CN106131672A - The method and system that Universal Terrestrial broadcast digital television signals pattern quickly identifies - Google Patents

Abstract

The invention discloses a kind of Universal Terrestrial broadcast digital television signals pattern and quickly know method for distinguishing, comprise the following steps: according to the feature of all types of signals, detection receives whether signal is ATSC signal respectively, single carrier DTMB signal, multicarrier DTMB signal and DVB signal, after traversal tests above signal type, it is impossible to determine the type of reception signal, then judge to receive in signal to there are not above-mentioned four kinds of ground digital television broadcast signals.The system that a kind of Universal Terrestrial broadcast digital television signals pattern quickly identifies, including: ATSC signal detection module, DTMB single-carrier signal detection module, DTMB multi-carrier signal detection module, DVB signal detection module.High efficiency can detect the pattern receiving signal；Additionally, due to the use of energy normalized, decision threshold is limited between 0 to 1, and the difficulty greatly reducing thresholding setting ensure that again the highest detection probability simultaneously.It is widely used in terrestrial DTV technical field.

Description

The method and system that Universal Terrestrial broadcast digital television signals pattern quickly identifies

Technical field

The present invention relates to terrestrial DTV technical field, be specifically related to global existing digital television ground broadcast signal Detection and recognition methods and system.

Background technology

Along with the development of terrestrial DTV technology, the highly desirable DTV of user can provide global broadcast to overflow Trip service, i.e. digital cable customers is in the case of using same terminal, the most somewhere can receive locality Digital television signal also enjoys local digital television service.Global broadcast roaming is possible not only to promote the region of broadcast, the whole nation And international coordination, facilitate operator to provide the user the audio/video program service of more convenient high-quality, meanwhile, in disaster and urgent feelings Under condition and the aspect such as navigation and safety, global broadcast roaming provides between system the probability of interconnection and interflow for information service. Universal Terrestrial digital TV broadcast standards specifically includes that North America ATSC, Europe DVB-T/DVB-T2 and China DTMB tri-kinds at present, In countries in the world popularization and application；Additionally, due to reasons such as political economy, there is two or more ground digital in some countries The situation that television standard system uses simultaneously.Therefore, the global roaming of receiver to be realized, first have to solve multiple ground digital The identification problem of television standard signal.

Summary of the invention

In order to solve above-mentioned technical problem, it is an object of the invention to according to global existing terrestrial broadcasting digital television standard The architectural feature of signal, proposes the method and system of a kind of quick identification terrestrial broadcasting digital television signal pattern.

The technical solution adopted in the present invention is:

The present invention provides a kind of Universal Terrestrial broadcast digital television signals pattern quickly to know method for distinguishing, including following step Rapid:

The docking collection of letters number is sampled, and chooses several signal sampling points as signal to be detected；

In synchronizing according to ATSC signal field, the autocorrelation detection of PN63 sequence receives whether signal is ATSC signal, is then Detection terminates, and otherwise carries out other types test；

Receive whether signal is single carrier DTMB letter according to distinctive PN595 Sequence Detection in single carrier DTMB signal frame head Number, it is that detection terminates, and otherwise carries out other types test；

Receive whether signal is many according to the autocorrelation detection of PN sequence in two kinds of frame head modes of multicarrier DTMB signal Carrier wave DTMB signal, is that detection terminates, and otherwise carries out other types test；

Receive whether signal is DVB signal according to distinctive Cyclic Prefix detection in DVB signal, be that detection terminates, no Then carry out other types test；

After traversal tests above signal type, it is impossible to determine the type of reception signal, then judge to receive in signal not deposit At above-mentioned three kinds of ground digital television broadcast signals.

As the improvement of this technical scheme, it further comprises the steps of:

Assume that receiving signal is a predefined type, carry out slip auto-correlation to measured signal, calculating sequence of correlation values:

Correlated series value is carried out energy normalized and obtains decision statistics；

Decision statistics is carried out segmentation, and calculates the maximum of every section；

Hypothesis testing level is set and determines decision threshold, compare the size of decision statistics every section maximum and decision threshold And the distance between adjacent maxima.

As the improvement of this technical scheme, described judgement includes:

If decision statistics is of substantially equal more than the distance between decision threshold, and adjacent maxima, it assumes that set up, Terminate to receive the type detection of signal；

Otherwise judge to receive the signal that signal is not assumed type, then carry out other kinds of detection.

As the improvement of this technical scheme, described step is according to the autocorrelation inspection of PN63 sequence in the synchronization of ATSC signal field Survey and receive whether signal is ATSC signal, comprising:

Carrying out time delay auto-correlation to measured signal, correlation length is 63*4, and correlation distance is 2*63*4；

Sequence of correlation values is carried out energy normalized, calculates decision statistics；

Decision statistics is carried out segmentation, and calculates the maximum of every section；

Whether decision statistics is more than the whether approximately equal of the interval between pre-determined threshold and adjacent maxima；

Being that detection terminates, receiving signal is ATSC signal；

Otherwise carry out other types test.

As the further improvement of this technical scheme, described step is according to distinctive in single carrier DTMB signal frame head PN595 Sequence Detection receives whether signal is single carrier DTMB signal, comprising:

The docking collection of letters number carries out time delay auto-correlation, and correlation length is 595*4, and correlation distance is (595+3780) * 4；

Sequence of correlation values is carried out energy normalized, calculates decision statistics；

Decision statistics is carried out segmentation, and calculates the maximum of every section；

Whether decision statistics is more than the whether approximately equal of the distance between pre-determined threshold and adjacent maxima；

Being that detection terminates, receiving signal is single carrier DTMB signal；

Otherwise carry out other types test.

As the further improvement of this technical scheme, described step is according to PN in two kinds of frame head modes of multicarrier DTMB signal The autocorrelation detection of sequence receives whether signal is multicarrier DTMB signal, comprising:

The docking collection of letters number carries out time delay auto-correlation, and correlation length is 82*4, and correlation distance is (255+82) * 4, calculates judgement Statistic；

Decision statistics is carried out segmentation, and calculates the maximum of every section；

Whether decision statistics is more than the whether approximately equal of the distance between pre-determined threshold and adjacent maxima；

It is that detection terminates, receives the multicarrier DTMB signal that signal is the first frame head mode；

Otherwise the docking collection of letters number carries out time delay auto-correlation, and correlation length is 511*4, and correlation distance is (511+217) * 4, meter Calculate decision statistics；

Decision statistics is carried out segmentation, and calculates the maximum of every section；

Whether decision statistics is more than the whether approximately equal of the distance between pre-determined threshold and adjacent maxima；

It is that detection terminates, receives the multicarrier DTMB signal that signal is the second frame head mode；

Otherwise carry out other types test.

As the further improvement of this technical scheme, described step connects according to distinctive Cyclic Prefix detection in DVB signal Whether the collection of letters number is DVB signal, comprising:

Carry out time delay auto-correlation to measured signal；

Sequence of correlation values is carried out energy normalized, calculates decision statistics；

Decision statistics is carried out segmentation, and calculates the maximum of every section；

Whether decision statistics is more than the whether approximately equal of the distance between pre-determined threshold and adjacent maxima；

Being that detection terminates, receiving signal is DVB signal；

Otherwise carry out other types test.

On the other hand, the present invention also provides for the system that a kind of Universal Terrestrial broadcast digital television signals pattern quickly identifies, Including:

ATSC signal detection module, in performing to synchronize according to ATSC signal field, the autocorrelation detection of PN63 sequence connects Whether the collection of letters number is ATSC signal, is, detection terminates；Otherwise carry out other types test；

DTMB single-carrier signal detection module, for performing according to distinctive PN595 sequence in single carrier DTMB signal frame head Row detection receives whether signal is single carrier DTMB signal, is, detection terminates, and otherwise carries out other types test；

DTMB multi-carrier signal detection module, for performing according to PN sequence in two kinds of frame head modes of multicarrier DTMB signal Autocorrelation detection receive signal whether be multicarrier DTMB signal, be, detection terminate, otherwise carry out other types test；

DVB signal detection module, for performing to receive signal according to distinctive Cyclic Prefix detection in DVB signal be whether DVB signal, is that detection terminates, and otherwise carries out other types test.

The invention has the beneficial effects as follows: the mode identification method of terrestrial broadcasting digital television signal that the present invention proposes and be System, make full use of the signal characteristic of various signal, due to the signal of several standards exist in terms of signal frame structure the poorest The opposite sex, therefore can receive the particular type of signal according to the architectural feature identification of signal.High efficiency can detect reception The pattern of signal；Additionally, due to the use of energy normalized, decision threshold is limited between 0 to 1, greatly reduces thresholding and sets The difficulty put ensure that again the highest detection probability simultaneously.

Accompanying drawing explanation

Below in conjunction with the accompanying drawings the detailed description of the invention of the present invention is described further:

Fig. 1 is the system model figure of an embodiment of ground digital television broadcast signal identifying schemes of the present invention；

Fig. 2 is the time delay auto-correlation schematic diagram of an embodiment of ground digital television broadcast signal identifying schemes of the present invention；

Fig. 3 is the overview flow chart of an embodiment of ground digital television broadcast signal identifying schemes of the present invention；

Fig. 4 is the flow process of the ATSC detection module of ground digital television broadcast signal identifying schemes one embodiment of the present invention Figure；

Fig. 5 is the detection single carrier DTMB signal of ground digital television broadcast signal identifying schemes one embodiment of the present invention Flow chart；

Fig. 6 is the detection multicarrier DTMB signal of ground digital television broadcast signal identifying schemes one embodiment of the present invention Flow chart；

Fig. 7 is the flow chart of the detection DVB signal of ground digital television broadcast signal identifying schemes one embodiment of the present invention.

Detailed description of the invention

It should be noted that in the case of not conflicting, the embodiment in the application and the feature in embodiment can phases Combination mutually.

The present invention provides a kind of multimode recognition method of terrestrial broadcasting digital television signal, utilizes various broadcast singal Signal characteristic solves multi-standard and the identification problem of multi-standard terrestrial broadcasting digital television signal.Implementation step is: (1) root In synchronizing according to ATSC signal field, the autocorrelation detection of PN63 sequence receives whether signal is ATSC signal；(2) according to single carrier In DTMB signal frame head, distinctive PN595 Sequence Detection receives whether signal is single carrier DTMB signal；(3) according to multicarrier In two kinds of frame head modes of DTMB signal, the autocorrelation detection of PN sequence receives whether signal is multicarrier DTMB signal；(4) root Receive whether signal is DVB signal according to distinctive Cyclic Prefix detection in DVB signal.The present invention utilizes the feature of various signal, Can quickly and accurately identify the pattern receiving signal, roam for the global broadcast of digital television receiver that provide can Energy.

The basic model figure of this programme is as it is shown in figure 1, mainly include that ATSC signal detection module, DTMB single-carrier signal are examined Survey module, DTMB multi-carrier signal detection module and DVB signal detection module.ATSC signal detection module utilizes in field synchronization two Individual adjacent PN63 sequence judges to receive signal whether as ATSC signal；DTMB single-carrier signal detection module utilizes the mono-load of DTMB PN595 sequence in ripple signal judges to receive signal whether as DTMB single-carrier signal；DTMB multi-carrier signal detection module profit With leading in DTMB multi-carrier signal frame head and after lead and judge to receive signal whether as DTMB multi-carrier signal；DVB signal Cyclic Prefix before detection module utilizes each OFDM symbol of DVB signal judges to receive signal whether as DVB signal.

The basic thought realizing the present invention is: utilize self unique signal node of several ground digital television broadcast signal Structure feature, carries out repeatedly auto-correlation computation and processes to obtain its corresponding signal mode testing result reception signal to be detected, As shown in Figure 2.The correlation length assuming auto-correlation computation is L_corr, correlation distance is D_corr, by L every in measured signal_corrNumber According to its time delay D_corrData after individual sampled point carry out conjugate multiplication and are added, and obtain a sequence of correlation values, if time delay D_corr L after individual sampled point_corrIndividual data and current L_corrIndividual data are identical, then sequence of correlation values will occur one substantially herein Energy peak, if utilizing this characteristic, as long as arranging suitable correlation length L_corr, correlation distance D_corrAnd decision threshold, so that it may To detect the particular type receiving signal.Every time detecting in this programme can be regarded as a binary hypothesis test:

H₀: receiving signal is the signal of current detection,

H₁: receive the signal that signal is not current detection,

Where it is assumed that H₀Acceptance region be Λ>η, region of rejection be Λ<η, Λ be final decision statistics, η for preset sentence Certainly thresholding.

This programme comprises the steps:

1, baseband receiving signals x (t) is carried out 4 samplings, it is thus achieved that x (n), n represent sampling number, then take M= 200000 signal sampling points, as signal to be detected, first determine whether to receive whether signal is ATSC signal；

(1) selected hypothesis H₀: receiving signal is ATSC signal, H₁: receiving signal is not ATSC signal；

(2) slip auto-correlation is carried out to measured signal, calculating sequence of correlation values R (n):

$R\left(n\right)=\underset{k=0}{\overset{L-1}{\&Sigma;}}x(n+k)\&CenterDot;x*(n+k+D),$

Wherein, L represents correlation length, and its value is the length of a PN63 sequence, i.e. L=63*4；D represents correlation distance, D The length that value is two PN63 sequences, i.e. D=2*63*4；x^*(n+k+D) expression takes conjugation to signal x (n+k+D)；

(3) correlated series value is carried out energy normalized and obtains decision statistics:

$J\left(n\right)=\frac{|R\left(n\right){|}^2}{{\left(\underset{k=0}{\overset{L-1}{\&Sigma;}}\right|x\left(n+k+D\right){|}^2)}^2},$

WhereinFor the energy of the measured signal in associated window, | | represent modulo operation；By J (n) point Section, every segment length is the length of a Frame, i.e. 313*828*4, calculates the maximum of every sectionAnd between adjacent maxima Distance；

(4) the horizontal 1-a of hypothesis testing is set, determines decision threshold λ according to 1-a according to formula as follows:

$\mathrm{\&lambda;}=(1-a)*\frac{1}{C}\underset{i=1}{\overset{C}{\&Sigma;}}{\hat{J}}_i$

Wherein, C represents the number of the correlation peak determining decision threshold needs, makes C=5,Represent i-th relevant peaks Value；

(5) size of decision statistics J (n) and λ is compared, if the distance between J (n) > λ, and adjacent two maximums Approximately equal, it assumes that H₀Set up, i.e. judges reception signal as ATSC signal, and credibility is 1-a, and detection terminates；Otherwise false If H₁Set up, i.e. judge that receiving signal is not ATSC signal, and credibility is 1-a, enters and detects next time；

2, judge to receive the DTMB signal whether signal is single carrier mode；

(1) selected hypothesis H₀: receive the DTMB signal that signal is single carrier mode, H₁: receiving signal is not single carrier mode DTMB signal；

(2) carry out slip auto-correlation to measured signal, calculate sequence of correlation values R₁(n):

$R_1\left(n\right)=\underset{k=0}{\overset{L_1-1}{\&Sigma;}}x(n+k)\&CenterDot;x^{*}(n+k+D_1),$

Wherein, L₁Representing correlation length, its value is the length of PN595 sequence, i.e. L₁=595*4；D₁Represent correlation distance, D₁The length that value is a DTMB signal frame, i.e. D₁=(595+3780) * 4；

(3) sequence of correlation values is carried out energy normalized, obtains decision statistics:

$J_1\left(n\right)=\frac{|R_1\left(n\right){|}^2}{{\left(\underset{k=0}{\overset{L_1-1}{\&Sigma;}}\right|x\left(n+k+D_1\right){|}^2)}^2},$

WhereinFor the energy of measured signal in associated window；By J₁N () segmentation, every segment length is one The length of Frame, i.e. (595+3780) * 4, calculate the correlation peak of every sectionAnd between adjacent two correlation peaks away from From；

(4) the horizontal 1-a of hypothesis testing is set, determines decision threshold λ according to 1-a according to equation below₁:

${\mathrm{\&lambda;}}_1=(1-a)*\frac{1}{C}\underset{i=1}{\overset{C}{\&Sigma;}}{\hat{J}}_{1i}$

Wherein, C represents the number of the correlation peak determining decision threshold needs, makes C=5,Represent i-th relevant peaks Value；

(5) decision statistics J is compared₁(n) and λ₁Size, if J₁(n)>λ₁, and between adjacent two correlation peaks Distance approximately equal, it assumes that H₀Set up, i.e. judge the DTMB signal receiving signal as single carrier mode, and credibility is 1-a, Detection terminates；Otherwise assume H₁Set up, i.e. judge to receive the DTMB signal that signal is not single carrier mode, and credibility is 1-a, Enter and detect next time；

3, judging to receive the DTMB signal whether signal is multi-carrier mode, the DTMB signal of multicarrier includes two kinds of frame heads Pattern, therefore need twice detection to complete；

(1) judge to receive the multicarrier DTMB signal whether signal is the first frame head mode；

1a) selected hypothesis H₀: receive the multicarrier DTMB signal that signal is the first frame head mode, H₁: receiving signal is not The multicarrier DTMB signal of the first frame head mode；

1b) carry out slip auto-correlation to measured signal, calculate sequence of correlation values R₂(n):

$R_2\left(n\right)=\underset{k=0}{\overset{L_2-1}{\&Sigma;}}x(n+k)\&CenterDot;x^{*}(n+k+D_2),$

Wherein, L₂For correlation length, its value is equal to the length of leading symbol, i.e. 82*4, D in PN420 sequence₂For relevant away from From, its value is the leading length sum with PN255 sequence, i.e. (255+82) * 4 equal in PN420 sequence；

1c) correlated series value is carried out energy normalized and obtains decision statistics:

$J_2\left(n\right)=\frac{|R_2\left(n\right){|}^2}{{\left(\underset{k=0}{\overset{L_2-1}{\&Sigma;}}\right|x\left(n+k+D_2\right){|}^2)}^2},$

WhereinEnergy for the measured signal in associated window；By J₂N () segmentation, every segment length is one The length of Frame, i.e. (420+3780) * 4, calculate the correlation peak of every sectionAnd between adjacent two correlation peaks away from From；

Hypothesis testing horizontal 1-a 1d) is set, is determined decision threshold λ according to 1-a by equation below₂:

${\mathrm{\&lambda;}}_2=(1-a)*\frac{1}{C}\underset{i=1}{\overset{C}{\&Sigma;}}{\hat{J}}_{2i}$

Wherein, C represents the number of the correlation peak determining decision threshold needs, makes C=5,Represent i-th relevant peaks Value；

1e) compare decision statistics J₂(n) and λ₂Size, if J₂(n)>λ₂, and between adjacent two correlation peaks Distance approximately equal, it assumes that H₀Set up, i.e. judge the multicarrier DTMB signal receiving signal as the first frame head mode, and can Reliability is 1-a, and detection terminates；Otherwise assume H₁Set up, i.e. judge to receive the multicarrier that signal is not the first frame head mode DTMB signal, and credibility is 1-a, enters and detects next time；

(2) judge to receive the multicarrier DTMB signal whether signal is the second frame head mode；

2a) selected hypothesis H₀: receive the multicarrier DTMB signal that signal is the second frame head mode, H₁: receiving signal is not The multicarrier DTMB signal of the second frame head mode；

2b) carry out slip auto-correlation to measured signal, calculate sequence of correlation values R₃(n):

$R_3\left(n\right)=\underset{k=0}{\overset{L_3-1}{\&Sigma;}}x(n+k)\&CenterDot;x*(n+k+D_3),$

Wherein, L₃For correlation length, its value is equal to the length of leading part, i.e. 217*4, D in PN945 sequence₃For relevant away from From, its value is equal to the length sum of leading part in PN945 sequence with PN511 sequence, i.e. (217+511) * 4；

2c) correlated series value is carried out energy normalized and obtains decision statistics:

$J_3\left(n\right)=\frac{|R_3\left(n\right){|}^2}{{\left(\underset{k=0}{\overset{L_3-1}{\&Sigma;}}\right|x\left(n+k+D_3\right){|}^2)}^2},$

WhereinEnergy for the measured signal in associated window；By J₃N () segmentation, every segment length is one The length of Frame, i.e. (945+3780) * 4, calculate the correlation peak of every sectionAnd between adjacent two correlation peaks away from From；

Hypothesis testing horizontal 1-a 2d) is set, is determined decision threshold λ according to 1-a by equation below₃:

${\mathrm{\&lambda;}}_3=(1-a)*\frac{1}{C}\underset{i=1}{\overset{C}{\&Sigma;}}{\hat{J}}_{3i}$

Wherein, C represents the number of the correlation peak determining decision threshold needs, makes C=5,Represent i-th relevant peaks Value；

2e) compare decision statistics J₃(n) and λ₃Size, if J₃(n)>λ₃, and between adjacent two correlation peaks Distance approximately equal, it assumes that H₀Set up, i.e. judge the multicarrier DTMB signal receiving signal as two kinds of frame head modes, and credible Degree is 1-a, and detection terminates；Otherwise assume H₁Set up, i.e. judge to receive the multicarrier DTMB that signal is not the second frame head mode Signal, and credibility is 1-a, enters and detects next time；

4, judge to receive whether signal is DVB signal；The subcarrier pattern of DVB signal support have 1K, 2K, 4K, 8K, 16K, And 32K, and often sub-carrier all may comprise the protection interval of 1/128,1/32,1/16,19/256,1/8,19/128,1/4, So in order to improve detection efficiency, this method is provided with the autocorrelative correlation length of suitable time delay, utilizes single treatment Detect all possible DVB signal type under every sub-carrier pattern, specifically comprise the following steps that

(1) selected hypothesis H₀: receive signal be sub-carrier number be that (value of N is 1024,2048,4096,8192,16384 to N Or 32768) DVB signal, H₁: receive signal be not sub-carrier number be the DVB signal of N；

(2) carry out slip auto-correlation to measured signal, calculate sequence of correlation values R'(n):

$R^{\&prime;}\left(n\right)=\underset{k=0}{\overset{L^{\&prime;}-1}{\&Sigma;}}x(n+k)\&CenterDot;x^{*}(n+k+D^{\&prime;})$

Wherein, L' is correlation length, and its value is protection interval minimum under different sub carrier pattern, and D' is correlation distance, Its value equal to OFDM symbol at sampling number corresponding to time domain, under concrete value such as table 1 each subcarrier pattern of L' and D' Shown in the value of correlation length L' and correlation distance D'；

Table 1

(3) correlated series value is carried out energy normalized and obtains decision statistics:

$J^{\&prime;}\left(n\right)=\frac{|R^{\&prime;}\left(n\right){|}^2}{{\left(\underset{k=0}{\overset{L^{\&prime;}-1}{\&Sigma;}}\right|x\left(n+k+D^{\&prime;}\right){|}^2)}^2}$

WhereinEnergy for the measured signal in associated window；By J'(n) segmentation, every segment length is approximately The length of one Frame, i.e. L'+D', calculate the correlation peak of every section

(4) the horizontal 1-a of hypothesis testing is set, is determined decision threshold λ ' according to 1-a by below equation:

${\mathrm{\&lambda;}}^{,}=(1-a)*\frac{1}{C}\underset{i=1}{\overset{C}{\&Sigma;}}{\hat{J}}_i^{,}$

Wherein, C represents the number of the correlation peak determining decision threshold needs, makes C=5,Represent i-th relevant peaks Value；

(5) compare decision statistics J'(n) and the size of λ ', if J'(n) > between λ ', and adjacent correlation peak away from From approximately equal, it assumes that H₀Set up, i.e. judges to receive signal as sub-carrier number as the DVB signal of N, and credibility is 1-a, examines Survey terminates；Otherwise assume H₁Set up, i.e. judge that receiving signal is not the sub-carrier number DVB signal as N, and credibility is 1-a, enters Enter and detect next time.

More than detect after all terminating, if judging to receive the type of signal not yet, then it is assumed that receive in signal and do not exist Three kinds of ground digital television broadcast signals to be detected.

With reference to Fig. 3, it it is the overview flow chart of an embodiment of ground digital television broadcast signal identifying schemes of the present invention.Its The docking collection of letters number is sampled, and chooses several signal sampling points as signal to be detected；

In synchronizing according to ATSC signal field, the autocorrelation detection of PN63 sequence receives whether signal is ATSC signal；It is, Then detection terminates；Not, then other types test is carried out；

Receive whether signal is single carrier DTMB letter according to distinctive PN595 Sequence Detection in single carrier DTMB signal frame head Number；It is that then detection terminates；Not, then other types test is carried out；

Receive whether signal is many according to the autocorrelation detection of PN sequence in two kinds of frame head modes of multicarrier DTMB signal Carrier wave DTMB signal；It is that then detection terminates；Not, then other types test is carried out；

Receive whether signal is DVB signal according to distinctive Cyclic Prefix detection in DVB signal；It is that then detection terminates；No It is then to carry out other types test；

After traversal tests above signal type, it is impossible to determine the type of reception signal, then judge to receive in signal not deposit At above-mentioned four kinds of ground digital television broadcast signals.

With reference to modules flow chart as also shown in e.g. figs. 4-7, the present invention to implement step as follows:

1. pair baseband receiving signals x (t) carries out 4 samplings, it is thus achieved that x (n), then takes M=200000 signal sampling point As signal to be detected, first receive whether signal is ATSC signal according to ATSC signal distinctive PN63 Sequence Detection；Docking The collection of letters number carries out sliding and is correlated with, calculating correlated series value R (n):

$R\left(n\right)=\underset{k=0}{\overset{L-1}{\&Sigma;}}x(n+k)\&CenterDot;x*(n+k+D),$

Wherein, L represents correlation length, and its value is the length of a PN63 sequence, i.e. L=63*4；D represents correlation distance, D The length that value is two PN63 sequences, i.e. D=2*63*4x^*(n+k+D) expression takes conjugation to signal x (n+k+D)；

Then calculating decision statistics J (n):

$J\left(n\right)=\frac{|R\left(n\right){|}^2}{{\left(\underset{k=0}{\overset{L-1}{\&Sigma;}}\right|x\left(n+k+D\right){|}^2)}^2},$

WhereinEnergy for the measured signal in associated window；By decision statistics segmentation, and count Calculate the maximum of every section；The horizontal 1-a of hypothesis testing is set, calculates decision threshold, decision statistics J (n) is entered with pre-determined threshold λ Row compares, if decision statistics is more than the distance approximately equal between pre-determined threshold, and adjacent maxima, then judges to receive letter Number it is ATSC signal, and the credibility of this hypothesis is 1-a；Otherwise receiving signal is not ATSC signal, detects next time；

2. detection receives the DTMB signal whether signal is single carrier mode, carries out slip auto-correlation to measured signal, meter Calculate sequence of correlation values R₁(n):

$R_1\left(n\right)=\underset{k=0}{\overset{L_1-1}{\&Sigma;}}x(n+k)\&CenterDot;x^{*}(n+k+D_1),$

Wherein, L₁Representing correlation length, its value is the length of PN595 sequence, i.e. L₁=595*4；D₁Represent correlation distance, D₁The length that value is a DTMB signal frame (frame head+frame), i.e. D₁=(595+3780) * 4；Sequence of correlation values is carried out Energy normalized, obtains decision statistics:

$J_1\left(n\right)=\frac{|R_1\left(n\right){|}^2}{{\left(\underset{k=0}{\overset{L_1-1}{\&Sigma;}}\right|x\left(n+k+D_1\right){|}^2)}^2},$

WhereinFor the energy of measured signal in associated window；Decision statistics is carried out segmentation, and Calculate the maximum of every section；Relatively decision statistics and pre-determined threshold, if existed more than pre-determined threshold in decision statistics Value, and the distance approximately equal between adjacent maxima, then receive the DTMB signal that signal is single carrier mode, otherwise receive letter Number it not the DTMB signal of single carrier, continue detection and receive the DTMB signal whether signal is multicarrier；

3. detection receives the multicarrier DTMB signal whether signal is the first frame head mode, and docking is collected mail and number slided Auto-correlation, calculates sequence of correlation values R₂(n):

$R_2\left(n\right)=\underset{k=0}{\overset{L_2-1}{\&Sigma;}}x(n+k)\&CenterDot;x^{*}(n+k+D_2),$

Wherein, L₂For correlation length, take the length of leading symbol, i.e. L in PN420 sequence here₂=82*4, D₂It is relevant Distance, its value is the leading length sum with PN255 sequence, i.e. D equal in PN420 sequence₂=(255+82) * 4；To correlated series Value carries out energy normalized and obtains decision statistics:

$J_2\left(n\right)=\frac{|R_2\left(n\right){|}^2}{{\left(\underset{k=0}{\overset{L_2-1}{\&Sigma;}}\right|x\left(n+k+D_2\right){|}^2)}^2},$

Decision statistics is carried out segmentation, and the maximum in calculating every section；Decision statistics is carried out with pre-determined threshold Relatively, if decision statistics exists the value more than pre-determined threshold, and the distance approximately equal between adjacent maxima, then recognize For receiving the multicarrier DTMB signal that signal is the first frame head mode, otherwise continue detection and receive whether signal is DTMB letter Number；

4. detection receives the multicarrier DTMB signal whether signal is the second frame head mode；The docking collection of letters number is slided Auto-correlation, calculates sequence of correlation values R₃(n):

$R_3\left(n\right)=\underset{k=0}{\overset{L_3-1}{\&Sigma;}}x(n+k)\&CenterDot;x^{*}(n+k+D_3),$

Wherein, L₃For correlation length, its value is equal to the length of leading part, i.e. 217*4, D in PN945 sequence₃For relevant away from From, its value is equal to the length sum of leading part in PN945 sequence with PN511 sequence, i.e. (217+511) * 4, by correlated series Decision statistics can be obtained with the energy receiving signal

$J_3\left(n\right)=\frac{|R_3\left(n\right){|}^2}{{\left(\underset{k=0}{\overset{L_3-1}{\&Sigma;}}\right|x\left(n+k+D_3\right){|}^2)}^2},$

Decision statistics is carried out segmentation, and the maximum in calculating every section；Decision statistics is carried out with pre-determined threshold Relatively, if decision statistics exists the value more than pre-determined threshold, and the distance approximately equal between adjacent maxima, then recognize For receiving the multicarrier DTMB signal that signal is the second frame head mode, otherwise enter and detect next time；

5. detection receives whether signal is DVB signal.Signal to be detected is carried out slip auto-correlation, calculates correlated series value R'(n):

$R^{\&prime;}\left(n\right)=\underset{k=0}{\overset{L^{\&prime;}-1}{\&Sigma;}}x(n+k)\&CenterDot;x^{*}(n+k+D^{\&prime;})$

Wherein, L' is correlation length, and D' is correlation distance, and its value is as shown in table 1, correlated series and signal energy obtain To decision statistics:

$J^{\&prime;}\left(n\right)=\frac{|R^{\&prime;}\left(n\right){|}^2}{{\left(\underset{k=0}{\overset{L^{\&prime;}-1}{\&Sigma;}}\right|x\left(n+k+D^{\&prime;}\right){|}^2)}^2}$

Decision statistics is carried out segmentation, and the maximum in calculating every section；Decision statistics is carried out with pre-determined threshold Relatively, if decision statistics exists the value more than pre-determined threshold, and the distance approximately equal between adjacent maxima, then recognize It is DVB signal for receiving signal, otherwise enters and detect next time；

6. detecting more than after all terminating, if not determining the type receiving signal yet, then judging reception signal does not exists Three kinds of ground digital television broadcast signals.

It is above the preferably enforcement of the present invention is illustrated, but the invention is not limited to described enforcement Example, those of ordinary skill in the art also can make all equivalent variations on the premise of spirit of the present invention or replace Changing, deformation or the replacement of these equivalents are all contained in the application claim limited range.

Claims (8)

1. a Universal Terrestrial broadcast digital television signals pattern quickly knows method for distinguishing, it is characterised in that comprise the following steps:

The docking collection of letters number is sampled, and chooses several signal sampling points as signal to be detected；

In synchronizing according to ATSC signal field, the autocorrelation detection of PN63 sequence receives whether signal is ATSC signal, is to detect Terminate, otherwise carry out other types test；

Receive whether signal is single carrier DTMB signal according to distinctive PN595 Sequence Detection in single carrier DTMB signal frame head, It is that detection terminates, and otherwise carries out other types test；

Receive whether signal is multicarrier according to the autocorrelation detection of PN sequence in two kinds of frame head modes of multicarrier DTMB signal DTMB signal, is that detection terminates, and otherwise carries out other types test；

Receive whether signal is DVB signal according to distinctive Cyclic Prefix detection in DVB signal, be that detection terminates, and otherwise enters Row other types are tested；

After traversal tests above signal type, it is impossible to determine the type of reception signal, then judge to receive in signal not exist State three kinds of ground digital television broadcast signals.

Universal Terrestrial broadcast digital television signals pattern the most according to claim 1 quickly knows method for distinguishing, and its feature exists In, it further comprises the steps of:

Assume that receiving signal is a predefined type, carry out slip auto-correlation to measured signal, calculating sequence of correlation values:

Correlated series value is carried out energy normalized and obtains decision statistics；

Decision statistics is carried out segmentation, and calculates the maximum of every section；

Hypothesis testing level is set and determines decision threshold, compare decision statistics every section maximum and the size of decision threshold and Distance between adjacent maxima.

Universal Terrestrial broadcast digital television signals pattern the most according to claim 2 quickly knows method for distinguishing, and its feature exists In, described judgement includes:

If decision statistics is of substantially equal more than the distance between decision threshold, and adjacent maxima, it assumes that set up, terminate Receive the type detection of signal；

Otherwise judge to receive the signal that signal is not assumed type, then carry out other kinds of detection.

Universal Terrestrial broadcast digital television signals pattern the most according to claim 3 quickly knows method for distinguishing, and its feature exists In, according to the autocorrelation detection of PN63 sequence in the synchronization of ATSC signal field, described step receives whether signal is ATSC signal, Comprising:

Carrying out time delay auto-correlation to measured signal, correlation length is 63*4, and correlation distance is 2*63*4；

Sequence of correlation values is carried out energy normalized, calculates decision statistics；

Decision statistics is carried out segmentation, and calculates the maximum of every section；

Whether decision statistics is more than the whether approximately equal of the interval between pre-determined threshold and adjacent maxima；

Being that detection terminates, receiving signal is ATSC signal；

Otherwise carry out other types test.

Universal Terrestrial broadcast digital television signals pattern the most according to claim 3 quickly knows method for distinguishing, and its feature exists In, according to distinctive PN595 Sequence Detection in single carrier DTMB signal frame head, described step receives whether signal is single carrier DTMB signal, comprising:

The docking collection of letters number carries out time delay auto-correlation, and correlation length is 595*4, and correlation distance is (595+3780) * 4；

Sequence of correlation values is carried out energy normalized, calculates decision statistics；

Decision statistics is carried out segmentation, and calculates the maximum of every section；

Whether decision statistics is more than the whether approximately equal of the distance between pre-determined threshold and adjacent maxima；

Being that detection terminates, receiving signal is single carrier DTMB signal；

Otherwise carry out other types test.

Universal Terrestrial broadcast digital television signals pattern the most according to claim 3 quickly knows method for distinguishing, and its feature exists Whether receive signal in, described step according to the autocorrelation detection of PN sequence in two kinds of frame head modes of multicarrier DTMB signal is Multicarrier DTMB signal, comprising:

The docking collection of letters number carries out time delay auto-correlation, and correlation length is 82*4, and correlation distance is (255+82) * 4, calculates decision statistic Amount；

Decision statistics is carried out segmentation, and calculates the maximum of every section；

Whether decision statistics is more than the whether approximately equal of the distance between pre-determined threshold and adjacent maxima；

It is that detection terminates, receives the multicarrier DTMB signal that signal is the first frame head mode；

Otherwise the docking collection of letters number carries out time delay auto-correlation, and correlation length is 511*4, and correlation distance is (511+217) * 4, and calculating is sentenced Certainly statistic；

Decision statistics is carried out segmentation, and calculates the maximum of every section；

Whether decision statistics is more than the whether approximately equal of the distance between pre-determined threshold and adjacent maxima；

It is that detection terminates, receives the multicarrier DTMB signal that signal is the second frame head mode；

Otherwise carry out other types test.

Universal Terrestrial broadcast digital television signals pattern the most according to claim 3 quickly knows method for distinguishing, and its feature exists In, according to distinctive Cyclic Prefix detection in DVB signal, described step receives whether signal is DVB signal, comprising:

Carry out time delay auto-correlation to measured signal；

Sequence of correlation values is carried out energy normalized, calculates decision statistics；

Decision statistics is carried out segmentation, and calculates the maximum of every section；

Whether decision statistics is more than the whether approximately equal of the distance between pre-determined threshold and adjacent maxima；

Being that detection terminates, receiving signal is DVB signal；

Otherwise carry out other types test.

8. the system that a Universal Terrestrial broadcast digital television signals pattern quickly identifies, it is characterised in that including:

ATSC signal detection module, in performing to synchronize according to ATSC signal field, the autocorrelation detection of PN63 sequence receives letter Whether number be ATSC signal, be, detection terminates；Otherwise carry out other types test；

DTMB single-carrier signal detection module, examines according to distinctive PN595 sequence in single carrier DTMB signal frame head for execution Surveying and receive whether signal is single carrier DTMB signal, be, detection terminates, and otherwise carries out other types test；

DTMB multi-carrier signal detection module, for perform according in two kinds of frame head modes of multicarrier DTMB signal PN sequence from Correlation detection receives whether signal is multicarrier DTMB signal, is, detection terminates, and otherwise carries out other types test；

DVB signal detection module, for performing according to whether distinctive Cyclic Prefix detection reception signal in DVB signal is DVB Signal, is that detection terminates, and otherwise carries out other types test.