CN1173564C - Synchronous time-domain adaptive block transmission method - Google Patents
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Abstract
The present invention relates to a synchronous time domain self-adaptive block transmission method, which belongs to the technical field of signal transmission. The present invention is characterized in that a signal frame is composed of a time domain pilot and a main data block, wherein the main data block is formed by the statistical multiplexing of a plurality of small data blocks which adopt the multi-carrier modulation or the single carrier modulation, and the length of the main data block can be changed; when the data communication is divided into groups, the main data block is divided into M sub blocks (M is more than or equal to 2), the number of the information symbols of each sub block is N<i> (i=1, 2... M, and Ni=N), total N information symbols are transferred, and the receiver uses the self-carried certain head information of the main data block for describing the size, the position and the modulation mode of the sub blocks to carry out the demodulation and the treatment of different communication service for the sub blocks respectively. The present invention can be used for dividing data communication and accessing multi-user to communication; the present invention is particularly suitable for that in the environment of a fast time-varying channel, the influence of the small data blocks in the main data block on the channel can be approximately considered unchanged by regulating the length of the small data blocks, and each sub block adopts the multi-carrier modulation mode or the single carrier modulation mode so as to adapt to different communication requirements.
Description
Technical field
The adaptive block transmission method of Domain Synchronous belongs to the signal transmission technology field, particularly the signal transmission technology field in internet, Digital Television, data broadcasting and the data communication.
Background technology
Through insistent research and development of more than ten years, (Digital TelevisionTerrestrial Broadcasting DTTB) has obtained a lot of achievements to Digital Television Terrestrial Broadcasting, and having reached can implementation phase.From in November, 1998 North America and the Europe DTTB program that started broadcasting, many countries have announced that their DTTB standard selects and realize a plan.At present, mainly contain three kinds of DTTB transmission standards in the world:
1) Advanced Television Systems Committee's (Advanced Television Systems Committee, ATSC) eight level vestigial side bands of Yan Fa lattice code (Trellis-Coded 8-Level Vestigial Side-Band (8-VSB)) modulating system.
The ATSC digital television standard is the ATSC of Advanced Television Systems Committee exploitation.
In May, 1993, the group of a few family of U.S. research digital HDTV forms Major Leagues (GA).Through Advanced Television Test Center (ATTC) Major Leagues' system for field is tested, September nineteen ninety-five, the United States advanced television system committee (ATSC) has submitted the digital television standard report to FCC (FCC), through the congressional hearing debate, on December 26th, 1996, FCC formally announced " digital television standard " ATSC.ATSC has not only comprised high definition TV (HDTV), has also increased standard definition television (SDTV) standard.Video, audio frequency and the auxiliary data of this system high quality in the 6MHz channel can send about 19Mbps total capacity information in a 6MHz terrestrial broadcasting channel, and send about 38Mbps total capacity information in a 6MHz cable TV channel.Compression ratio is 50: 1 or higher.This system is become by three groups of subsystems.That is: source encoding and compression subsystem; Service integration and transmit subsystem and RF transmission subsystem.
2) digital video broadcast-terrestrial (Digital Video Terrestrial Broadcasting-Terrestrial, DVB-T) Coded Orthogonal Frequency Division Multiplexing (COFDM) of standard employing (Coded Orthogonal Frequency Division Multiplexing, COFDM) modulation.
The DVB-T system is the association of European both privately and publicly owned's tissue---digital video broadcasting (DVB) exploitation.
Europe has stopped the digital-to-analogue mixed HD-MAC system of original development and has begun the research of digital television broadcasting DVB in 1993; afterwards, the ETSI of european telecommunication association had successively announced the standard of DVB-S (satellite broadcasting), DVB-C (cable tv broadcast) and DVB-T (terrestrial broadcasting).This series standard is considered the transmission of digital video and audio frequency, and upcoming multimedia programming.Aspect source encoding, DVB standard code digital television system is used unified moving image encoding group-2 (MPEG-2) compression method and mpeg 2 transport stream and multiplexing method; Aspect terrestrial transmission, it adopts COFDM (Coded Orthogonal Frequency Division Multiplexing (COFDM)) modulation technique different with the U.S., and this disturbs for anti-multipath and moves to receive tangible advantage.
3) floor synthetic service digital broadcasting (Integrated Service Digital Broadcasting-Terrestrial, ISDB-T) the frequency band segment transmissions of Cai Yonging (Bandwidth Segmented Transmission, BST) orthogonal frequency division multiplex OFDM.
The ISDB-T system is that (Association of Radio Industries andBusinesses ARIB) develops Japanese association of radio industrie and business.
Japan is the production power of radio and television equipment, grasps many radio and television new and high technologies, and is maintaining the leading position aspect the development of equipment such as HDTV shooting, video recording, demonstration.The high definition TV satellite broadcasting Hivision standard of simulation standard is Japan exploitation and formally broadcasts to the user, is the high definition television broadcasting of early start in the world.Be analog signal form, and be but as transmission medium (bandwidth 24MHz), so do not belong to the full digital television broadcasting of high compression ratio with satellite channel owing to it.As if Japan does not show its trend in advance the exploitation upsurge of world's television broadcasting system total digitalization, make no public appearances a little.Yet in 1996, Japan proposed DTTB (Digital Television Terrestrial Broadcasting) standard-ISDB-T (broadcasting of floor synthetic service digital) of its development suddenly.This scheme is to be advised by the DiBEG of Japan (digital broadcasting expert group), so also claim the DiBEG standard.The modulator approach that system adopts is called frequency band segment transmissions (BST) OFDM, is made up of one group of common fundamental frequency piece that is called the BST section.
Since a plurality of DTTB system had been arranged, many countries and regions were all in the DTTB system of selecting oneself.For politics and consideration economically, China should formulate the digital television standard of oneself according to national conditions.T-DMB (DMB-T) agreement that Tsing-Hua University proposes is exactly under this background, at above-mentioned present three problems that terrestrial digital television system exists in the world, has proposed terrestrial digital television system a kind of novelty, that be fit to China's national situation.Its core physical-layer techniques time-domain synchronization OFDM (TDS-OFDM) technology in T-DMB (DMB-T) agreement that Tsing-Hua University proposes.
We at first introduce the general model of Channel Transmission, and information sequence Info (n) through having the signal that impulse response receives after being the Channel Transmission of h (n) is being
Rec(n)＝Info(n)*h(n)+w(n)
Wherein w (n) is an additive noise, the linear convolution computing of Info (n) * h (n) expression Info (n) and h (n).Owing to there is the impulse response h (n) of transmission channel, the signal that receives through linear convolution spreads generation time and intersymbol interference (ISI).
The technology of effectively eliminating ISI at present has two kinds: time domain equalization and OFDM (OFDM).Time domain equalization generally is to insert a transversal filter (also claiming transversal filter) behind matched filter, and it is made of the delay line of a band tap, and tap is the equal symbol cycle at interval.The time delayed signal of each tap is delivered to an adder circuit output after weighting, its form is identical with finite impulse response filter (FIR), and the signal after the addition is sent to decision circuit through sampling.The weight coefficient of each tap is adjustable, can eliminate ISI by adjusting weight coefficient.The portfolio effect of equalizer is mainly by the decision of tap number and equalization algorithm, and equalization algorithm is commonly used zero forcing algorithm and lowest mean square distortion algorithm etc.Equalizer divides two kinds of presetting system and self-adapting types.Also have noise jamming in actual channel, it can exert an influence to the convergence of equalizer.In order further to improve performance, often adopt decision-feedback formula equalizer in the practical application, the tap coefficient of feedback equalizer is determined by the channel impulse response hangover that forward equalizer caused.Balanced final effect is that the effect (* h (n)) of the channel property taken advantage of among signal y (n)=x (n) * h (the n)+w (n) that will receive eliminates, (n)+w ' (n) to obtain x, wherein w ' is to handle additive noise afterwards through channel and equalization cascade (n), generally uses channel decoding to handle w ' (n) is eliminated.
The Digital Television of the U.S. has adopted DFF exactly, and modulation technique has adopted digital 8-VSB mode.
The equalizer techniques comparative maturity is widely used in the various communications fields, but it has two shortcomings: the one, and complex structure, cost is higher; The 2nd, only relatively good to the short ISI effect of time delay, poor to the ISI effect that time delay is long.At this moment, adopt OFDM (OFDM) technology better.
When the cycle of the time delay of ISI and transmission symbol was in the same order of magnitude, the influence of ISI will become seriously.Therefore, the cycle that prolongs transmission symbol can overcome the influence of ISI effectively, and this is the principle of OFDM elimination ISI just.OFDM by in a large number on frequency equally spaced subcarrier constitute (establish total N carrier wave).The symbol sebolic addressing of serial transmission also is divided into the group that length is N, and every group of N interior symbol sends then together respectively by N subcarrier-modulated.So OFDM essence is a kind of parallel modulation technique.Symbol period is prolonged N doubly, thereby improved resistivity ISI.
But when having ISI in the channel, the orthogonality between the OFDM subcarrier can be destroyed, makes receiver can't correctly extract the modulation symbol on each subcarrier.Need to insert a protection interval delta before the cycle at each ofdm signal when practical application, the actual transmissions cycle of OFDM becomes the Ts=T+ Δ for this reason.Signal in the protection at interval carries out periodic extension by ofdm signal and generates, and is equivalent to the afterbody of ofdm signal catadioptric to the front.When the time delay of ISI is no more than Δ, because ofdm signal is equivalent to make circular convolution with channel impulse response h (n) through behind the channel, after being equivalent to the influence of the frequency response H (k) that passes through channel, each subcarrier Y (k) of ofdm signal has experienced different declines.But the orthogonality between the OFDM subcarrier still can keep, receiver only extracts time-domain signal in the effective OFDM period T to carry out discrete fourier transform and obtains Y (k), again channel is estimated to obtain to make the frequency response H (k) that discrete fourier transform can obtain H (k) or directly obtain channel behind the impulse response h (n) of channel, use Y (k) ÷ H (k) just can eliminate the frequency response H (k) of channel or the in other words influence of the intersymbol interference (ISI) that produced of the impulse response h (n) of channel at last, obtain the signal after the demodulation.
Principle at aforesaid receiver, we find channel estimating ask H (k) and ofdm signal each subcarrier orthogonality maintenance or use someway recovery (keep or the signal that recovers to receive is the ofdm signal of transmitting terminal and the circular convolution of channel impulse response h (n)), be two important steps of the correct demodulation of realization OFDM.In the aforesaid three kinds DTTB transmission standards that existed, first kind of ATSC digital television standard is single-carrier technology, and the OFDM technology has all been adopted in second kind of digital video broadcast-terrestrial (DVB-T) standard and the third floor synthetic service digital broadcasting (ISDB-T).And ISDB-T is different from DVB-T and mainly has been to use very long interweaving and channel coding technology, does not have too big difference.Therefore we mainly discuss the DVB-T technology.
Adopt the OFDM COFDM transmission of coding in the DVB-T system in Europe.One of the implication of " coding " among the Coded Orthogonal Frequency Division Multiplexing (COFDM) COFDM is meant has inserted some " pilot tone " signals at random in the OFDM frequency spectrum, here so-called " pilot tone " is meant the carrier wave of some OFDM like this, they are modulated by the known data of receiver, what they transmitted is not modulating data itself, because it is known that these data receivers are systems, the purpose that pilot tone is set is that system transmits the parameter of some transmitter or the characteristic of test channel by the data on the pilot tone.
The effect of pilot tone in COFDM is very important, and its use comprises: synchronously, channel estimating, transmission mode identification and follow the tracks of phase noise etc.The data of modulated pilots are the pseudo random sequences that generates from a pseudo-random sequence generator of stipulating in advance.
No matter how the position of pilot tone changes, the number that is used to transmit the carrier wave of effective programme information in each COFDM symbol all is constant, is 1512 in the 2k pattern, is 6048 in the 8k pattern.Because the effect of pilot tone in system is important, for guaranteeing the reliability of data on the pilot tone, prevent noise jamming, the average power of pilot signal is bigger 16/9 times than the average power of other carrier signal, and promptly pilot signal is launched on " lifting " power level.
Just because of OFDM has above-mentioned characteristic, so it has following major advantage: (1) opposing multipath disturbs; (2) support to move reception; (3) can form single frequency network SFN or the like.
But because FFT and pilot tone are mutual demands in COFDM, in the receiver, the pilot tone that receives obtains after FFT handles, and FFT calculates and need at first synchronously (by pilot tone assistance), could calculate FFT then.Therefore, COFDM adopts the iterative approach algorithm, so just has a convergence error and convergence time problem.Therefore just can obtain after in COFDM, needing iterative computation repeatedly synchronously, and when using pilot tone to carry out channel estimating, the value interpolation of need on frequency domain, counting, the estimation of the channel frequency response that interpolation obtains has been compared error with the channel frequency response of reality, and the time span of working as channel impulse response h (n) is big more, be the frequency domain resolution of channel frequency response when high more, this error will be big more.
In time-domain synchronization OFDM modulation (TDS-OFDM), the pilot tone in OFDM (OFDM) signal has been cancelled, and adopts the time domain pilot conduct before the ofdm signal frame synchronous, and channel estimating.Adopt the TDS-OFDM technology to realize need not the synchronous fast of iterative processing by time domain pilot.Time-domain synchronization OFDM modulation (TDS-OFDM) is disclosed patent application, and its name is called " time-domain synchronous orthogonal frequency division multiplex modulation method ", and application number is 01115520.5, and publication number is CN 1317903A.And, adopt the TDS-OFDM technology can by time domain pilot replace among traditional OFDM protection at interval.Use pseudorandom PN sequence to replace protecting among the OFDM at interval and being used for time synchronized; Frequency Synchronization and channel estimating also are disclosed patent applications; it is 01124144.6 that its name is called " protection fill method at interval in the orthogonal FDM modulation system " application number, and publication number is CN 1334655A.
In addition, because the frame of time-domain synchronization OFDM modulation (TDS-OFDM) is made of anti-discrete fourier transform (IDFT) data block of one a section time domain pilot and an OFDM (OFDM), the channel estimation results that TDS-OFDM method hypothesis uses time domain pilot to obtain is constant or change very little in the time range of the IDFT data block of an OFDM who is right after time domain pilot.The channel estimating that obtains with time domain pilot just can be used to offset the influence of the suffered channel of this data block like this.This require when static state constant channel and the time to become slowly in the channel be satisfiable, but then can not satisfy for the fast time variant channel.What mobile communication was faced is exactly a kind of typical fast time variant channel, because mobile phone, vehicle-mounted receiver, Deng moving on the space of mobile receiving device, make signal transduction pathway between the transmitter and receiver, just the wireless transmission channel between them all is being in the middle of the continuous variation all the time, and this pace of change is relevant with the movement velocity of mobile receiving device.Under the situation of high-speed motion, channel has often experienced violent variation in the time range of a data block, and the channel estimating that causes TDS-OFDM to use time domain pilot to obtain can not reflect the influence of the channel of the actual experience of data.To produce very big error code through incorrect compensation like this.
In addition in multi-user's access communications, divide in the communication mode of multiple access in present direct sequence spread spectrum codes, transmit on the different time slots of each user's signal in the regular hour interval, signal on these different time slots is not necessarily identical with user's signal, but definite relation is arranged.Definite relation of the signal on the different time-gap in each user's the signal time interval certain with it is different.In multi-user communication, the signal of different user is superimposed upon in this time interval, each user is when its information of extraction, by the relation of determining of user's signal therewith of the signal on its known time slot different in this time interval, pass through related operation, overcome the interference of other user profile, and strengthen the signal of oneself, information is extracted.In the communication mode of present MC-CDMA, transmit on the different subcarrier in frequency domain of each user's signal in the regular hour interval, signal on these different subcarrier in frequency domain is not necessarily identical with user's signal, but definite relation is arranged.Definite relation of the signal on the different time-gap in each user's the signal time interval certain with it is different.In multi-user communication, each user by related operation, overcomes the interference of other user profile by definite relation of the signal on own signal and the different subcarrier in frequency domain, and the signal of enhancing oneself, and information is extracted.But divide in the communication mode of multiple access and MC-CDMA in direct sequence spread spectrum codes, this related operation all is to carry out in a big data block, as mentioned above, channel has often experienced violent variation in the time range of this big data block, thereby cause such related operation can not well overcome the interference of other user profile, and the signal of enhancing oneself, information is extracted.
Summary of the invention
The objective of the invention is to be to provide a kind of adaptive block transmission method that can be used for the Domain Synchronous of multiple different communication mode, it both can be used for block data communication and also can be used for multi-user's access communications business; Adaptive block transmission method in Domain Synchronous of the present invention is that information symbol to be transmitted at first is divided into M sub-piece, each sub-piece is adopted multi-carrier modulation or single-carrier modulated respectively, like this when transmitting in the channel of signal at fast time variant, though variation has taken place in channel characteristics in the big time range of whole data block, this a little hour between can think that channel characteristics does not change or changes very little in the scope.The length that we can divide each sub-piece according to the speed degree that channel characteristics changes satisfies this hypothesis, and this is the adaptation to channel.Each sub-piece can be thought the influence of having experienced the constant channel of feature like this, is convenient to receiver signal is recovered out.
In addition, in the adaptive block transmission method of Domain Synchronous of the present invention, be with the method for plurality of sub piece by the statistic multiplexing of time-division, with its synthetic total data block, and use header will be contained in the size of the sub-piece in total data block in total data block, the position, modulation coding mode is noted down, and reads and the recognin piece for receiver.If the length requirement of total data block is certain, when sub-piece statistic multiplexing, if total data block also has certain space and sub-piece of not enough insertion, can be suitable in these spaces, insert some fixed signals, data block is filled into the length of design, then total data block and time domain pilot are synthesized signal frame, send.If the length of total data block does not require necessarily, to certain length, just can constitute signal frame at sub-piece statistic multiplexing with time domain pilot, send.The length of at this moment total data block is not certain, receiver by time domain pilot known in to the received signal synchronously, separate known time domain pilot then, just remaining total data block signal, according to the size of its contained sub-piece of record in total data block, certain header of position and modulation system divides the processing of other demodulation and different communication business to each sub-piece again.If transmitter and receiver has been arranged the internal structure of total data piece in advance, this header can omit.Can adapt to the different communication business flexibly like this.
In OFDM (OFDM), N signal is placed on the transmission that walks abreast on the subcarrier of quadrature on N the frequency domain, they are superimposed on time domain, the peak-to-average power of this ofdm signal piece time-domain signal is bigger, in realization to the performance requirement of linear amplification device than higher, power consumption is also bigger, and N is big more, and the peak-to-average power ratio of block will be big more.The adaptive block transmission method of Domain Synchronous of the present invention is that this N information symbol to be transmitted at first is divided into M sub-piece, the M here 〉=2, and the information symbol quantity of each sub-piece is N
i, i=1 wherein, 2....M represents the sequence number of sub-piece.M and N
iSatisfy
Be total N information symbol that still transmit.The needs that in the individual sub-piece of this M each is looked application can use multi-carrier modulation also can use single-carrier modulated.Like this through dividing after the sub-piece, because this a little when carrying out multi-carrier modulation, the sub-carrier number of sub-piece is respectively N
i, N is arranged
i＜N, i=1 wherein, 2....M compares with a whole N information symbol is done multi-carrier modulation, and the peak-to-average power of sub-piece is lower, makes the peak-to-average power of whole data block than reducing, and has reduced the performance requirement to system's neutral line amplifying device.
In the adaptive block transmission method of Domain Synchronous of the present invention, total data block can be used to transmit the multi-user and insert signal.Because total data block can be made of the sub-piece of some multicarriers that do not overlap on the time and single-carrier modulated, transmit on the different time slot that each user's signal can be in the regular hour interval and the different subcarrier in frequency domain like this, on these different time slots, signal on the different subcarrier in frequency domain is not necessarily identical with user's signal, but definite relation is arranged.On the different time slot in each user's signal and its certain time interval, definite relation of the signal on the different subcarrier in frequency domain is different.The advantage of the adaptive block transmission method of similar Domain Synchronous above-mentioned in the transmission of piece time varying channel, size by the suitable sub-piece of design, what can be similar to thinks that the feature of the channel in a sub-piece is constant, like this can be in multi-user communication, on time slots different in each user signal and its certain time interval by oneself, definite relation of the signal on the different subcarrier in frequency domain, better pass through related operation, overcome the interference of other user profile, and the signal of enhancing oneself, information is extracted.
The communication mode of present MC-CDMA is different with the multiple-user access method of the adaptive block transmission method of Domain Synchronous of the present invention, the frame of the communication mode of MC-CDMA is to be made of an OFDM piece and its Cyclic Prefix, and the frame of the adaptive block transmission method of Domain Synchronous of the present invention all is to be made of a total data block and one section time domain pilot.The difference of the two is 3 points, and the time domain pilot of frame has replaced the Cyclic Prefix of the frame in the communication mode of MC-CDMA in the adaptive block transmission method of one, Domain Synchronous of the present invention; Two, total data block of frame is made of the plurality of sub piece in the adaptive block transmission method of Domain Synchronous of the present invention, each sub-piece can adopt multi-carrier modulation also can adopt single-carrier modulated respectively, and the OFDM piece of the frame in the communication mode of MC-CDMA is exactly a multi-carrier modulation piece; Three, in the adaptive block transmission method of Domain Synchronous of the present invention, on the different time slot in the sub-piece of a plurality of single-carrier modulated that each user's signal can not overlap on the time in total data block simultaneously or transmit on the different subcarrier in frequency domain in the sub-piece of a plurality of multi-carrier modulation, and in the communication mode of MC-CDMA, each user's signal is exactly to transmit on the different subcarrier in frequency domain in the data block of an OFDM multi-carrier modulation simultaneously.
The invention is characterized in: it contains following steps successively:
(1) the single communication service that will transmit or the data flow of a plurality of communication services are packaged as some little data blocks earlier;
(2) carry out single-carrier modulated or multi-carrier modulation respectively according to the needs data block that these are little of concrete communication service, obtain the small data piece through ovennodulation, described multi-carrier modulation adopts the OFDM method;
(3) will be multiplexed with a total data block through the small data piece of ovennodulation;
(4) in total data block, insert be used to write down through ovennodulation and multiplexing after the header of size, position and modulation system of small data piece;
(5) time domain pilot and the described total data chunk of step (4) are combined into signal frame;
(6) transmitter is divided into M sub-piece to total data block when block data communication, M 〉=2, and the information symbol quantity of each sub-piece is N
i, i=1,2....M, i represent the sequence number of sub-piece, a total transmission N information symbol,
(7) receiver is used to describe the wherein size of contained sub-piece by what total data block oneself was carried, the certain header of the form of position and modulation system is separated the processing of mediation different communication business respectively to each sub-piece: when inserting signal with total data block transmission multi-user, total data block is that the sub-piece by some multicarriers that do not overlap on the time and/or single-carrier modulated constitutes, each user's signal is simultaneously on the different time slot in the sub-piece of single-carrier modulated and/or transmit on the different subcarrier in frequency domain in the sub-piece of multi-carrier modulation, but these of each user are simultaneously on the different time slots in the sub-piece of single-carrier modulated and/or the signal that transmits on the different subcarrier in frequency domain in the sub-piece of multi-carrier modulation and each user signal that will transmit itself is not necessarily identical has definite relation; And the signal and those that itself will transmit different user its simultaneously on the different time slot in the sub-piece of single-carrier modulated and/or the definite relation that signal had that transmits on the different subcarrier in frequency domain in the sub-piece of multi-carrier modulation be different; In multi-user communication, each user by oneself signal with its simultaneously on the different time slot in the sub-piece of single-carrier modulated and/or the relation of determining of the signal that transmits on the different subcarrier in frequency domain in the sub-piece of multi-carrier modulation, pass through related operation, overcome the interference of other user profile, and the signal of enhancing oneself, information is extracted.
The adaptive block transmission method of above-mentioned Domain Synchronous is characterized in that, the form of described header is arranged in transmitter and receiver in advance.
Characteristics of the present invention and effect:
The adaptive block transmission method of Domain Synchronous of the present invention, it is the improvement project of the Design of Signal of the digital television transfer scheme that proposes of Tsing-Hua University, in the digital television transfer scheme that Tsing-Hua University proposes, important use is arranged, experimental results show that it can realize intended purposes.
Description of drawings
One of Fig. 1 signal frame structure figure.
Two of Fig. 2 signal frame structure figure.
Fig. 3 signal frame forms schematic diagram.
Embodiment
In the adaptive block transmission method of Domain Synchronous of the present invention, be with the method for plurality of sub piece by the statistic multiplexing of time-division, with its synthetic total data block, and use header will be contained in the size of the sub-piece in total data block in total data block, the position, modulation coding mode is noted down, and reads and the recognin piece for receiver.If the length requirement of total data block is certain, when sub-piece statistic multiplexing, if total data block also has certain space and sub-piece of not enough insertion, can be suitable in these spaces, insert some fixed signals, data block is filled into the length of design, then total data block and time domain pilot are synthesized signal frame, send.If the length of total data block does not require necessarily, to certain length, just can constitute signal frame at sub-piece statistic multiplexing with time domain pilot, send.The length of at this moment total data block is not certain.If transmitter and receiver has been arranged the internal structure of total data block in advance, then can not transmit header, signal frame structure as shown in Figure 1 at this moment, if total data block contains header, this moment signal frame structure as shown in Figure 2, the optional position that header can be arranged in total data block.
The signal frame of the adaptive block transmission method of Domain Synchronous forms and follows these steps to carry out:
1. the single communication service that will transmit or the data flow of a plurality of communication services are packaged as some little data blocks earlier;
2. carry out single-carrier modulated or multi-carrier modulation respectively according to the needs of the concrete communication service data block that these are little and obtain small data piece through ovennodulation, multi-carrier modulation adopts the IDFT computing to carry out;
3. will be multiplexed with a total data block through the small data piece of ovennodulation;
4. in total data block, insert be used to note down through ovennodulation and multiplexing after the header of size, position and modulation system of small data piece;
5. time domain pilot and total data chunk are combined into signal frame;
Above step as shown in Figure 3.
The adaptive block transmission method of Domain Synchronous of the present invention also goes for the personal communication field, and a kind of multi-user's access communications mode is provided.As Fig. 1, Fig. 2 and shown in Figure 3, because total data block can be made of the sub-piece of some multicarriers that do not overlap on the time and/or single-carrier modulated, each user's signal is simultaneously on the different time slot in the sub-piece of single-carrier modulated and/or transmit on the different subcarrier in frequency domain in the sub-piece of multi-carrier modulation, but these of each user are simultaneously on the different time slots in the sub-piece of single-carrier modulated and/or the signal that transmits on the different subcarrier in frequency domain in the sub-piece of multi-carrier modulation and each user signal that will transmit itself is not necessarily identical has definite relation; And the signal and those that itself will transmit different user its simultaneously on the different time slot in the sub-piece of single-carrier modulated and/or the definite relation that signal had that transmits on the different subcarrier in frequency domain in the sub-piece of multi-carrier modulation be different.
Claims (2)
1, the adaptive block transmission method of Domain Synchronous is characterized in that, it contains following steps successively:
(1) the single communication service that will transmit or the data flow of a plurality of communication services are packaged as some little data blocks earlier;
(2) carry out single-carrier modulated or multi-carrier modulation respectively according to the needs data block that these are little of concrete communication service, obtain the small data piece through ovennodulation, described multi-carrier modulation adopts the OFDM method;
(3) will be multiplexed with a total data block through the small data piece of ovennodulation;
(4) in total data block, insert be used to write down through ovennodulation and multiplexing after the header of size, position and modulation system of small data piece;
(5) time domain pilot and the described total data chunk of step (4) are combined into signal frame;
(6) transmitter is divided into M sub-piece to total data block when block data communication, M 〉=2, and the information symbol quantity of each sub-piece is N
i, i=1,2....M, i represent the sequence number of sub-piece, a total transmission N information symbol,
(7) receiver is used to describe the wherein size of contained sub-piece by what total data block oneself was carried, the certain header of the form of position and modulation system is separated the processing of mediation different communication business respectively to each sub-piece: when inserting signal with total data block transmission multi-user, total data block is that the sub-piece by some multicarriers that do not overlap on the time and/or single-carrier modulated constitutes, each user's signal is simultaneously on the different time slot in the sub-piece of single-carrier modulated and/or transmit on the different subcarrier in frequency domain in the sub-piece of multi-carrier modulation, but these of each user are simultaneously on the different time slots in the sub-piece of single-carrier modulated and/or the signal that transmits on the different subcarrier in frequency domain in the sub-piece of multi-carrier modulation and each user signal that will transmit itself is not necessarily identical has definite relation; And the signal and those that itself will transmit different user its simultaneously on the different time slot in the sub-piece of single-carrier modulated and/or the definite relation that signal had that transmits on the different subcarrier in frequency domain in the sub-piece of multi-carrier modulation be different; In multi-user communication, each user by oneself signal with its simultaneously on the different time slot in the sub-piece of single-carrier modulated and/or the relation of determining of the signal that transmits on the different subcarrier in frequency domain in the sub-piece of multi-carrier modulation, pass through related operation, overcome the interference of other user profile, and the signal of enhancing oneself, information is extracted.
2, the adaptive block transmission method of Domain Synchronous according to claim 1 is characterized in that: the form of described header is arranged in transmitter and receiver in advance.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB021313385A CN1173564C (en) | 2002-09-29 | 2002-09-29 | Synchronous time-domain adaptive block transmission method |
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| CNB021313385A CN1173564C (en) | 2002-09-29 | 2002-09-29 | Synchronous time-domain adaptive block transmission method |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101588463B (en) * | 2004-12-17 | 2012-12-12 | 三星电子株式会社 | Digital multimedia receiver and a digital multimedia receiving method thereof |
| CN101489056B (en) * | 2004-12-17 | 2011-02-16 | 三星电子株式会社 | Digital multimedia signal receiver and channel pre-searching method thereof |
| TWI332784B (en) * | 2005-09-22 | 2010-11-01 | Qualcomm Inc | Pilot grouping and route protocols in multi-carrier communication systems |
| KR20070113349A (en) * | 2006-05-23 | 2007-11-29 | 엘지전자 주식회사 | Apparatus for demodulating broadcasting signal and method for transmitting and receiving broadcasting signal |
| KR20070113350A (en) * | 2006-05-23 | 2007-11-29 | 엘지전자 주식회사 | Apparatus for transmitting a broadcasting signal and method thereof |
| CN1913396B (en) * | 2006-09-12 | 2011-10-05 | 北京邮电大学 | Single/multiple carrier compatible digital broadcast system communication method |
| WO2012016353A1 (en) * | 2010-08-04 | 2012-02-09 | Nec (China) Co., Ltd. | Signal for transmission in single-carrier communication system |
| CN116545813B (en) * | 2023-06-28 | 2023-09-01 | 山东云海国创云计算装备产业创新中心有限公司 | Server, communication equipment, communication chip and forward equalization circuit |
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