CN102281244B - Anti-interference wireless digital broadcast signal transmission method for single frequency network - Google Patents

Abstract

The invention discloses an anti-interference wireless digital broadcast signal transmission method for a single frequency network, and belongs to a time domain, frequency domain and space domain mixed transmission scheme. The anti-interference wireless digital broadcast signal transmission method for the single frequency network has the advantages of low peak-to-average power ratio, short synchronous time, channel interference resistance, controllable multi-service and the like.

Description

A single frequency network anti-jamming wireless digital broadcasting signal transmission method

technical field

The invention belongs to the field of wireless communication, and more specifically relates to a single frequency network anti-jamming wireless digital broadcasting signal transmission method.

Background technique

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 wireless digital 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. Therefore, it is necessary to consider how to reduce the occurrence probability of large peak power signals in OFDM signals and reduce nonlinearity. Solutions for distortion effects. BICM technology (Bit Interleaved Coded Modulation, BICM) uses a bit interleaver and makes the coding and modulation processes relatively independent, and the diversity order is significantly improved, so that the communication system has good error characteristics in multipath fading channels . Adopting the networking mode of the single frequency network can greatly improve the frequency spectrum utilization rate of the digital TV wireless digital broadcasting transmission system. In the actual single frequency network communication environment, the performance of the digital TV wireless digital broadcasting communication system is affected by factors such as synchronization time, clock jitter, channel fading, and channel interference. The single frequency network anti-jamming wireless digital broadcast signal transmitter transmission method is the key technology for realizing the reliable digital TV single frequency network anti-jamming wireless digital broadcasting. Using the digital TV single frequency network anti-interference wireless digital broadcasting transmission system to provide controllable multi-services such as free TV broadcasting, paid TV broadcasting, confidential information transmission, multimedia value-added services, etc. is the embodiment of the new generation of digital TV wireless digital broadcasting transmission system to meet social needs.

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

Contents of the invention

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

A kind of single frequency network anti-jamming wireless digital broadcasting signal transmission method proposed by the present invention is characterized in that it comprises the following steps:

1) The central data manager of the single frequency network 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 network data manager of the single frequency network forms an FFT bit interleaved coded modulation data block in the frequency domain through multi-code rate punctured convolution coding, bit interleaving, and symbol modulation of the input data bit stream, and FFT stands for Fast Discrete Fourier Transform , the length of the FFT bit-interleaved coded modulation data block is K;

3) The network data manager of the single frequency network uses a space frequency coder with a code rate of 1 to modulate the FFT bit interleaved coded modulation data block formed in the frequency domain to each anti-jamming wireless digital broadcasting signal transmitter in the single frequency network Form space-frequency modulation FFT bit-interleaved coding modulation data block on the branch, and adjust the time synchronization of each anti-jamming wireless digital broadcast signal transmitter branch to ensure that all transmitters in the network perform space-frequency modulation FFT bit-interleaving coding at the same time Modulate data blocks for processing;

4) Each anti-jamming wireless digital broadcasting signal transmitter in the single frequency network uses IFFT to transform the space-frequency modulation FFT bit-interleaved coded modulation data block into a space-frequency modulated time-domain discrete bit-interleaved coded modulated data sample block D _total , IFFT represents Inverse Fast Discrete Fourier Transform;

5) Each anti-jamming wireless digital broadcasting signal transmitter in the single frequency network divides the space-frequency modulation time-domain discrete bit interleaving coding modulation data sample block into two equally in sequence, and the space-frequency modulation time domain discrete bit interleaving coding modulation data sample Value sub-block D ₁ and space-frequency modulation time-domain discrete bit interleaving coded modulation data sample sub-block D ₂ , D _total = [D ₁ , D ₂ ];

并将降峰均功率比空频调制时域离散比特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表示对空频调制时域离散比特交织编码调制数据样值子块D₁的各空频调制时域离散比特交织编码调制数据样值进行共轭运算处理而得到的空频调制时域离散比特交织编码调制数据样值子块；6) Each anti-jamming wireless digital broadcasting signal transmitter in the single frequency network uses the peak-to-average power ratio adjustment unit to encode and modulate the data sample sub-block D ₁ in the space-frequency modulation time-domain discrete bit interleaving, space-frequency modulation time-domain discrete bit interleaving Coded and modulated data sample sub-block D ₂ performs signal addition, subtraction, and conjugate operation processing and recombines a new space-frequency modulation time-domain discrete bit interleaving coded modulation data sample block _Dnew , a new space-frequency modulation time-domain discrete bit The interleaved coded modulation data sample block D _new is obtained by the following generation mode, 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 space-frequency modulation time-domain discrete bit interleaving coded modulation data sample block D _new synthesized by 12 kinds of generation modes, and select the space-frequency modulation time domain discrete bit interleaved coded modulation data sample with the lowest peak-to-average power ratio. value block

And reduce the peak-to-average power ratio space-frequency modulation time-domain discrete bit interleaving coding modulation data sample block

The generation mode information adopted correspondingly is sent to the service index sequence setting unit, wherein, D ^* ₁ represents each space-frequency modulation time-domain discrete bit interleaving coding of the space-frequency modulation time-domain discrete bit interleaving coding modulation data sample sub-block D ₁ Space-frequency modulated time-domain discrete bit interleaved coded modulated data sample sub-block obtained by performing conjugate operation processing on modulated data samples;

7) Each anti-interference wireless digital broadcast signal transmitter in the single frequency network uses the training sequence as the real part sequence of the complex training sequence, and the service index sequence set by the service index sequence setting unit as the imaginary part sequence of the complex training sequence, in 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 resistance in the single frequency network. Interfering with various system parameters and business mode information of wireless digital broadcasting signal transmitters;

8) Each anti-interference wireless digital broadcast signal transmitter in the single frequency network repeats the discrete sample value block of the complex training sequence formed on the time domain continuously for 4 times in the time domain to form the time domain embedded training sequence discrete sample value block, The length of the time-domain embedding training sequence discrete sample block is equal to the length of the peak-to-average power ratio space-frequency modulation time-domain discrete bit interleaving coded modulation data sample block, that is, K=4×X;

9) Each anti-interference wireless digital broadcasting signal transmitter in the single frequency network directly superimposes the peak-to-average power ratio, space-frequency modulation, time-domain discrete bit interleaving coded modulation data sample block, and time-domain embedded training sequence discrete sample block to form Domain embedding training sequence to reduce peak-to-average power ratio space-frequency modulation time-domain discrete bit interleaving coded modulation data sample block, as a frame body;

10) Each anti-interference wireless digital broadcasting signal transmitter in the single frequency network uses the cyclic prefix as a guard interval, that is, the frame header is inserted into the training sequence in the time domain, and the peak-to-average power ratio is reduced. That is, the frame body to form a signal frame, and the length of the cyclic prefix is C;

11) Each anti-jamming wireless digital broadcasting signal transmitter in the single frequency network uses a square root raised cosine roll-off filter to shape the signal pulse of the signal frame;

12) Each anti-interference wireless digital broadcast signal transmitter in the single frequency network up-converts the baseband signal to the carrier to form a radio frequency signal and transmit it to the wireless channel in the air;

13) The anti-jamming wireless digital broadcasting signal receiver in the single frequency network detects and receives the radio frequency signal sent by each anti-jamming wireless digital broadcasting signal transmitter in the single frequency network and down-converts it to form a baseband signal, and utilizes the cycle of the signal frame Prefix characteristics and structural characteristics of the signal frame are used for baseband signal reception processing.

According to the above-mentioned single frequency network anti-interference wireless digital broadcast signal transmission method, it is characterized in that: the peak-to-average power ratio of each anti-interference wireless digital broadcast signal transmitter in the single frequency network The sample block is re-synthesized by the space-frequency modulation time-domain discrete bit interleaving coding modulation data sample sub-block through the signal addition, subtraction, and conjugate operation processing of 12 specific generation modes; each anti-jamming wireless network in the single frequency network The signal frame of the digital broadcast signal transmitter has a periodic time-domain embedded training sequence discrete sample block; the length X of the training sequence of each anti-jamming wireless digital broadcast signal transmitter in the single frequency network is 512, 1024, 2048 The length K of the corresponding space-frequency modulation FFT bit-interleaved coding modulation data block is 2048, 4096, 8192 respectively, the frequency interval of the corresponding subcarrier is 4KHz, 2KHz, 1KHz respectively, and the corresponding cyclic prefix length C They are respectively 1/4, 1/8, and 1/16 of the length K of space-frequency modulation FFT bit-interleaved coding modulation data block; the training sequence and service index sequence of each anti-jamming wireless digital broadcasting signal transmitter in the single frequency network are composed of A series of 1 or -1, with pseudo-random characteristics; each anti-jamming wireless digital broadcasting signal transmitter training sequence and service index sequence in the single frequency network are orthogonal to each other; each anti-jamming Each different service index sequence of the interference wireless digital broadcast signal transmitter contains and uniquely expresses each system parameter and business mode information of each anti-interference wireless digital broadcast signal transmitter in the single frequency network; the code rate of the space frequency coder It is 1; the coding rate of multi-code-rate punctured convolutional coding for the input data is one of 1/4, 1/2, 5/8, 3/4 and 7/8; the bit interleaving adopts random interleaving; the code The element modulation is one of QPSK, 16QAM, 32QAM and 64QAM, and the symbol constellation map mapping method adopts Gray code mapping. The anti-interference wireless digital broadcasting signal receiver in the single frequency network 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 the time-frequency domain joint iteration of the signal frame header and signal frame body Separate processing.

Features of the present invention:

The present invention is a mixed transmission scheme of time domain, frequency domain and space domain. Generation mode of the reduced peak-to-average power ratio space-frequency modulation time-domain discrete bit interleaving coded modulation data sample block and the reduced peak-to-average power ratio space-frequency modulation time-domain discrete bit interleaved coded modulated data sample with the lowest peak-to-average power ratio of the present invention The value block selection method can not only make full use of the high peak power of the OFDM signal, but the probability of the high peak power signal is very low. When the number of subcarriers is large, the real part (or imaginary part) of the OFDM signal is a complex Gaussian random process and The amplitude obeys the characteristics of Rayleigh distribution, the amount of additional information required for the adopted generation mode is small, and it is easy to process and restore the original signal of the OFDM signal at the receiver, and at the same time it will not destroy the orthogonality characteristics of the subcarrier signal and will not produce Additional nonlinear distortion. In the signal frame of each anti-jamming wireless digital broadcasting signal transmitter in the single frequency network, there are periodic time domain embedded training sequence discrete sample blocks, and the training sequence of each anti-jamming wireless digital broadcasting signal transmitter in the single frequency network, The service index sequence has pseudo-random characteristics. The training sequence and service index sequence of each anti-interference wireless digital broadcasting signal transmitter in the single frequency network are orthogonal to each other. Each anti-jamming wireless digital broadcasting signal transmission in the single frequency network The time-domain embedding training sequence of the machine is reduced peak-to-average power ratio space frequency It is formed by direct superposition of discrete sample blocks embedded in the training sequence, which ensures that each wireless digital broadcast signal receiver in the single frequency network 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 training sequence in the time domain to reduce the peak-to-average power ratio, space-frequency modulation, time-domain discrete bit interleaving, coded and modulated data sample blocks to form a signal frame, which can reduce the interference between adjacent signal frames. Using BICM to perform bit-interleaved coding and modulation on the input data improves the diversity order and makes the communication system have good bit error characteristics in multi-path fading channels. Each different service index sequence of each anti-jamming wireless digital broadcasting signal transmitter in the single frequency network contains and uniquely expresses each system parameter and business mode information of each anti-jamming wireless digital broadcasting signal transmitter in the single frequency network, It can make the anti-jamming wireless digital broadcast transmission system of the digital TV single frequency network to provide controllable multi-services such as free TV broadcast, paid TV broadcast, confidential information transmission, and multimedia value-added services to meet social needs. The transmission method of the present 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 controllable multi-service digital television single frequency network anti-jamming wireless digital broadcast transmission, etc. advantage.

Description of drawings

FIG. 1 is a schematic diagram of an embodiment of signal transmission between a transmitter and a receiver of a single frequency network anti-jamming wireless digital broadcasting signal transmission method according to the present invention.

Fig. 2 is a schematic diagram of an embodiment of signal frame formation during the signal transmission process between the transmitter and the receiver of the single frequency network anti-jamming wireless digital 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 embodiment of the signal transmission between the transmitter and the receiver of the single frequency network anti-jamming wireless digital broadcast signal transmission method proposed by the present invention (assuming that there are N transmitters in the single frequency network), as shown in Figure 1, follow the steps conduct:

1) The central data manager of the single frequency network 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 network data manager of the single frequency network forms an FFT bit interleaved coded modulation data block in the frequency domain through multi-code rate punctured convolution coding, bit interleaving, and symbol modulation of the input data bit stream, and FFT stands for Fast Discrete Fourier Transform , the length of the FFT bit-interleaved coding modulation data block is K; the coding rate of the multi-code rate punctured convolutional coding is one of 1/4, 1/2, 5/8, 3/4 and 7/8, and the bit interleaving Random interleaving is adopted, the symbol modulation is one of QPSK, 16QAM, 32QAM and 64QAM, and the symbol constellation mapping method adopts Gray code mapping;

3) The network data manager of the single frequency network uses a space frequency coder with a code rate of 1 to modulate the FFT bit interleaved coded modulation data block formed in the frequency domain to each anti-jamming wireless digital broadcasting signal transmitter in the single frequency network Form space-frequency modulation FFT bit-interleaved coding modulation data block on the branch, and adjust the time synchronization of each anti-jamming wireless digital broadcast signal transmitter branch to ensure that all transmitters in the network perform space-frequency modulation FFT bit-interleaving coding at the same time Modulate data blocks for processing;

4) Each anti-jamming wireless digital broadcasting signal transmitter in the single frequency network uses IFFT to transform the space-frequency modulation FFT bit-interleaved coded modulation data block into a space-frequency modulated time-domain discrete bit-interleaved coded modulated data sample block D _total , IFFT represents Inverse Fast Discrete Fourier Transform;

5) Each anti-jamming wireless digital broadcasting signal transmitter in the single frequency network divides the space-frequency modulation time-domain discrete bit interleaving coding modulation data sample block into two equally in sequence, and the space-frequency modulation time domain discrete bit interleaving coding modulation data sample Value sub-block D ₁ and space-frequency modulation time-domain discrete bit interleaving coded modulation data sample sub-block D ₂ , D _total = [D ₁ , D ₂ ];

并将降峰均功率比空频调制时域离散比特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表示对空频调制时域离散比特交织编码调制数据样值子块D₁的各空频调制时域离散比特交织编码调制数据样值进行共轭运算处理而得到的空频调制时域离散比特交织编码调制数据样值子块；6) Each anti-jamming wireless digital broadcasting signal transmitter in the single frequency network uses the peak-to-average power ratio adjustment unit to encode and modulate the data sample sub-block D ₁ in the space-frequency modulation time-domain discrete bit interleaving, space-frequency modulation time-domain discrete bit interleaving Coded and modulated data sample sub-block D ₂ performs signal addition, subtraction, and conjugate operation processing and recombines a new space-frequency modulation time-domain discrete bit interleaving coded modulation data sample block _Dnew , a new space-frequency modulation time-domain discrete bit The interleaved coded modulation data sample block D _new is obtained by the following generation mode, 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 space-frequency modulation time-domain discrete bit interleaving coding modulation data sample block D _new synthesized by 12 kinds of generation modes, and select the space-frequency modulation time domain discrete bit interleaving coding modulation data sample with the lowest peak-to-average power ratio. value block

And reduce the peak-to-average power ratio space-frequency modulation time-domain discrete bit interleaving coded modulation data sample block

The generation mode information adopted correspondingly is sent to the service index sequence setting unit, wherein, D ^* ₁ represents each space-frequency modulation time-domain discrete bit interleaving coding of the space-frequency modulation time-domain discrete bit interleaving coding modulation data sample sub-block D ₁ Space-frequency modulated time-domain discrete bit interleaving coded modulated data sample sub-block obtained by performing conjugate operation processing on modulated data samples;

7) Each anti-interference wireless digital broadcast signal transmitter in the single frequency network uses the training sequence as the real part sequence of the complex training sequence, and the service index sequence set by the service index sequence setting unit as the imaginary part sequence of the complex training sequence, in 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 resistance in the single frequency network. Interfering with various system parameters and business mode information of the wireless digital broadcast signal transmitter, X takes one of 512, 1024, and 2048;

8) Each anti-interference wireless digital broadcast signal transmitter in the single frequency network repeats the discrete sample value block of the complex training sequence formed on the time domain continuously for 4 times in the time domain to form the time domain embedded training sequence discrete sample value block, The length of the time-domain embedded training sequence discrete sample value block is equal to the length of the peak-to-average power ratio reduction space-frequency modulation time-domain discrete bit interleaving coded modulation data sample block, that is, K=4×X; when X is 512 , K is 2048, and 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 corresponding The frequency interval of subcarriers is 1KHz;

9) Each anti-interference wireless digital broadcasting signal transmitter in the single frequency network directly superimposes the peak-to-average power ratio, space-frequency modulation, time-domain discrete bit interleaving coded modulation data sample block, and time-domain embedded training sequence discrete sample block to form Domain embedding training sequence to reduce peak-to-average power ratio space-frequency modulation time-domain discrete bit interleaving coded modulation data sample block, as a frame body;

10) Each anti-interference wireless digital broadcasting signal transmitter in the single frequency network uses the cyclic prefix as a guard interval, that is, the frame header is inserted into the training sequence in the time domain, and the peak-to-average power ratio is reduced. That is, the frame body to 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 takes 1/16 of the size of K;

11) Each anti-jamming wireless digital broadcasting signal transmitter in the single frequency network uses a square root raised cosine roll-off filter to shape the signal pulse of the signal frame;

12) Each anti-interference wireless digital broadcast signal transmitter in the single frequency network up-converts the baseband signal to the carrier to form a radio frequency signal and transmit it to the wireless channel in the air;

13) The anti-jamming wireless digital broadcasting signal receiver in the single frequency network detects and receives the radio frequency signal sent by each anti-jamming wireless digital broadcasting signal transmitter in the single frequency network and down-converts it to form a baseband signal, and utilizes the cycle of the signal frame Prefix characteristics and structural characteristics of the signal frame are used for baseband signal reception processing.

According to the embodiment of the signal frame formation (assuming that there are N transmitters in the single frequency network) in the signal transmission process between the transmitter and the receiver of the single frequency network anti-jamming wireless digital broadcasting signal transmission method of the present invention, as shown in Figure 2 , the specific implementation is as follows:

The central data manager of the single frequency network 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 the input data bit stream.

The network data manager of the single frequency network forms the FFT bit interleaving coded modulation data block in the frequency domain through the multi-code rate punctured convolution coding, bit interleaving and symbol modulation of the input data bit stream; the multi-code rate punctured convolution coding The encoding rate is one of 1/4, 1/2, 5/8, 3/4 and 7/8, the bit interleaving adopts random interleaving, and the symbol modulation is one of QPSK, 16QAM, 32QAM and 64QAM. The symbol constellation map mapping method adopts Gray code mapping; the space-frequency encoder with a code rate of 1 is used to modulate the FFT bit interleaved coded modulation data block formed in the frequency domain to each anti-jamming wireless digital broadcasting signal transmission in the single frequency network Form space-frequency modulation FFT bit interleaving coding modulation data blocks on the machine branch, and adjust the time synchronization of each anti-jamming wireless digital broadcast signal transmitter branch to ensure that all transmitters in the network interleave space-frequency modulation FFT bits at the same time The coded modulation data block is processed; then it is transformed into a space-frequency modulation time-domain discrete bit interleaved coded modulation data sample block by IFFT, and the peak-to-average power ratio with the lowest peak-to-average power ratio is generated and selected by the peak-to-average power ratio adjustment unit. The power ratio space-frequency modulation time-domain discrete bit interleaving coding modulates the data sample block and at the same time sends the corresponding generation mode information to the service index sequence setting unit. Space-frequency modulation FFT bit-interleaved coded modulation data block is composed of sub-carriers. The length of space-frequency modulation FFT bit-interleaving coding 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 subcarrier is 2KHz; when X is 2048, the corresponding K is 8192, and the frequency interval of the corresponding subcarrier is 1KHz. Each anti-jamming wireless digital broadcasting signal transmitter in the single frequency network uses the training sequence as the real part sequence of the complex training sequence and the service index sequence as the imaginary part sequence of the complex training sequence, and forms discrete samples of the complex training sequence in the time domain. value block, and then repeat it four times continuously in the time domain to form a time domain embedded training sequence discrete sample value block. 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 the training sequence and service index sequence of each anti-interference wireless digital broadcast signal transmitter in the single frequency network, it is composed of a series of 1 or -1, which has 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 a Walsh sequence as an orthogonal sequence, a Hadamard sequence or an orthogonal sequence generated by other means; Each different service index sequence contains and uniquely expresses each system parameter and service mode information of each anti-jamming wireless digital broadcasting signal transmitter in the single frequency network. Each anti-interference wireless digital broadcasting signal transmitter in the single frequency network directly superimposes the discrete sample value blocks of the peak-to-average power ratio, space-frequency modulation, time-domain discrete bit interleaving coding modulation, and time-domain embedded training sequence discrete sample blocks to form time-domain embedding Training sequence reduced peak-to-average power ratio space-frequency modulation time-domain discrete bit-interleaved coded modulation data sample block, as a frame body; training sequence reduced peak-to-average power ratio space-frequency modulation time-domain discrete bit-interleaved coded modulated data sample is embedded in the time domain A cyclic prefix is inserted into the 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. Each anti-interference wireless digital broadcasting signal transmitter in the single frequency network uses a square root raised cosine roll-off filter to perform pulse shaping on 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.

Each anti-interference wireless digital broadcasting signal transmitter in the single frequency network 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 anti-jamming wireless digital broadcasting signal receiver in the single frequency network detects and receives the radio frequency signal sent by each anti-jamming wireless digital broadcasting signal transmitter in the single frequency network and down-converts it to form a baseband signal, using the cyclic prefix characteristic of the signal frame The baseband signal receiving process is carried out according to the structural characteristics of the signal frame, including the time-frequency domain joint iterative separation processing of the signal frame header and the 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 single frequency network anti-interference wireless digital broadcast signal transmission method is characterized in that it comprises the following steps:

1) the centre data manager of single frequency network 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 network data management device of single frequency network will be imported the data bit multi code Rate of Chinese character of flowing through and delete surplus convolutional encoding, Bit Interleave, code element and be modulated at and form FFT Bit Interleave coding modulation data piece on the frequency domain, and the length of FFT Bit Interleave coding modulation data piece is K;

3) to adopt code check be that FFT Bit Interleave coding modulation data piece that 1 space-frequency coding device will form on frequency domain is modulated to form on each anti-interference wireless digital broadcast signal transmitter branches in the single frequency network and emptyly frequently modulates FFT Bit Interleave coding modulation data piece to the network data management device of single frequency network, and the time synchronized of adjusting each anti-interference wireless digital broadcast signal transmitter branches is all modulated FFT Bit Interleave coding modulation data piece frequently to sky at one time and handled to guarantee all transmitters in the network;

4) each anti-interference wireless digital broadcast signal transmitter in the single frequency network adopts IFFT that sky is modulated FFT Bit Interleave coding modulation data piece frequently and is transformed to the empty time domain discrete Bit Interleave coding modulation data sample value piece D that frequently modulates _Total

5) each anti-interference wireless digital broadcast signal transmitter in the single frequency network is modulated sky frequently time domain discrete Bit Interleave coding modulation data sample value piece in order and is divided equally into two, the empty sub-piece D of time domain discrete Bit Interleave coding modulation data sample value that frequently modulates ₁Frequently modulate the sub-piece D of time domain discrete Bit Interleave coding modulation data sample value with sky ₂, D _Tota1=[D ₁, D ₂];

6) each anti-interference wireless digital broadcast signal transmitter in the single frequency network is modulated the sub-piece D of time domain discrete Bit Interleave coding modulation data sample value by the peak-to-average power ratio adjustment unit frequently to sky ₁, the empty sub-piece D of time domain discrete Bit Interleave coding modulation data sample value that frequently modulates ₂Carry out that signal adds, subtracts, conjugate operation is handled and the synthetic new again empty time domain discrete Bit Interleave coding modulation data sample value piece D that frequently modulates _New, the new empty time domain discrete Bit Interleave coding modulation data sample value piece D that frequently modulates _NewAdopt following generate pattern to obtain, generate pattern 1 is D _New=[D ₁, D ₂], generate pattern 2 is $D_{\mathrm{new}}=[D_1,\sqrt{1/2}(D_1+D_2)],$ 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 $D_{\mathrm{new}}=[\sqrt{1/2}(D_1-D_2),D_2],$ 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 $D_{\mathrm{new}}=[\sqrt{1/2}({D^{*}}_1-D_2),D_2],$ Generate pattern 12 is $D_{\mathrm{new}}=[\sqrt{1/2}({D^{*}}_1+D_2),\sqrt{1/2}({D^{*}}_1-D_2)],$ Relatively 12 kinds of synthetic empty frequencies of generate pattern are modulated time domain discrete Bit Interleave coding modulation data sample value piece D _New, choose the empty frequency of peak-to-average power ratio that falls that wherein has minimum peak-to-average power ratio and modulate time domain discrete Bit Interleave coding modulation data sample value piece

And the empty time domain discrete Bit Interleave coding modulation data sample value piece of frequently modulating of peak-to-average power ratio will fall

The corresponding generate pattern information that adopts send to the operational indicator sequence unit be set, wherein, D ^* ₁Expression is modulated the sub-piece D of time domain discrete Bit Interleave coding modulation data sample value frequently to sky ₁Each empty modulate that time domain discrete Bit Interleave coding modulation data sample value carries out that conjugate operation is handled frequently and the empty sub-piece of time domain discrete Bit Interleave coding modulation data sample value of frequently modulating that obtains;

7) each anti-interference wireless digital broadcast signal transmitter in the single frequency network is with the real part sequence of training sequence as sequence of plural training, the operational indicator sequence is provided with the imaginary part sequence of the set operational indicator sequence in unit as sequence of plural training, on time domain, constitute the discrete sample block of sequence of plural training, training sequence, the operational indicator sequence, the length of the discrete sample block of 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 each anti-interference wireless digital broadcast signal transmitter in the single frequency network;

8) each anti-interference wireless digital broadcast signal transmitter in the single frequency network will repeat 4 times continuously and form time domain embedding training sequence discrete sample block on time domain in the discrete sample block of the sequence of plural training that constitutes on the time domain, time domain embeds the length of training sequence discrete sample block and falls the empty length numerically equal of frequently modulating time domain discrete Bit Interleave coding modulation data sample value piece of peak-to-average power ratio, i.e. K=4 * X;

9) each anti-interference wireless digital broadcast signal transmitter in the single frequency network will fall the empty time domain discrete Bit Interleave coding modulation data sample value piece, time domain frequently modulated of peak-to-average power ratio and embed training sequence discrete sample block and directly superpose and form time domain and embed training sequence and fall that peak-to-average power ratio is empty frequently modulates time domain discrete Bit Interleave coding modulation data sample value piece, as frame;

10) each anti-interference wireless digital broadcast signal transmitter in the single frequency network at interval is that frame head inserts time domain and embeds training sequence and fall peak-to-average power ratio empty frequently to modulate time domain discrete Bit Interleave coding modulation data sample value piece be frame with Cyclic Prefix as protection, to form signal frame, the length of Cyclic Prefix is C;

11) each anti-interference wireless digital broadcast signal transmitter in the single frequency network adopts square root raised cosine filter that the signal pulse of signal frame is shaped;

12) each anti-interference wireless digital broadcast signal transmitter in the single frequency network forms emission of radio frequency signals to the on-air radio channel with the baseband signal up-conversion to carrier wave;

13) the anti-interference wireless digital broadcasting signal receiver in the single frequency network detect to receive radiofrequency signal that each anti-interference wireless digital broadcast signal transmitter in the single frequency network sent 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 single frequency network anti-interference wireless digital broadcast signal transmission method of claim 1, it is characterized in that: the length X of the discrete sample block of the training sequence of each anti-interference wireless digital broadcast signal transmitter in the described single frequency network, operational indicator sequence, sequence of plural training is got in 512,1024,2048.

3. by the single frequency network anti-interference wireless digital broadcast signal transmission method 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 single frequency network anti-interference wireless digital broadcast signal transmission method of claim 2, it is characterized in that: described training sequence, operational indicator sequence have orthogonality each other.

5. press the single frequency network anti-interference wireless digital broadcast signal transmission method of claim 1, it is characterized in that: describedly the input data are carried out multi code Rate of Chinese character delete the multi code Rate of Chinese character of surplus convolutional encoding, Bit Interleave, code element modulation treatment to delete the encoding rate of surplus convolutional encoding be in 1/4,1/2,5/8,3/4 and 7/8 one, 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.

6. by the single frequency network anti-interference wireless digital broadcast signal transmission method of claim 1, it is characterized in that: described empty frequency is modulated FFT Bit Interleave coding modulation data piece and 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.

7. by the single frequency network anti-interference wireless digital broadcast signal transmission method 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.

8. press the single frequency network anti-interference wireless digital broadcast signal transmission method of claim 1, it is characterized in that: the baseband signal that described single frequency network anti-interference wireless digital broadcasting signal receiver is carried 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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