CN103595677A - A method and an apparatus for beacon signal generation in a communication system - Google Patents

Abstract

The invention discloses a method and an apparatus for beacon signal generation in a communication system. The method specifically comprises the following steps: a frequency domain synchronization signal generation module generates frequency domain synchronization signals with the length of LxNI, wherein the NI represents the number of sub-bands occupied by a frequency spectrum mode adopted by to-be-sent signals, and the L represents the number of effective subcarriers carried by each sub-band of beacon signals; then a mapping module carries out subcarrier mapping on the frequency domain synchronization signals; an inverse Fourier transform module carries out inverse Fourier transforming on the frequency domain synchronization signals which have gone through subcarrier mapping to obtain time domain synchronization signals; and finally, a time domain synchronization signal processing module carries out repetition and splicing processing on the time domain synchronization signals to obtain time domain beacon signals. Through the utilization of the method and the apparatus for beacon signal generation in the communication system of the invention, a signal peak average power ratio in the communication system can be reduced and the communication quality can be improved.

Description

Generation method and the device of beacon signal in communication system

Technical field

The present invention relates to communications processing field, relate in particular to the generation method and apparatus of the beacon signal in a kind of communication system.

Background technology

In Modern Communication System, the peak-to-average power ratio of signal of communication (PAPR, Peak to Average Power Ratio) refers to the power of signal peak and the ratio of average power.Peak-to-average power ratio is an important factor that affects communication quality.

Especially; based on Multicarrier Transmission Technology; as OFDM (OFDM; Orthogonal Frequency Division Multiplexing) technology; communication system in; conventionally can there is higher peak-to-average power ratio, thereby the efficiency of communication system and quality have been caused to larger impact.

For example orthogonal frequency division multiplexi obtains applying more and more widely in audio droadcasting system at present, but a major defect based on orthogonal FDM communication system is height power ratio, system output signal power fluctuation scope is very large, this requires the parts such as power amplifier in system, digital to analog converter to have enough large dynamic range, otherwise will inevitably cause the poor efficiency of these parts; Once the dynamic range of these parts can not reach requirement, can cause the clipping distortion of transmitted signal simultaneously, system communication quality declines.Therefore, the inhibition of the peak-to-average power ratio in communication system is absolutely necessary.

Beacon signal is an indispensable part in digital communication system in as the physical layer frame structure of digital audio broadcasting signal, and it refers to segment signal when each subframe is initial, can auxiliary receiver deadline and Frequency Synchronization fast and effectively.In communication system, conventionally will after the signal insertion beacon signal to be sent after modulation, form logical frame, logical frame forms physical layer signal frame again after sub-frame allocation, then launches to rf conversion through base band.

Current communication system, in China Mobile multimedia broadcasting (CMMB) system, what the frequency domain synchronizing sequence in the beacon signal generation method of using mainly adopted is straight binary pseudorandom PN sequence, generator polynomial is x ¹¹+ x ⁹+ 1.But this beacon signal is still more weak to the inhibitory action of the peak-to-average power ratio in communication system, cause signal peak-to-average power power ratio higher, communication quality is lower.

Summary of the invention

In view of this, main purpose of the present invention is to provide generation method and the device of beacon signal in a kind of communication system, to reduce the signal peak-to-average power power ratio in communication system, improves communication quality.

Technical scheme of the present invention is achieved in that

In the generation method of beacon signal, the method comprises:

According to the transmission mode of communication system, generating length is L * N _ifrequency domain synchronizing signal, N wherein _ifor the shared subband number of spectrum mode that signal to be sent adopts, L is effective subcarrier number of carrying on each subband of beacon signal;

Described frequency domain synchronizing signal is carried out to subcarrier mapping;

Frequency domain symbol after described subcarrier mapping is carried out to inverse Fourier transform and obtain Domain Synchronous signal;

Domain Synchronous signal is carried out to repetition and splices to process obtain time domain beacon signal.

Preferably, the described generation of the transmission mode according to communication system length is L * N _ithe concrete grammar of frequency domain synchronizing signal be:

The transmission mode adopting according to communication system, (1) generation length is L * N according to the following equation _ifrequency domain synchronizing signal:

$P_b\left(n\right)=\exp [-j{(-1)}^{\mathrm{<figure-callout\; id="2"\; label="n"\; filenames="HDA00001988613700021.png"\; state="\{\{state\}\}">n</figure-callout>}}2\mathrm{\&pi;q}\frac{n(n+1)2}{\mathrm{Nzc}}]---\left(1\right)$

N=0 in described formula (1), 1 ..., L * N _i-1, Mzc is the parameter relevant to described transmission mode with q.

Preferably, described communication system is digital audio broadcast system, the first transmission mode that described transmission mode is digital audio broadcast system and the 3rd transmission mode, described Nzc=967, described q=48, described L=120.

Preferably, described communication system is digital audio broadcast system, the second transmission mode that described transmission mode is digital audio broadcast system, described Nzc=487, described q=12, described L=60.

Preferably, described frequency domain synchronizing signal is carried out to subcarrier mapping, specifically comprises:

The spectrum mode index information using according to communication system finds current all effective subbands position, by described length, is L * N _ifrequency domain synchronizing signal be filled into successively from left to right on effective sub-carrier indices position of Domain Synchronous signal, wherein the 1st element is filled on effective subcarrier of Domain Synchronous channel distortion experienced index minimum, wherein virtual subnet carrier wave is filled to 0, thereby obtains the frequency domain symbol after subcarrier mapping.

Preferably, describedly frequency domain symbol after the mapping of described subcarrier carried out to inverse Fourier transform obtain Domain Synchronous signal, specifically comprise:

Frequency domain symbol X after utilizing following formula (2) to described subcarrier mapping _bcarry out inverse Fourier transform and obtain Domain Synchronous signal S _b(t):

$S_b\left(t\right)=\frac{1}{N_b}\underset{i=-N_b/2}{\overset{N_b/2-1}{\mathrm{\&Sigma;}}}{X}_b\left(i\right){\mathrm{<figure-callout\; id="2"\; label="e\; j"\; filenames="HDA00001988613700021.png"\; state="\{\{state\}\}">e</figure-callout>}}^j,0\&le;t\&le;T_b---\left(\text{2}\right)$

In above-mentioned formula (2), described N _bfor the total subcarrier number of Domain Synchronous signal, described X _b(i) be i subcarrier of Domain Synchronous signal, described (Δ f) _bfor the subcarrier spacing of Domain Synchronous signal, described T _btime span for Domain Synchronous signal.

Preferably, describedly Domain Synchronous signal is carried out to repetition and splicing process and to obtain time domain beacon signal, specifically comprise:

Described Domain Synchronous signal is repeated to twice, at the front end of the Domain Synchronous signal of these two repetitions, add Cyclic Prefix as protection, obtain time domain beacon signal.

A generating apparatus for beacon signal in communication system, this device comprises:

Frequency domain synchronizing signal generation module is L * N for generating length according to the transmission mode of communication system _ifrequency domain synchronizing signal, N wherein _ifor the shared subband number of spectrum mode that signal to be sent adopts, L is effective subcarrier number of carrying on each subband of beacon signal;

Mapping block, for carrying out subcarrier mapping to described frequency domain synchronizing signal;

Inverse Fourier transform module, obtains Domain Synchronous signal for the frequency domain symbol after described subcarrier mapping is carried out to inverse Fourier transform;

Domain Synchronous signal processing module, obtains time domain beacon signal for described Domain Synchronous signal being carried out to repetition and splicing to process.

Preferably, described frequency domain synchronizing signal generation module specifically for:

The transmission mode adopting according to communication system, (1) generation length is L * N according to the following equation _ifrequency domain synchronizing signal:

$P_b\left(n\right)=\exp [-j{(-1)}^{\mathrm{<figure-callout\; id="2"\; label="n"\; filenames="HDA00001988613700021.png"\; state="\{\{state\}\}">n</figure-callout>}}2\mathrm{\&pi;q}\frac{n(n+1)2}{\mathrm{Nzc}}]---\left(1\right)$

N=0 in described formula (1), 1 ..., L * N _i-1, Nzc is the parameter relevant to described transmission mode with q.

Preferably, described communication system is digital audio broadcast system;

When described transmission mode first transmission mode that is digital audio broadcast system and the 3rd transmission mode, described Nzc=967, described q=48, described L=120;

When the second transmission mode that described transmission mode is digital audio broadcast system, described Nzc=487, described q=12, described L=60.

Compared with prior art, the present invention is L * N according to the transmission mode generation length of communication system _ispecial frequency domain synchronizing signal, afterwards described frequency domain synchronizing signal is carried out to subcarrier mapping, again the frequency domain symbol after described subcarrier mapping is carried out to inverse Fourier transform and obtain Domain Synchronous signal, finally Domain Synchronous signal is carried out to repetition and splice to process obtaining time domain beacon signal.The present invention can adjust the generation parameter of described frequency domain synchronizing signal according to different transmission modes, thereby can effectively reduce the peak-to-average power ratio of signal, reduce the requirement of transmitted signal to parts such as the power amplifier in communication system, digital to analog converters, thereby improve the communication quality of communication system.

Accompanying drawing explanation

Fig. 1 is a kind of flow chart of the generation method of beacon signal in communication system of the present invention;

Fig. 2 is the physical layer frame structure figure in OFDM digital audio broadcast system;

Fig. 3 is a kind of composition and the position view in communication system thereof of the generating apparatus of beacon signal in communication system of the present invention;

Fig. 4 is a kind of schematic diagram of frequency domain synchronizing signal subcarrier mapping;

Fig. 5 is the structural representation of the time domain beacon signal that generates of the present invention;

Fig. 6 is the assist in synchronization FB(flow block) of the beacon signal of a kind of receiver based on the present invention's generation.

Embodiment

Below in conjunction with drawings and the specific embodiments, the present invention is further described in more detail.

Fig. 1 is a kind of flow chart of the generation method of beacon signal in communication system of the present invention.Referring to Fig. 1, the method comprises:

101, according to the transmission mode of communication system, generating length is L * N _ifrequency domain synchronizing signal, N wherein _ifor the shared subband number of spectrum mode that signal to be sent adopts, L is effective subcarrier number of carrying on each subband of beacon signal, and this L is the parameter relevant to transmission mode.

102, described frequency domain synchronizing signal is carried out to subcarrier mapping; Be about on effective subcarrier that described frequency domain synchronizing signal is mapped to Domain Synchronous signal.

103, the frequency domain symbol after described subcarrier mapping is carried out to inverse Fourier transform and obtain Domain Synchronous signal.

104, Domain Synchronous signal is carried out to repetition and splices processing obtaining time domain beacon signal.

The applicable communication system of the present invention can be that any employing beacon signal is carried out synchronous communication system, include, but are not limited to: the audio droadcasting system that adopts OFDM, adopt the digit broadcasting systems such as DVB-T, DRM, HD-Radio and CMMB of OFDM, asymmetrical Digital Subscriber Loop (ADSL) communication system, the digital audio broadcasting of etsi standard (DAB) system, high definition TV (HDTV) broadcast system, wireless lan (wlan) communication system, and the communication system of the Multicarrier Transmission Technology of other non-OFDM etc.

In embodiments of the invention, take OFDM digital audio broadcast system as example, the generation method of beacon signal is wherein described.

Fig. 2 is the physical layer frame structure figure in OFDM digital audio broadcast system.Referring to Fig. 2, each physical layer signal frame comprises the subframe that 4 length are 160ms, and each subframe comprises 1 beacon (being beacon signal, referred to as beacon) and S _nindividual OFDM symbol.The data of a logical frame of each physical layer signal frame carrying.Described beacon signal is an indispensable part in digital communication system in as the physical layer frame structure of digital audio broadcasting signal, and it refers to segment signal when each subframe is initial, can auxiliary receiver deadline and Frequency Synchronization fast and effectively.In logical frame framing procedure, first need to generate beacon signal.

Fig. 3 is a kind of composition and the position view in communication system thereof of the generating apparatus of beacon signal in communication system of the present invention.Referring to Fig. 3, the generating apparatus 300 of this beacon signal comprises:

Frequency domain synchronizing signal generation module 301, for carrying out the step 101 of described method, according to the transmission mode of communication system, generating length is L * N _ifrequency domain synchronizing signal, N wherein _ifor the shared subband number of spectrum mode that signal to be sent adopts, L is effective subcarrier number of carrying on each subband of beacon signal, and this L is the parameter relevant to transmission mode.

Mapping block 302, for carrying out the step 102 of described method, the frequency domain synchronizing signal described frequency domain synchronizing signal generation module 301 being generated is carried out subcarrier mapping.

Inverse Fourier transform module 303, for carrying out the step 103 of described method, is about to frequency domain symbol after described mapping block 302 subcarriers mappings and carries out inverse Fourier transform and obtain Domain Synchronous signal.

Domain Synchronous signal processing module 304, for carrying out the step 104 of described method, is about to described Domain Synchronous signal and carries out repetition and splice to process obtaining time domain beacon signal.This time domain beacon signal is exactly the beacon signal that the present invention need to generate.

Described OFDM data modulation module 305 is modulated into OFDM symbol by signal of communication to be sent exactly.The described time domain beacon signal of described Domain Synchronous signal processing module 304 outputs will be inserted into the front end of described OFDM symbol, thereby formation subframe, subframe forms physical layer signal frame again after sub-frame allocation, then to rf conversion, carries out radio-frequency transmissions through base band.

Introduce in detail in described beacon signal generative process the concrete methods of realizing of each step below.

First, in step 101, the transmission mode adopting according to digital audio broadcast system, (1) generation length is L * N according to the following equation _ifrequency domain synchronizing signal:

$P_b\left(n\right)=\exp [-j{(-1)}^{\mathrm{<figure-callout\; id="2"\; label="n"\; filenames="HDA00001988613700021.png"\; state="\{\{state\}\}">n</figure-callout>}}2\mathrm{\&pi;q}\frac{n(n+1)2}{\mathrm{Nzc}}]---\left(1\right)$

N wherein _ifor the shared subband number of spectrum mode that signal to be sent adopts, L is effective subcarrier number of carrying on each subband of beacon signal; N=0 in described formula (1), 1 ..., L * N _i-1, Nzc is the parameter relevant to described transmission mode with q.

Introduce respectively above-mentioned each determination method for parameter below.

For L, need to determine according to transmission mode.Described transmission mode refers to the set of transformation parameter in communication system, as number of carriers, OFDM symbol lengths etc.For example, in digital audio broadcast system, can be divided into three kinds of transmission modes, wherein the first transmission mode is that transmission mode 1, the second transmission mode is that transmission mode 2, the three transmission modes are transmission mode 3, and the system parameters of every kind of transmission mode is as shown in table 1 below:

Table 1

In the present invention, determine described L, first need to determine presently used transmission mode, then determine L according to the value of L and the relation of transmission mode that are described in table 2 below:

Transmission mode 1	Transmission mode 2	Transmission mode 3
			?120	?60	?120

Table 2

That is: current use transmission mode 1 and 3 o'clock, L=120; During current use transmission mode 2, L=60.

For N _i, for signal to be sent adopts the shared subband number of spectrum mode, the spectrum mode that therefore need to adopt according to current demand signal is determined.In OFDM digital audio broadcast system, the nominal bandwidth of digital audio broadcasting subband is 100kHz, for a kind of of digital audio broadcasting signal frequency spectrum cut apart.The subband that digital audio broadcasting signal is 100kHz by maximum 8 nominal bandwidth forms.If following table 3 is the spectrum mode of digital audio broadcasting signal permission use and the correspondence table of subband position, wherein in spectrum mode, the piece of white represents the frequency spectrum not taking, diagonal line hatches piece represents second subband of an effective subband, horizontal line shaded block represents the frequency band that simulation table takies, and the every pair of diagonal line hatches piece and vertical line shaded block form a subband.Digital audio broadcasting signal has defined two class spectrum modes, i.e. category-A spectrum mode and category-B spectrum mode.Wherein each subband nominal frequency of category-A spectrum mode is ± (i * 100+50) kHz, i=0, in 1,2,3(A class spectrum mode, red part is the reserved frequency band of analog broadcast signal); The integral multiple that each subband nominal frequency of category-B spectrum mode is 100kHz, ± i*100kHz, i=0,1,2,3.Different spectrum modes provides different bandwidth combination and the compatibility to existing analog broadcast signal.

Spectrum mode, its corresponding spectrum mode index and corresponding N in table 3, have been listed _ivalue.The spectrum mode that NI value described in above-mentioned formula (1) can adopt according to signal to be sent obtains to searching in table 3.

Table 3

For Nzc and the q in described formula (1), also need to determine according to current transmission mode.The transmission mode 1 of digital audio broadcasting signal and 3 o'clock, Nzc=967, q=48, Nzc=487 when transmission mode 2, q=12.In the present invention, by combination is concrete, apply required Parameter N zc, and choose suitable parameter q, can be so that this frequency domain sequence obtaining through formula (1) has very low peak-to-average power ratio at the time-domain signal through obtaining after being fourier transformed into time domain.

Next, in described step 102, by described frequency domain synchronizing signal P _b(n) be mapped on effective subcarrier of Domain Synchronous signal.Specifically comprise: the spectrum mode index information using according to digital audio broadcasting signal, described table 3, finds current all effective subbands position; Then contrast as following table 41 and table 42 by length, be L * N _ifrequency domain synchronizing sequence P _b(n) be filled into successively from left to right on effective sub-carrier indices position of Domain Synchronous signal, the 1st element is filled on effective subcarrier of Domain Synchronous channel distortion experienced index minimum, and wherein virtual subnet carrier wave is filled to 0, thereby obtains frequency domain symbol X _b.For example Fig. 4 is a kind of schematic diagram of frequency domain synchronizing signal subcarrier mapping.In this Fig. 4, be with spectrum mode index 1, the frequency domain synchronizing signal subcarrier mapping signal that transmission mode 1 is example.

Following table 41 is the sub-carrier indices table of category-B spectrum mode synchronizing signal, and table 42 is the sub-carrier indices table of Table A class spectrum mode synchronizing signal.

Table 41

Table 42

Next, in step 103, specifically comprise: the frequency domain symbol X after utilizing following formula (2) to described subcarrier mapping _bcarry out inverse Fourier transform and obtain Domain Synchronous signal S _b(t):

$S_b\left(t\right)=\frac{1}{N_b}\underset{i=-N_b/2}{\overset{N_b/2-1}{\mathrm{\&Sigma;}}}{X}_b\left(i\right)e^{\mathrm{<figure-callout\; id="2"\; label="j"\; filenames="HDA00001988613700021.png"\; state="\{\{state\}\}">j</figure-callout>}2\mathrm{\&pi;i}{\left(\mathrm{\&Delta;f}\right)}_{b}t},0\&le;t\&le;T_b---\left(\text{2}\right)$

In above-mentioned formula (2), described N _bfor the total subcarrier number of Domain Synchronous signal, described X _b(i) be i subcarrier of Domain Synchronous signal, described (Δ f) _bfor the subcarrier spacing of Domain Synchronous signal, described T _btime span for Domain Synchronous signal.

Wherein, described T _b, N _b(Δ f) _bconcrete value relevant with transmission mode, the relation of its concrete value and transmission mode, as following table 5, can inquire according to current transmission mode the value of described parameter from following table 5.

Parameter	Transmission mode	1	Transmission mode 2	Transmission mode 3
					T b（ms）	1.255（1024T）	?0.627（512T）	1.255（1024T）
N b	1024	?512	1024
				(Δf) b(Hz)	796.875	?1593.75	796.875

Table 5

Finally, in step 104, described by Domain Synchronous signal S _b(t) carry out repetition and splice processing obtaining time domain beacon signal.If Fig. 5 is the structural representation of time domain beacon signal.Referring to Fig. 5, this step 105 specifically comprises: by described Domain Synchronous signal S _b(t) repeat twice, at the Domain Synchronous signal S of these two repetitions _b(t) front end adds Cyclic Prefix as protection, obtains time domain beacon signal.In Fig. 5, described T _bcpfor the length of Cyclic Prefix, T _ube the Domain Synchronous signal S of two repetitions _b(t) length, T _bentire length for final time domain beacon signal.

After generating described time domain beacon signal, as shown in Figures 2 and 3, described time domain beacon signal is inserted to the front end of the OFDM symbol to be sent that described OFDM data modulation module 305 is modulated into, thereby formation subframe, subframe forms physical layer signal frame again after sub-frame allocation, then to rf conversion, carries out radio-frequency transmissions through base band.

At the signal receiver end of communication system, need to utilize the time domain beacon signal that described transmitting terminal sends to carry out assist in synchronization.Fig. 6 is the assist in synchronization FB(flow block) of the beacon signal of a kind of receiver based on the present invention's generation.Specifically comprise:

First, receiver changes into baseband signal by radiofrequency signal;

Then, in step 601, two identical Domain Synchronous signal S that receiver utilizes the beacon signal of time domain described in digital audio broadcasting signal (as shown in Figure 5) to comprise _b(t) feature, the search that completes subframe head with synchronize, search out two identical Domain Synchronous signal S _b(t) being just judged to be is subframe head;

Then, in step 602, receiver is by Domain Synchronous signal S _b(t) carry out the frequency domain symbol X that Fourier transform recovers transmission _b;

Then, in step 603 and 604, from the frequency domain symbol X recovering _bin extract frequency domain synchronizing signal P _b(n) P that, utilizes generation method of the present invention to generate _b(n) thus the good auto-correlation that sequence has and their cross correlation complete the sampled point of Frequency Synchronization and digital audio broadcasting signal synchronously to be followed the tracks of;

Finally, carry out digital audio and video signals data demodulates, until complete receiving course.

The foregoing is only preferred embodiment of the present invention, in order to limit the present invention, within the spirit and principles in the present invention not all, any modification of making, be equal to replacement, improvement etc., within all should being included in the scope of protection of the invention.

Claims (10)

1. a generation method for beacon signal in communication system, is characterized in that, the method comprises:

According to the transmission mode of communication system, generating length is L * N _ifrequency domain synchronizing signal, N wherein _ifor the shared subband number of spectrum mode that signal to be sent adopts, L is effective subcarrier number of carrying on each subband of beacon signal;

Described frequency domain synchronizing signal is carried out to subcarrier mapping;

Frequency domain symbol after described subcarrier mapping is carried out to inverse Fourier transform and obtain Domain Synchronous signal;

Domain Synchronous signal is carried out to repetition and splices to process obtain time domain beacon signal.

2. method according to claim 1, is characterized in that, it is L * N that the described transmission mode according to communication system generates length _ithe concrete grammar of frequency domain synchronizing signal be:

The transmission mode adopting according to communication system, (1) generation length is L * N according to the following equation _ifrequency domain synchronizing signal:

$P_b\left(n\right)=\exp [-j{(-1)}^{n}2\mathrm{\&pi;q}\frac{n(n+1)2}{\mathrm{Nzc}}]---\left(1\right)$

N=0 in described formula (1), 1 ..., L * N _i-1, Nzc is the parameter relevant to described transmission mode with q.

3. method according to claim 2, is characterized in that, described communication system is digital audio broadcast system, described transmission mode is the first transmission mode and the 3rd transmission mode of digital audio broadcast system, described Nzc=967, described q=48, described L=120.

4. method according to claim 2, is characterized in that, described communication system is digital audio broadcast system, the second transmission mode that described transmission mode is digital audio broadcast system, described Nzc=487, described q=12, described L=60.

5. method according to claim 1, is characterized in that, described frequency domain synchronizing signal is carried out to subcarrier mapping, specifically comprises:

The spectrum mode index information using according to communication system finds current all effective subbands position, by described length, is L * N _ifrequency domain synchronizing signal be filled into successively from left to right on effective sub-carrier indices position of Domain Synchronous signal, wherein the 1st element is filled on effective subcarrier of Domain Synchronous channel distortion experienced index minimum, wherein virtual subnet carrier wave is filled to 0, thereby obtains the frequency domain symbol after subcarrier mapping.

6. method according to claim 1, is characterized in that, describedly frequency domain symbol after the mapping of described subcarrier is carried out to inverse Fourier transform obtains Domain Synchronous signal, specifically comprises:

Frequency domain symbol X after utilizing following formula (2) to described subcarrier mapping _bcarry out inverse Fourier transform and obtain Domain Synchronous signal S _b(t):

$S_b\left(t\right)=\frac{1}{N_b}\underset{i=-N_b/2}{\overset{N_b/2-1}{\mathrm{\&Sigma;}}}{X}_b\left(i\right)e^{j2\mathrm{\&pi;i}{\left(\mathrm{\&Delta;f}\right)}_{b}t},0\&le;t\&le;T_b---\left(\text{2}\right)$

In above-mentioned formula (2), described N _bfor the total subcarrier number of Domain Synchronous signal, described X _b(i) be i subcarrier of Domain Synchronous signal, described (Δ f) _bfor the subcarrier spacing of Domain Synchronous signal, described T _btime span for Domain Synchronous signal.

7. method according to claim 1, is characterized in that, describedly Domain Synchronous signal is carried out to repetition and splicing processes and to obtain time domain beacon signal, specifically comprises:

Described Domain Synchronous signal is repeated to twice, at the front end of the Domain Synchronous signal of these two repetitions, add Cyclic Prefix as protection, obtain time domain beacon signal.

8. a generating apparatus for beacon signal in communication system, is characterized in that, this device comprises:

Frequency domain synchronizing signal generation module is L * N for generating length according to the transmission mode of communication system _ifrequency domain synchronizing signal, N wherein _ifor the shared subband number of spectrum mode that signal to be sent adopts, L is effective subcarrier number of carrying on each subband of beacon signal;

Mapping block, for carrying out subcarrier mapping to described frequency domain synchronizing signal;

Inverse Fourier transform module, obtains Domain Synchronous signal for the frequency domain symbol after described subcarrier mapping is carried out to inverse Fourier transform;

Domain Synchronous signal processing module, obtains time domain beacon signal for described Domain Synchronous signal being carried out to repetition and splicing to process.

9. device according to claim 8, is characterized in that, described frequency domain synchronizing signal generation module specifically for:

The transmission mode adopting according to communication system, (1) generation length is L * N according to the following equation _ifrequency domain synchronizing signal:

$P_b\left(n\right)=\exp [-j{(-1)}^{n}2\mathrm{\&pi;q}\frac{n(n+1)2}{\mathrm{Nzc}}]---\left(1\right)$

N=0 in described formula (1), 1 ..., L * N _i-1, Nzc is the parameter relevant to described transmission mode with q.

10. device according to claim 9, is characterized in that, described communication system is digital audio broadcast system;

When described transmission mode first transmission mode that is digital audio broadcast system and the 3rd transmission mode, described Nzc=967, described q=48, described L=120;

When the second transmission mode that described transmission mode is digital audio broadcast system, described Nzc=487, described q=12, described L=60.

Images