidential information transmission, and multimedia value-added services is a manifestation of the new generation of digital TV wireless multimedia broadcasting transmission system meeting social needs.

Based on the above background, the present invention proposes a digital wireless broadcast signal transmission method for the actual communication environment, which can meet the needs of high data rate controllable multi-service digital TV digital wireless broadcast transmission.

For a more in-depth understanding of the patent background, please refer to the following literature:

R.V.Nee, R.Prasad. "OFDM for wireless multimedia communications". Boston: Artech House, 2000.

Y. Wu, S. Hirakawa, U.H. Reimers, and J. Whitaker. "Overview of digital television development," Proceedings of the IEEE, Special Issue on Global Digital Television: Technology and Emerging Services, pp.8-21, Jan.2006.

M.S. Richer, G. Reitmeier, T. Gurley, G.A. Jones, J. Whitaker, and R. Rast. "The ATSC digital television system," Proceedings of the IEEE, Special Issue on Global Digital Television: Technology and Emerging Services, pp.37 -43, Jan. 2006.

U.Ladebusch and C.A.Liss. "Terrestrial DVB (DVB-T): A broadcast technology for stationary portable and mobile use," Proceedings of the IEEE, Special Issue on Global Digital Television: Technology and Emerging Services, pp.183-1294, Jan. .

M. Takada and M. Saito. "Transmission systems for ISDB-T," Proceedings of the IEEE, Special Issue on Global Digital Television: Technology and Emerging Services, pp.251-256, Jan.2006.

S. Benedetto and G. Montorsi. "Iterative decoding of serially concatenated convolutional codes," Electronics Letters, pp.1186-1188, 1996.

Contents of the invention

Aiming at the problem of high data rate controllable multi-service digital TV digital wireless broadcasting, the invention proposes a digital wireless broadcasting signal transmission method.

A kind of digital wireless broadcasting signal transmission method that the present invention proposes is characterized in that it comprises the following steps:

1) The digital wireless broadcast signal transmitter converts the multimedia data stream into a bit stream through the media data processor, and uses the scrambling code sequence generated by the feedback shift register to perform scrambling processing to form an input data bit stream;

2) The digital wireless broadcast signal transmitter forms an FFT coded data block in the frequency domain by serially cascading multi-code rate punctured convolution coding of its own input data bit stream, FFT stands for Fast Discrete Fourier Transform, and the FFT coded data block length is K;

3) The digital wireless broadcast signal transmitter adopts IFFT to transform the FFT coded data block into a time-domain discrete coded data sample block D _total , and IFFT stands for Inverse Fast Discrete Fourier Transform;

4) The digital wireless broadcast signal transmitter divides the time-domain discretely coded data sample block into two blocks in sequence, the time-domain discretely coded data sample sub-block D ₁ and the time-domain discretely coded data sample sub-block D ₂ , D _total = [D ₁ , D ₂ ];

并将降峰均功率比时域离散编码数据样值块

所对应采用的生成模式信息发送给业务指标序列设置单元，其中，D^* ₁表示对时域离散编码数据样值子块D₁的各时域离散编码数据样值进行共轭运算处理而得到的时域离散编码数据样值子块；5) The digital wireless broadcast signal transmitter performs signal addition, subtraction, and conjugate operation processing on the time-domain discretely encoded data sample sub-block D ₁ and the time-domain discretely encoded data sample sub-block D ₂ through the peak-to-average power ratio adjustment unit. Re-synthesize a new time-domain discretely coded data sample block _Dnew , and the new time-domain discretely coded data sample block _Dnew is obtained by the following generation mode, generation mode 1 is _Dnew = [D ₁ , D ₂ ], generation mode 2 for ${\mathrm{D.}}_{\mathrm{new}}=[{\mathrm{D.}}_1,\sqrt{1/2}({\mathrm{D.}}_1+{\mathrm{D.}}_2)],$ Generate schema 3 as ${\mathrm{D.}}_{\mathrm{new}}=[{\mathrm{D.}}_1,\sqrt{1/2}({\mathrm{D.}}_1-{\mathrm{D.}}_2)],$ Generate schema 4 as ${\mathrm{D.}}_{\mathrm{new}}=[\sqrt{1/2}({\mathrm{D.}}_1+{\mathrm{D.}}_2),{\mathrm{D.}}_2],$ Generate schema 5 as ${\mathrm{D.}}_{\mathrm{new}}=[\sqrt{1/2}({\mathrm{D.}}_1-{\mathrm{D.}}_2),{\mathrm{D.}}_2],$ Generate schema 6 as ${\mathrm{D.}}_{\mathrm{new}}=[\sqrt{1/2}({\mathrm{D.}}_1+{\mathrm{D.}}_2),\sqrt{1/2}({\mathrm{D.}}_1-{\mathrm{D.}}_2)],$ Generation mode 7 is D _new = [D ^* ₁ , D ₂ ], generation mode 8 is ${\mathrm{D.}}_{\mathrm{new}}=[{{\mathrm{D.}}^{*}}_1,\sqrt{1/2}({{\mathrm{D.}}^{*}}_1+{\mathrm{D.}}_2)],$ Generate schema 9 as ${\mathrm{D.}}_{\mathrm{new}}=[{{\mathrm{D.}}^{*}}_1,\sqrt{1/2}({{\mathrm{D.}}^{*}}_1-{\mathrm{D.}}_2)],$ Generate schema 10 as ${\mathrm{D.}}_{\mathrm{new}}=[\sqrt{1/2}({{\mathrm{D.}}^{*}}_1+{\mathrm{D.}}_2),{\mathrm{D.}}_2],$ Generate schema 11 as ${\mathrm{D.}}_{\mathrm{new}}=[\sqrt{1/2}({{\mathrm{D.}}^{*}}_1-{\mathrm{D.}}_2),{\mathrm{D.}}_2],$ Generate schema 12 as ${\mathrm{D.}}_{\mathrm{new}}=[\sqrt{1/2}({{\mathrm{D.}}^{*}}_1+{\mathrm{D.}}_2),\sqrt{1/2}({{\mathrm{D.}}^{*}}_1-{\mathrm{D.}}_2)],$ Compare the time-domain discrete-coded data sample block D _new synthesized by 12 generation modes, and select the time-domain discrete-coded data sample block with the lowest peak-to-average power ratio

and reduce the peak-to-average power ratio time-domain discretely coded data sample block

The generated mode information correspondingly adopted is sent to the service index sequence setting unit, wherein, D ^* ₁ means that the time domain discrete coded data samples of the time domain discrete coded data sample sub-block _D1 are conjugated and processed Time-domain discretely coded data sample sub-blocks;

6) The digital wireless broadcast signal transmitter uses the training sequence as the real part sequence of the complex training sequence, and uses the service index sequence set by the service index sequence setting unit as the imaginary part sequence of the complex training sequence to form the complex training sequence in the time domain Discrete sample value block, the length of the discrete sample value block of the training sequence, service index sequence, and complex training sequence is X, and the service index sequence contains and uniquely expresses various system parameters and service mode information of the digital wireless broadcast signal transmitter;

7) The digital wireless broadcast signal transmitter repeats the discrete sample value blocks of the complex training sequence formed in the time domain for 4 consecutive times in the time domain to form a time domain embedded training sequence discrete sample value block, and the time domain embedded training sequence discrete sample value The block length is numerically equal to the length of the peak-to-average power ratio time-domain discretely encoded data sample block, that is, K=4×X;

8) The digital wireless broadcast signal transmitter directly superimposes the time-domain discrete coded data sample blocks with reduced peak-to-average power ratio and time-domain embedded training sequence discrete sample blocks to form time-domain embedded training sequence reduced peak-to-average power ratio time-domain discrete coded data Sample block, as a frame body;

9) The digital wireless broadcast signal transmitter uses the cyclic prefix as a guard interval, that is, inserts the frame header into the time domain, embeds the training sequence, reduces the peak-to-average power ratio, and the discretely encoded data sample block in the time domain, that is, the frame body, to form a signal frame. The length of the cyclic prefix is C;

10) The digital wireless broadcast signal transmitter uses a square root raised cosine roll-off filter to shape the signal pulse of the signal frame;

11) The digital wireless broadcast signal transmitter up-converts the baseband signal to the carrier to form a radio frequency signal and transmits it to the wireless channel in the air;

12) The digital wireless broadcast signal receiver detects and receives the radio frequency signal sent by the digital wireless broadcast signal transmitter and down-converts it to form a baseband signal, and uses the cyclic prefix characteristics of the signal frame and the structural characteristics of the signal frame to perform baseband signal reception processing.

According to the above-mentioned digital wireless broadcast signal transmission method, it is characterized in that: the peak-to-average power ratio of the digital wireless broadcast signal transmitter is reduced by the time-domain discretely coded data sample block from the time-domain discretely coded data sample sub-block through specific 12 kinds of generation modes The signal addition, subtraction, and conjugate operation processing carried out are re-synthesized; the signal frame of the digital wireless broadcast signal transmitter has a periodic time-domain embedded training sequence discrete sample block; the training sequence of the digital wireless broadcast signal transmitter The length X is one of 512, 1024, 2048, the length K of the corresponding FFT data block is 2048, 4096, 8192 respectively, the frequency intervals of the corresponding subcarriers are 4KHz, 2KHz, 1KHz respectively, and the corresponding cyclic prefix The length C is 1/4, 1/8, and 1/16 of the size of the FFT data block length K; the training sequence and service index sequence of the digital wireless broadcast signal transmitter are composed of a series of 1 or -1, which have pseudo-random characteristics ; The training sequence and service index sequence of the digital wireless broadcast signal transmitter are orthogonal to each other; each different service index sequence of the digital wireless broadcast signal transmitter contains and uniquely expresses each system of the digital wireless broadcast signal transmitter Parameters and business mode information; serial concatenated multi-rate punctured convolutional coding is formed by two convolutional codes through random interleaving serial concatenated puncturing, serial concatenated multi-rate punctured convolutional coding The rate is one of 1/4, 4/9, 3/8, 7/16 and 5/9. The digital wireless broadcast signal receiver can make full use of the cyclic prefix characteristics of the signal frame and the structural characteristics of the signal frame to perform baseband signal reception processing, including joint iterative separation processing of the time-frequency domain of the signal frame header and signal frame body.

Features of the present invention:

The present invention is a mixed transmission scheme of time domain and frequency domain. The generation mode of the time-domain discrete coded data sample block with reduced peak-to-average power ratio and the method for selecting the time-domain discrete-coded data sample block with the lowest peak-to-average power ratio of the present invention can not only make full use of the OFDM signal The maximum peak power is very high but the probability of high peak power signal is very low. When the number of subcarriers is large, the real part (or imaginary part) of OFDM signal is a complex Gaussian random process and the amplitude obeys the characteristics of Rayleigh distribution. The generation mode adopted The amount of additional information required to be sent is small, and the original signal of the OFDM signal is easy to process and recover at the receiver, and at the same time, the orthogonality characteristic of the sub-carrier signal will not be destroyed and additional nonlinear distortion will not be generated. The signal frame of the digital wireless broadcast signal transmitter has a periodic time-domain embedded training sequence discrete sample block, the training sequence and service index sequence of the digital wireless broadcast signal transmitter have pseudo-random characteristics, and the training of the digital wireless broadcast signal transmitter Sequences and service index sequences are orthogonal to each other. The time-domain embedded training sequence of the digital wireless broadcast signal transmitter reduces the peak-to-average power ratio and the time-domain discrete-coded data sample block is composed of the time-domain discrete-coded data that reduces the peak-to-average power ratio. It is formed by directly superimposing discrete sample blocks and time-domain embedded training sequence discrete sample blocks, which ensure that the digital radio broadcast signal receiver can achieve fast and accurate frame synchronization, frequency synchronization, time synchronization, channel transmission characteristic estimation, and phase alignment Noise and channel transfer characteristics are reliably tracked. Inserting the cyclic prefix as a guard interval into the time-domain embedding training sequence to reduce the peak-to-average power ratio time-domain discretely coded data sample blocks to form a signal frame can reduce the interference between adjacent signal frames. Channel coding the input data using serial multi-rate punctured convolutional coding provides error correction performance close to the Shannon limit. Each different service index sequence of the digital wireless broadcast signal transmitter contains and uniquely expresses each system parameter and business mode information of the digital wireless broadcast signal transmitter, which can enable the digital TV digital wireless broadcast transmission system to provide free TV broadcast, paid TV broadcasting, confidential information transmission, multimedia value-added services, etc. can control multiple services to meet social needs. The transmission method of the invention has many advantages such as low peak-to-average power ratio, short synchronization time, small clock jitter, anti-channel fading, anti-channel interference, high data rate and controllable multi-service digital TV digital wireless broadcast transmission.

Description of drawings

FIG. 1 is a schematic diagram of an embodiment of signal transmission between a transmitter and a receiver according to a digital radio broadcast signal transmission method of the present invention.

Fig. 2 is a schematic diagram of an embodiment of signal frame formation during signal transmission between a certain transmitter and a receiver according to the digital wireless broadcast signal transmission method of the present invention.

Detailed ways

Specific embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings.

According to the schematic diagram of an embodiment of signal transmission between a certain transmitter and a receiver of the digital wireless broadcasting signal transmission method proposed by the present invention, as shown in Figure 1, proceed according to the following steps:

1) The certain digital wireless broadcast signal transmitter converts the multimedia data stream into a bit stream through a media data processor, and uses the scrambling code sequence generated by the feedback shift register to perform scrambling processing to form an input data bit stream;

2) The certain digital wireless broadcasting signal transmitter forms an FFT encoded data block in the frequency domain by serially cascading multi-rate punctured convolution encoding of its input data bit stream, FFT stands for Fast Discrete Fourier Transform, and FFT encoding The length of the data block is K; the serial concatenated multi-rate punctured convolutional coding is formed by two convolutional codes through random interleaving serial concatenated puncture, and the serial concatenated multi-rate punctured convolutional coding One of the encoding rates 1/4, 4/9, 3/8, 7/16 and 5/9;

3) The certain digital wireless broadcast signal transmitter adopts IFFT to transform the FFT coded data block into a time-domain discrete coded data sample block D _total , and IFFT stands for Inverse Fast Discrete Fourier Transform;

4) The certain digital wireless broadcast signal transmitter divides the time-domain discretely coded data sample block into two blocks in sequence, the time-domain discretely coded data sample sub-block D ₁ and the time-domain discretely coded data sample sub-block D ₂ , D _total = [D ₁ , D ₂ ];

并将降峰均功率比时域离散编码数据样值块

所对应采用的生成模式信息发送给业务指标序列设置单元，其中，D^* ₁表示对时域离散编码数据样值子块D₁的各时域离散编码数据样值进行共轭运算处理而得到的时域离散编码数据样值子块；5) The certain digital wireless broadcast signal transmitter performs signal addition, subtraction, and conjugation on the time-domain discretely encoded data sample sub-block D ₁ and the time-domain discretely encoded data sample sub-block D ₂ through the peak-to-average power ratio adjustment unit Operational processing and re-synthesis of a new time-domain discrete coded data sample block _Dnew , the new time-domain discrete coded data sample block _Dnew is obtained by the following generation mode, generation mode 1 is _Dnew = [D ₁ , D ₂ ] , generating mode 2 as ${\mathrm{D.}}_{\mathrm{new}}=[{\mathrm{D.}}_1,\sqrt{1/2}({\mathrm{D.}}_1+{\mathrm{D.}}_2)],$ Generate schema 3 as ${\mathrm{D.}}_{\mathrm{new}}=[{\mathrm{D.}}_1,\sqrt{1/2}({\mathrm{D.}}_1-{\mathrm{D.}}_2)],$ Generate schema 4 as ${\mathrm{D.}}_{\mathrm{new}}=[\sqrt{1/2}({\mathrm{D.}}_1+{\mathrm{D.}}_2),{\mathrm{D.}}_2],$ Generate schema 5 as ${\mathrm{D.}}_{\mathrm{new}}=[\sqrt{1/2}({\mathrm{D.}}_1-{\mathrm{D.}}_2),{\mathrm{D.}}_2],$ Generate schema 6 as ${\mathrm{D.}}_{\mathrm{new}}=[\sqrt{1/2}({\mathrm{D.}}_1+{\mathrm{D.}}_2),\sqrt{1/2}({\mathrm{D.}}_1-{\mathrm{D.}}_2)],$ Generation mode 7 is D _new = [D ^* ₁ , D ₂ ], generation mode 8 is ${\mathrm{D.}}_{\mathrm{new}}=[{{\mathrm{D.}}^{*}}_1,\sqrt{1/2}({{\mathrm{D.}}^{*}}_1+{\mathrm{D.}}_2)],$ Generate schema 9 as ${\mathrm{D.}}_{\mathrm{new}}=[{{\mathrm{D.}}^{*}}_1,\sqrt{1/2}({{\mathrm{D.}}^{*}}_1-{\mathrm{D.}}_2)],$ Generate schema 10 as ${\mathrm{D.}}_{\mathrm{new}}=[\sqrt{1/2}({{\mathrm{D.}}^{*}}_1+{\mathrm{D.}}_2),{\mathrm{D.}}_2],$ Generate schema 11 as ${\mathrm{D.}}_{\mathrm{new}}=[\sqrt{1/2}({{\mathrm{D.}}^{*}}_1-{\mathrm{D.}}_2),{\mathrm{D.}}_2],$ Generate schema 12 as ${\mathrm{D.}}_{\mathrm{new}}=[\sqrt{1/2}({{\mathrm{D.}}^{*}}_1+{\mathrm{D.}}_2),\sqrt{1/2}({{\mathrm{D.}}^{*}}_1-{\mathrm{D.}}_2)],$ Compare the time-domain discrete-coded data sample block D _new synthesized by 12 generation modes, and select the time-domain discrete-coded data sample block with the lowest peak-to-average power ratio

and reduce the peak-to-average power ratio time-domain discretely coded data sample block

The generated mode information correspondingly adopted is sent to the service index sequence setting unit, wherein, D ^* ₁ means that the time domain discrete coded data samples of the time domain discrete coded data sample sub-block _D1 are conjugated and processed Time-domain discretely coded data sample sub-blocks;

6) The certain digital wireless broadcast signal transmitter uses the training sequence as the real part sequence of the complex training sequence, and uses the service index sequence set by the service index sequence setting unit as the imaginary part sequence of the complex training sequence to form a complex number sequence in the time domain. The discrete sample value blocks of the training sequence, the length of the discrete sample value blocks of the training sequence, service index sequence, and complex training sequence are all X, and the service index sequence contains and uniquely expresses the system parameters and services of the digital wireless broadcast signal transmitter Mode information, X takes one of 512, 1024, 2048;

7) The certain digital wireless broadcast signal transmitter repeats the discrete sample blocks of the complex training sequence formed in the time domain four times continuously in the time domain to form a time domain embedded training sequence discrete sample block, and the time domain embedded training sequence The length of the discrete sample value block is numerically equal to the length of the peak-to-average power ratio time-domain discrete coded data sample block, that is, K=4×X; when X is 512, K is 2048, and the corresponding subcarrier The frequency interval is 4KHz; when X is 1024, K is 4096, and the frequency interval of the corresponding subcarrier is 2KHz; when X is 2048, K is 8192, and the frequency interval of the corresponding subcarrier is 1KHz;

8) The certain digital wireless broadcast signal transmitter directly superimposes the time-domain discrete coded data sample block with reduced peak-to-average power ratio and the discrete sample value block of the time-domain embedded training sequence to form a time-domain embedded training sequence with reduced peak-to-average power ratio in the time domain Discretely coded data sample blocks, as a frame body;

9) The digital wireless broadcast signal transmitter uses the cyclic prefix as a guard interval, that is, inserts the frame header into the time domain embedding training sequence to reduce the peak-to-average power ratio, and the time domain discretely encoded data sample block, that is, the frame body, to form a signal frame, and the cyclic prefix The length is C; when X is 512, C is 1/4 of the size of K; when X is 1024, C is 1/8 of the size of K; when X is 2048, C is 1/16 of the size of K;

10) The certain digital wireless broadcast signal transmitter adopts a square root raised cosine roll-off filter to shape the signal pulse of the signal frame;

11) The certain digital wireless broadcast signal transmitter up-converts the baseband signal to the carrier to form a radio frequency signal and transmits it to the wireless channel in the air;

12) The certain digital wireless broadcast signal receiver detects and receives the radio frequency signal sent by the digital wireless broadcast signal transmitter and down-converts it to form a baseband signal, and uses the cyclic prefix characteristics of the signal frame and the structural characteristics of the signal frame to receive the baseband signal The processing includes joint iterative separation processing of the time-frequency domain of the signal frame header and the signal frame body.

According to the schematic diagram of an embodiment of signal frame formation in the signal transmission process between a transmitter and a receiver of the digital wireless broadcast signal transmission method of the present invention, as shown in Figure 2, the specific implementation is as follows:

The digital wireless broadcast signal transmitter converts the multimedia data stream into a bit stream through a media data processor, and uses the scrambling code sequence generated by the feedback shift register to perform scrambling processing to form an input data bit stream.

The certain digital wireless broadcasting signal transmitter puts its own input data bit stream through serial concatenated multi-code rate punctured convolution coding to form FFT coded data blocks in the frequency domain, and then transforms them into discrete data blocks in the time domain through IFFT. The coded data sample block is generated by the peak-to-average power ratio adjustment unit, and the time-domain discrete coded data sample block with the lowest peak-to-average power ratio is selected, and the corresponding generation mode information is sent to the service index sequence Setting unit; serial concatenated multi-rate punctured convolutional coding is formed by two convolutional codes through random interleaving serial concatenated puncturing, and the coding rate of serial concatenated multi-rate punctured convolutional coding is 1 One of /4, 4/9, 3/8, 7/16 and 5/9.

The FFT data block consists of subcarriers. The length of the FFT data block is K; when X is 512, the corresponding K is 2048, and the frequency interval of the corresponding subcarrier is 4KHz; when X is 1024, the corresponding K is 4096, and the corresponding subcarrier The frequency interval of the frequency is 2KHz; when X is 2048, the corresponding K is 8192, and the frequency interval of the corresponding subcarrier is 1KHz.

The certain digital wireless broadcasting signal transmitter uses the training sequence as the real part sequence of the complex training sequence, uses the service index sequence as the imaginary part sequence of the complex training sequence, forms discrete sample value blocks of the complex training sequence in the time domain, and then In the time domain, it is repeated four times continuously to form discrete sample blocks of the time domain embedding training sequence. The length of the discrete sample block of the training sequence, the service index sequence, and the complex training sequence is X, where X is one of 512, 1024, and 2048, and the length of the discrete sample block of the time domain embedded training sequence is K, K=4× X.

As a digital wireless broadcast signal transmitter, the training sequence and service index sequence are composed of a series of 1 or -1, which have pseudo-random characteristics, and the training sequence and service index sequence are orthogonal to each other. The training sequence satisfying the above characteristics can be realized by a special type of shifted m-sequence as a pseudo-random number sequence and Walsh sequence, Hadamard sequence or orthogonal sequence generated by other methods as an orthogonal sequence. Each different service index sequence contains and uniquely expresses various system parameters and service mode information of the digital radio broadcast signal transmitter.

The certain digital wireless broadcasting signal transmitter directly superimposes the time-domain discrete coded data sample block with reduced peak-to-average power ratio and the discrete sample value block of the time-domain embedded training sequence to form a time-domain embedded training sequence with reduced peak-to-average power ratio time-domain discrete code The data sample block is used as a frame body; a cyclic prefix is inserted into the time domain embedded training sequence peak-to-average power ratio time domain discretely coded data sample block as a guard interval to form a signal frame. The length of the cyclic prefix used as the guard interval is C; when X takes 512, the corresponding C takes 1/4 of the size of K; when X takes 1024, the corresponding C takes 1/8 of the size of K; when X takes When 2048, the corresponding C takes 1/16 of the size of K.

The certain digital radio broadcast signal transmitter employs a square root raised cosine roll-off filter to pulse shape the signal of the signal frame. When X is 512, the roll-off coefficient of the square root raised cosine roll-off filter corresponding to the pulse shaping of the signal frame is 0.1; when X is 1024, the corresponding pulse shaping of the signal frame is The roll-off coefficient of the square root raised cosine roll-off filter is 0.05; when X is 2048, the corresponding roll-off coefficient of the square root raised cosine roll-off filter for pulse shaping the signal frame is 0.025.

The certain digital wireless broadcasting signal transmitter up-converts the baseband signal to the carrier to form a radio frequency signal and transmits it to the wireless channel in the air.

The certain digital wireless broadcast signal receiver detects and receives the radio frequency signal sent by the digital wireless broadcast signal transmitter and converts it down to form a baseband signal, and uses the cyclic prefix characteristics of the signal frame and the structural characteristics of the signal frame to perform baseband signal reception processing, It includes time-frequency domain joint iterative separation processing of signal frame header and signal frame body.

The specific embodiments of the present invention have been described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments, and those skilled in the art can make various modifications without departing from the spirit and scope of the claims of the application modify or remodel.

Claims (8)

1. a digital radio broadcast method for transmitting signals is characterized in that it comprises the following steps:

1) the digital radio broadcast signal transmitter converts the multi-medium data media data processor of flowing through to bit stream, and the scrambler sequence of utilizing feedback shift register to produce is carried out scrambling and handled to form the input data bit flow;

2) the digital radio broadcast signal transmitter is deleted the input data bit of oneself the serially concatenated multi code Rate of Chinese character of flowing through surplus convolutional encoding and is formed the FFT coded data block at frequency domain, and the length of FFT coded data block is K;

3) the digital radio broadcast signal transmitter adopts IFFT that the FFT coded data block is transformed to time domain discrete coded data sample value piece D _Total

4) the digital radio broadcast signal transmitter is divided equally into two with time domain discrete coded data sample value piece in order, the sub-piece D of time domain discrete coded data sample value ₁With the sub-piece D of time domain discrete coded data sample value ₂, D _Total=[D ₁, D ₂];

5) the digital radio broadcast signal transmitter passes through the peak-to-average power ratio adjustment unit to the sub-piece D of time domain discrete coded data sample value ₁, the sub-piece D of time domain discrete coded data sample value ₂Carry out that signal adds, subtracts, the operation independent of conjugation is handled or combinatorial operation is handled and synthetic new time domain discrete coded data sample value piece D again _New, new time domain discrete coded data sample value piece D _NewAdopt following generate pattern to obtain, generate pattern 1 is D _New=[D ₁, D ₂], generate pattern 2 is

Generate pattern 3 is $D_{\mathrm{new}}=[D_1,\sqrt{1/2}(D_1-D_2)],$ Generate pattern 4 is $D_{\mathrm{new}}=[\sqrt{1/2}(D_1+D_2),D_2],$ Generate pattern 5 is

Generate pattern 6 is $D_{\mathrm{new}}=[\sqrt{1/2}(D_1+D_2),\sqrt{1/2}(D_1-D_2)],$ Generate pattern 7 is D _New=[D ^* ₁, D ₂], generate pattern 8 is

Generate pattern 9 is $D_{\mathrm{new}}=[{D^{*}}_1,\sqrt{1/2}({D^{*}}_1-D_2)],$ Generate pattern 10 is $D_{\mathrm{new}}=[\sqrt{1/2}({D^{*}}_1+D_2),D_2],$ Generate pattern 11 is

Generate pattern 12 is $D_{\mathrm{new}}=[\sqrt{1/2}({D^{*}}_1+D_2),\sqrt{1/2}({D^{*}}_1-D_2)],$ Compare the synthetic time domain discrete coded data sample value piece D of 12 kinds of generate patterns _New, choose wherein have a minimum peak-to-average power ratio peak-to-average power ratio time domain discrete coded data sample value piece falls

And peak-to-average power ratio time domain discrete coded data sample value piece will fall

The corresponding generate pattern information that adopts send to the operational indicator sequence unit be set, wherein, D ^* ₁Expression is to the sub-piece D of time domain discrete coded data sample value ₁Each time domain discrete coded data sample value carry out that conjugate operation is handled and the sub-piece of time domain discrete coded data sample value that obtains;

6) the digital radio broadcast signal transmitter with training sequence as the real part sequence of sequence of plural training, the operational indicator sequence is arranged the set operational indicator sequence in unit as the imaginary part sequence of sequence of plural training, constitute the discrete sample block of sequence of plural training in time domain, the length of the discrete sample block of training sequence, operational indicator sequence, sequence of plural training all is X, and the operational indicator sequence is comprising and unique each system parameters and business model information of expressing the digital radio broadcast signal transmitter;

7) discrete sample block of the digital radio broadcast signal transmitter sequence of plural training that will constitute in time domain repeats to form time domains 4 times continuously and embeds training sequence discrete sample block on time domain, time domain embeds the length and the length numerically equal of falling peak-to-average power ratio time domain discrete coded data sample value piece, i.e. K=4 * X of training sequence discrete sample block;

8) the digital radio broadcast signal transmitter will fall peak-to-average power ratio time domain discrete coded data sample value piece, time domain and embed training sequence discrete sample block and directly superpose and form time domain and embed training sequence and fall peak-to-average power ratio time domain discrete coded data sample value piece, as frame;

9) the digital radio broadcast signal transmitter at interval is that frame head inserts time domain and embeds training sequence to fall peak-to-average power ratio time domain discrete coded data sample value piece be frame with Cyclic Prefix as protection, and to form signal frame, the length of Cyclic Prefix is C;

10) the digital radio broadcast signal transmitter adopts square root raised cosine filter that the signal pulse of signal frame is shaped;

11) the digital radio broadcast signal transmitter forms emission of radio frequency signals to the on-air radio channel with the baseband signal up-conversion to carrier wave;

12) the digital radio broadcast signal receiver detect to receive radiofrequency signal that the digital radio broadcast signal transmitter sends and its down-conversion is formed baseband signal, utilizes the architectural characteristic of the Cyclic Prefix characteristic of signal frame and signal frame to carry out baseband signal and receives and handle.

2. by the digital radio broadcast method for transmitting signals of claim 1, it is characterized in that: the length X of the discrete sample block of the training sequence of described digital radio broadcast signal transmitter, operational indicator sequence, sequence of plural training is got in 512,1024,2048.

3. by the digital radio broadcast method for transmitting signals of claim 2, it is characterized in that: described training sequence, operational indicator sequence are formed by a series of 1 or-1, have pseudo-random characteristics.

4. by the digital radio broadcast method for transmitting signals of claim 2, it is characterized in that: described training sequence, operational indicator sequence have orthogonality each other.

5. by the digital radio broadcast method for transmitting signals of claim 1, it is characterized in that: described FFT data block is made up of subcarrier; When X got 512, sub-carrier number got 2048, and the frequency interval of subcarrier is got 4KHz; When X got 1024, sub-carrier number got 4096, and the frequency interval of subcarrier is got 2KHz; When X got 2048, sub-carrier number got 8192, and the frequency interval of subcarrier is got 1KHz.

6. by the digital radio broadcast method for transmitting signals of claim 1, it is characterized in that: the length C value of described Cyclic Prefix is relevant with the X value; When X got 512, C got 1/4 of K size; When X got 1024, C got 1/8 of K size; When X got 2048, C got 1/16 of K size.

7. press the digital radio broadcast method for transmitting signals of claim 1, it is characterized in that: described serially concatenated multi code Rate of Chinese character is deleted surplus convolutional encoding and is deleted surplus forming by two convolutional encodings by the random interleaving serially concatenated, and the encoding rate that the serially concatenated multi code Rate of Chinese character is deleted surplus convolutional encoding is in 1/4,4/9,3/8,7/16 and 5/9.

8. press the digital radio broadcast method for transmitting signals of claim 1, it is characterized in that: the baseband signal that described digital radio broadcast signal receiver carries out receives to be handled, and one of them step is that the time domain and frequency domain combined alternate analysis of signal frame head and signal frame body is handled.

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