CN105743624A - Generation method for preamble symbol and receiving method - Google Patents

Abstract

The invention provides a generation method for a preamble symbol and a receiving method. The method comprises: on the basis of an obtained time-domain main body signal, a time domain symbol having any one of two three-segment structures; and a preamble symbol is generated based on one or two time domain symbols. The two three-segment structures are as follows: one three-segment structure is formed by a main body, a prefix generated based on the rear part of the main body, and a postfix generated and modulated based on the rear part of the main body; and the other three-segment structure is formed by a main body, a prefix generated based on rear part of the main body, and a super prefix generated and modulated based on the rear part of the main body. A common preamble symbol is generated based on one time domain symbol; and a reinforced preamble symbol is generated in a splicing mode based on two time domain symbols having the different three-segment structures. Besides, the receiving method of a receiving terminal includes: a physical frame is processed to obtain a baseband signal; whether an expected common or reinforced preamble symbol exists in the baseband signal is determined; and if so, the position of the preamble symbol in the physical frame is determined and carried signaling information is solved.

Description

The generation method of leading symbol and method of reseptance

Technical field

The present invention relates to wireless broadcast communication technical field, particularly to generation method and the method for reseptance of a kind of leading symbol.

Background technology

Correctly demodulating, generally for the receiving terminal making ofdm system, the data that transmitting terminal sends, ofdm system must realize between transmitting terminal and receiving terminal time synchronized accurately and reliably.Simultaneously as ofdm system is very sensitive to the frequency deviation of carrier wave, the receiving terminal of ofdm system it is also required to provide the carrier spectrum method of estimation of precise and high efficiency, to carry out carrier wave frequency deviation estimating accurately and correcting.

At present, ofdm system realizes method that transmitting terminal and destination time synchronize be substantially and realize based on leading symbol.Leading symbol is the transmitting terminal of ofdm system and all known symbol sebolic addressing of receiving terminal, the leading symbol mark beginning of physical frame (called after P1 symbol), only occurring a P1 symbol in each physical frame or occur multiple P1 symbols continuously, the purposes of P1 symbol includes:

1) receiving terminal is made to detect rapidly to determine the signal whether received of transmission in channel for expectation；

2) provide and substantially transmit parameter (such as FFT count, frame type information etc.), make receiving terminal can carry out receipt of subsequent process；

3) original carrier frequency deviation and timing error are detected, in order to reach frequency and Timing Synchronization after compensating；

4) emergency alarm or broadcast system wake up.

DVB_T2 standard proposes the P1 Design of Symbols based on CAB spatial structure, achieves above-mentioned functions preferably.But, low complex degree receiving algorithm still has some limit to.Such as, when the long multipath channel of 1024,542 or 482 symbols, utilize the such three-stage structure of CAB to be timed thick synchronization and relatively large deviation can occur, cause frequency domain being estimated, mistake occurs in carrier wave integer frequency offset.It addition, when complex frequency Selective Fading Channel, for instance during long multipath, DBPSK differential decoding is likely to and can lose efficacy.It is additionally, since in DVB_T2 spatial structure and there is no Cyclic Prefix, and if needing to carry out the frequency-domain structure combination of channel estimating, the problem that will result in its channel estimation in frequency domain performance degradation.

Summary of the invention

The problem that this invention address that is in current DVB_T2 standard and other standards, the problem that not this invention address that in DVB_T2 spatial structure is in current DVB_T2 standard and other standards, DVB_T2 spatial structure do not have Cyclic Prefix, it is not applied for relevant detection, and leading symbol low complex degree receiving algorithm under complex frequency Selective Fading Channel detects problem probability of failure occur.

For solving the problems referred to above, embodiments provide a kind of generation method of leading symbol, it is characterised in that comprise the steps: to generate the time-domain symbol of any one three-stage structure having in following two kinds based on obtained time domain main running signal；And generate leading symbol based on one or two time-domain symbol, wherein, the first three-stage structure is: time domain main running signal, based on the prefix that the rear portion of this time domain main running signal generates, and the suffix of the modulated generation in rear portion based on this time domain main running signal, the second three-stage structure is: time domain main running signal, based on the prefix that the rear portion of this time domain main running signal generates, and the sewing in advance of the modulated generation in rear portion based on this time domain main running signal, common leading symbol is generated when based on a time-domain symbol, when having the time-domain symbol of different three-stage structure based on two, splicing generates and strengthens leading symbol.

Alternatively, time domain main running signal is that the frequency-domain OFDM symbol to predetermined length carries out inverse discrete Fourier transform and changes and the time-domain OFDM symbol that obtains.

Alternatively, frequency-domain OFDM symbol includes virtual subnet carrier wave, signaling sequence subcarrier and fixed sequence program subcarrier, after signaling sequence subcarrier and fixed sequence program subcarrier are arranged according to the predetermined rule that is staggered, by virtual subnet distribution of carriers in its both sides, the predetermined rule that is staggered comprises any one in following two rule: the first predetermined rule that is staggered: in oem character set or even strange staggered arrange；And the second predetermined rule that is staggered: a part of signaling sequence is placed on odd subcarriers, and another part signaling sequence is placed on even subcarriers, and a part of fixed sequence program is placed on odd subcarriers, and another part fixed sequence program is placed on even subcarriers.

Alternatively, in prefix, in suffix or the generation step sewed in advance, comprise the steps of time domain main running signal as Part I, the least significant end of neat Part I takes out a part according to the predetermined rule that obtains, the front portion processing and copying to this Part I is carried out to generate Part III thus as prefix according to the first predetermined process rule, simultaneously, a part is taken out from the rear portion of Part I according to the predetermined rule that obtains, carry out processing and copy to the rear portion of this Part I or process according to the second predetermined process rule and copy to the front portion of prefix to generate Part II thus corresponding as suffix or sew in advance respectively.

Alternatively, wherein, the predetermined rule that obtains includes: set Len_BFor the length of Part II, Len_CFor the length of Part III, Len_B≤Len_C, separately setting N1 as selecting to be copied to the sampled point sequence number of Part I corresponding to the starting point of Part II, N2 is the sampled point sequence number of the Part I that the terminal selecting to be copied to Part II is corresponding, then meet below equation: N2=N1+Len_B-1。

Alternatively, wherein, the first predetermined process rule includes: direct copying；Or to each sampled signal in taking-up part be multiplied by an identical fixed coefficient or predetermined different coefficient, the second predetermined process rule includes: be modulated when the first predetermined process rule is direct copying processing；Or when the first predetermined process rule be each sampled signal in institute's taking-up part be multiplied by an identical fixed coefficient or predetermined different coefficient time be also multiplied by corresponding coefficient after carry out modulation treatment.

Alternatively, wherein, common leading symbol is based on same time domain main running signal, by any one in the first three-stage structure and the second three-stage structure for identifying emergent broadcast.

Alternatively, wherein, strengthen in two different time domain symbols of leading symbol, two time domain main running signal is different, and the three-stage structure of employing is also different, form the first respectively by the different successively sequences of two time-domain symbol and strengthen leading symbol and the second reinforcement leading symbol, broadcast for identifying emergent.

The embodiment of the present invention additionally provides the method for reseptance of a kind of leading symbol, it is characterised in that comprise the steps: step S2-1: process to obtain baseband signal to the physical frame received；Step S2-2: judge the common leading symbol whether existing in the claim 1 that expectation receives in baseband signal or strengthen leading symbol；Step S2-3: when being judged as YES, it is determined that this leading symbol position in physical frame also solves the signaling information entrained by this leading symbol.

Alternatively, physical frame is processed to be comprised the steps: when the signal received is for zero intermediate frequency signals obtaining baseband signal, after analog digital conversion, filter, down-sampling processes and obtains baseband signal again, when the signal received is intermediate-freuqncy signal, frequency spectrum shift after analog digital conversion, then filter, down-sampling process obtain baseband signal.

Alternatively, in the common leading symbol situation of the only possible transmission of known transmitting terminal, judge whether baseband signal exists the common leading symbol that expectation receives and comprise the steps: step S2-21A: obtain rule and/or predetermined process rule according to the Part III in the common leading symbol that the expectation in such as claim 7 receives, Part I and Part II between any two predetermined, carry out postponing slip auto-correlation after baseband signal carries out correspondingly inverse processing and signal demodulation, to obtain three relevant accumulated values of delay；Step S2-21B: at least one delay in relevant accumulated value based on these three performs mathematical calculations, and this mathematical operation result is carried out peakvalue's checking；And step S2-21C: if the result of peakvalue's checking meets pre-conditioned, it is determined that baseband signal exists the common targeting signal that expectation receives.

Alternatively, when leading symbol is strengthened in the only possible transmission of known transmitting terminal, judge that the reinforcement leading symbol that whether there is expectation reception in baseband signal comprises the steps: step S2-22A: strengthen the Part III of the first three-stage structure and the second three-stage structure in leading symbol according to what expectation received, the predetermined acquisition between any two of Part I and Part II is regular and/or predetermined process is regular, carry out postponing slip auto-correlation after baseband signal carries out correspondingly inverse processing and signal demodulation, to obtain six relevant accumulated values of delay, these six values are actual in 3 delay correlators acquisitions, wherein, when strengthening the fixed sequence program of two symbols of leading symbol and adopting identical, also can obtain the relevant accumulated value of delay of the Part III of former and later two symbols and the combined and spliced part of Part I；Step S2-22B: the carrying out that the six of step S2-22A relevant accumulated values of delay have same delay relation is added or is added after phase place adjustment, obtain three different relevant accumulated values postponed, postpone relevant accumulated value based on these three to perform mathematical calculations with at least one in the relevant accumulated value of delay of the combined and spliced part of the Part III of former and later two symbols and Part I, and this mathematical operation result is carried out peakvalue's checking；Step S2-22C: if the result of peakvalue's checking meets pre-conditioned, it is determined that there is the reinforcement targeting signal that expectation receives in baseband signal.

Alternatively, determine that this leading symbol position in physical frame includes: determine this leading symbol position in physical frame based on the result meeting pre-conditioned peakvalue's checking, if there is the leading symbol that expectation receives, the residing partial value big according to peak value or maximum are determined position that leading symbol occurs in physical frame or carry out fractional part of frequency offset estimation.

Alternatively, utilize the frequency-region signal that all or part of time domain waveform of leading symbol and/or all or part of time domain waveform of this leading symbol obtain after Fourier transformation, comprise the steps: that the time-domain signal by the signal comprising signaling sequence subcarrier is corresponding with signaling sequence t easet ofasubcarriers or this signaling sequence t easet ofasubcarriers carries out computing with the signaling information solved entrained by this leading symbol, to solve in this leading symbol the signaling information entrained by signaling sequence subcarrier, wherein signaling sequence t easet ofasubcarriers produces based on known signaling sequence set.

Alternatively, the method for reseptance of the leading symbol in the embodiment of the present invention, it is characterised in that also comprise the steps: 1) according to being determined this leading symbol position in physical frame, intercept the signal comprising stator carrier wave；2) time-domain signal that this signal comprising stator carrier wave is corresponding with frequency domain stator carrier wave sequence or this frequency domain stator carrier wave sequence is carried out computing, to obtain integer frequency offset estimation or channel estimating.

Compared with prior art, technical solution of the present invention has the advantages that

The generation method of the leading symbol provided according to embodiments of the present invention is with method of reseptance, the signal of certain length is intercepted as Cyclic Prefix or when sewing in advance from the rear portion of time domain main running signal, relevant detection can be realized, the problem solving noncoherent detection hydraulic performance decline, and the signal based on the circulating prefix-length of above-mentioned intercepting generates modulation signal, make the leading symbol generated have good fractional part of frequency offset and estimate performance and Timing Synchronization performance, further, one or two symbols of transmission can be selected respectively as common leading symbol or to strengthen leading symbol according to the requirement of efficiency of transmission and robustness, when the symbol of one three-stage structure of transmission is as leading symbol, based on same OFDM symbol main body, by designing three-stage structure two kinds different, carry out identifying emergent broadcast；nullWhen the symbol of two three-stage structures of transmission is as leading symbol，Two OFDM symbol main body is different，And the three-stage structure adopted is also just different，On this basis，Arrange identifying emergent broadcast by the sequencing of two three-stage structures，By the three-stage structure that two symbols are different，The little inclined problem estimating to lose efficacy occurred under some particular length multipath channel can be avoided，Further，The leading symbol of the present invention utilizes three sections of structures with part identical content，Ensure that to utilize at receiving terminal and postpone the relevant peak value that may be significantly，And，In generating this leading symbol process，The modulation signal of design time domain main body number can avoid receiving terminal to be subject to continuous wave CO_2 laser or mono-tone interference，Or occur and modulate the multipath channel that signal length is isometric，Or reception signal is protected gap length, time identical with modulation signal length, the such situation of error detection peak value occurs.

Accompanying drawing explanation

Fig. 1 is the schematic flow sheet of the embodiment of the generation method of the leading symbol of the present invention；

Fig. 2 is the schematic diagram of three-stage structure in the first common leading symbol in embodiments of the invention；

Fig. 3 is the schematic diagram of three-stage structure in the common leading symbol of the second in embodiments of the invention；

Fig. 4 is the schematic diagram processed based on the first common leading symbol acquisition in embodiments of the invention；

Fig. 5 is the schematic diagram processed based on the common leading symbol acquisition of the second in embodiments of the invention；

Fig. 6 is that in embodiments of the invention, the first strengthens the schematic diagram of two three-stage structures in leading symbol；

Fig. 7 is that in embodiments of the invention, the second strengthens the schematic diagram of two three-stage structures in leading symbol；

Fig. 8 strengthens, based on the first, the schematic diagram that leading symbol acquisition processes in embodiments of the invention；

Fig. 9 strengthens, based on the second, the schematic diagram that leading symbol acquisition processes in embodiments of the invention；

Figure 10 is signaling sequence subcarrier in embodiments of the invention, fixed sequence program subcarrier and the virtual subnet carrier wave arrangement schematic diagram according to the first predetermined rule that is staggered；

Figure 11 is signaling sequence subcarrier in embodiments of the invention, fixed sequence program subcarrier and the virtual subnet carrier wave arrangement schematic diagram according to the second predetermined rule that is staggered；

Figure 12 is the arrangement schematic diagram that in embodiments of the invention, two the time domain main running signals strengthened in leading symbol carry out relative integral shift with the shift value 1 in predetermined association rule；

Figure 13 is the arrangement schematic diagram that in embodiments of the invention, two the time domain main running signals strengthened in leading symbol carry out relative integral shift with the shift value 2 in predetermined association rule；

Figure 14 is the schematic flow sheet of the detailed description of the invention of the method for reseptance of the leading symbol of the present invention；

Figure 15 be in embodiments of the invention corresponding to three-stage structure CAB the first common leading symbol peak value obtain logical schematic；

Figure 16 be in embodiments of the invention corresponding to three-stage structure BCA the common leading symbol of the second peak value obtain logical schematic；

Figure 17 be in embodiments of the invention the first strengthen leading symbol peak value obtain logical schematic；And

Figure 18 be in embodiments of the invention the second strengthen leading symbol peak value obtain logical schematic.

Detailed description of the invention

Inventor have found that in current DVB_T2 standard and other standards, DVB_T2 spatial structure do not have Cyclic Prefix, it is not applied for relevant detection, and leading symbol low complex degree receiving algorithm under complex frequency Selective Fading Channel detects problem probability of failure occur.

For the problems referred to above, inventor is through research, provide generation method and the method for reseptance of a kind of leading symbol, the problem solving noncoherent detection hydraulic performance decline, there is good fractional part of frequency offset and estimate performance and Timing Synchronization performance, the little inclined problem estimating to lose efficacy that also can avoid occurring under some particular length multipath channel, it is ensured that utilize at receiving terminal and postpone the relevant peak value that may be significantly, it is to avoid the situation of the above-mentioned error detection peak value of appearance.

Understandable in order to enable the above-mentioned purpose of the present invention, feature and advantage to become apparent from, below in conjunction with accompanying drawing, the specific embodiment of the present invention is described in detail.

Fig. 1 is the schematic flow sheet of the embodiment of the generation method of the leading symbol of the present invention.As it is shown in figure 1, the generation method of leading symbol comprises the steps: in the present embodiment

Step S1-1: obtain time domain main running signal；

Step S1-2: generate the time-domain symbol of any one three-stage structure having in the first three-stage structure and the second three-stage structure based on obtained time domain main running signal；And

Step S1-3: generate leading symbol based on one or two time-domain symbol,

Wherein, the first three-stage structure is: the suffix of the prefix that time domain main running signal, rear portion based on this time domain main running signal generate and the modulated generation in rear portion based on this time domain main running signal, and the second three-stage structure is: prefix that time domain main running signal, rear portion based on this time domain main running signal generate and the sewing in advance of the modulated generation in rear portion based on this time domain main running signal.

When generating leading symbol when based on a time-domain symbol, this leading symbol is common leading symbol；When based on the time-domain symbol of two different three-stage structures, splicing generates leading symbol, this leading symbol is for strengthening leading symbol.

Fig. 2 is the schematic diagram of three-stage structure in the first common leading symbol in embodiments of the invention.Fig. 3 is the schematic diagram of three-stage structure in the common leading symbol of the second in embodiments of the invention.

By one section of time domain main running signal (in figure using A indicate) as Part I, the least significant end of neat Part I takes out a part according to the predetermined rule that obtains, the front portion processing and copying to this Part I is carried out to generate Part III (in figure using C indicate) thus as prefix according to the first predetermined process rule, simultaneously, a part is taken out from the rear portion of Part I according to the predetermined rule that obtains, carry out processing and copy to the rear portion of this Part I or process according to the second predetermined process rule and copy to the front portion of prefix to generate Part II (indicating using B in figure) thus corresponding as suffix or sew in advance respectively, thus, generate B as shown in Figure 2 respectively as the first common leading symbol (CAB structure) of suffix and B as the common leading symbol of the second as shown in Figure 3 (BCA structure) sewed in advance.

In the present embodiment, when sending the first common leading symbol, represent that system is sending general broadcast service；When the common leading symbol of transmission the second, represent that system is sending emergent broadcast service.The present invention can also be, when sending the first common leading symbol, represents that system is sending emergent broadcast service, and when sending the common leading symbol of the second, represents that system is sending general broadcast service.Common leading symbol is based on same time domain main running signal, by any one in the first three-stage structure (CAB structure) and the second three-stage structure (BCA structure) for identifying emergent broadcast.

About carrying out after obtaining out Part III, Part II from Part I processing specific rules, the first predetermined process rule includes: direct copying；Or to each sampled signal in taking-up part be multiplied by an identical fixed coefficient or predetermined different coefficient.Second predetermined process rule includes: be modulated when the first predetermined process rule is direct copying processing；Or when the first predetermined process rule be each sampled signal in institute's taking-up part be multiplied by an identical fixed coefficient or predetermined different coefficient time be also multiplied by corresponding coefficient.Namely, when Part III be direct copying as prefix time, Part II is re-used as suffix or sews in advance after being modulated processing, and when Part III is to be multiplied by corresponding coefficient, Part II is also required to carry out being multiplied by coefficient and carrying out modulation treatment, is re-used as suffix or sews in advance.

Fig. 4 is the schematic diagram processed based on the first common leading symbol acquisition in embodiments of the invention.

In the present embodiment, C section is the direct copying of A section, and the modulation signal segment that B section is A section, as shown in Figure 4, the length of such as A is 1024, the length intercepting C is 520, and the length of B is 504, wherein when C and B is carried out certain process, each sampling of signal can be multiplied by a fixing coefficient, or a different coefficient is multiplied by each sampling.

The scope of data of the B scope of data less than C, namely selects the scope to the part A modulating signal segment B without departing from the scope intercepting the part A as prefix C.Preferably, the length that length sum is A of the length of B and C.

If N_AFor the length of A, if Len_CFor the length of C, Len_BFor modulating the length of signal segment B.If the sampled point sequence number of A is 0,1 ... N_A-1. set N1 as selecting to be copied to the sampled point sequence number of Part I A corresponding to the starting point modulating signal segment Part II B, and N2 is the sampled point sequence number selecting to be copied to Part I A corresponding to the terminal modulating signal segment Part II B.Wherein,

N2=N1+Len_B-1

Generally, what Part II B section was implemented is modulated to frequency modulation, modulates M sequence or other sequences etc., and for frequency modulation in this enforcement, if P1_A (t) is the time-domain expression of A, then the time-domain expression of the first common leading symbol is

$P_{\mathrm{normal}}\left(t\right)=\left\{\begin{array}{cc}P1\_A(t+(N_A-{\mathrm{Len}}_C)T)& 0\&le;t<{\mathrm{Len}}_{C}T\\ P1\_A(t-{\mathrm{Len}}_{C}T)& {\mathrm{Len}}_{C}T\&le;t<(N_A+{\mathrm{Len}}_C)T\\ P1\_A(t-({\mathrm{Len}}_C+N_A-N1)T)e^{j2\mathrm{\&pi;}{f}_{\mathrm{SH}}t}& (N_A+{\mathrm{Len}}_C)T\&le;t<(N_A+{\mathrm{Len}}_C+{\mathrm{Len}}_B)T\\ 0& \mathrm{otherwise}\end{array}\right.$

Wherein, frequency modulation value f_SHSubcarrier in frequency domain interval corresponding to time-domain OFDM symbol and 1/N can be chosen for_AT, wherein T is the sampling period, N_AFor the length of time-domain OFDM symbol, in this example, N_AIt is 1024, takes f_SH=1/1024T.And frequency modulation can arbitrarily select first phase, in order to make correlation peak sharp-pointed, f_SH1/ (Len can also be chosen as_BT)。

As shown in Figure 4, N_A=1024；Len_C=520, Len_B=504, N1=520.The autocorrelation lags that now CA section comprises identical content is N_A, the autocorrelation lags that CB section comprises identical content is N_A+Len_B, and the autocorrelation lags that AB section comprises identical content is Len_B。

Fig. 5 is the schematic diagram processed based on the common leading symbol acquisition of the second in embodiments of the invention.

In like manner, the time-domain expression of the common leading symbol of the second is, it is noted that so that receiving terminal processing method is consistent as far as possible, therefore in the structure of B-C-A, frequency modulation value is just contrary with C-A-B structure, and modulation can arbitrarily select first phase.

$P_{\mathrm{normal}}\left(t\right)=\left\{\begin{array}{cc}P1\_A(t+\left(N1\right)T)e^{-j2{\mathrm{\&pi;f}}_{\mathrm{SH}}(t-{\mathrm{Len}}_{C}T)}& 0\&le;t<{\mathrm{Len}}_{B}T\\ P1\_A(t-({\mathrm{Len}}_B-N_A+{\mathrm{Len}}_C)T)& {\mathrm{Len}}_{B}T\&le;t<({\mathrm{Len}}_B+{\mathrm{Len}}_C)T\\ P1\_A(t-({\mathrm{Len}}_B+{\mathrm{Len}}_C)T)& ({\mathrm{Len}}_B+{\mathrm{Len}}_C)T\&le;t<({\mathrm{Len}}_B+{\mathrm{Len}}_C+N_A)T\\ 0& \mathrm{otherwise}\end{array}\right.$

As it is shown in figure 5, N_A=1024；Len_C=520, Len_B=504, N1=504, the autocorrelation lags that now CA section comprises identical content is N_A, the autocorrelation lags that BC section comprises identical content is Len_B, and the autocorrelation lags that BA section comprises identical content is N_A+Len_B。

Fig. 6 is that in embodiment, the first strengthens the schematic diagram of two three-stage structures in leading symbol.Fig. 7 is that in embodiment, the second strengthens the schematic diagram of two three-stage structures in leading symbol.

Respectively as shown in Figure 6 and Figure 7, strengthen in two different time domain symbols of leading symbol, two time domain main running signal is different, and the three-stage structure of employing is also different, form the first in Fig. 6 respectively by the different successively sequences of two time-domain symbol and strengthen leading symbol and the reinforcement leading symbol of the second in Fig. 7, broadcast for identifying emergent.

On the basis of existing two kinds of common leading symbols, it is possible to 2 symbols are connected, constitute two kinds and strengthen leading symbol.When sending the 1st kind and strengthening leading symbol, represent that system is sending general broadcast service；When sending the second and strengthening leading symbol, represent that system is sending emergent broadcast service.When can also send the first reinforcement leading symbol, represent that system is sending emergent broadcast service, and when sending the second reinforcement leading symbol, represent that system is in transmission general broadcast service.

Strengthening leading symbol to be made up of two general symbols, the main part (i.e. A) of the two general symbol can be different, and so reinforcement leading symbol can transmit twice that the capacity of signaling is general leading symbol or close to twice.

The detection of common leading symbol utilizes CB section, the delay auto-correlation of CA section and BA section obtains peak value, when using reinforcement leading symbol, so that the autocorrelation value of 2 symbols can be added, obtain more robust performance, then 2 respective parameter N1 of symbol (namely N1 is the sampled point sequence number of the A selecting the starting point being copied to modulation signal segment B corresponding) need to meet certain relation, if the N1 of first symbol is N1_1, the N1 of second symbol is N1_2, it is necessary to meet N1_1+N1_2=N_A.And if the modulation that B section is adopted is frequency modulation, frequency deviation value wants contrast.

Represent the symbol of C-A-B structure by sequence number 1, represent the symbol of B-C-A structure by sequence number 2.Then setting the time-domain expression that P1_A (t) is A1, P2_A (t) is the time-domain expression of A2, then the time-domain expression of the first three-stage structure is

$P1\left(t\right)=\left\{\begin{array}{cc}P1\_A(t+(N_A-{\mathrm{Len}}_C)T)& 0\&le;t<{\mathrm{Len}}_{C}T\\ P1\_A(t-{\mathrm{Len}}_{C}T)& {\mathrm{Len}}_{C}T\&le;t<(N_A+{\mathrm{Len}}_C)T\\ P1\_A(t-({\mathrm{Len}}_C+N_A-N1\_1)T)e^{j2\mathrm{\&pi;}{f}_{\mathrm{SH}}t}& (N_A+{\mathrm{Len}}_C)T\&le;t<(N_A+{\mathrm{Len}}_C+{\mathrm{Len}}_B)T\\ 0& \mathrm{otherwise}\end{array}\right.$

The time-domain expression of the second three-stage structure is

$P2\left(t\right)=\left\{\begin{array}{cc}P2\_A(t+(N1\_2)T)e^{-j2{\mathrm{\&pi;f}}_{\mathrm{SH}}(t-{\mathrm{Len}}_{C}T)}& 0\&le;t<{\mathrm{Len}}_{B}T\\ P2\_A(t-({\mathrm{Len}}_B-N_A+{\mathrm{Len}}_C)T)& {\mathrm{Len}}_{B}T\&le;t<({\mathrm{Len}}_B+{\mathrm{Len}}_C)T\\ P2\_A(t-({\mathrm{Len}}_B+{\mathrm{Len}}_C)T)& ({\mathrm{Len}}_B+{\mathrm{Len}}_C)T\&le;t<({\mathrm{Len}}_B+{\mathrm{Len}}_C+N_A)T\\ 0& \mathrm{otherwise}\end{array}\right.$

So, the first time-domain expression strengthening leading symbol is, at this, due to the length that length sum is A of the length of B and C, so, 2N_AIt is the length sum of B, C, A.

So, the time-domain expression of the second reinforcement leading symbol is

Fig. 8 strengthens, based on the first, the schematic diagram that leading symbol acquisition processes in embodiments of the invention.

As shown in Figure 8, a preferred embodiment is, the C section of 2 general symbols, A section are identical with B segment length, N_A=1024；N_cp=520, Len_B=504, only N1 has any different, N1_1=520, N1_2=504.As shown below, respectively the first strengthens leading symbol and the second reinforcement leading symbol.

Take f_SH=1/1024T, then the time-domain expression of the first three-stage structure is

$P1\left(t\right)=\left\{\begin{array}{cc}P1\_A(t+504T)& 0\&le;t<520T\\ P1\_A(t-520T)& 520T\&le;t<1544T\\ P1\_A(t-1024T)e^{j2\mathrm{\&pi;}{f}_{\mathrm{SH}}t}& 1544T\&le;t<2048T\\ 0& \mathrm{otherwise}\end{array}\right.$

Fig. 9 strengthens, based on the second, the schematic diagram that leading symbol acquisition processes in embodiments of the invention.

As it is shown in figure 9, the time-domain expression of the second three-stage structure is

$P2\left(t\right)=\left\{\begin{array}{cc}P2\_A(t+504T)e^{-j2\mathrm{\&pi;}{f}_{\mathrm{SH}}(t-520T)}& 0\&le;t<504T\\ P2\_A\left(t\right)& 504T\&le;t<1024T\\ P2\_A(t-1024T)& 1024T\&le;t<2048T\\ 0& \mathrm{otherwise}\end{array}\right.$

For, the source of the time domain main running signal in above-mentioned steps S1-1, it is generally the case that for general leading symbol, time domain main running signal A is formed time-domain OFDM symbol by frequency-domain OFDM symbol after inverse fourier transform and obtains.

If P1_X is corresponding frequency-domain OFDM symbol, P1_X_iTime-domain OFDM symbol is obtained after inverse discrete Fourier transform changes:

$P1\_A\left(t\right)=\frac{1}{\sqrt{M}}\underset{m=0}{\overset{1023}{\mathrm{\&Sigma;}}}P1\_X\left(m\right)e^{j2\mathrm{\&pi;}\frac{(m-512)}{1024T}t},$ Wherein, M be effective non-zero sub-carriers power and.

P1_X frequency-domain structure and frequency-domain OFDM symbol include virtual subnet carrier wave, signaling sequence (being called SC) subcarrier and fixed sequence program (being called FC) subcarrier three part respectively.

After described signaling sequence subcarrier and described fixed sequence program subcarrier are arranged according to the predetermined rule that is staggered, by described virtual subnet distribution of carriers in its both sides, the described predetermined rule that is staggered comprises any one in following two rule:

The first predetermined rule that is staggered: in oem character set or even strange staggered arrange；And

The second predetermined rule that is staggered: a part of signaling sequence is placed on odd subcarriers, and another part signaling sequence is placed on even subcarriers, and a part of fixed sequence program is placed on odd subcarriers, and another part fixed sequence program is placed on even subcarriers.

The first predetermined rule that is staggered is SC and FC oem character set or even strange staggered discharge, such FC discharges as pilot tone rule, realizing the predetermined rule that is staggered of channel estimating more convenient second then to need part SC sequence to be placed on odd subcarriers, residue SC sequence is placed on even subcarriers；Simultaneously need to part FC sequence is placed on odd subcarriers, residual F C sequence is placed on even subcarriers, it thus is avoided that FC or SC is all placed on even or odd subcarrier, can all decline fall under some special multipath, and such discharge can improve, to channel estimating, the complexity ignored, it therefore it is more excellent selection.

If the length of fixed sequence program be L (number namely carrying effective subcarrier of fixed sequence program is L), signaling sequence length be P (namely the number of effective subcarrier of carrier signaling sequence is P), in the present embodiment, L=P.It should be noted that when the length of fixed sequence program and signaling sequence is inconsistent (such as P > L), it is possible to realize fixed sequence program and signaling sequence by the mode of zero padding sequence subcarrier and be staggered by above-mentioned rule.

Figure 10 is signaling sequence subcarrier in embodiments of the invention, fixed sequence program subcarrier and the virtual subnet carrier wave arrangement schematic diagram according to the first predetermined rule that is staggered.

As shown in Figure 10, this preferred embodiment in, this step includes: fill certain null sequence subcarrier respectively in effective subcarrier both sides to form the frequency-domain OFDM symbol of predetermined length.

Along being the example of 1024 in order to predetermined length, the G=1024-L-P of the length of null sequence subcarrier, (1024-L-P)/2 null sequence subcarrier is filled in both sides.Such as, L=P=353, then G=318,159 null sequence subcarriers are respectively filled in both sides.

The described frequency-domain OFDM symbol generated by the described first predetermined rule that is staggered comprises the steps of

(11st) fixed sequence program generation step: fixed sequence program is made up of 353 plural numbers, its mould is constant, and the n-th value of described fixed sequence program subcarrier is expressed as:

$\mathrm{FC}\left(n\right)=\sqrt{R}{e}^{{\mathrm{j\&omega;}}_n},n=0~352$

Wherein, R is the power ratio of FC and SC, SC_iMould is constant is 1

$R=\frac{\underset{n}{\mathrm{\&Sigma;}}{\left|\mathrm{FC}\left(n\right)\right|}^2}{\underset{n}{\mathrm{\&Sigma;}}{\left|\mathrm{SC}\left(n\right)\right|}^2}$

Described fixed sequence program subcarrier radian value ω_nDetermined by the predetermined stator carrier wave radian value table of first in following table 1；

Table 1 stator carrier wave radian value table (by the first predetermined rule optimization that is staggered)

5.43	2.56	0.71	0.06	2.72	0.77	1.49	6.06	4.82	2.10
										5.62	4.96	4.93	4.84	4.67	5.86	5.74	3.54	2.50	3.75
0.86	1.44	3.83	4.08	5.83	1.47	0.77	1.29	0.16	1.38
										4.38	2.52	3.42	3.46	4.39	0.61	4.02	1.26	2.93	3.84
3.81	6.21	3.80	0.69	5.80	4.28	1.73	3.34	3.08	5.85
										1.39	0.25	1.28	5.14	5.54	2.38	6.20	3.05	4.37	5.41
2.23	0.49	5.12	6.26	3.00	2.60	3.89	5.47	4.83	4.17
										3.36	2.63	3.94	5.13	3.71	5.89	0.94	1.38	1.88	0.13
0.27	4.90	4.89	5.50	3.02	1.94	2.93	6.12	5.47	6.04
										1.14	5.52	2.01	1.08	2.79	0.74	2.30	0.85	0.58	2.25
5.25	0.23	6.01	2.66	2.48	2.79	4.06	1.09	2.48	2.39
										5.39	0.61	6.25	2.62	5.36	3.10	1.56	0.91	0.08	2.52
5.53	3.62	2.90	5.64	3.18	2.36	2.08	6.00	2.69	1.35
										5.39	3.54	2.01	4.88	3.08	0.76	2.13	3.26	2.28	1.32
5.00	3.74	1.82	5.78	2.28	2.44	4.57	1.48	2.48	1.52
										2.70	5.61	3.06	1.07	4.54	4.10	0.09	2.11	0.10	3.18
3.42	2.10	3.50	4.65	2.18	1.77	4.72	5.71	1.48	2.50
										4.89	4.04	6.12	4.28	1.08	2.90	0.24	4.02	1.29	3.61
4.36	6.00	2.45	5.49	1.02	0.85	5.58	2.43	0.83	0.65
										1.95	0.79	5.45	1.94	0.31	0.12	3.25	3.75	2.35	0.73
0.20	6.05	2.98	4.70	0.69	5.97	0.92	2.65	4.17	5.71
										1.54	2.84	0.98	1.47	6.18	4.52	4.44	0.44	1.62	6.09
5.86	2.74	3.27	3.28	0.55	5.46	0.24	5.12	3.09	4.66
										4.78	0.39	1.63	1.20	5.26	0.92	5.98	0.78	1.79	0.75
4.45	1.41	2.56	2.55	1.79	2.54	5.88	1.52	5.04	1.53
										5.53	5.93	5.36	5.17	0.99	2.07	3.57	3.67	2.61	1.72
2.83	0.86	3.16	0.55	5.99	2.06	1.90	0.60	0.05	4.01
										6.15	0.10	0.26	2.89	3.12	3.14	0.11	0.11	3.97	5.15
4.38	2.08	1.27	1.17	0.42	3.47	3.86	2.17	5.07	5.33
										2.63	3.20	3.39	3.21	4.58	4.66	2.69	4.67	2.35	2.44
0.46	4.26	3.63	2.62	3.35	0.84	3.89	4.17	1.77	1.47
										2.03	0.88	1.93	0.80	3.94	4.70	6.12	4.27	0.31	4.85
0.27	0.51	2.70	1.69	2.18	1.95	0.02	1.91	3.13	2.27

5.39	5.45	5.45	1.39	2.85	1.41	0.36	4.34	2.44	1.60
										5.70	2.60	3.41	1.84	5.79	0.69	2.59	1.14	5.28	3.72
5.55	4.92	2.64

(12nd) signaling sequence generation step: symbiosis becomes 512 signaling sequences, i.e. Seq₀, Seq₁... Seq₅₁₁, each signaling sequence Seq₀～Seq₅₁₁Take opposite number, i.e.-Seq more respectively₀～-Seq₅₁₁, receiving terminal utilizes the positive and negative of correlation to distinguish positive sequence or antitone sequence, namely transmits 10bit signaling information altogether, and 512 signaling sequences can be further divided into again 4 groups, often 128 signaling sequences of group, and often 128 signaling sequences generation sub-steps of group are as follows:

1st sub-step: generate consensus sequence zc_i(n), it is the Zadoff-Chu sequence zc (n) of N for length:

${\mathrm{zc}}_i\left(n\right)=e^{-\mathrm{j\&pi;}\frac{u_{i}n(n+1)}{N}},n=0~N-1,i=0~127$

2nd sub-step: by copying twice zc_iN () produces length is 2N's

${{\mathrm{zc}}_i}^{*}\left(n\right)=\left\{\begin{array}{c}{\mathrm{zc}}_i\left(n\right),0\&le;n<N\\ {\mathrm{zc}}_i(n-N),N\&le;n<2N\end{array}\right.,n=0~N-1,i=0~127$

3rd sub-step: fromIn certain specific original position k_iIntercepted length is the sequence of 353, produces SC_i(n):

SC_i(n)=zc_i ^*(k_i-1+n), n=0～352

Often group signaling sequence Seq₀～Seq₁₂₇N value, u_iWith shift value k_iDetermined to table 5 predetermined signaling sequential parameter table by each corresponding table 2 below respectively.

First group of sequence Seq₀～Seq₁₂₇N value, u_iWith shift value k_iAs shown in table 2 below.

2: the first groups of signaling sequence parameters of table

Second group of sequence Seq₁₂₈～Seq₂₅₅Generation step identical with first group of sequence, its N value, u_iWith shift value k_iAs shown in table 3 below.

3: the second groups of signaling sequence parameters of table

3rd group of sequence Seq₂₅₆～Seq₃₈₃Generation step identical with first group of sequence, its N value, u_iWith shift value k_iAs shown in table 4 below table.

4: the three groups of signaling sequence parameters of table

4th group of sequence Seq₃₈₄～Seq₅₁₁Generation step identical with first group of sequence, its N value, u_iWith shift value k_iShown in table 5 below.

5: the four groups of signaling sequence parameters of table

(13rd) arrangement filling step, oem character set discharge will be pressed by the obtained fixed sequence program of described (11) step and described (12) step and signaling sequence, after filling virtual subnet carrier wave, form described frequency-domain OFDM symbol as follows

$P1\_X\left(m\right)=\left\{\begin{array}{cc}0& m=\mathrm{0,1},...,158\\ \mathrm{SC}\left(\frac{m-159}{2}\right)& m=\mathrm{159,161,163},...863\\ \mathrm{FC}\left(\frac{m-160}{2}\right)& m=\mathrm{160,162,164},...,864\\ 0& m=\mathrm{865,866},...1023\end{array}\right.$

Figure 11 is signaling sequence subcarrier in embodiments of the invention, fixed sequence program subcarrier and the virtual subnet carrier wave arrangement schematic diagram according to the second predetermined rule that is staggered.

As shown in figure 11, the signaling sequence of the first half being positioned in figure on the left of dotted line is placed on odd subcarriers, in figure, the signaling sequence of second half part on the right side of dotted line is placed on even subcarriers, and be positioned at the first half fixed sequence program on the left of dotted line and be placed on even subcarriers, the rear section fixed sequence program being positioned on the right side of dotted line is placed on odd subcarriers.I.e. P1_X₀,P1_X₁,…,P1_X₁₀₂₃Producing by the second predetermined rule that is staggered, put strange carrier wave at first half section SC, FC puts even carrier wave, and second half section SC puts even carrier wave, and FC puts strange carrier wave, is exchanged the odd even position of the signaling sequence of front latter half, fixed sequence program.Such fixed sequence program subcarrierSignaling sequence subcarrierResiding odd even position can exchange, and transmission performance is had no effect.

When filling virtual carrier, the null sequence subcarrier length that the left and right sides is filled can also be different, but should not differ too much.

Continue with the specific embodiment providing the frequency domain symbol generated by the second predetermined rule optimization that is staggered.The frequency-domain OFDM symbol generated by the second predetermined rule that is staggered comprises the steps of

(21st) fixed sequence program generation step, this fixed sequence program generation step is identical with (11st) fixed sequence program generation step, only fixed sequence program subcarrier radian value ω_nValue determined by the second predetermined stator carrier wave radian value table；Wherein, the second predetermined stator carrier wave radian value table is by as shown in table 6 below:

Table 6 stator carrier wave radian value table (by the second predetermined rule optimization that is staggered)

0.63	2.34	5.57	6.06	0.55	5.68	2.20	1.58	2.23	4.29
										1.80	3.89	4.08	2.41	5.06	0.10	4.49	4.15	4.99	6.18
0.86	4.31	3.08	0.73	1.67	5.03	4.26	1.73	5.58	2.74
										5.06	1.23	1.67	1.31	2.19	5.90	2.13	3.63	3.90	0.73
4.13	5.90	5.00	1.78	6.10	2.45	2.00	3.61	1.72	5.90
										4.07	0.39	4.72	2.73	4.67	3.56	4.13	3.07	3.74	4.87
1.54	4.28	1.88	2.96	3.07	4.13	1.97	5.69	4.45	2.07
										6.05	4.88	3.39	2.55	5.83	1.86	1.65	4.23	0.46	3.24

1.39	0.19	0.66	4.13	4.83	2.26	2.19	3.06	5.66	0.66
										5.19	5.04	4.62	3.64	0.66	3.52	1.18	4.18	5.93	5.51
1.05	2.18	5.87	1.27	0.92	0.66	5.75	0.16	5.04	0.54
										5.68	0.13	4.76	0.56	1.57	1.59	4.50	3.18	0.82	3.84
4.39	5.53	2.25	3.20	4.04	6.03	4.41	0.32	1.39	5.06
										4.67	3.20	4.63	0.88	6.00	3.99	0.31	3.72	4.17	3.37
4.77	0.30	4.85	2.65	0.88	3.13	1.77	6.05	0.46	1.93
										4.25	1.47	6.12	1.18	3.19	3.00	2.88	5.43	1.01	2.96
2.16	1.17	4.77	6.07	5.32	3.55	1.64	4.35	5.10	3.87
										2.79	4.57	0.51	3.27	2.42	1.52	1.40	0.19	0.35	4.96
6.04	4.90	5.47	5.55	1.40	1.91	4.62	4.22	2.11	4.14
										2.33	2.75	2.68	2.06	4.86	0.34	0.47	3.13	2.97	0.05
5.75	1.51	6.22	2.48	5.10	5.20	2.18	2.31	4.29	3.09
										3.93	5.47	3.22	1.84	4.67	1.35	3.04	0.60	0.62	5.09
6.04	5.39	2.71	2.47	1.86	2.69	1.75	4.94	5.98	1.08
										5.99	3.84	3.67	5.53	1.59	5.60	1.22	5.35	4.44	2.72
5.97	5.08	2.32	0.13	4.52	2.18	1.36	5.72	4.76	2.98
										5.30	1.71	4.31	2.05	1.68	4.61	3.86	2.52	5.36	2.39
3.29	1.47	6.05	0.48	5.57	1.29	4.88	5.97	0.53	0.88
										5.43	2.12	3.97	2.61	2.51	0.50	6.00	5.86	5.35	1.15
5.38	4.42	5.05	0.96	2.41	4.84	0.79	4.99	0.51	1.32
										5.09	1.33	2.83	2.27	4.36	0.53	5.89	4.98	5.33	2.12
2.35	0.59	1.94	1.65	4.44	2.99	4.37	0.01	1.64	0.08
										5.34	4.09	2.14	3.31	3.69	1.38	5.95	3.31	2.44	4.81
4.03	4.80	0.39	3.28	4.57	0.30	4.66	2.21	4.22	2.20
										3.98	4.78	3.97	6.17	5.59	2.78	5.92	3.61	1.41	0.88
5.24	5.47	2.38	2.42	3.22	5.38	5.02	5.10	3.06	2.43
										1.51	4.52	4.85

(22nd) signaling sequence generation step, this signaling sequence generation step is identical with (12nd) signaling sequence generation step,

(23rd) arrangement filling step, after the signaling sequence obtained by (21st) step and (22nd) step and fixed sequence program are occasionally very staggered by odd even again, after zero carrier is filled in the left and right sides, form frequency-domain OFDM symbol as follows

$P1\_X\left(m\right)=\left\{\begin{array}{cc}0& m=\mathrm{0,1},...,158\\ \mathrm{SC}\left(\frac{m-159}{2}\right)& m=159,161,...159+176*2\\ \mathrm{FC}\left(\frac{m-159-1}{2}\right)& m=160,\mathrm{162,160}+176*2\\ \mathrm{FC}\left(\frac{m-159}{2}\right)& m=161+176*\mathrm{2,163}+176*\mathrm{2,159}+352*2\\ \mathrm{SC}\left(\frac{m-159-1}{2}\right)& m=162+176*\mathrm{2,164}+176*2,...160+352*2\\ 0& m=865,...1023\end{array}\right.$

For strengthening leading symbol, the structure of the time-domain OFDM symbol of two time domain main running signal is except the frequency-domain OFDM symbol generation step comprising any one in the claims 4 or claim 5, it addition, the structure of these two time-domain OFDM symbol can also meet at least one in any three below predetermined association rule:

First predetermined association rule: two time-domain OFDM symbol respective signaling sequence centralized procurements take identical.Such as by above-mentioned single symbol transmission 10 bit, so total transmission capacity is 20 bits.

Second predetermined association rule: the fixed sequence program of second time-domain OFDM symbol keeps identical with the fixed sequence program of first time-domain OFDM symbol.

3rd predetermined association rule: the effective sub-carrier positions comprising fixed sequence program and signaling sequence in second time-domain OFDM symbol is overall the moving to left or move to right of effective sub-carrier positions in first time-domain OFDM symbol, and shift value is normally controlled in the scope of 0-5.

Figure 12 and Figure 13 is shift value is 1 schematic diagram carrying out relative integral shift with the two of 2 time domain main running signals with predetermined association rule.

Strengthen the generation preferred embodiment of the frequency domain symbol of A1 and A2 in leading symbol as follows:

The main body of first symbol A1 is identical with the frequency domain symbol of the previously described common leading symbol generated by the second predetermined rule that is staggered, FC and SC sequence and frequency domain putting position and to fill zero carrier identical.

The main body of second symbol A2 is identical with previously described FC and the SC sequence by the common leading symbol of the second predetermined rule generation that is staggered, and effective sub-carrier positions of A2 is that A1 entirety moves to left one.Namely

$P2\_X\left(m\right)=\left\{\begin{array}{cc}0& m=\mathrm{0,1},...,157\\ \mathrm{SC}\left(\frac{m-158}{2}\right)& m=158,160,...158+176*2\\ \mathrm{FC}\left(\frac{m-158-1}{2}\right)& m=159,\mathrm{161,159}+176*2\\ \mathrm{FC}\left(\frac{m-158}{2}\right)& m=160+176*\mathrm{2,162}+176*\mathrm{2,158}+352*2\\ \mathrm{SC}\left(\frac{m-158-1}{2}\right)& m=161+176*\mathrm{2,163}+176*2,...159+352*2\\ 0& m=864,...1023\end{array}\right.$

Figure 14 is the schematic flow sheet of the detailed description of the invention of the method for reseptance of the leading symbol of the present invention.

As shown in figure 14, in the present embodiment, the method for reseptance of leading symbol comprises the steps:

Step S2-1: process to obtain baseband signal to the described physical frame received；

Step S2-2: judge whether there is above-mentioned common leading symbol or the reinforcement leading symbol that expectation receives in described baseband signal；

Step S2-3: when above-mentioned judged result is for being, it is determined that this leading symbol position in physical frame also solves the signaling information entrained by this leading symbol.

Specifically, as described in step S2-1, process to obtain baseband signal to the physical frame received.The signal that usual receiving terminal receives is zero intermediate frequency signals, it is therefore desirable to first it is carried out analog digital conversion to obtain digital signal, then be filtered, down-sampling etc. obtains baseband signal after processing.If it should be noted that what receiving terminal received is intermediate-freuqncy signal, also needing to carry out frequency spectrum shift to it after analog-to-digital conversion process, be then filtered again, down-sampling etc. obtains baseband signal after processing.

As described in step S2-2, it is judged that whether described baseband signal exists above-mentioned common leading symbol or reinforcement leading symbol that expectation receives, specifically includes situations below.

In the present embodiment, if the common leading symbol of the only possible transmission of known transmitting terminal, and when can not send reinforcement leading symbol, it is judged that the common leading symbol that whether there is expectation reception in described baseband signal comprises the steps:

Step S2-21A: according to the C section in the common leading symbol that expectation receives, A section and B section dealing with relationship and/or modulation relation between any two, carry out postponing slip auto-correlation after baseband signal carries out necessary inverse processing and signal demodulation, to obtain three relevant accumulated values of delay；

Step S2-21B: perform mathematical calculations based on, two or three in the relevant accumulated value of these three delay, and this mathematical operation result is carried out peakvalue's checking；

Step S2-21C: if the result of peakvalue's checking meets pre-conditioned, it is determined that there is the common targeting signal that expectation receives in described baseband signal.

Further, step S2-21A can according to the predetermined acquisition rule between any two of the first common leading symbol and the C section of the common leading symbol of the second, A section and B section and/or predetermined process rule, obtain 2 groups and postpone relevant accumulated value, often 3 values of group, and step S2-21B comprises one, two or three postponed in relevant accumulated value three often organized in these 2 groups perform mathematical calculations, and this mathematical operation result is carried out peakvalue's checking.If wherein first group of peakvalue's checking meets pre-conditioned, it is determined that described baseband signal exists the first common targeting signal that expectation receives；If second group of peakvalue's checking meets pre-conditioned, it is determined that described baseband signal exists the common targeting signal of the second that expectation receives；If there are two groups of situations about all meeting, it is necessary to judge separately, such as can with the peak of two groups make an uproar than explicitly judge.

On this basis, if only possible transmission of known transmitting terminal strengthens leading symbol, and when can not send common leading symbol, it is judged that the reinforcement leading symbol that whether there is expectation reception in described baseband signal comprises the steps:

Step S2-22A: the regular and/or predetermined process rule according to C-A-B structure in the common leading symbol that expectation receives and the predetermined acquisition between any two of the C section of B-C-A structure, A section and B section, carry out postponing slip auto-correlation after baseband signal carries out necessity correspondingly inverse processing and signal demodulation, to obtain six relevant accumulated values of delay, these six values can reality only be completed by 3 delay autocorrelators；It addition, when strengthening the FC sequence of 2 symbols of leading symbol and adopting identical, the relevant accumulated value of delay of the combined and spliced part of the C+A section of 2 symbols in front and back also can be obtained；

Step S2-22B: the carrying out that the six of step S2-22A relevant accumulated values of delay have same delay relation is added or is added after phase place adjustment；Obtain three different relevant accumulated values postponed, postpone relevant accumulated value based on these three to perform mathematical calculations with, two, three or four in the relevant accumulated value of delay of the combined and spliced part of the C section A section of 2 symbols in front and back, and this mathematical operation result is carried out peakvalue's checking；

Step S2-22C: if the result of peakvalue's checking meets pre-conditioned, it is determined that there is the reinforcement targeting signal that expectation receives in described baseband signal.

Further, step S2-22A can strengthen leading symbol according to the first and the second strengthens the symbol inside of leading symbol and intersymbol different delay relations, obtain 2 groups and postpone relevant accumulated value, often 6 values of group, and when strengthening the FC sequence of 2 symbols of leading symbol and adopting identical, the C+A section that also can obtain 2 symbols before and after 2 groups postpones relevant accumulated value；And step S2-22B comprises the carrying out postponing relevant accumulated value same delay to 6 often organized in these 2 groups be added；Obtain 2 groups often group comprise 3 different relevant accumulated values postponed；And perform mathematical calculations based on three often organized in these 2 groups postpone the relevant accumulated value combined and spliced part with the C section A section of 2 symbols in front and back one, two, three or four postponed in relevant accumulated value, and this mathematical operation result is carried out peakvalue's checking.If wherein first group of peakvalue's checking meets pre-conditioned, it is determined that described baseband signal exists the first reinforcement targeting signal that expectation receives；If second group of peakvalue's checking meets pre-conditioned, it is determined that described baseband signal exists the second reinforcement targeting signal that expectation receives；If there are two groups of situations about all meeting, it is necessary to judge separately, such as can with the peak of two groups make an uproar than explicitly judge.

If transmitting terminal is likely to send strengthens leading symbol, when being likely to the common leading symbol of transmission, the common leading symbol detection that then should carry out above-mentioned S2-21 also to carry out the reinforcement leading symbol detection of above-mentioned S2-22, at this, it is no longer repeated, the structure of common leading symbol is necessarily comprised owing to strengthening leading symbol, when both meeting pre-conditioned, if the peak value strengthening leading symbol is better than the peak value of common leading symbol by certain threshold value, then it is judged as strengthening leading symbol, is otherwise judged as common leading symbol.

The embodiment being previously mentioned, the peak value of common leading symbol obtains block diagram can be as shown in Figure 15 and Figure 16.Figure 15 be in embodiments of the invention corresponding to three-stage structure CAB the first common leading symbol peak value obtain logical schematic.Figure 16 be in embodiments of the invention corresponding to three-stage structure BCA the common leading symbol of the second peak value obtain logical schematic.

Identical part in Figure 15 and Figure 16 has only to a set of reception resource, it is illustrated that separate to clearly state.Wherein C, A, the B in figure represents that C section, the length of A section and B segment signal, and moving average filter can be power normalization wave filter respectively.In detail in this figure, C+B=A is met.

The peak value acquisition block diagram strengthening leading symbol can be as shown in Figure 17 and Figure 18.Figure 17 be in embodiments of the invention the first strengthen leading symbol peak value obtain logical schematic.Figure 18 be in embodiments of the invention the second strengthen leading symbol peak value obtain logical schematic.

Specifically, as described in step S2-3, when above-mentioned judged result is for being, it is determined that this leading symbol position in physical frame also solves the signaling information entrained by this leading symbol and comprises step in detail below.

Determine that this leading symbol position in physical frame includes: determine this leading symbol position in physical frame based on the result meeting pre-conditioned peakvalue's checking.

If there is the leading symbol that expectation receives, the part value big according to peak value or maximum determine the position that leading symbol occurs in physical frame.The result utilizing peakvalue's checking can also carry out fractional part of frequency offset estimation.

Described step S2-3 solves the frequency-region signal that the signaling information entrained by this leading symbol comprises the steps: to utilize all or part of time domain waveform of leading symbol and/or all or part of time domain waveform of this leading symbol to obtain after Fourier transformation, to solve the signaling information entrained by this leading symbol.

The time-domain signal corresponding with signaling sequence t easet ofasubcarriers or this signaling sequence t easet ofasubcarriers by the signal comprising signaling sequence subcarrier carries out computing, to solve in this leading symbol the signaling information entrained by signaling sequence subcarrier.Wherein signaling sequence t easet ofasubcarriers produces based on known signaling sequence set.

Wherein, the signal comprising signaling sequence subcarrier includes: all or part of time domain waveform of the leading symbol received, or 1 or 2 frequency-domain OFDM symbols that from leading symbol, intercepting 1 or 2 main body OFDM symbol obtain after being fourier transformed.Signaling sequence t easet ofasubcarriers is to be filled, by each signaling sequence in signaling sequence set, the set formed to effective subcarrier.

Specifically, the N of 1 or 2 corresponding ODFM symbol main body is intercepted_A1 or 2 the frequency-domain OFDM symbols that the time-domain signal of length obtains after carrying out Fourier transform；Then, remove zero carrier, take out 1 or 2 frequency domain signaling sub-carriers receiving according to signaling sub-carriers position.It is carried out specific mathematical operation with above-mentioned channel estimation value and known signaling sequence subcarrier collection, completes frequency domain decoding function.

Such as, if i=0:M-1, M are signaling sub-carriers number, j=0:2^P-1, P is that frequency domain is transmitted makes bit number, and namely corresponding signaling sub-carriers collection has 2^PIndividual element, and each element correspondence length is the sequence of M, H_iFor the channel estimation value that each signaling sub-carriers is corresponding, SC_rec_iFor the frequency domain signaling sub-carriers value received,The i-th value in jth element is concentrated for signaling sequence subcarrier.Then ${\mathrm{corr}}_j=\mathrm{Re}(\underset{i=0}{\overset{M-1}{\mathrm{\&Sigma;}}}\mathrm{SC}\_{\mathrm{rec}}_i{H_i}^{*}{\mathrm{SC}}_i^{*j})j=0:2^P-1,$ Take max (corr_j) corresponding to j, namely obtain the signaling information of frequency-domain transmission.

In other embodiments, said process can also carry out in time domain, it is relevant that the time domain signaling waveform collection utilizing the frequency domain symbol of the corresponding length that known signaling sequence subcarrier collection generates after in position zero padding corresponding after Fourier inversion directly carries out synchronization with the time-domain received signal obtaining multipath accurate location, take that of correlation maximum absolute value, the signaling information of frequency-domain transmission can also be solved, repeat no more here.

Further, receiving terminal can also utilize fixed sequence program to do integer frequency offset estimation or channel estimating, and namely the method for reseptance of the leading symbol of the present invention can also comprise the following steps:

1) according to being determined this leading symbol position in physical frame, the signal comprising stator carrier wave is intercepted；

2) time-domain signal that this signal comprising stator carrier wave is corresponding with frequency domain stator carrier wave sequence or this frequency domain stator carrier wave sequence is carried out computing, to obtain integer frequency offset estimation or channel estimating.

Specifically, the present embodiment comprises the steps: 1) according to being determined this leading symbol position in physical frame, intercept the signal comprising stator carrier wave；2) time-domain signal that this signal comprising stator carrier wave is corresponding with frequency domain stator carrier wave sequence or this frequency domain stator carrier wave sequence is carried out computing, to obtain integer frequency offset estimation or channel estimating.

Wherein, the signal comprising stator carrier wave described in includes: all or part of time domain waveform of the leading symbol received, or the frequency-domain OFDM symbol that intercepting time-domain OFDM symbol obtains after being fourier transformed from leading symbol.

Receiving terminal is detailed below and carries out two kinds of methods of integer frequency offset estimation.

Method 1:

According to the leading symbol detected position in physical frame, intercept all or part of the time domain waveform of the leading symbol received.Adopt the mode of frequency sweep, namely with fixing frequency change step footpath (such as, corresponding integer frequency offset interval), after upper for the modulation of this part time domain waveform different frequency deviation, obtain several time-domain signals:T is the sampling period, f_sFor sample frequency.And known frequency domain fixed sequence program subcarrier to carry out time-domain signal corresponding to inverse fourier transform be A2, using A2 as known signal and each A1_yCarry out sliding and be correlated with, choose that A1 that maximum correlation peaks occurs_y, then its frequency deviation value y modulated is integer frequency offset estimation value.

Wherein, the frequency deviation region of the required antagonism of swept frequency range correspondence system, such as, it is necessary to resist the frequency deviation of positive and negative 500K, and systematic sampling rate is 9.14M, leading symbol main body is 1K length, then swept frequency range isI.e. [-57,57].

In frequency sweep, used being correlated with can use FFT and IFFT to carry out equivalent realization, repeats no more here.

Method 2:

Intercept the time-domain signal of corresponding ODFM symbol main body in leading symbol and obtain frequency-domain OFDM symbol after carrying out Fourier transform, the frequency-domain OFDM symbol that conversion obtains is carried out the cyclic shift of above-mentioned swept frequency range, and carry out dot interlace difference by the interval of FC 2 fixed sequence program subcarriers in position and front and back on sub-carriers and be multiplied, and carry out related operation with the dot interlace difference multiplied value of known fixed sequence subcarrier, obtain a series of correlation, choose the cyclic shift that maximum related value is corresponding, can obtain accordingly obtaining integer frequency offset estimation value.

Further, when judging the reinforcement leading symbol that there is expectation reception in described baseband signal, , if the shift value strengthening the effective sub-carrier positions of leading symbol is even number, 2 the frequency-domain OFDM symbols that also obtain after the time-domain signal of 2 corresponding ODFM symbol main bodys can be carried out Fourier transform, 2 frequency-domain OFDM symbols that conversion obtains are carried out simultaneously the same loop displacement of above-mentioned swept frequency range, each symbol reception value after displacement and this symbol known fixed sequence sub-carrier values conjugate multiplication, and after the multiplied value of 2 same sub-carrier positions of symbol is carried out conjugate multiplication again, the conjugate multiplication value of all effective FC subcarrier of 2 symbol common location is added up, namelyJ ∈ swept frequency range, R_i,1,jIt is the reception value on corresponding FC position, R after shifted j on first symbol frequency domain_i,2,jIt is the reception value on corresponding FC position after shifted j on second symbol frequency domain,WithThe respectively FC given value on certain subcarrier of first symbol and second symbol, M is the total number of known FC, so obtain a series of accumulated value corresponding to each cyclic shift value, choose the cyclic shift that maximum accumulated value is corresponding, can obtain accordingly obtaining integer frequency offset estimation value.

The signal comprising fixed sequence program subcarrier received is utilized to complete channel estimating with known frequency domain fixed sequence program subcarrier and/or its time-domain signal carrying out inverse fourier transform corresponding, equally possible selection carries out in time domain and/or carries out at frequency domain, does not repeat them here.

Claims (29)

1. the generation method of a leading symbol, it is characterised in that comprise the steps:

The time-domain symbol of any one three-stage structure having in following two kinds is generated based on obtained described time domain main running signal；And

Leading symbol is generated based on time-domain symbol one or two described,

Wherein, the first described three-stage structure is: the suffix of the prefix that described time domain main running signal, rear portion based on this time domain main running signal generate and the modulated generation in rear portion based on this time domain main running signal,

Three-stage structure described in the second is: prefix that described time domain main running signal, rear portion based on this time domain main running signal generate and the sewing in advance of the modulated generation in rear portion based on this time domain main running signal,

Generating common leading symbol when based on a described time-domain symbol, when having the described time-domain symbol of different three-stage structure based on two, splicing generates and strengthens leading symbol.

2. the generation method of leading symbol as claimed in claim 1, it is characterised in that:

Wherein, described time domain main running signal is that the frequency-domain OFDM symbol to predetermined length carries out inverse discrete Fourier transform and changes and the time-domain OFDM symbol that obtains.

3. the generation method of leading symbol as claimed in claim 2, it is characterised in that:

Wherein, described frequency-domain OFDM symbol includes virtual subnet carrier wave, signaling sequence subcarrier and fixed sequence program subcarrier,

After described signaling sequence subcarrier and described fixed sequence program subcarrier are arranged according to the predetermined rule that is staggered, by described virtual subnet distribution of carriers in its both sides,

The described predetermined rule that is staggered comprises any one in following two rule:

The first predetermined rule that is staggered: in oem character set or even strange staggered arrange；And

The second predetermined rule that is staggered: a part of signaling sequence is placed on odd subcarriers, and another part signaling sequence is placed on even subcarriers, and a part of fixed sequence program is placed on odd subcarriers, and another part fixed sequence program is placed on even subcarriers.

4. the generation method of leading symbol as claimed in claim 3, it is characterised in that:

The described frequency-domain OFDM symbol generated by the described first predetermined rule that is staggered comprises the steps of

(11st) fixed sequence program generation step: fixed sequence program is made up of 353 plural numbers, its mould is constant, and the n-th value of described fixed sequence program subcarrier is expressed as:

$\mathrm{FC}\left(n\right)=\sqrt{R}{e}^{j{\mathrm{\&omega;}}_n},n=0~352$

Wherein, R is the power ratio of FC and SC, SC_iMould is constant is 1

$R=\frac{\underset{n}{\mathrm{\&Sigma;}}{\left|\mathrm{FC}\left(n\right)\right|}^2}{\underset{n}{\mathrm{\&Sigma;}}{\left|\mathrm{SC}\left(n\right)\right|}^2}$

Described fixed sequence program subcarrier radian value ω_nDetermined by the first predetermined stator carrier wave radian value table；

(12nd) signaling sequence generation step: symbiosis becomes 512 signaling sequences, i.e. Seq₀, Seq₁... Seq₅₁₁, each signaling sequence Seq₀～Seq₅₁₁Take opposite number, i.e.-Seq more respectively₀～-Seq₅₁₁, receiving terminal utilizes the positive and negative of correlation to distinguish positive sequence or antitone sequence, namely transmits 10bit signaling information altogether, and 512 signaling sequences can be further divided into again 4 groups, often 128 signaling sequences of group, and often 128 signaling sequences generation sub-steps of group are as follows:

1st sub-step: generate consensus sequence zc_i(n), it is the Zadoff-Chu sequence zc (n) of N for length:

${\mathrm{zc}}_i\left(n\right)=e^{-\mathrm{j\&pi;}\frac{u_{i}n(n+1)}{N}},n=0~N-1,i=0~127$

2nd sub-step: by copying twice zc_iN () produces length is 2N's

${\mathrm{zc}}_i^{*}\left(n\right)=\left\{\begin{array}{c}{\mathrm{zc}}_i\left(n\right),0\&le;n<N\\ {\mathrm{zc}}_i(n-N),N\&le;n<2N\end{array}\right.,n=0~N-1,i=0~127$

3rd sub-step: fromIn certain specific original position k_iIntercepted length is the sequence of 353, produces SC_i(n):

${\mathrm{SC}}_i\left(n\right)={\mathrm{zc}}_i^{*}(k_i-1+n),n=0~352$

Often group signaling sequence Seq₀～Seq₁₂₇N value, u_iWith shift value k_iDetermined by each corresponding predetermined signaling sequential parameter table respectively；And

(13rd) arrangement filling step, oem character set discharge will be pressed by the obtained fixed sequence program of described (11) step and described (12) step and signaling sequence, after filling virtual subnet carrier wave, form described frequency-domain OFDM symbol as follows

$P1\_X\left(m\right)=\left\{\begin{array}{cc}0& m=\mathrm{0,1},\&CenterDot;\&CenterDot;\&CenterDot;,158\\ \mathrm{SC}\left(\frac{m-158}{2}\right)& m=\mathrm{159,161,163},...863\\ \mathrm{FC}\left(\frac{m-160}{2}\right)& m=\mathrm{160,162,164},...864\\ 0& m=\mathrm{865,866},...1023\end{array}\right.$

5. the generation method of leading symbol as claimed in claim 4, it is characterised in that:

The described frequency-domain OFDM symbol generated by the described second predetermined rule that is staggered comprises the steps of

(21st) fixed sequence program generation step, this fixed sequence program generation step is identical with described (11st) fixed sequence program generation step, only described fixed sequence program subcarrier radian value ω_nValue determined by the second predetermined stator carrier wave radian value table；

(22nd) signaling sequence generation step, this signaling sequence generation step is identical with described (12nd) signaling sequence generation step,

(23rd) arrangement filling step, after the signaling sequence obtained by described (21st) step and described (22nd) step and fixed sequence program are occasionally very staggered by odd even again, the left and right sides forms described frequency-domain OFDM symbol after filling zero carrier as follows

$P1\_X\left(m\right)=\left\{\begin{array}{cc}0& m=\mathrm{0,1}\&CenterDot;\&CenterDot;\&CenterDot;,158\\ \mathrm{SC}\left(\frac{m-159}{2}\right)& m=\mathrm{159,161},...159+176*2\\ \mathrm{FC}\left(\frac{m-159-1}{2}\right)& m=\mathrm{160,162,160}+176*2\\ \mathrm{FC}\left(\frac{m-159}{2}\right)& m=161+176*\mathrm{2,163}+176*\mathrm{2,159}+352*2\\ \mathrm{SC}\left(\frac{m-159-1}{2}\right)& m=162+176*\mathrm{2,164}+176*2,...160+352*2\\ 0& m=865,...1023\end{array}\right.$

6. the generation method of leading symbol as claimed in claim 3, it is characterised in that:

Wherein, for described reinforcement leading symbol, the structure of the time-domain OFDM symbol of two described time domain main running signal is except comprising in the claims 4 or claim 5 the frequency-domain OFDM symbol generation step described in any one, it addition, the structure of these two time-domain OFDM symbol can also meet at least one in any three below predetermined association rule:

First predetermined association rule: two time-domain OFDM symbol respective signaling sequence centralized procurements take identical；

Second predetermined association rule: the fixed sequence program of second time-domain OFDM symbol keeps identical with the fixed sequence program of first time-domain OFDM symbol；

3rd predetermined association rule: the effective sub-carrier positions comprising fixed sequence program and signaling sequence in second time-domain OFDM symbol is overall the moving to left or move to right of effective sub-carrier positions in first time-domain OFDM symbol, and shift value is normally controlled in the scope of 0-5.

7. the generation method of leading symbol as claimed in claim 1, it is characterised in that:

In described prefix, described suffix or the described generation step sewed in advance, comprise the steps of

Using described time domain main running signal as Part I, the least significant end of neat described Part I takes out a part according to the predetermined rule that obtains, the front portion processing and copying to this Part I is carried out to generate Part III thus as described prefix according to the first predetermined process rule, simultaneously, a part is taken out from the rear portion of described Part I according to the predetermined rule that obtains, carry out processing and copy to the rear portion of this Part I or process according to the second predetermined process rule and copy to the front portion of described prefix to generate Part II thus corresponding as described suffix or described sew in advance respectively.

8. the generation method of leading symbol as claimed in claim 7, it is characterised in that

Wherein, described predetermined acquisition rule includes:

If Len_BFor the length of described Part II, Len_CFor the length of described Part III, Len_B≤Len_C, separately setting N1 as selecting to be copied to the sampled point sequence number of described Part I corresponding to the starting point of described Part II, N2 is the sampled point sequence number of the described Part I that the terminal selecting to be copied to described Part II is corresponding, then meet below equation: N2=N1+Len_B-1。

9. the generation method of leading symbol as claimed in claim 7, it is characterised in that:

Wherein, described first predetermined process rule includes: direct copying；Or

To each sampled signal in taking-up part be multiplied by an identical fixed coefficient or predetermined different coefficient,

Described second predetermined process rule includes: be modulated when described first predetermined process rule is direct copying processing；Or

When described first predetermined process rule be each sampled signal in institute's taking-up part be multiplied by an identical fixed coefficient or predetermined different coefficient time be also multiplied by corresponding coefficient after carry out modulation treatment.

10. the generation method of leading symbol as claimed in claim 7, it is characterised in that:

Wherein, described common leading symbol is based on same described time domain main running signal, by any one in the first three-stage structure described and described the second three-stage structure for identifying emergent broadcast.

11. the generation method of leading symbol as claimed in claim 10, it is characterised in that

Described Part III is based on described Part I direct copying and obtains, and described Part II is based on described Part I frequency modulation and obtains,

To divide into the time-domain expression that P1_A (t) is described Part I, then the time-domain expression of the first three-stage structure described meets following relation:

Wherein, frequency modulation value f_SHSubcarrier in frequency domain interval corresponding to time-domain OFDM symbol and 1/N can be chosen for_AT, and modulation first phase arbitrarily select, T is the sampling period, N_AFor the length of time-domain OFDM symbol, Len_BFor the length of described Part II, Len_CFor the length of described Part III, N1 is the sampled point sequence number of described Part I corresponding to the starting point selecting to be copied to described Part II.

12. the generation method of leading symbol as claimed in claim 11, it is characterised in that

To divide into the time-domain expression that P1_A (t) is described Part I, then the time-domain expression of described the second three-stage structure meets following relation:

Wherein, the frequency modulation value in this second three-stage structure is contrary with the frequency modulation value in the first three-stage structure described is-f_SH, and modulation can arbitrarily select first phase.

13. the generation method of leading symbol as claimed in claim 7, it is characterised in that:

Wherein, in two described time-domain symbol of difference of described reinforcement leading symbol, two described time domain main running signal is different, and the described three-stage structure of employing is also different, form the first respectively by the different successively sequences of two described time-domain symbol and strengthen leading symbol and the second reinforcement leading symbol, broadcast for identifying emergent.

14. the generation method of leading symbol as claimed in claim 13, it is characterised in that

Sequence number 1 is utilized to represent the symbol of the first three-stage structure described, and sequence number 2 represents the symbol of described the second three-stage structure, then setting P1_A (t) is the time-domain expression of time domain main running signal in the first three-stage structure described, P2_A (t) is the time-domain expression of time domain main running signal in described the second three-stage structure

Wherein, f_SHSubcarrier in frequency domain interval corresponding to time-domain OFDM symbol and 1/N can be chosen for_AT, T are the sampling period, N_AFor the length of time-domain OFDM symbol, Len_BFor the length of described Part II, Len_CFor the length of described Part III, N1_1, N1_2 is the sampled point sequence number of described Part I corresponding to the starting point selecting to be copied to described Part II,

Then the time-domain expression of the symbol of the first three-stage structure described is:

Then the time-domain expression of the symbol of described the second three-stage structure is:

15. the generation method of leading symbol as claimed in claim 14, it is characterised in that

Wherein, the first time-domain expression strengthening leading symbol described is:

Described the second strengthens the time-domain expression of leading symbol:

16. the method for reseptance of a leading symbol, it is characterised in that comprise the steps:

Step S2-1: process to obtain baseband signal to the physical frame received；

Step S2-2: judge whether there is the common leading symbol described in claim 1 or the reinforcement leading symbol that expectation receives in described baseband signal；

Step S2-3: when being judged as YES, it is determined that this leading symbol position in physical frame also solves the signaling information entrained by this leading symbol.

17. the method for reseptance of leading symbol as claimed in claim 16, it is characterised in that

Described physical frame is processed obtain baseband signal comprise the steps:

When the signal received is zero intermediate frequency signals, after analog digital conversion, then filter, down-sampling process obtain described baseband signal,

When the signal received is intermediate-freuqncy signal, frequency spectrum shift after analog digital conversion, then filter, down-sampling process obtain described baseband signal.

18. the method for reseptance of leading symbol as claimed in claim 16, it is characterised in that

In the described common leading symbol situation of the only possible transmission of known transmitting terminal, it is judged that the described common leading symbol that whether there is expectation reception in described baseband signal comprises the steps:

Step S2-21A: obtain rule and/or predetermined process rule according to the Part III in the common leading symbol that as described in claim 7 expectation receives, Part I and Part II between any two predetermined, carry out postponing slip auto-correlation after baseband signal carries out correspondingly inverse processing and signal demodulation, to obtain three relevant accumulated values of delay；

Step S2-21B: at least one delay in relevant accumulated value based on these three performs mathematical calculations, and this mathematical operation result is carried out peakvalue's checking；And

Step S2-21C: if the result of peakvalue's checking meets pre-conditioned, it is determined that there is the common targeting signal that expectation receives in described baseband signal.

19. the method for reseptance of leading symbol as claimed in claim 18, it is characterised in that

Wherein, described step S2-21A according to the first common leading symbol and the Part III of the common leading symbol of the second, Part I and Part II different disposal relation and/or modulation relation, can obtain 2 groups and postpone relevant accumulated values, often 3 values of group,

Further, described step S2-21B comprises in the relevant accumulated value of three delays often organized in the described relevant accumulated value of 2 groups of delays, at least one performs mathematical calculations, and this mathematical operation result is carried out peakvalue's checking,

Wherein, if the result of first group of peakvalue's checking meets pre-conditioned, it is determined that described baseband signal exists the first common targeting signal that expectation receives；

If the result of second group of peakvalue's checking meets pre-conditioned, it is determined that described baseband signal exists the common targeting signal of the second that expectation receives；

If the result of two groups all meets pre-conditioned, further with two groups of peaks make an uproar than explicitly judge.

20. the method for reseptance of leading symbol as claimed in claim 16, it is characterised in that.

When the described reinforcement leading symbol of the only possible transmission of known transmitting terminal, it is judged that the described reinforcement leading symbol that whether there is expectation reception in described baseband signal comprises the steps:

Step S2-22A: according to the Part III of the first described three-stage structure in the reinforcement leading symbol that expectation receives and three-stage structure described in the second, the predetermined acquisition between any two of Part I and Part II is regular and/or predetermined process is regular, carry out postponing slip auto-correlation after baseband signal carries out correspondingly inverse processing and signal demodulation, to obtain six relevant accumulated values of delay, actual in 3 delay correlators acquisitions, wherein, when strengthening the fixed sequence program of two symbols of leading symbol and adopting identical, also can obtain the relevant accumulated value of delay of the Part III of former and later two symbols and the combined and spliced part of Part I；

Step S2-22B: the carrying out that the six of described step S2-22A relevant accumulated values of delay have same delay relation is added or is added after phase place adjustment, obtain three different relevant accumulated values postponed, postpone relevant accumulated value based on these three to perform mathematical calculations with at least one in the relevant accumulated value of delay of the combined and spliced part of the Part III of former and later two symbols and Part I, and this mathematical operation result is carried out peakvalue's checking；

Step S2-22C: if the result of peakvalue's checking meets pre-conditioned, it is determined that there is the described reinforcement targeting signal that expectation receives in described baseband signal.

21. the method for reseptance of leading symbol as claimed in claim 20, it is characterised in that.

Step S2-22A can strengthen leading symbol according to the first and the second strengthens the symbol inside of leading symbol and intersymbol different delay relations, obtain 2 groups and postpone relevant accumulated value, often 6 values of group, and when strengthening the fixed sequence program of two symbols of leading symbol and adopting identical, the section that also can obtain the Part III of 2 groups of former and later two symbols and the combined and spliced part of Part I postpones relevant accumulated value, further, step S2-22B comprises the carrying out postponing relevant accumulated value same delay to 6 often organized in these 2 groups to be added；Obtain 2 groups often group comprise 3 different relevant accumulated values postponed；And perform mathematical calculations based at least one in the relevant accumulated value of delay of three often organized in these the 2 groups combined and spliced parts postponing relevant accumulated value and the Part III of former and later two symbols and Part I, and this mathematical operation result is carried out peakvalue's checking,

Wherein, if first group of peakvalue's checking meets pre-conditioned, it is determined that described baseband signal exists the first reinforcement targeting signal described that expectation receives；

If second group of peakvalue's checking meets pre-conditioned, it is determined that described baseband signal exists described the second reinforcement targeting signal that expectation receives；

If two groups of situations about all meeting, need further with two groups of peaks make an uproar than explicitly judge.

22. the method for reseptance of leading symbol as claimed in claim 16, it is characterised in that.

When transmitting terminal be likely to send strengthen leading symbol be likely to transmission common leading symbol, then should carry out following common leading symbol detecting step also to carry out as follows reinforcement leading symbol detecting step:

Common leading symbol detecting step:

Step S2-21A: obtain rule and/or predetermined process rule according to the Part III in the common leading symbol that as described in claim 7 expectation receives, Part I and Part II between any two predetermined, carry out postponing slip auto-correlation after baseband signal carries out correspondingly inverse processing and signal demodulation, to obtain three relevant accumulated values of delay；

Step S2-21B: at least one delay in relevant accumulated value based on these three performs mathematical calculations, and this mathematical operation result is carried out peakvalue's checking；And

Step S2-21C: if the result of peakvalue's checking meets pre-conditioned, it is determined that there is the common targeting signal that expectation receives in described baseband signal,

Strengthen leading symbol detecting step:

Step S2-22A: according to the Part III of the first described three-stage structure in the reinforcement leading symbol that expectation receives and three-stage structure described in the second, the predetermined acquisition between any two of Part I and Part II is regular and/or predetermined process is regular, carry out postponing slip auto-correlation after baseband signal carries out correspondingly inverse processing and signal demodulation, to obtain six relevant accumulated values of delay, wherein, when strengthening the fixed sequence program of two symbols of leading symbol and adopting identical, also can obtain the relevant accumulated value of delay of the Part III of former and later two symbols and the combined and spliced part of Part I；

Step S2-22B: the carrying out that the six of described step S122A relevant accumulated values of delay have same delay relation is added or is added after phase place adjustment, obtain three different relevant accumulated values postponed, postpone relevant accumulated value based on these three to perform mathematical calculations with at least one in the relevant accumulated value of delay of the combined and spliced part of the Part III of former and later two symbols and Part I, and this mathematical operation result is carried out peakvalue's checking；

Step S2-22C: if the result of peakvalue's checking meets pre-conditioned, it is determined that there is the described reinforcement targeting signal that expectation receives in described baseband signal,

Wherein, when the result of both peakvalue's checking all meets pre-conditioned, if the peak value of described reinforcement leading symbol is better than the peak value of described common leading symbol by certain threshold value, then it is judged as strengthening leading symbol, is otherwise judged as common leading symbol.

23. the method for reseptance of leading symbol as claimed in claim 16, it is characterised in that

Described determine that this leading symbol position in physical frame includes: determine this leading symbol position in physical frame based on the result meeting pre-conditioned peakvalue's checking,

If there is the leading symbol that expectation receives, the residing partial value big according to peak value or maximum are determined position that leading symbol occurs in physical frame or carry out fractional part of frequency offset estimation.

24. the method for reseptance of leading symbol as claimed in claim 16, it is characterised in that

The frequency-region signal utilizing all or part of time domain waveform of leading symbol and/or all or part of time domain waveform of this leading symbol to obtain after Fourier transformation, comprises the steps: with the signaling information solved entrained by this leading symbol

The time-domain signal corresponding with signaling sequence t easet ofasubcarriers or this signaling sequence t easet ofasubcarriers by the signal comprising signaling sequence subcarrier carries out computing, to solve in this leading symbol the signaling information entrained by signaling sequence subcarrier, wherein signaling sequence t easet ofasubcarriers produces based on known signaling sequence set.

25. the method for reseptance of leading symbol as claimed in claim 16, it is characterised in that also comprise the steps:

1) according to being determined this leading symbol position in physical frame, the signal comprising stator carrier wave is intercepted；

2) time-domain signal that this signal comprising stator carrier wave is corresponding with frequency domain stator carrier wave sequence or this frequency domain stator carrier wave sequence is carried out computing, to obtain integer frequency offset estimation or channel estimating.

26. the method for reseptance of leading symbol as claimed in claim 25, it is characterised in that

Obtain integer frequency offset estimation to comprise the steps:

According to the leading symbol detected position in physical frame, intercept all or part of the time domain waveform of the leading symbol received；

The mode adopting frequency sweep after upper for the modulation of this part time domain waveform different frequency deviation, will obtain several time-domain signals:T is the sampling period, f_sFor sample frequency；And

It is A2 that known frequency domain fixed sequence program subcarrier carries out time-domain signal corresponding to inverse fourier transform, using A2 as known signal and each A1_yCarry out sliding and be correlated with, choose that A1 that maximum correlation peaks occurs_y, then its frequency deviation value y modulated is integer frequency offset estimation value,

Wherein, the frequency deviation region of the required antagonism of swept frequency range correspondence system.

27. the method for reseptance of leading symbol as claimed in claim 25, it is characterised in that

Obtain integer frequency offset estimation to comprise the steps:

Intercept the time-domain signal of corresponding ODFM symbol main body in leading symbol and obtain frequency-domain OFDM symbol after carrying out Fourier transform, the frequency-domain OFDM symbol that conversion obtains is carried out the cyclic shift of swept frequency range, and carry out dot interlace difference by the interval of fixed sequence program 2 fixed sequence program subcarriers in position and front and back on sub-carriers and be multiplied, and carry out related operation with the dot interlace difference multiplied value of known fixed sequence subcarrier, obtain a series of correlation, choose the cyclic shift that maximum related value is corresponding, can obtain accordingly obtaining integer frequency offset estimation value

Wherein, the frequency deviation region of the required antagonism of swept frequency range correspondence system.

28. the method for reseptance of leading symbol as claimed in claim 25, it is characterised in that

Obtain integer frequency offset estimation to comprise the steps:

When judging the reinforcement leading symbol that there is expectation reception in described baseband signal, if the shift value of effective sub-carrier positions of 2 symbols is even number in reinforcement leading symbol, 2 the frequency-domain OFDM symbols that also obtain after the time domain main running signal of 2 corresponding ODFM symbols can be carried out Fourier transform, 2 frequency-domain OFDM symbols that conversion obtains are carried out simultaneously the same loop displacement of swept frequency range, each symbol reception value after displacement and this symbol known fixed sequence sub-carrier values conjugate multiplication, and after the multiplied value of 2 same sub-carrier positions of symbol is carried out conjugate multiplication again, the conjugate multiplication value of all effective fixed sequence program subcarrier of 2 symbol common location is added up, wherein, the frequency deviation region of the required antagonism of swept frequency range correspondence system,

Namely ${\mathrm{corr}}_j=\mathrm{Re}\left(\underset{i=0}{\overset{M-1}{\mathrm{\&Sigma;}}}{R}_{i,l,j}{\mathrm{FC}}_{i,1}^{*}{\left(R_{i,2,j}{\mathrm{FC}}_{i,2}^{*}\right)}^{*}\right)$ J ∈ swept frequency range,

R_i,1,jIt is the reception value on corresponding FC position, R after shifted j on first symbol frequency domain_i,2,jIt is the reception value on corresponding FC position after shifted j on second symbol frequency domain,WithThe respectively FC given value on certain subcarrier of first symbol and second symbol, M is the total number of known FC, obtain a series of accumulated value corresponding to each cyclic shift value, choose the cyclic shift that maximum accumulated value is corresponding, can obtain accordingly obtaining integer frequency offset estimation value.

29. the method for reseptance of leading symbol as claimed in claim 25, it is characterised in that

Wherein, utilize the signal comprising fixed sequence program subcarrier received to complete channel estimating with known frequency domain fixed sequence program subcarrier and/or its time-domain signal carrying out inverse fourier transform corresponding, complete in time domain and/or at frequency domain.