CN102291353B - Method for transmitting robust digital radio broadcast signal - Google Patents

Abstract

The invention discloses a robust digital wireless broadcast signal transmission method, which is a mixed transmission scheme of time domain and frequency domain. The robust digital wireless broadcast signal transmission method of the present invention aims at the technical problems that need to be solved due to the signal peak-to-average power ratio, channel time variation, and Doppler frequency shift faced by the wideband multi-carrier digital wireless broadcast transmission system. High-degree reduction of peak-to-average power ratio technology, cascade interleaving coding modulation technology, signal frame time-frequency domain joint iterative separation processing technology, so that the broadband multi-carrier digital wireless broadcasting system has low peak-to-average power ratio, short synchronization time, robustness, and reliability Control multiple services and other advantages.

Description

A robust digital wireless broadcasting signal transmission method

technical field

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

Background technique

At present, television broadcasting has gradually developed from analog to digital. Digital TV broadcasting transmission system, as an important part of digital TV broadcasting, the development of its related technologies is closely related to people's quality of life, and therefore has received extensive attention from people. The technology related to digital TV broadcasting 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 broadcasting, countries are currently focusing on how to provide low-cost, reliable and high-speed mobile solutions for digital TV broadcasting in a complex wave propagation environment. Transmission technology is the key technology of digital TV 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 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.

Under multipath fading channels, the cascade optimization design of coding, interleaving and modulation schemes can achieve the largest possible signal diversity order, so as to obtain independent fading in symbol sequences equal to or exceeding the minimum free distance. Cascading different coding forms can make full use of the advantages of different coding techniques; inserting a bit interleaver between coding and symbol modulation can make the coding and modulation processes relatively independent and expand the diversity order from different multi-ary symbols To a different number of binary bits, so that the order of diversity is significantly improved and has good error characteristics in multipath fading channels.

In the actual communication environment, the performance of the digital TV digital wireless 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 robust digital wireless broadcasting of reliable digital TV.

Using the digital TV digital wireless broadcast transmission system to provide controllable multi-services such as free TV broadcast, paid TV broadcast, confidential information transmission, and multimedia value-added services is the embodiment of the new generation of digital TV robust digital wireless broadcast transmission system to meet social needs.

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

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.183-194, .2006.

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.

G.Caire, G.Taricco, E.Biglieri, "Bit-interleaved coded modulation," IEEE Trans.Information Theory, vol.44, no.3, pp.927-946, May 1998.

S. Benedetto, D. Divsalar, G. Montorsi, and F. Pollara, "Serial concatenation of interleaved codes: performance analysis s, design, and iterative decoding," IEEE Trans. Inform. Theory, vol.44, no.3, pp. 909-925, May 1998.

Contents of the invention

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

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

1) The robust 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 robust digital wireless broadcast signal transmitter passes its input data bit stream through BCH encoding (BoseChaudhuri Hocquenghem, BCH), bit interleaving, multi-bit rate punctured convolutional coding, symbol modulation, and symbol interleaving in the frequency domain Form FFT cascaded interleaved coded modulation data block, FFT means fast discrete Fourier transform, and the length of FFT cascaded interleaved coded modulated data block is K;

3) The robust digital wireless broadcast signal transmitter uses IFFT to transform the FFT concatenated interleaved coded modulation data block into a time-domain discrete concatenated interleaved coded modulated data sample block D _total , and IFFT means inverse fast discrete Fourier transform;

4) The robust digital wireless broadcasting signal transmitter divides the time-domain discrete concatenated interleaved coded modulation data sample block into two equally in sequence, the time-domain discrete concatenated interleaved coded modulated data sample sub-block D ₁ and the time-domain discrete level Interleaved coded modulation data sample sub-block D ₂ , D _total = [D ₁ , D ₂ ];

并将降峰均功率比时域离散级联交织编码调制数据样值块

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表示对时域离散级联交织编码调制数据样值子块D₁的各时域离散级联交织编码调制数据样值进行共轭运算处理而得到的时域离散级联交织编码调制数据样值子块；5) The robust digital wireless broadcast signal transmitter uses the peak-to-average power ratio adjustment unit to perform the time-domain discrete concatenated interleaving coded modulation data sample sub-block D ₁ and the time-domain discrete concatenated interleaved coded modulated data sample sub-block D ₂ Signal addition, subtraction, and conjugate operation processing and re-synthesis of a new time-domain discrete concatenated interleaved coded modulation data sample block _Dnew , the new time-domain discrete concatenated interleaved coded modulated data sample block _Dnew is obtained by the following generation mode , generation mode 1 is D _new = [D ₁ , D ₂ ], generation mode 2 is ${\mathrm{D.}}_{\mathrm{new}}=[{\mathrm{D.}}_1,\sqrt{1/2}({\mathrm{D.}}_1+{\mathrm{D.}}_2)],$ 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 concatenated interleaved coded modulation data sample block _Dnew synthesized by 12 generation modes, and select the time-domain discrete concatenated interleaved coded modulated data sample block with the lowest peak-to-average power ratio among them

And reduce the peak-to-average power ratio time-domain discrete concatenated interleaved coding modulation data sample block

The corresponding generation mode information adopted is sent to the service index sequence setting unit, wherein, D ^* ₁ represents each time-domain discrete concatenated interleaving coded modulation data sample value for the time domain discrete concatenated interleaved coded modulation data sample sub-block D ₁ Time-domain discrete concatenated interleaved coded modulation data sample sub-block obtained by performing conjugate operation processing;

6) The robust 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 training sequence in the time domain. The discrete sample value blocks of the sequence, the length of the discrete sample value blocks of the training sequence, the service index sequence, and the complex training sequence are all X, and the service index sequence contains and uniquely expresses the system parameters of the robust digital wireless broadcasting signal transmitter and business model information;

7) The robust digital wireless broadcast signal transmitter repeats the discrete sample blocks of the complex training sequence formed in the time domain 4 times continuously in the time domain to form a time domain embedded training sequence discrete sample block, and the time domain embedded training sequence is discrete The length of the sample value block and the length of the peak-to-average power ratio time-domain discrete concatenated interleaved coded modulation data sample block are equal in value, that is, K=4×X;

8) The robust digital wireless broadcasting signal transmitter directly superimposes the reduced peak-to-average power ratio time-domain discrete cascaded interleaved coded modulation data sample blocks and the time-domain embedded training sequence discrete sample blocks to form a time-domain embedded training sequence with reduced peak-to-average power Than the time-domain discrete cascaded interleaved coding modulated data sample block, as a frame body;

9) The robust 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 time-domain discrete cascade interleaving codes the modulated data sample block, that is, the frame body, to form a signal frame , the length of the cyclic prefix is C;

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

12) The robust digital wireless broadcast signal receiver detects and receives the radio frequency signal sent by the robust 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 Receive processing.

According to the above-mentioned robust digital wireless broadcasting signal transmission method, it is characterized in that: the peak-to-average power ratio of the robust digital wireless broadcasting signal transmitter is reduced by time-domain discrete concatenated interleaved coded modulation data sample block by time-domain discrete concatenated interleaved coded Modulated data sample sub-blocks are re-synthesized through signal addition, subtraction, and conjugate operation processing for 12 specific generation modes; the signal frame of the robust digital wireless broadcast signal transmitter has a periodic time-domain embedded training sequence discrete Sample block; the length X of the training sequence of the robust digital wireless broadcast signal transmitter is one of 512, 1024, and 2048, and the length K of the corresponding FFT concatenated interleaved coded modulation data block is 2048, 4096, 8192, respectively, The frequency intervals of the corresponding subcarriers are 4KHz, 2KHz, and 1KHz respectively, and the corresponding cyclic prefix lengths C are 1/4, 1/8, and 1/16 of the length K of the FFT concatenated interleaving coded modulation data block; The training sequence and service index sequence of the stick 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 robust digital wireless broadcast signal transmitter are orthogonal to each other The various service index sequences of the robust digital wireless broadcast signal transmitter contain and uniquely express the system parameters and service mode information of the robust digital wireless broadcast signal transmitter; the coding of multi-bit rate punctured convolutional coding The rate is one of 1/4, 1/2, 5/8, 3/4, and 7/8; the bit interleaving adopts random interleaving; the symbol modulation is one of QPSK, 16QAM, 32QAM, and 64QAM, and the symbol Constellation map mapping adopts Gray code mapping; symbol interleaving adopts random interleaving. The robust 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 the 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 peak-to-average power ratio time-domain discrete concatenated interleaved coded modulation data sample block and the method for selecting the peak-to-average power ratio time-domain discrete cascaded interleaved coded modulated data sample block with the lowest peak-to-average power ratio of the present invention , not only can make full use of the maximum peak power of OFDM signal 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 Rayleigh distribution The characteristics of the used generation mode require a small amount of additional information to be sent, and it is easy to process and restore the original signal of the OFDM signal at the receiver without destroying the orthogonality of the subcarrier signal and generating additional nonlinearity distortion. The signal frame of the robust digital wireless broadcast signal transmitter has periodic time-domain embedded training sequence discrete sample blocks, the training sequence and service index sequence of the robust digital wireless broadcast signal transmitter have pseudo-random characteristics, and the robust digital wireless broadcast signal transmitter has pseudo-random characteristics. The training sequence and service index sequence of the broadcast signal transmitter are orthogonal to each other, and the time-domain embedding training sequence of the robust digital wireless broadcast signal transmitter reduces the peak-to-average power ratio to the time-domain discrete cascade interleaving coded modulation data sample block It is formed by the direct superposition of the time-domain discrete cascaded interleaving coded modulation data sample blocks and the time-domain embedded training sequence discrete sample blocks, which ensure that the robust digital wireless broadcast signal receiver can achieve fast and accurate frame synchronization, frequency synchronization, time synchronization, estimation of channel transmission characteristics, and reliable tracking of phase noise and channel transmission characteristics. 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 discrete concatenated interleaving coding modulated data sample blocks to form a signal frame, which can reduce the interference between adjacent signal frames. The cascaded interleaving coding and modulation of the input data increases the diversity order, which makes the communication system have good bit error characteristics in the multipath fading channel. The various service index sequences of the robust digital wireless broadcast signal transmitter contain and uniquely express the system parameters and business mode information of the robust digital wireless broadcast signal transmitter, which can make the digital TV robust digital wireless broadcast transmission system capable of Provide controllable multi-services such as free TV broadcasting, paid TV broadcasting, confidential information transmission, and multimedia value-added services to meet social needs. The transmission method of the present invention has low peak-to-average power ratio, short synchronization time, small clock jitter, anti-channel fading, anti-channel interference, can provide high-level interleaving code modulation data rate controllable multi-service digital TV robust digital wireless broadcast transmission, etc. Many advantages.

Description of drawings

Fig. 1 is a schematic diagram of an embodiment of signal transmission between a certain transmitter and a receiver according to the robust digital wireless broadcasting signal transmission method of the present invention.

Fig. 2 is a schematic diagram of an embodiment of signal frame formation during the signal transmission process between a transmitter and a receiver according to the robust digital wireless broadcasting 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 the signal transmission between a certain transmitter and the receiver of the robust digital wireless broadcasting signal transmission method proposed by the present invention, as shown in Figure 1, the following steps are carried out:

1) The certain robust 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 robust digital wireless broadcast signal transmitter forms FFT in the frequency domain after BCH encoding, bit interleaving, multi-rate punctured convolutional coding, symbol modulation, and symbol interleaving of its input data bit stream Concatenated interleaved coding modulation data block, FFT means fast discrete Fourier transform, the length of FFT concatenated interleaving coding modulation data block is K; the coding rate of multi-code rate punctured convolutional coding is 1/4, 1/2, 5/ One of 8, 3/4, and 7/8; bit interleaving adopts random interleaving; symbol modulation is one of QPSK, 16QAM, 32QAM, and 64QAM; symbol constellation mapping uses Gray code mapping; symbol interleaving Using random interleaving.

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

4) The certain robust digital wireless broadcasting signal transmitter divides the time-domain discrete concatenated interleaved coded modulation data sample block into two equally in sequence, the time domain discrete concatenated interleaved coded modulated data sample sub-block _D1 and the time domain Domain discrete concatenated interleaving coding modulated data sample sub-block D ₂ , D _total = [D ₁ , D ₂ ];

并将降峰均功率比时域离散级联交织编码调制数据样值块

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表示对时域离散级联交织编码调制数据样值子块D₁的各时域离散级联交织编码调制数据样值进行共轭运算处理而得到的时域离散级联交织编码调制数据样值子块；5) The certain robust digital wireless broadcast signal transmitter uses the peak-to-average power ratio adjustment unit to adjust the time-domain discrete concatenated interleaved coded modulation data sample sub-block D ₁ , the time-domain discrete concatenated interleaved coded modulated data sample sub-block D ₂ performs signal addition, subtraction, and conjugate operation processing and re-synthesizes a new time-domain discrete concatenated interleaved coded modulation data sample block _Dnew , and the new time-domain discrete concatenated interleaved coded modulated data sample block _Dnew is as follows The generation mode is obtained, the generation mode 1 is D _new = [D ₁ , D ₂ ], and the generation mode 2 is ${\mathrm{D.}}_{\mathrm{new}}=[{\mathrm{D.}}_1,\sqrt{1/2}({\mathrm{D.}}_1+{\mathrm{D.}}_2)],$ 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 concatenated interleaved coded modulation data sample block _Dnew synthesized by 12 generation modes, and select the time-domain discrete concatenated interleaved coded modulated data sample block with the lowest peak-to-average power ratio among them

And reduce the peak-to-average power ratio time-domain discrete concatenated interleaved coding modulation data sample block

The corresponding generation mode information adopted is sent to the service index sequence setting unit, wherein, D ^* ₁ represents each time-domain discrete concatenated interleaving coded modulation data sample value for the time domain discrete concatenated interleaved coded modulation data sample sub-block D ₁ Time-domain discrete concatenated interleaved coded modulation data sample sub-block obtained by performing conjugate operation processing;

6) The certain robust 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, in the time domain The discrete sample blocks that constitute the complex training sequence, the length of the training sequence, the service index sequence, and the discrete sample block of the complex training sequence are all X, and the service index sequence contains and uniquely expresses each of the robust digital wireless broadcast signal transmitters. System parameters and business mode information, X takes one of 512, 1024, and 2048;

7) The certain robust digital wireless broadcasting signal transmitter repeats the discrete sample blocks of the complex training sequence formed in the time domain continuously 4 times in the time domain to form a time domain embedded training sequence discrete sample block, and the time domain embedding The length of the training sequence discrete sample block is equal to the length of the peak-to-average power ratio time-domain discrete concatenated interleaved coded modulation data sample block, that is, K=4×X; when X is 512, K is 2048, The frequency interval of the corresponding subcarrier 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 Take 1KHz;

8) The certain robust digital wireless broadcasting signal transmitter directly superimposes the peak-to-average power ratio time-domain discrete concatenated interleaved coded modulation data sample block and the time-domain embedded training sequence discrete sample block to form a time-domain embedded training sequence drop Peak-to-average power ratio time-domain discrete cascaded interleaved coded modulation data sample block, as a frame body;

9) The certain robust digital wireless broadcasting signal transmitter uses the cyclic prefix as the guard interval, that is, the frame header is inserted into the time domain embedding training sequence to reduce the peak-to-average power ratio, and the time domain discrete cascaded interleaved coded modulation data sample block is the frame body, so that Form a signal frame, the length of the cyclic prefix 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 K 1/16 of the size;

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

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

The certain robust 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 robust digital wireless broadcasting signal transmitter forms FFT concatenation in the frequency domain after BCH coding, bit interleaving, multi-rate punctured convolutional coding, symbol modulation, and symbol interleaving of its input data bit stream The interleaved coded modulation data block is transformed into a discrete concatenated interleaved coded modulated data sample block in the time domain by IFFT, and the peak-to-average power ratio reduction time with the lowest peak-to-average power ratio is selected through the peak-to-average power ratio adjustment unit. At the same time, the domain discrete cascaded interleaved coded modulation data sample block sends the corresponding generating mode information to the service index sequence setting unit. The coding rate of multi-code rate punctured convolutional coding is one of 1/4, 1/2, 5/8, 3/4 and 7/8; the bit interleaving adopts random interleaving; the symbol modulation is QPSK, 16QAM, One of 32QAM and 64QAM, the symbol constellation mapping method adopts Gray code mapping; the symbol interleaving adopts random interleaving method.

The FFT cascaded interleaved coded modulation data block consists of subcarriers. The length of the FFT concatenated interleaving coded modulation 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, The frequency interval of the corresponding subcarriers is 2KHz; when X is 2048, the corresponding K is 8192, and the frequency interval of the corresponding subcarriers is 1KHz.

The certain robust 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 as the imaginary part sequence of the complex training sequence to form discrete sample value blocks of the complex training sequence in the time domain, Repeat it four times continuously in the time domain to form discrete sample blocks of 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 robust 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 robust digital radio broadcast signal transmitter.

The certain robust digital wireless broadcasting signal transmitter directly superimposes the peak-to-average power ratio time-domain discrete concatenated interleaved coded modulation data sample block and the time-domain embedded training sequence discrete sample block to form a time-domain embedded training sequence peak-to-average reduction Power ratio time-domain discrete concatenated interleaved coded modulation data sample block, as a frame body; in the time domain embedding training sequence peak-to-average power ratio time domain discrete concatenated interleaved coded modulated data sample block, insert a cyclic prefix as a guard interval, 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 robust 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 robust digital wireless broadcast signal transmitter converts the baseband signal up to the carrier to form a radio frequency signal and transmits it to the air wireless channel.

The certain robust digital wireless broadcast signal receiver detects and receives the radio frequency signal sent by the robust digital wireless broadcast signal transmitter and converts it down to form a baseband signal. Signal receiving processing, which 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 robust digital radio broadcast method for transmitting signals is characterized in that it comprises the following steps:

1) robust 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) robust digital radio broadcast signal transmitter is flowed through the input data bit of oneself and is formed the cascade interweaved coding modulation data piece of FFT at frequency domain after Bose-Chaudhuri-Hocquenghem Code, Bit Interleave, multi code Rate of Chinese character are deleted surplus convolutional encoding, code element modulation, symbol interleave, BCH represents Bose Chaudhuri Hocquenghem, and the length of the cascade interweaved coding modulation data piece of FFT is K;

3) robust digital radio broadcast signal transmitter adopts IFFT that the cascade interweaved coding modulation data piece of FFT is transformed to the cascade interweaved coding modulation data sample value of time domain discrete piece D _Total

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

5) robust digital radio broadcast signal transmitter passes through the peak-to-average power ratio adjustment unit to the sub-piece D of the cascade interweaved coding modulation data sample value of time domain discrete ₁, the sub-piece D of the cascade interweaved coding modulation data sample value of time domain discrete ₂Carry out that signal adds, subtracts, conjugate operation is handled and the synthetic new cascade interweaved coding modulation data sample value of time domain discrete piece D again _New, the cascade interweaved coding modulation data sample value of new time domain discrete 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=pD ^* ₁, D ₂], generate pattern 8 is $D_{\mathrm{new}}=[{D^{*}}_1,\sqrt{1/2}({D^{*}}_1+D_2)],$ Generate pattern 9 is $D_{\mathrm{new}}=[{D^{*}}_1,\sqrt{1/2}({D^{*}}_1-D_2)],$ Generate pattern 10 is

Generate pattern 11 is $D_{\mathrm{new}}=[\sqrt{1/2}({D^{*}}_1-D_2),D_2],$ Generate pattern 12 is $D_{\mathrm{new}}=[\sqrt{1/2}({D^{*}}_1+D_2),\sqrt{1/2}({D^{*}}_1-D_2)],$ Compare the synthetic cascade interweaved coding modulation data sample value of the time domain discrete piece D of 12 kinds of generate patterns _New, choose wherein have a minimum peak-to-average power ratio the cascade interweaved coding modulation data sample value of peak-to-average power ratio time domain discrete piece falls

And the cascade interweaved coding modulation data sample value of peak-to-average power ratio time domain discrete 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 the cascade interweaved coding modulation data sample value of time domain discrete ₁The cascade interweaved coding modulation data sample value of each time domain discrete carry out that conjugate operation is handled and the sub-piece of the cascade interweaved coding modulation data sample value of time domain discrete that obtains;

6) robust 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 robust digital radio broadcast signal transmitter;

7) discrete sample block of the robust 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 the cascade interweaved coding modulation data sample value of peak-to-average power ratio time domain discrete piece, i.e. K=4 * X of training sequence discrete sample block;

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

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

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

11) robust 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) robust digital radio broadcast signal receiver detect to receive radiofrequency signal that robust 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 robust 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 robust digital radio broadcast signal transmitter, operational indicator sequence, sequence of plural training is got in 512,1024,2048.

3. by the robust 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 robust 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 robust digital radio broadcast method for transmitting signals of claim 1, it is characterized in that: the cascade interweaved coding modulation data piece of described FFT 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 robust 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. by the robust digital radio broadcast method for transmitting signals of claim 1, it is characterized in that: the encoding rate that described multi code Rate of Chinese character is deleted surplus convolutional encoding is in 1/4,1/2,5/8,3/4 and 7/8; Bit Interleave adopts the random interleaving mode; Code element is modulated to a kind of among QPSK, 16QAM, 32QAM and the 64QAM, and symbol constellations figure mapping mode adopts the Gray code mapping; Symbol interleave adopts the random interleaving mode.

8. press the robust digital radio broadcast method for transmitting signals of claim 1, it is characterized in that: the baseband signal that described robust 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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