CN101778075B - Multimedia broadcast wireless signal anti-fading transmission method - Google Patents
Multimedia broadcast wireless signal anti-fading transmission method Download PDFInfo
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Abstract
The present invention discloses a multimedia broadcast wireless signal anti-fading transmission method. In the multimedia broadcast wireless signal anti-fading transmission method of the invention, after media data processing of multimedia data stream on a multimedia broadcast wireless transmitter terminal, bit stream RS coding, convolution interleaving, LDPC coding, code element modulation, constellation rotation, code element interleaving, frame body formation, time domain training sequence insertion framing, pulse shaping, and up-conversion to carrier waves, multimedia broadcast wireless signals form radio-frequency signals which are transmitted to an air wireless channel and received by a receiver terminal for processing signals transmitted by the multimedia broadcast wireless transmitter terminal. The multimedia broadcast wireless signal anti-fading transmission method has the advantages of short receiving synchronization time, anti-fading, high transmission efficiency, controllable multiple services and the like.
Description
Technical field
The invention belongs to wireless communication field, relate more specifically to a kind of multimedia broadcast wireless signal anti-fading transmission method.
Background technology
At present, wireless videocast develops to the digitlization direction gradually from simulation.The digital television broadcasting wireless transmitting system, as the wireless important component part of digital television broadcasting, its development of technologies, closely bound up with people's quality of life, and therefore be subjected to people's extensive concern especially.Digital television broadcasting wireless-related technologies and related industry thereof are that development is very fast in the Communications And Computer field, the industry of good market prospect.On the digital television broadcasting wireless-related technologies, the emphasis of various countries' concern at present is that how being complex wave, the wireless implementation of reliable high-speed mobile cheaply that provides of digital television broadcasting under the environment is provided.The digital television broadcasting Radio Transmission Technology is the key technology of digital television broadcasting wireless system, for whole system performance decisive role, is the object of everybody primary study.
Because the develop rapidly of Digital Signal Processing and integrated circuit technique, the system of OFDM (OFDM) technology realizes becoming more and more easier.Because of OFDM multi-carrier transmission technology has simple in structure, the availability of frequency spectrum high plurality of advantages such as becomes and extremely everybody concern and obtain deep research and the extensive use in numerous areas such as Xdsl, wide-band mobile communication, wideband wireless local area network, digital television broadcasting in the time of can resisting frequency selectivity and channel.
In the practical communication environment, the ofdm communication system performance is subjected to the influence of factors such as lock in time, clock jitter, channel fading, multi-user's common-channel interference.Anti fading channel coding technology and modulator approach are to realize the key technology of reliable ofdm communication.
Chnnel coding is the important component part of digital communication system.Along with the develop rapidly of modern information technologies, channel coding technology has become the indispensable technology in modern communications field.Embed redundancy symbol in information sequence, the effect of channel coding technology by redundancy symbol reduces signal and makes a mistake in transmission course, thereby improves the reliability of communication system.
Under multidiameter fading channel, can be by outer coding, interior coding, interweave and the cascade optimal design of modulation scheme reaches big as far as possible signal diversifying exponent number, so that in equaling or exceeding the symbol sebolic addressing of minimum free distance, obtain independent decline.The different coding form of cascade can make full use of the advantage of different coding technology; Between coding and code element modulation, insert bit interleaver, can be so that coding be relatively independent with modulated process and expand diversity order to different binary bits number from different multi-system symbolic numbers, thus make diversity order be improved significantly and under multidiameter fading channel, have the bit error performance of getting well.
Just be based on above background, the present invention is directed to the practical communication environment and propose a kind of multimedia broadcast wireless signal anti-fading transmission method, can satisfy the needs of High Data Rate may command multi-service digital television broadcasting wireless transmission.
Desire is done more deep understanding to the patent background can be with reference to following documents and materials:
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Summary of the invention
The present invention is directed to High Data Rate may command multi-service digital television broadcasting wireless transmission problem, proposed a kind of multimedia broadcast wireless signal anti-fading transmission method.
A kind of multimedia broadcast wireless signal anti-fading transmission method that the present invention proposes is characterized in that multimedia broadcast wireless signal is sent to the on-air radio channel and receives the signal that processing multimedia broadcasting transmitting set end is sent by receiver end through following steps at multimedia broadcasting transmitting set end:
1) multimedia broadcasting transmitting set end converts the multi-medium data media data processor of flowing through to data bit flow;
2) multimedia broadcasting transmitting set end will be imported the data bit RS coding (Reed-Solomon that flows through, RS), convolutional interleave, LDPC coding (Low Density Parity Check, LDPC), further on frequency domain, form the cascade interweaved coding modulation data piece of FFT (length (symbol numbers) of the cascade interweaved coding modulation data piece of FFT is K) after the code element modulation, constellation rotation, symbol interleave;
3) multimedia broadcasting transmitting set end adopts IFFT (fast discrete Fourier inverse transformation) the cascade interweaved coding modulation data piece of FFT to be transformed to the discrete cascade interweaving encoding modulating data sample value piece of time domain;
4) multimedia broadcasting transmitting set end as protecting the discrete cascade interweaving encoding modulating data sample value piece that is inserted into time domain at interval, forms the discrete cascade interweaving encoding modulating data sample value piece of time domain cyclic prefix (length of the discrete cascade interweaving encoding modulating data sample value piece of time domain cyclic prefix is (K+C)) with Cyclic Prefix (length of Cyclic Prefix is C);
5) multimedia broadcasting transmitting set end forms frame (length of frame is L, L=4 * (K+C)) with the discrete cascade interweaving encoding modulating data sample value piece of 4 continuous time domain cyclic prefix;
6) multimedia broadcasting transmitting set end as the real part sequence of sequence of plural training, with the imaginary part sequence of operational indicator sequence as sequence of plural training, constitutes the discrete sample block (length of the discrete sample block of training sequence, operational indicator sequence, sequence of plural training all is X) of sequence of plural training with training sequence on time domain;
7) multimedia broadcasting transmitting set end is inserted into frame with the discrete sample block (as frame head) of the sequence of plural training that constitutes on the time domain, to form signal frame;
8) multimedia broadcasting transmitting set end adopts square root raised cosine filter that the signal pulse of signal frame is shaped;
9) multimedia broadcasting transmitting set end forms emission of radio frequency signals to the on-air radio channel with the baseband signal up-conversion to carrier wave;
10) receiver end receives and handles the signal that multimedia broadcasting transmitting set end is sent.
Multimedia broadcast wireless signal anti-fading transmission method according to above-mentioned is characterized in that: multimedia broadcasting transmitting set end converts the multi-medium data media data processor of flowing through to data bit flow; Multimedia broadcasting transmitting set end carries out RS coding (Reed-Solomon to the input data bit flow, RS), convolutional interleave, LDPC (the Low Density Parity Check that encodes, LDPC), the code element modulation, constellation rotation, further on frequency domain, form the cascade interweaved coding modulation data piece of FFT after the symbol interleave, the RS coding combines with convolutional interleave and has very strong antiburst error ability, wherein, the encoding rate of LDPC coding is 1/4,1/2,5/8, in 3/4 and 7/8 one, code element is modulated to QPSK, 16QAM, 64QAM, a kind of with among the 256QAM, symbol constellations figure mapping mode adopts the Gray code mapping, the constellation rotation angle of QPSK symbol constellations is 22.5 degree, the constellation rotation angle of 16QAM symbol constellations is 11.25 degree, the constellation rotation angle of 64QAM symbol constellations is 5.626 degree, the constellation rotation angle of 256QAM symbol constellations is 2.8125 degree, and symbol interleave adopts the random interleaving mode; Has periodic time-domain training sequence discrete sample block in the signal frame of multimedia broadcasting transmitting set end; Length (symbol numbers) X of the training sequence of multimedia broadcasting transmitting set end is 512; Length (symbol numbers) K (sub-carrier number) of the cascade interweaved coding modulation data piece of FFT of multimedia broadcasting transmitting set end gets in 2048,4096,8192, the frequency interval of corresponding subcarrier is respectively 4KHz, 2KHz, 1KHz, and corresponding circulating prefix-length C is respectively 1/4,1/8,1/16 of the cascade interweaved coding modulation data block length of FFT K size; The training sequence of multimedia broadcasting transmitting set end, operational indicator sequence are formed by a series of 1 or-1, have pseudo-random characteristics; Training sequence, the operational indicator sequence of multimedia broadcasting transmitting set end have orthogonality each other; Each different operational indicator sequence of multimedia broadcasting transmitting set end is comprising and unique each system parameters and business model information of expressing the multimedia broadcasting transmitting set; Receiver end receives handles the signal that radio multimedium broadcast transmitter end is sent.
Characteristics of the present invention:
The present invention is the anti-fading signal diversifying transmission plan that a kind of time-domain and frequency-domain mixes.Has periodic time-domain training sequence discrete sample block in the signal frame of multimedia broadcasting transmitting set end, the training sequence of multimedia broadcasting transmitting set end, the operational indicator sequence has pseudo-random characteristics, the training sequence of multimedia broadcasting transmitting set end, the operational indicator sequence has orthogonality each other, multimedia broadcasting transmitting set end is inserted into frame with the discrete sample block (as frame head) of the sequence of plural training that constitutes on the time domain and forms signal frame, and these have guaranteed that multimedia broadcasting wireless receiver end can realize frame synchronization fast and accurately, Frequency Synchronization, time synchronized, channel transfer characteristic is estimated, and phase noise and channel transfer characteristic reliably followed the tracks of.Multimedia broadcasting transmitting set end forms the discrete cascade interweaving encoding modulating data sample value piece of time domain cyclic prefix with Cyclic Prefix as the discrete cascade interweaving encoding modulating data sample value piece that protection is inserted into time domain at interval, can reduce the interference effect between the adjacent signals data sample piece.Multimedia broadcasting transmitting set end adopts and to encode outward, interweaves, the cascade optimal design of interior coding, modulation, constellation rotation, interleaving scheme is carried out cascade interweaved coded modulation to the input data and improved signal diversifying exponent number and anti-interference noise error correcting capability, make communication system under multidiameter fading channel, have good bit error performance, make communication system have anti-fading property the transmission environment background.Multimedia broadcasting transmitting set end forms the efficient that frame can be carried multi-media broadcasting system with the discrete cascade interweaving encoding modulating data sample value piece of 4 continuous time domain cyclic prefix.The code element modulation of multimedia broadcasting transmitting set end provides the signal diversifying effect with constellation rotation.Each different operational indicator sequence of multimedia broadcasting transmitting set end is comprising and unique each system parameters and business model information of expressing the multimedia broadcasting transmitting set, the multimedia broadcasting wireless transmitting system can satisfy social needs so that can provide may command multi-services such as free television broadcasting, paid television broadcasting, security information transmission, multimedia value-added service.Multimedia broadcast wireless signal anti-fading transmission method of the present invention have receive lock in time short, clock jitter is little, anti-channel fading, anti-channel disturbance, High Data Rate may command multi-service digital television broadcasting wireless transmission can be provided and the transmission environment background be had plurality of advantages such as anti-fading property.
Description of drawings
Fig. 1 is the embodiment schematic diagram according to signal transmission between certain transmitter and receiver of multimedia broadcast wireless signal anti-fading transmission method of the present invention.
Fig. 2 is the embodiment schematic diagram that forms according to signal frame in the signals transmission between certain transmitter and receiver of multimedia broadcast wireless signal anti-fading transmission method of the present invention.
Fig. 3 is the embodiment schematic diagram according to the constellation rotation method that the QPSK code element is modulated, the 16QAM code element is modulated of certain multimedia broadcasting transmitting set end of multimedia broadcast wireless signal anti-fading transmission method of the present invention.
Embodiment
Below in conjunction with accompanying drawing specific embodiments of the invention are described in detail.
The embodiment of signal transmission between certain transmitter and receiver of the multimedia broadcast wireless signal anti-fading transmission method that proposes according to the present invention, as shown in Figure 1, multimedia broadcast wireless signal is sent to the on-air radio channel and receives the signal that processing multimedia broadcasting transmitting set end is sent by receiver end through following steps at multimedia broadcasting transmitting set end:
1) this certain multimedia broadcasting transmitting set end converts the multi-medium data media data processor of flowing through to data bit flow;
2) this certain multimedia broadcasting transmitting set end will be imported the data bit RS coding (Reed-Solomon that flows through, RS), convolutional interleave (the RS coding of multimedia broadcasting transmitting set end combines with convolutional interleave and has very strong antiburst error ability), LDPC (the Low Density ParityCheck that encodes, LDPC) (the data bit of the multimedia broadcasting transmitting set end RS coding (Reed-Solomon that flows through, RS), the encoding rate of the LDPC coding behind the convolutional interleave is 1/4,1/2,5/8, in 3/4 and 7/8 one), code element modulation (the data bit of the multimedia broadcasting transmitting set end RS coding (Reed-Solomon that flows through, RS), convolutional interleave, code element behind the LDPC coding is modulated to QPSK, 16QAM, 64QAM, a kind of with among the 256QAM, symbol constellations figure mapping mode adopts the Gray code mapping), (the constellation rotation angle of QPSK symbol constellations is 22.5 degree to constellation rotation, the constellation rotation angle of 16QAM symbol constellations is 11.25 degree, the constellation rotation angle of 64QAM symbol constellations is 5.626 degree, and the constellation rotation angle of 256QAM symbol constellations is 2.8125 degree), (length (symbol numbers) of the cascade interweaved coding modulation data piece of FFT is K further to form the cascade interweaved coding modulation data piece of FFT after the symbol interleave (symbol interleave adopts the random interleaving mode) on frequency domain; Length (symbol numbers) K (sub-carrier number) of the cascade interweaved coding modulation data piece of FFT gets in 2048,4096,8192; Get 2048 when the length K (sub-carrier number) of the cascade interweaved coding modulation data piece of FFT, the frequency interval of corresponding subcarrier is got 4KHz; Get 4096 when the length K (sub-carrier number) of the cascade interweaved coding modulation data piece of FFT, the frequency interval of corresponding subcarrier is got 2KHz; Get 8192 when the length K (sub-carrier number) of the cascade interweaved coding modulation data piece of FFT, the frequency interval of corresponding subcarrier is got 1KHz);
3) this certain multimedia broadcasting transmitting set end adopts IFFT (fast discrete Fourier inverse transformation) the cascade interweaved coding modulation data piece of FFT to be transformed to the discrete cascade interweaving encoding modulating data sample value piece of time domain;
4) (length of Cyclic Prefix is C to this certain multimedia broadcasting transmitting set end with Cyclic Prefix; When the length K (sub-carrier number) of the cascade interweaved coding modulation data piece of FFT gets 2048, corresponding circulating prefix-length C is 1/4 of the cascade interweaved coding modulation data block length of a FFT K size; When the length K (sub-carrier number) of the cascade interweaved coding modulation data piece of FFT gets 4096, corresponding circulating prefix-length C is 1/8 of the cascade interweaved coding modulation data block length of a FFT K size; When the length K (sub-carrier number) of the cascade interweaved coding modulation data piece of FFT gets 8192, corresponding circulating prefix-length C be the cascade interweaved coding modulation data block length of FFT K size 1/16) be inserted at interval the discrete cascade interweaving encoding modulating data sample value piece of time domain as protection, form the discrete cascade interweaving encoding modulating data sample value piece of time domain cyclic prefix (length of the discrete cascade interweaving encoding modulating data sample value piece of time domain cyclic prefix is (K+C));
5) this certain multimedia broadcasting transmitting set end forms frame (length of frame is L, L=4 * (K+C)) with the discrete cascade interweaving encoding modulating data sample value piece of 4 continuous time domain cyclic prefix;
6) as the real part sequence of sequence of plural training, with the imaginary part sequence of operational indicator sequence as sequence of plural training, (length of the discrete sample block of training sequence, operational indicator sequence, sequence of plural training all is X to the discrete sample block of formation sequence of plural training to this certain multimedia broadcasting transmitting set end on time domain with training sequence; The length of training sequence (symbol numbers) X gets 512);
7) multimedia broadcasting transmitting set end is inserted into frame with the discrete sample block (as frame head) of the sequence of plural training that constitutes on the time domain, to form signal frame;
8) this certain multimedia broadcasting transmitting set end adopts square root raised cosine filter that the signal pulse of signal frame is shaped;
9) this certain multimedia broadcasting transmitting set end forms emission of radio frequency signals to the on-air radio channel with the baseband signal up-conversion to carrier wave;
10) this certain receiver end receives and handles the signal that multimedia broadcasting transmitting set end is sent.
Embodiment according to signal frame in the signals transmission between certain transmitter and receiver of multimedia broadcast wireless signal anti-fading transmission method of the present invention forms, as shown in Figure 2, specifically implement as follows:
This certain multimedia broadcasting transmitting set end converts the multi-medium data media data processor of flowing through to data bit flow.
This certain multimedia broadcasting transmitting set end will be imported the data bit RS coding (Reed-Solomon that flows through, RS), convolutional interleave, LDPC (the Low Density Parity Check that encodes, LDPC), further on frequency domain, form the cascade interweaved coding modulation data piece of FFT after the code element modulation, constellation rotation, symbol interleave, through IFFT it is transformed to the discrete cascade interweaving encoding modulating data sample value piece of time domain again.
The cascade interweaved coding modulation data piece of FFT is made up of subcarrier.The length (symbol numbers) of the cascade interweaved coding modulation data piece of FFT is K; K (sub-carrier number) gets in 2048,4096,8192; Get 2048 when the length K (sub-carrier number) of the cascade interweaved coding modulation data piece of FFT, the frequency interval of corresponding subcarrier is got 4KHz; Get 4096 when the length K (sub-carrier number) of the cascade interweaved coding modulation data piece of FFT, the frequency interval of corresponding subcarrier is got 2KHz; Get 8192 when the length K (sub-carrier number) of the cascade interweaved coding modulation data piece of FFT, the frequency interval of corresponding subcarrier is got 1KHz.
This certain multimedia broadcasting transmitting set end as protecting the discrete cascade interweaving encoding modulating data sample value piece that is inserted into time domain at interval, forms the discrete cascade interweaving encoding modulating data sample value piece of time domain cyclic prefix with Cyclic Prefix.
Length as protection Cyclic Prefix at interval is C; When the length K (sub-carrier number) of the cascade interweaved coding modulation data piece of FFT gets 2048, corresponding circulating prefix-length C is 1/4 of the cascade interweaved coding modulation data block length of a FFT K size; When the length K (sub-carrier number) of the cascade interweaved coding modulation data piece of FFT gets 4096, corresponding circulating prefix-length C is 1/8 of the cascade interweaved coding modulation data block length of a FFT K size; When the length K (sub-carrier number) of the cascade interweaved coding modulation data piece of FFT gets 8192, corresponding circulating prefix-length C is 1/16 of the cascade interweaved coding modulation data block length of a FFT K size.
This certain multimedia broadcasting transmitting set end forms frame with the discrete cascade interweaving encoding modulating data sample value piece of 4 continuous time domain cyclic prefix.
This certain multimedia broadcasting transmitting set end as the real part sequence of sequence of plural training, with the imaginary part sequence of operational indicator sequence as sequence of plural training, constitutes the discrete sample block of sequence of plural training with training sequence on time domain.
The length of the discrete sample block of training sequence, operational indicator sequence, sequence of plural training is X all, and X gets 512.
Training sequence, operational indicator sequence as multimedia broadcasting transmitting set end are formed by a series of 1 or-1, have pseudo-random characteristics, and training sequence, operational indicator sequence have orthogonality each other.The training sequence that satisfies above-mentioned feature can be by realizing as one group of displacement m sequence of a kind of specific type of pseudo-random number sequence with as the walsh sequence of orthogonal sequence, Hadamard sequences or by the orthogonal sequence that other modes produce.
Each different operational indicator sequence is comprising and unique each system parameters and business model information of expressing multimedia broadcasting transmitting set end.
This certain multimedia broadcasting transmitting set end is inserted into frame with the discrete sample block (as frame head) of the sequence of plural training that constitutes on the time domain, to form signal frame.
This certain multimedia broadcasting transmitting set end adopts square root raised cosine filter that the signal of signal frame is carried out pulse shaping.When K got 2048, the rolloff-factor that corresponding signal to signal frame carries out the square root raised cosine filter of pulse shaping got 0.1; When K got 4096, the rolloff-factor that corresponding signal to signal frame carries out the square root raised cosine filter of pulse shaping got 0.05; When K got 8192, the rolloff-factor that corresponding signal to signal frame carries out the square root raised cosine filter of pulse shaping got 0.025.
This certain multimedia broadcasting transmitting set end forms emission of radio frequency signals to the on-air radio channel with the baseband signal up-conversion to carrier wave.
This certain receiver end receives handles the signal that multimedia broadcasting transmitting set end is sent.
The embodiment of the QPSK code element modulation of certain multimedia broadcasting transmitting set end of the multimedia broadcast wireless signal anti-fading transmission method that proposes according to the present invention, the constellation rotation method of 16QAM code element modulation, the symbol constellations figure mapping mode of the QPSK code element of this certain multimedia broadcasting transmitting set end modulation as shown in Figure 3,, the modulation of 16QAM code element adopts the Gray code mapping; The constellation rotation angle of QPSK symbol constellations is 22.5 degree, and the constellation rotation angle of 16QAM symbol constellations is 11.25 degree.
In conjunction with the accompanying drawings specific embodiments of the invention are had been described in detail above, but the present invention is not limited to the foregoing description, under the spirit and scope situation of the claim that does not break away from the application, those skilled in the art can make various modifications or remodeling.
Claims (9)
1. multimedia broadcast wireless signal anti-fading transmission method is characterized in that multimedia broadcast wireless signal is sent to the on-air radio channel and is received by receiver end through following steps at multimedia broadcasting transmitting set end to handle the signal that multimedia broadcasting transmitting set end is sent:
1) multimedia broadcasting transmitting set end converts the multi-medium data media data processor of flowing through to data bit flow;
2) multimedia broadcasting transmitting set end will be imported flow through RS coding of data bit, convolutional interleave, the LDPC coding, the code element modulation, constellation rotation, further on frequency domain, form the cascade interweaved coding modulation data piece of FFT after the symbol interleave, RS represents Reed-Solomon, LDPC represents Low Density Parity Check, FFT represents the fast discrete Fourier conversion, the length of the cascade interweaved coding modulation data piece of FFT is K, code element is modulated to QPSK, 16QAM, a kind of among 64QAM and the 256QAM, the symbol constellations figure mapping mode of code element modulation adopts the Gray code mapping, the constellation rotation angle of QPSK symbol constellations is 22.5 degree, the constellation rotation angle of 16QAM symbol constellations is 11.25 degree, the constellation rotation angle of 64QAM symbol constellations is 5.626 degree, and the constellation rotation angle of 256QAM symbol constellations is 2.8125 degree;
3) multimedia broadcasting transmitting set end adopts IFFT that the cascade interweaved coding modulation data piece of FFT is transformed to the discrete cascade interweaving encoding modulating data sample value piece of time domain, and IFFT represents the fast discrete Fourier inverse transformation;
4) multimedia broadcasting transmitting set end is inserted into Cyclic Prefix as protection the discrete cascade interweaving encoding modulating data sample value piece of time domain at interval, form the discrete cascade interweaving encoding modulating data sample value piece of time domain cyclic prefix, the length of Cyclic Prefix is C, and the length of the discrete cascade interweaving encoding modulating data sample value piece of time domain cyclic prefix is K+C;
5) multimedia broadcasting transmitting set end forms frame with the discrete cascade interweaving encoding modulating data sample value piece of 4 continuous time domain cyclic prefix, and the length of frame is L, L=4 * (K+C);
6) multimedia broadcasting transmitting set end with training sequence as the real part sequence of sequence of plural training, with the imaginary part sequence of operational indicator sequence as sequence of plural training, on time domain, constitute the discrete sample block of sequence of plural training, the operational indicator sequence is comprising and unique each system parameters and business model information of expressing the multimedia broadcasting transmitting set, and the length of the discrete sample block of training sequence, operational indicator sequence, sequence of plural training all is X;
7) multimedia broadcasting transmitting set end is inserted into frame with the discrete sample block of the sequence of plural training that constitutes on the time domain as frame head, to form signal frame;
8) multimedia broadcasting transmitting set end adopts square root raised cosine filter that the signal pulse of signal frame is shaped;
9) multimedia broadcasting transmitting set end forms emission of radio frequency signals to the on-air radio channel with the baseband signal up-conversion to carrier wave;
10) receiver end receives and handles the signal that multimedia broadcasting transmitting set end is sent.
2. by a kind of multimedia broadcast wireless signal anti-fading transmission method of claim 1, it is characterized in that: the flow through encoding rate of the LDPC coding behind RS coding, the convolutional interleave of the data bit of described multimedia broadcasting transmitting set end is in 1/4,1/2,5/8,3/4 and 7/8 one.
3. by a kind of multimedia broadcast wireless signal anti-fading transmission method of claim 1, it is characterized in that: the symbol interleave of described multimedia broadcasting transmitting set end adopts the random interleaving mode.
4. by a kind of multimedia broadcast wireless signal anti-fading transmission method of claim 1, it is characterized in that: the cascade interweaved coding modulation data piece of the FFT of described multimedia broadcasting transmitting set end is made up of subcarrier; Sub-carrier number K gets in 2048,4096,8192.
5. by a kind of multimedia broadcast wireless signal anti-fading transmission method of claim 4, it is characterized in that: when K got 2048, the frequency interval of subcarrier was got 4KHz; When K got 4096, the frequency interval of subcarrier was got 2KHz; When K got 8192, the frequency interval of subcarrier was got 1KHz.
6. by a kind of multimedia broadcast wireless signal anti-fading transmission method of claim 1, it is characterized in that: when K got 2048, C got 1/4 of K size; When K got 4096, C got 1/8 of K size; When K got 8192, C got 1/16 of K size.
7. by a kind of multimedia broadcast wireless signal anti-fading transmission method of claim 1, it is characterized in that: the length X of the discrete sample block of the training sequence of described multimedia broadcasting transmitting set end, operational indicator sequence, sequence of plural training all gets 512.
8. by a kind of multimedia broadcast wireless signal anti-fading transmission method of claim 1, it is characterized in that: the training sequence of described multimedia broadcasting transmitting set end, operational indicator sequence are formed by a series of 1 or-1, and are had pseudo-random characteristics.
9. by a kind of multimedia broadcast wireless signal anti-fading transmission method of claim 1, it is characterized in that: training sequence, the operational indicator sequence of described multimedia broadcasting transmitting set end have orthogonality each other.
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| CN102263736B (en) * | 2011-08-22 | 2013-11-06 | 宁波大学 | Anti-fading digital broadcast wireless signal transmitting method |
| CN102263741B (en) * | 2011-08-22 | 2013-07-24 | 宁波大学 | Method for framing and modulating anti-fading mobile multimedia broadcasting signal of single frequency network |
| CN103780534A (en) * | 2014-01-13 | 2014-05-07 | 宁波大学 | Anti-fading wireless digital broadcasting signal transmission method |
| CN103780533A (en) * | 2014-01-13 | 2014-05-07 | 宁波大学 | Digital broadcasting single frequency network anti-interference mobile signal transmission method |
| CN103763242A (en) * | 2014-01-13 | 2014-04-30 | 宁波大学 | Robust mobile signal transmission method for digital broadcast single frequency network |
| CN103763240A (en) * | 2014-01-13 | 2014-04-30 | 宁波大学 | Anti-fading wireless signal transmission method for digital broadcast |
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| CN101431499A (en) * | 2008-10-27 | 2009-05-13 | 宁波大学 | Space-frequency modulation method for anti-interference digital television ground broadcasting transmitter |
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