CN102244639B - Method for framing and modulating wireless multimedia broadcast signals - Google Patents

Abstract

The invention discloses a wireless multimedia broadcasting signal framing modulation method, which is a framing modulation scheme of mixing time domain and frequency domain. The signal generation mode and signal selection method of the wireless multimedia broadcasting signal framing modulation method of the present invention are easy to process and restore the original signal of the OFDM signal at the receiver end, and have low peak-to-average power ratio, short synchronization time, anti-channel fading, and Control multiple services and other advantages.

Description

A kind of framing modulation method of wireless multimedia broadcasting signal

technical field

The invention belongs to the field of wireless communication, and more specifically relates to a method for framing and modulating wireless multimedia broadcasting signals.

Background technique

At present, television broadcasting has gradually developed from analog to digital. Digital TV wireless multimedia broadcasting transmission system, as an important part of digital TV wireless multimedia broadcasting, the development of its related technologies is closely related to people's quality of life, and therefore has received extensive attention from people. Digital TV wireless multimedia broadcasting related technologies and related industries are industries with rapid development and good market prospects in the field of communication and computer. In terms of technologies related to digital TV wireless multimedia broadcasting, countries are currently focusing on how to provide low-cost, reliable and high-speed mobile solutions for digital TV wireless multimedia broadcasting in a complex wave propagation environment. The framing modulation technology of the wireless multimedia broadcasting signal transmitter is the key technology of the digital TV wireless multimedia broadcasting system, which 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 wireless multimedia 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.

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

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

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

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

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

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

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

U.Ladebusch and C.A.Liss. "Terrestrial DVB (DVB-T): A broadcast technology for stationary portable and mobile use," Proceedings of the IEEE, Special Issue on Global Digital Television: Technology and Emerging Services, pp.183-194, .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.

Contents of the invention

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

A kind of wireless multimedia broadcast signal framing modulation method that the present invention proposes is characterized in that it comprises the following steps:

1) The wireless multimedia broadcasting signal transmitter forms an FFT data block with its input data bit stream in the frequency domain, FFT represents fast discrete Fourier transform, and the length of the FFT data block is K;

2) The wireless multimedia broadcast signal transmitter uses IFFT to transform the FFT data block into a time-domain discrete data sample block D _total , and IFFT means inverse fast discrete Fourier transform;

3) The wireless multimedia broadcasting signal transmitter divides the time-domain discrete data sample value block into two equally in order, the time-domain discrete data sample value sub-block D ₁ and the time-domain discrete data sample value sub-block D ₂ , D _total = [D ₁ , _D2 ];

并将降峰均功率比时域离散数据样值块

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表示对时域离散数据样值子块D₁的各时域离散数据样值进行共轭运算处理而得到的时域离散数据样值子块；4) The wireless multimedia broadcasting signal transmitter performs signal addition, subtraction, and conjugate operation processing on the time-domain discrete data sample sub-block D ₁ and the time-domain discrete data sample sub-block D ₂ through the peak-to-average power ratio adjustment unit and recombines them The new time-domain discrete data sample block _Dnew , the new time-domain discrete data sample block _Dnew is obtained by the following generation mode, the generation mode 1 is _Dnew = [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 data sample block D _new synthesized by 12 generation modes, and select the time-domain discrete data sample block with the lowest peak-to-average power ratio

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

The corresponding generation mode information is sent to the service index sequence setting unit, wherein, D ^* ₁ represents the time domain obtained by performing conjugate operation processing on each time domain discrete data sample value of the time domain discrete data sample value sub-block D ₁ discrete data sample sub-blocks;

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

6) The wireless multimedia broadcasting signal transmitter repeats the discrete sample blocks of the complex training sequence formed in the time domain four times continuously in the time domain to form a time domain embedded training sequence discrete sample block, and the time domain embedded training sequence discrete sample value The block length is numerically equal to the length of the peak-to-average power ratio time-domain discrete data sample block, that is, K=4×X;

7) The wireless multimedia broadcasting signal transmitter directly superimposes the time-domain discrete data sample blocks with reduced peak-to-average power ratio and time-domain embedded training sequence discrete sample blocks to form time-domain embedded training sequence reduced peak-to-average power ratio time-domain discrete data samples block, as a frame body;

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

9) The wireless multimedia broadcasting signal transmitter uses a square root raised cosine roll-off filter to shape the signal pulse of the signal frame;

10) The wireless multimedia broadcasting signal transmitter up-converts the baseband signal to the carrier.

According to the above-mentioned wireless multimedia broadcast signal framing modulation method, it is characterized in that: the peak-to-average power ratio of the wireless multimedia broadcast signal transmitter is reduced by the time-domain discrete data sample block from the time-domain discrete data sample sub-block through specific 12 generation modes The signal addition, subtraction, and conjugate operation processing carried out are re-synthesized; the signal frame of the wireless multimedia broadcasting signal transmitter has a periodic time-domain embedded training sequence discrete sample block; the training sequence of the wireless multimedia broadcasting signal transmitter. The length X is one of 512, 1024, 2048, the length K of the corresponding FFT data block is 2048, 4096, 8192 respectively, the frequency intervals of the corresponding subcarriers are 4KHz, 2KHz, 1KHz respectively, and the corresponding cyclic prefix The length C is 1/4, 1/8, and 1/16 of the size of the FFT data block length K; the training sequence and service index sequence of the wireless multimedia 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 wireless multimedia broadcast signal transmitter are orthogonal to each other; each different service index sequence of the wireless multimedia broadcast signal transmitter contains and uniquely expresses each system of the wireless multimedia broadcast signal transmitter Parameters and business model information.

Features of the present invention:

The invention is a framing modulation scheme of mixing time domain and frequency domain. The generation mode of the time-domain discrete data sample block with reduced peak-to-average power ratio and the method for selecting the time-domain discrete data sample block with the lowest peak-to-average power ratio of the present invention can not only make full use of the maximum peak value of the OFDM signal The power is very high but the probability of high peak power signal is very low. When the number of subcarriers is large, the real part (or imaginary part) of the OFDM signal is a complex Gaussian random process and the amplitude obeys the characteristics of Rayleigh distribution. The generation mode used requires The amount of additional information sent 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 sub-carrier signal and will not generate additional nonlinear distortion. The signal frame of the wireless multimedia broadcasting signal transmitter has a periodic time-domain embedded training sequence discrete sample block, the training sequence and service index sequence of the wireless multimedia broadcasting signal transmitter have pseudo-random characteristics, the training of the wireless multimedia broadcasting signal transmitter Sequences and service index sequences are orthogonal to each other, and the time-domain embedded training sequence of the wireless multimedia broadcasting signal transmitter reduces the peak-to-average power ratio to the time-domain discrete data sample block. Blocks and time domain embedded training sequence discrete sample blocks are directly superimposed, which ensures that the wireless multimedia broadcasting signal receiver can achieve fast and accurate frame synchronization, frequency synchronization, time synchronization, channel transmission characteristic estimation, and phase noise and Reliable tracking of channel transfer characteristics. Inserting the cyclic prefix as a guard interval into time-domain embedded training sequence to reduce peak-to-average power ratio time-domain discrete data sample blocks to form a signal frame can reduce the interference between adjacent signal frames. Each different service index sequence of the wireless multimedia broadcasting signal transmitter contains and uniquely expresses the system parameters and business mode information of the wireless multimedia broadcasting signal transmitter, which can enable the digital TV wireless multimedia broadcasting transmission system to provide free TV broadcasting, paid TV broadcasting, confidential information transmission, multimedia value-added services, etc. can control multiple services to meet social needs. The framing modulation 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 and controllable multi-service digital TV wireless multimedia broadcast transmission.

Description of drawings

Fig. 1 is a schematic diagram of an embodiment of a transmitter of a wireless multimedia broadcasting signal framing modulation method according to the present invention.

Fig. 2 is a schematic diagram of an embodiment of a transmitter signal framing modulation according to a wireless multimedia broadcasting signal framing modulation 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 a certain transmitter of the wireless multimedia broadcasting signal framing modulation method proposed by the present invention, as shown in Figure 1, carry out according to the following steps:

1) The certain wireless multimedia broadcasting signal transmitter forms an FFT data block with its input data bit stream in the frequency domain, FFT represents fast discrete Fourier transform, and the length of the FFT data block is K;

2) The certain wireless multimedia broadcasting signal transmitter adopts IFFT to transform the FFT data block into a time-domain discrete data sample block D _total , and IFFT represents an inverse fast discrete Fourier transform;

3) The certain wireless multimedia broadcast signal transmitter divides the time-domain discrete data sample value block into two blocks in sequence, the time-domain discrete data sample value sub-block D ₁ and the time-domain discrete data sample value sub-block D ₂ , D _total = [D ₁ , D ₂ ];

并将降峰均功率比时域离散数据样值块

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表示对时域离散数据样值子块D₁的各时域离散数据样值进行共轭运算处理而得到的时域离散数据样值子块；4) The certain wireless multimedia broadcast signal transmitter performs signal addition, subtraction, and conjugate operation processing on the time-domain discrete data sample sub-block D ₁ and the time-domain discrete data sample sub-block D ₂ through the peak-to-average power ratio adjustment unit And re-synthesize a new time-domain discrete data sample block _Dnew , the new time-domain discrete data sample block _Dnew is obtained by the following generation mode, generation mode 1 is _Dnew = [D ₁ , D ₂ ], generation mode 2 for ${\mathrm{D.}}_{\mathrm{new}}=[{\mathrm{D.}}_1,\sqrt{1/2}({\mathrm{D.}}_1+{\mathrm{D.}}_2)],$ Generate schema 3 as ${\mathrm{D.}}_{\mathrm{new}}=[{\mathrm{D.}}_1,\sqrt{1/2}({\mathrm{D.}}_1-{\mathrm{D.}}_2)],$ Generate schema 4 as ${\mathrm{D.}}_{\mathrm{new}}=[\sqrt{1/2}({\mathrm{D.}}_1+{\mathrm{D.}}_2),{\mathrm{D.}}_2],$ Generate schema 5 as ${\mathrm{D.}}_{\mathrm{new}}=[\sqrt{1/2}({\mathrm{D.}}_1-{\mathrm{D.}}_2),{\mathrm{D.}}_2],$ Generate schema 6 as ${\mathrm{D.}}_{\mathrm{new}}=[\sqrt{1/2}({\mathrm{D.}}_1+{\mathrm{D.}}_2),\sqrt{1/2}({\mathrm{D.}}_1-{\mathrm{D.}}_2)],$ Generation mode 7 is D _new = [D ^* ₁ , D ₂ ], generation mode 8 is ${\mathrm{D.}}_{\mathrm{new}}=[{{\mathrm{D.}}^{*}}_1,\sqrt{1/2}({{\mathrm{D.}}^{*}}_1+{\mathrm{D.}}_2)],$ Generate schema 9 as ${\mathrm{D.}}_{\mathrm{new}}=[{{\mathrm{D.}}^{*}}_1,\sqrt{1/2}({{\mathrm{D.}}^{*}}_1-{\mathrm{D.}}_2)],$ Generate schema 10 as ${\mathrm{D.}}_{\mathrm{new}}=[\sqrt{1/2}({{\mathrm{D.}}^{*}}_1+{\mathrm{D.}}_2),{\mathrm{D.}}_2],$ Generate schema 11 as ${\mathrm{D.}}_{\mathrm{new}}=[\sqrt{1/2}({{\mathrm{D.}}^{*}}_1-{\mathrm{D.}}_2),{\mathrm{D.}}_2],$ Generate schema 12 as ${\mathrm{D.}}_{\mathrm{new}}=[\sqrt{1/2}({{\mathrm{D.}}^{*}}_1+{\mathrm{D.}}_2),\sqrt{1/2}({{\mathrm{D.}}^{*}}_1-{\mathrm{D.}}_2)],$ Compare the time-domain discrete data sample block D _new synthesized by 12 generation modes, and select the time-domain discrete data sample block with the lowest peak-to-average power ratio

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

The corresponding generation mode information is sent to the service index sequence setting unit, wherein, D ^* ₁ represents the time domain obtained by performing conjugate operation processing on each time domain discrete data sample value of the time domain discrete data sample value sub-block D ₁ discrete data sample sub-blocks;

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

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

7) The certain wireless multimedia broadcasting signal transmitter directly superimposes the time-domain discrete data sample block with reduced peak-to-average power ratio and the discrete sample value block of time-domain embedded training sequence to form a time-domain embedded training sequence with reduced peak-to-average power ratio time-domain discrete Data sample block, as a frame body;

8) The certain wireless multimedia broadcasting signal transmitter uses the cyclic prefix as a 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 discrete data sample block in the time domain, that is, the frame body, to form a signal frame, and the cyclic prefix The length is C; when X is 512, C is 1/4 of the size of K; when X is 1024, C is 1/8 of the size of K; when X is 2048, C is 1/16 of the size of K;

9) The certain wireless multimedia broadcasting signal transmitter uses a square root raised cosine roll-off filter to shape the signal pulse of the signal frame;

10) The certain wireless multimedia broadcasting signal transmitter up-converts the baseband signal to the carrier.

According to an embodiment of a certain transmitter signal framing modulation of the wireless multimedia broadcasting signal framing modulation method of the present invention, as shown in Figure 2, the specific implementation is as follows:

The certain wireless multimedia broadcast signal transmitter forms an FFT data block on its input data bit stream in the frequency domain, and then transforms it into a discrete data sample block in the time domain through IFFT, and generates and selects it through the peak-to-average power ratio adjustment unit Among them, the time-domain discrete data sample block with reduced peak-to-average power ratio with the lowest peak-to-average power ratio sends the corresponding generation mode information to the service index sequence setting unit at the same time.

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

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

As a wireless multimedia 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 wireless multimedia broadcasting signal transmitter.

The certain wireless multimedia broadcasting signal transmitter directly superimposes the time-domain discrete data sample block with reduced peak-to-average power ratio and the time-domain embedded training sequence discrete sample block to form a time-domain embedded training sequence with reduced peak-to-average power ratio time-domain discrete data sample The value block is used as a frame body; the cyclic prefix is inserted into the time domain discrete data sample block of the time domain embedding training sequence 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 At 2048, the corresponding C takes 1/16 of the size of K.

The certain wireless multimedia broadcasting signal transmitter adopts 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 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 (6)

1. A wireless multimedia broadcasting signal framing modulation method is characterized in that it comprises the following steps: 1) The wireless multimedia broadcast signal transmitter forms an FFT data block with its input data bit stream in the frequency domain, and the length of the FFT data block is K; 2) The wireless multimedia broadcasting signal transmitter adopts IFFT to transform the FFT data block into a time-domain discrete data sample value block D _total ; 3) The wireless multimedia broadcasting signal transmitter divides the time-domain discrete data sample value block into two equally in order, the time-domain discrete data sample value sub-block D ₁ and the time-domain discrete data sample value sub-block D ₂ , D _total = [D ₁ , _D2 ]; 4) The wireless multimedia broadcasting signal transmitter performs signal addition, subtraction, and conjugate operation processing on the time-domain discrete data sample sub-block D ₁ and the time-domain discrete data sample sub-block D ₂ through the peak-to-average power ratio adjustment unit and recombines them The new time-domain discrete data sample block _Dnew , the new time-domain discrete data sample block _Dnew is obtained by the following generation mode, the generation mode 1 is _Dnew = [D ₁ , D ₂ ], and the generation mode 2 is

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 ${\mathrm{D.}}_{\mathrm{new}}=[\sqrt{1/2}({{\mathrm{D.}}^{*}}_1-{\mathrm{D.}}_2),{\mathrm{D.}}_2],$ , generating schema 12 as ${\mathrm{D.}}_{\mathrm{new}}=[\sqrt{1/2}({{\mathrm{D.}}^{*}}_1+{\mathrm{D.}}_2),\sqrt{1/2}({{\mathrm{D.}}^{*}}_1-{\mathrm{D.}}_2\left)\right],$ Compare the time-domain discrete data sample block D _new synthesized by 12 generation modes, and select the time-domain discrete data sample block with the lowest peak-to-average power ratio

and reduce the peak-to-average power ratio time-domain discrete data sample block The corresponding generation mode information is sent to the service index sequence setting unit, wherein, D ^* ₁ represents the time domain obtained by performing conjugate operation processing on each time domain discrete data sample value of the time domain discrete data sample value sub-block D ₁ discrete data sample sub-blocks; 5) The wireless multimedia broadcasting signal transmitter uses the training sequence as the real part sequence of the complex training sequence, and uses the service index sequence set by the service index sequence setting unit as the imaginary part sequence of the complex training sequence to form the complex training sequence in the time domain Discrete sample value block, the length of the discrete sample value block of the training sequence, service index sequence, and complex training sequence is X, and the service index sequence contains and uniquely expresses various system parameters and service mode information of the wireless multimedia broadcasting signal transmitter; 6) The wireless multimedia broadcasting signal transmitter repeats the discrete sample blocks of the complex training sequence formed in the time domain four times continuously in the time domain to form a time domain embedded training sequence discrete sample block, and the time domain embedded training sequence discrete sample value The block length is numerically equal to the length of the peak-to-average power ratio time-domain discrete data sample block, that is, K=4×X; 7) The wireless multimedia broadcasting signal transmitter directly superimposes the time-domain discrete data sample blocks with reduced peak-to-average power ratio and time-domain embedded training sequence discrete sample blocks to form time-domain embedded training sequence reduced peak-to-average power ratio time-domain discrete data samples block, as a frame body; 8) The wireless multimedia broadcast signal transmitter uses the cyclic prefix as a guard interval, that is, inserts the frame header into the time domain, embeds the training sequence, reduces the peak-to-average power ratio, and the discrete data sample block in the time domain, that is, the frame body, to form a signal frame, and the length of the cyclic prefix is C ; 9) The wireless multimedia broadcasting signal transmitter uses a square root raised cosine roll-off filter to shape the signal pulse of the signal frame; 10) The wireless multimedia broadcasting signal transmitter up-converts the baseband signal to the carrier. 2. by the wireless multimedia broadcasting signal framing modulation method of claim 1, it is characterized in that: the length X of the discrete sample value block of the training sequence of described wireless multimedia broadcasting signal transmitter, service index sequence, complex number training sequence gets 512, One of 1024, 2048. 3. The wireless multimedia broadcast signal framing modulation method according to claim 2, characterized in that: said training sequence and service index sequence are composed of a series of 1 or -1, and have pseudo-random characteristics. 4. The wireless multimedia broadcast signal framing modulation method according to claim 2, characterized in that: the training sequence and the service index sequence are orthogonal to each other. 5. by the wireless multimedia broadcasting signal framing modulation method of claim 1, it is characterized in that: described FFT data block is made up of subcarrier; When X gets 512, subcarrier number gets 2048, and the frequency interval of subcarrier gets 4KHz; When X is 1024, the number of subcarriers is 4096, and the frequency interval of subcarriers is 2KHz; when X is 2048, the number of subcarriers is 8192, and the frequency interval of subcarriers is 1KHz. 6. by the wireless multimedia broadcasting signal framing modulation method of claim 1, it is characterized in that: the length C value of described cyclic prefix is relevant with X value; When X gets 512, C gets 1/4 of K size; When X takes 1024, C takes 1/8 of the size of K; when X takes 2048, C takes 1/16 of the size of K.

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