CN107517092A - Method of estimation, signal synchronization and the method, apparatus of demodulation of waveforms detection threshold value - Google Patents
Method of estimation, signal synchronization and the method, apparatus of demodulation of waveforms detection threshold value Download PDFInfo
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
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- H04J3/00—Time-division multiplex systems
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- H04J3/06—Synchronising arrangements
- H04J3/0635—Clock or time synchronisation in a network
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Abstract
A kind of method, apparatus of the method for estimation of waveforms detection threshold value, signal synchronization and demodulation.The method of estimation of the waveforms detection threshold value includes:When receiving sampled data corresponding with waveform to be detected, Integrator-Comb filtering and recursive filtering are carried out to the sampled data, the waveforms detection threshold value of actual time window is estimated, to be detected according to the waveforms detection threshold value to the waveform to be detected.Using such scheme, the accuracy of waveforms detection can be improved.
Description
Technical field
The present invention relates to signal demodulation techniques field, and in particular to a kind of method of estimation of waveforms detection threshold value,
Signal synchronization and the method, apparatus of demodulation.
Background technology
In smart card communication system, according to International Organization for standardization (International Organization for
Standardization, ISO) related protocol regulation, proximity devices (Proximity Device, PCD)
Need to demodulate the modulation waveform that proximity card (Proximity Card, PICC) is sent.
Because PICC postbacks the uncertainty of time, PCD needs to detect the time point that PICC is specifically postbacked,
The namely synchronous point of the original position of data frame.In addition, PCD also need to detect data frame inside it is same
Beans-and bullets shooter.
At present, when detecting the synchronous point of data frame, PCD is generally pre-configured with a waveforms detection threshold value.
After receiving modulated signal, first the modulated signal is sampled, then to the data progress after sampling
With filtering.After obtaining corresponding filtering data, the filtering data is entered with corresponding waveforms detection threshold value
Row compares, and determines the correct position of synchronous point to be detected.
However, being difficult to the position for accurately determining synchronous point to be detected using the above method, letter is ultimately resulted in
Number demodulation difficulty increase.
The content of the invention
Present invention solves the technical problem that it is how to improve the accuracy of waveforms detection.
In order to solve the above technical problems, the embodiment of the present invention provides a kind of method of estimation of waveforms detection threshold value,
Methods described includes：When receiving sampled data corresponding with waveform to be detected, to the sampled data
Integrator-Comb filtering and recursive filtering are carried out, the waveforms detection threshold value of actual time window is estimated, with basis
The waveforms detection threshold value detects to the waveform to be detected.
Alternatively, described that Integrator-Comb filtering and recursive filtering are carried out to the sampled data, estimation is current
The waveforms detection threshold value of time window, including：The sampled data is inputted to integral comb filter,
The average value of noise in each time window is obtained according to the output of the integral comb filter, wherein,
The length of the time window is the decimation factor of the integral comb filter；By the current time window
The average value of mouth noise is inputted to recursion filter, by the recursion filter according in historical time window
The average value of noise and default renewal weight coefficient, to the average value of the actual time window noise
It is updated；According to the average value of the actual time window noise after renewal, actual time window is estimated
Waveforms detection threshold value.
Alternatively, the integral comb filter includes：The one-level integrator that couples successively, withdrawal device and
One stage of comb wave filter.
Alternatively, the decimation factor of the integral comb filter is suitable to according to the waveforms detection threshold value
Stability is configured in advance.
Alternatively, the decimation factor of the integral comb filter is 2 integral number power.
Alternatively, the average value of the actual time window noise according to after renewal, estimation are current
The waveforms detection threshold value of time window, including：Using default regulation coefficient, to the institute after the renewal
The average value for stating actual time window noise is adjusted, using the numerical value after adjustment as the current time
The waveforms detection threshold value of window, wherein, the regulation coefficient is suitable to offset the integral comb filter
Gain.
Alternatively, the series of the recursion filter is one-level.
Alternatively, the renewal weight coefficient is advance suitable for the renewal speed according to the waveforms detection threshold value
It is configured.
Alternatively, the negative integer power that the renewal weight coefficient is 2.
Alternatively, calculating in each time window before the average value of noise, in addition to：To the sampling
Data carry out matched filtering.
The embodiment of the present invention additionally provides a kind of signal synchronization detecting method, and methods described includes：Using power
Profit requires the method for estimation of any of the above-described kind of waveforms detection threshold value, estimates synchronization to be detected in modulated signal
Waveforms detection threshold value corresponding to point；Based on the waveforms detection threshold value, determine to be checked in the modulated signal
Survey the position of synchronous point.
The embodiment of the present invention additionally provides a kind of signal demodulating method, and methods described includes：Using above-mentioned
Signal synchronization detecting method, determine the position of synchronous point to be detected in modulated signal；Treated according to identified
The position of synchronous point is detected, the modulated signal is demodulated.
The embodiment of the present invention additionally provides a kind of estimation unit of waveforms detection threshold value, and described device includes：
Estimation unit, suitable for when receiving sampled data corresponding with waveform to be detected, to the sampled data
Integrator-Comb filtering and recursive filtering are carried out, the waveforms detection threshold value of actual time window is estimated, with basis
The waveforms detection threshold value detects to the waveform to be detected.
Alternatively, the estimation unit includes：Integral comb filter, suitable for when receive with it is to be detected
Corresponding to waveform during sampled data, based on the sampled data, being averaged for noise in each time window is calculated
Value, wherein, the length of the time window is the decimation factor of the integral comb filter；Recurrence is filtered
Ripple device, average value and default renewal weight system suitable for noise in the historical time window according to storage
Number, is updated to the average value of the actual time window noise；Subelement is estimated, suitable for according to more
The average value of the actual time window noise after new, estimate the waveforms detection threshold value of actual time window.
Alternatively, the integral comb filter includes：The one-level integrator that couples successively, withdrawal device and
One stage of comb wave filter.
Alternatively, the decimation factor of the integral comb filter is suitable to according to the waveforms detection threshold value
Stability is configured in advance.
Alternatively, the decimation factor of the integral comb filter is 2 integral number power.
Alternatively, the estimation unit, suitable for utilizing default regulation coefficient, to the institute after the renewal
The average value for stating actual time window noise is adjusted, using the numerical value after adjustment as the current time
The waveforms detection threshold value of window, wherein, the regulation coefficient is suitable to offset the integral comb filter
Gain.
Alternatively, the series of the recursion filter is one-level.
Alternatively, the renewal weight coefficient is advance suitable for the renewal speed according to the waveforms detection threshold value
It is configured.
Alternatively, the negative integer power that the renewal weight coefficient is 2.
Alternatively, in addition to：Matched filter, suitable for calculating the flat of noise in each time window
Before average, matched filtering, matched filtering data corresponding to acquisition are carried out to the sampled data.
The embodiment of the present invention additionally provides a kind of signal sync detection device, and described device includes：Threshold value is estimated
Unit is counted, suitable for the estimation unit using above-mentioned waveforms detection threshold value, is estimated to be detected in modulated signal
Waveforms detection threshold value corresponding to synchronous point；Detection unit, suitable for based on the waveforms detection threshold value, it is determined that
The position of synchronous point to be detected in the modulated signal.
The embodiment of the present invention additionally provides a kind of signal demodulating equipment, and described device includes：Synchronous detection is single
Member, suitable for the signal sync detection device using preceding claim, determine to be detected same in modulated signal
The position of beans-and bullets shooter；Decoding unit, suitable for the position of the synchronous point to be detected determined by, to the tune
Signal processed is demodulated.
Relative to prior art, the advantage of the invention is that：
Using such scheme, according to the average value of noise in the historical time window of storage, to current time
The average value of window noise is updated, and then can estimate the waveforms detection threshold value of actual time window.
According to the waveforms detection threshold value of the noise level of actual time window, in real time estimation actual time window, phase
For carrying out waveforms detection using fixed waveforms detection threshold value, the letter of different amplitudes can be better adapted to
Number and noise, therefore the accuracy of waveforms detection can be improved.In addition, the ripple is set using such scheme
Shape detection threshold value, the ease for use and adaptability of the setting of waveforms detection threshold value can be improved.
Further, the average value of noise in each time window is obtained using integral comb filter,
Circuit structure is simpler, easy to implement.
Further, the integral number power that the decimation factor for setting integral comb filter is 2, is so averaging
Division during value can use displacement to realize, therefore can easily facilitate and calculate the flat of noise in each time window
Average.
Further, the average value of actual time window noise is updated using recursion filter, can be with
The stability of noise estimation is improved, and then the accurate of the waveforms detection threshold value of actual time window can be improved
Property.
Further, the negative integer power that renewal weight coefficient is 2 is set so that multiplying in recursion filter
Musical instruments used in a Buddhist or Taoist mass can be achieved with simple shifter-adder, and then can save the circuit face shared by recursion filter
Product.
Brief description of the drawings
Fig. 1 is a kind of waveform diagram of TypeA signals；
Fig. 2 is a kind of structural representation of demodulating equipment in the prior art；
Fig. 3 is the waveform diagram that detection is synchronized using synchronization detecting method of the prior art；
Fig. 4 is a kind of flow chart of the method for estimation of waveform threshold value in the embodiment of the present invention；
Fig. 5 is a kind of structural representation of estimation unit in the embodiment of the present invention；
Fig. 6 is one kind that detection is synchronized using the method for estimation of the waveform threshold value in the embodiment of the present invention
Waveform diagram；
Fig. 7 is to synchronize the another of detection using the method for estimation of the waveform threshold value in the embodiment of the present invention
Kind waveform diagram；
Fig. 8 is a kind of structural representation of signal demodulating equipment in the embodiment of the present invention.
Embodiment
In the agreements of ISO 14443, the data that PICC is sent need to be modulated at transmission rate for 848K's
On square wave, the transmission rate is that 848K square wave is referred to as subcarrier.PCD needs to modulate subcarrier
Signal is demodulated, and obtains the data of PICC transmissions.
Below using the modulated signal as TypeA signals and transmission rate specified in the agreements of ISO 14443
Exemplified by 106K, demodulation method of the prior art is described in detail：
Reference picture 1, the data encoding of TypeA signals have 3 kinds of waveforms, are referred to as sequence D, E and F.
Wherein, sequence D counterlogic " 1 ", sequence E counterlogics " 0 ", sequence F correspond to sign off.
Meanwhile the agreements of ISO 14443 provide：Data communication is started with sequence D.Therefore, to the modulation of the type
Demodulating process corresponding to signal can be divided into 3 steps：
First, the detection sequence D in the data that PCD is received.If detecting sequence D, the tune is represented
Signal processed reaches.Meanwhile the position of bit bit boundary can be oriented according to the position of sequence D, also
It is the original position of data frame corresponding to the modulated signal；
Secondly, can be the waveform received by elementary event unit according to the position of bit bit boundary
(Elementary Time Unit, ETU) carries out being divided into multistage, one bit period of each section of correspondence；
Finally, it is sequence D, sequence E or sequence F respectively to judge ready-portioned each section.If sequence
D is just decoded as 1, if sequence E is just decoded as 0, if sequence F just stops receiving.
It is exactly synchronous that the key point entirely demodulated is can be seen that from the above-mentioned demodulating process to TypeA signals
The detection of point.If synchronous point is confused, the division error of sequence, whole decoding is with regard to completely chaotic.And such as
Fruit synchronous point position accurate positioning, then follow-up Decision Decoding also can be relatively easy.
In actual applications, reference picture 2 and Fig. 3, it is (i.e. first in order to improve the detection of first sequence D
Bag detection) accuracy, typically all can be first with matched filter after being sampled to the data received
21, matched filtering is carried out to data d1 after sampling, obtains matched filtering data d2.And then recycle first packet
Detector 22 finds the point more than default waveforms detection threshold value Th1 in matched filtering data d2,
The envelope peak point in first sequence D, i.e. point a are exactly found in matched filtering data, so as to
To orient the border of first sequence D.Last decoder 23 can be according to the sequence D oriented
Border, extraction judgement is carried out in specific cycle time point, completes the demodulation of data.
In above-mentioned demodulating process, waveforms detection threshold value Th1 is pre-configured, is entirely being demodulated
During will not generally change.However, due to the reasons such as external environment change and link gain, noise
Often change with the amplitude of signal in very big dynamic range, such as, when noise and all smaller signal,
Waveforms detection threshold value Th1 is set may be too big, then PCD easily misses PICC signal back.When making an uproar
When sound and all larger signal amplitude, waveforms detection threshold value Th1 is set may be too small, then PCD will easily make an uproar
Sound is determined as signal, causes the confusion of subsequent demodulation.Therefore, fixed waveforms detection threshold value Th1 is passed through
The accuracy for carrying out waveforms detection is poor.
In view of the above-mentioned problems, the embodiments of the invention provide a kind of method of estimation of waveforms detection threshold value, should
With methods described, according to the average value of noise in the historical time window of storage, actual time window is made an uproar
The average value of sound is updated, and then can estimate the waveforms detection threshold value of actual time window.According to work as
The noise level of preceding time window, the waveforms detection threshold value of actual time window is estimated in real time, relative to adopting
Waveforms detection is carried out with fixed waveforms detection threshold value, the noise and letter of different amplitudes can be better adapted to
Number, improve the accuracy of waveforms detection.
It is understandable to enable above-mentioned purpose, feature and the beneficial effect of the present invention to become apparent, with reference to
Accompanying drawing is described in detail to the specific embodiment of the present invention.
The embodiments of the invention provide a kind of method of estimation of waveforms detection threshold value, methods described can include：
When receiving sampled data corresponding with waveform to be detected, integration comb is carried out to the sampled data
Shape filters and recursive filtering, estimates the waveforms detection threshold value of actual time window, to be examined according to the waveform
Threshold value is surveyed to detect the waveform to be detected.
In specific implementation, comb filter and recursion filter can be respectively adopted, during estimating current
Between window waveforms detection threshold value.Specifically, reference picture 4, estimated using comb filter and recursion filter
The waveforms detection threshold value of meter actual time window may include steps of：
Step 41, the sampled data is inputted to integral comb filter, filtered according to the Integrator-Comb
The output of ripple device obtains the average value of noise in each time window.
In specific implementation, when receiving waveform to be detected, generally treated first with A/D converter to described
Detection waveform is sampled, sampled data corresponding to acquisition.During follow-up progress waveforms detection threshold estimation,
The sampled data can be directly based upon to be estimated, matched filtering can also be carried out to the sampled data
Afterwards, estimated based on the matched filtering data obtained.Due to the matched filtering of sampled data, noise
Than increase, therefore, waveforms detection threshold estimation is carried out based on matched filtering data, can more accurately be obtained
Obtain the waveforms detection threshold value of actual time window.
Because cic filter need not use multiplier, you can LPF computing is carried out to the data of input,
Therefore circuit structure can be simplified, reduce enforcement difficulty.It is of course also possible to use other circuit structures come
The average value of noise in each time window is calculated, it is specific unrestricted.
Referring to Fig. 5, the principle for calculating cic filter 1 noise average in each time window is entered
Row explanation：
In specific implementation, cic filter 1 is generally by integrator 51 and the cascaded series of comb filter 52
Into, also, withdrawal device 53 is provided between afterbody integrator and first order comb filter.Wherein：
The integrator 51 can include：First accumulating operation unit 511 and the first delay arithmetic element
512.The first accumulating operation unit 511 is suitable to input data and the first delay arithmetic element 512
Output result carries out accumulating operation, and it is cumulative that the first delay arithmetic element 512 is suitable to acquisition described first
The output result of arithmetic element 511 postpones the data after M clock cycle.
The withdrawal device 53 is suitable to carry out the result that integrator 51 exports D times of extraction.
The comb filter 52 can include：Calculus of differences unit 521 and second postpones arithmetic element
522.The second delay arithmetic element 522 is suitable to obtain the result delay after the withdrawal device 53 extracts
Data after M clock cycle, the calculus of differences unit 521 are suitable to after being extracted to the withdrawal device 53
Result with described second delay arithmetic element 522 export result make calculus of differences.
The transmission function of the cic filter is：
Wherein, D is the decimation factor of cic filter, and M is difference delay factor.
In embodiments of the invention, in order to save circuit resource, M can select 1, now merely with one
Corresponding delay computing can be achieved in trigger.In order to facilitate calculating, D value can be secondary for 2 integer
Power, such as 64,128 or 256.
In embodiments of the invention, in order to further simplify circuit structure, with the integrator 51 and pectination
Wave filter 52 is illustrated exemplified by only including one-level, it is to be understood that the cic filter also may be used
With comprising multi-stage integrator 51 and comb filter 52, regardless of specific series, not enough to the present invention
Limitation, and within protection scope of the present invention.
The length for making the time window is the decimation factor of the integral comb filter, will be received successively
The sampled data X (n) arrived is inputted to the cic filter 1, can obtain noise in each time window
Average value.
It should be noted that in specific implementation, the length of the time window can be by those skilled in the art
It is configured according to specific application environment.It is understood that the length of the time window is longer,
Namely D value is bigger, and the output of cic filter 1 is also more stable, but due to waveforms detection threshold value
Per D clock cycle estimation once, therefore the estimating speed of waveforms detection threshold value is also slower.
Step 42, the average value of the actual time window noise is inputted to recursion filter, by described
Average value and default renewal weight coefficient of the recursion filter according to noise in the historical time window,
The average value of the actual time window noise is updated.
Be calculated actual time window after the average value of noise, is estimated in each time window waveform inspection
When surveying threshold value, average value that can be by recurrence (IIR) wave filter according to noise in historical time window is right
The average value of actual time window noise is updated, to obtain stable waveforms detection threshold value.Wherein, IIR
Wave filter is a kind of conventional digital filter, is provided with recursion type structure in it, i.e., with anti-in structure
Loop is presented, the average value of noise in historical time window can be utilized, to maintain actual time window noise
The accuracy of average value.
Specifically, referring to Fig. 5, the average value of noise in each time window is obtained by cic filter 1
Afterwards, can input to iir filter 2.
Now, iir filter 2 can include：First multiplying unit 54, the second accumulating operation unit
55, the 3rd delay arithmetic element 56, the second multiplying unit 57.Wherein, first multiplying
Unit 54 is suitable to the output of the cic filter 1 being multiplied with renewal weight coefficient w.Described second is tired
Arithmetic element 55 is added to be suitable to result and the second multiplying unit 57 to the first multiplying unit 54
As a result accumulating operation is made.The 3rd delay arithmetic element 56 is suitable to obtain the second accumulating operation unit
55 output result postpones the data after 1 clock cycle.The second multiplying unit 57 is suitable to will
The data that the 3rd delay arithmetic element 56 is got are multiplied with (1-w).
The transmission function of the iir filter 2 is：
Wherein, w is renewal weight coefficient.
It is updated using output of the iir filter 2 to cic filter 1 so that current time
The noise average of window is not only relevant with the noise in actual time window, also and in historical time window
Noise it is relevant.Noise in the historical time window more remote apart from actual time window, to current time
The noise average of window influences smaller.
It should be noted that in specific implementation, the value of the renewal weight coefficient w can be by this area
Personnel are configured according to specific application environment.It is understood that w value is smaller, iir filter
2 output is more stable, but the renewal speed of waveforms detection threshold value is also slower, i.e., the ratio updated every time
It is smaller.Preferably, in order to save circuit area, can with w value can be 2 negative integer power, than
Such as 1/2,1/4 or 1/8, now, the first multiplying unit 54 and the second multiplying unit 57 can
Only can be achieved with simple shifter-adder.
In specific implementation, waveforms detection threshold value can be set by the described 3rd delay arithmetic element 56
Initial value.The initial value of waveforms detection threshold value can be somewhat bigger than normal, and initial value bigger than normal can be received over time
Normal level is held back, thus avoids, when noise is larger, just having started iir filter 2 and having detected mistake
First packet.
Step 43, according to the average value of the actual time window noise after renewal, actual time window is estimated
Waveforms detection threshold value.
In specific implementation, after the average value for obtaining actual time window noise, a variety of methods can be used
Estimate the waveforms detection threshold value of actual time window.
In one embodiment of this invention, estimate with continued reference to Fig. 5, cic filter 1 and iir filter 2
What meter came out is the average level of noise in actual time window, can be by the output knot of iir filter 2
Fruit is multiplied by scale factor R, the waveforms detection threshold of the result Y (n) of multiplication operation as actual time window
Value.In addition, by the way that the output result of iir filter 2 is multiplied by into scale factor R, CIC can be offset
The gain of wave filter 1, that is, realize the function except D.Wherein, those skilled in the art can be according to specific
Application environment sets R value so that multiplication operation is only added by simple shift, is subtracted and be can be achieved.
Reference picture 6, by taking D=32, M=1, w=1/4 as an example, after sampled data d3 carries out matched filtering,
Obtain matched filtering data d4.Due to D=32, therefore, corresponding time window length is 32 samplings
Point, that is to say, that every 32 samplings point estimation primary wave shape detection threshold value.
Using the method for estimation of the waveforms detection threshold value in the embodiment of the present invention, matched filtering data d4 is entered
Row first packet detects, and obtains synchronous point b.Wherein, curve L1 is threshold estimation curve.On curve L1,
Th0 is the initial value of waveforms detection threshold value, and other numerical value are the estimate of waveforms detection threshold value.
From fig. 6, it can be seen that when estimating waveforms detection threshold value using the method for estimation in the embodiment of the present invention,
As the amplitude of signal and noise is different, the estimate of waveforms detection threshold value is also different.That is, this
Method of estimation in inventive embodiments can better adapt to the change of signal and noise amplitude, using gained
To the estimate of waveforms detection threshold value can more accurately carry out waveforms detection.
In specific implementation, in order to obtain stable waveforms detection threshold value, it will usually select larger D and
Less w.The change of noise is followed as soon as possible for the change of waveforms detection threshold value, it will usually is selected small
Less D and larger w.For example PCD is received after enabling, it is often desirable that the waveforms detection estimated
Threshold value can use as early as possible, that is, wish that waveform detection threshold value renewal speed is fast, can now select
Select larger D.After a period of time, after waveforms detection threshold value converges to rational level, it is often desirable that
The waveforms detection threshold value of estimation is more stable, so the D that selection is a little bit smaller.
When selecting D smaller, the renewal speed of waveforms detection threshold value is fast, but is not sufficiently stable, and now may be used
To select a little bit smaller w to strengthen stability.When selecting D larger, waveforms detection threshold value is more stable,
But renewal speed is too slow, larger w can be now selected to increase renewal speed.In specific implementation,
, can be in different time and application scenario selection or dynamic adjustment D and w in order to meet different demands
Value.
Reference picture 7, by taking sampled data d5 as an example, matched filter obtains matched filtering data d6.Receive
During enabled just beginning, D=32 can be made, now every 32 samplings point estimation primary wave shape detection threshold value,
Renewal speed is very fast, such as Q1 regions in figure.It is through after a period of time, D=64 can be made, i.e., every 64
Point estimation primary wave shape detection threshold value is sampled, such as Q2 regions in figure.Afterwards, D=128 can also be made, i.e.,
Every waveform detection threshold value of 128 point estimation, such as Q3 regions in figure.Finally give synchronous point c.
It should be noted that the waveform threshold estimation method in the embodiment of the present invention, can be not only used for letter
In number synchronous detection, can also be applied to other side, as long as the application environment needs estimation waveforms detection
Threshold value.
Using the method for estimation of the waveforms detection threshold value in the embodiment of the present invention it can be seen from the above
Waveforms detection is carried out, waveforms detection threshold value, Jin Erke can be obtained in real time according to the intensity of signal and noise
To improve the accuracy of waveforms detection.In addition, carried out using the structure of cic filter and iir filter
The estimation of waveforms detection threshold value, can be according to the requirement of stability and renewal speed, modulated in real time D and w
Value, to meet the different needs of user.
The embodiment of the present invention additionally provides a kind of signal synchronization detecting method, and methods described can include：
Using the method for estimation of above-mentioned waveforms detection threshold value, synchronous point pair to be detected in modulated signal is estimated
The waveforms detection threshold value answered；Based on the waveforms detection threshold value, determine to be detected same in the modulated signal
The position of beans-and bullets shooter.
It should be noted that in an embodiment of the present invention, the method for estimation of the waveforms detection threshold value is not
Only go for detecting the signal based on ISO14443 protocol modulations, can be applicable to detection and be based on it
The signal of its protocol modulation.Also, the method for estimation of the waveforms detection threshold value not only goes for examining
The synchronous point of data frame start position is surveyed, can be applicable to detect the synchronous point inside data frame, such as
Go for detecting the synchronous point inside the TypeB signals based on ISO14443 protocol modulations.
The embodiment of the present invention additionally provides a kind of signal demodulating method, and methods described can include：
Using above-mentioned signal synchronization detecting method, the position of synchronous point to be detected in modulated signal is determined；
According to the position of identified synchronous point to be detected, the modulated signal is demodulated.
Specifically it is referred to the above-mentioned method of estimation to waveforms detection threshold value and signal synchronization detecting method
Description is implemented, and here is omitted.
In order that those skilled in the art more fully understand and realized the present invention, it is corresponding to the above method below
Device be described in detail.
Reference picture 5, the embodiment of the present invention additionally provide a kind of estimation unit of waveforms detection threshold value, the dress
Putting to include：Estimation unit (not shown), hits corresponding with waveform to be detected is received suitable for working as
According to when, Integrator-Comb filtering and recursive filtering are carried out to the sampled data, estimate actual time window
Waveforms detection threshold value, to be detected according to the waveforms detection threshold value to the waveform to be detected.
Specifically, the estimation unit can include：
Integral comb filter 1, suitable for when receiving sampled data corresponding with waveform to be detected, being based on
The sampled data, the average value of noise in each time window is calculated, wherein, the time window of arbitrary neighborhood
Mouth is continuous；The length of the time window is the decimation factor of the integral comb filter；
Recursion filter 2, suitable for the average value of noise in the historical time window according to storage and default
Weight coefficient w is updated, the average value of the actual time window noise is updated；
Subelement 3 is estimated, suitable for the average value according to the actual time window noise after renewal, estimation
The waveforms detection threshold value of actual time window, with according to the waveforms detection threshold value to the waveform to be detected
Detected.
In specific implementation, the integral comb filter 1 can include：The one-level integration coupled successively
Device 51, withdrawal device 53 and one stage of comb wave filter 52.
In specific implementation, the decimation factor of the integral comb filter 1 is suitable to be examined according to the waveform
The stability for surveying threshold value is configured in advance.
In specific implementation, the decimation factor of the integral comb filter 1 is 2 integral number power.
In specific implementation, the series of the recursion filter 2 is one-level.
In specific implementation, the renewal weight coefficient w is suitable to the renewal according to the waveforms detection threshold value
Speed is configured in advance.
It is described to update the negative integer power that weight coefficient w is 2 in specific implementation.
In specific implementation, the estimation unit can also include：Matched filter (not shown), is suitable to
Calculating in each time window before the average value of noise, matched filtering carried out to the sampled data,
Matched filtering data corresponding to acquisition.The integral comb filter 1 can be based on the matched filtering number
According to the average value for calculating noise in each time window.
In specific implementation, the estimation unit 3, suitable for utilize default regulation coefficient R, to it is described more
The average value of the actual time window noise after new is adjusted, using the numerical value after adjustment as described in
The waveforms detection threshold value of actual time window, wherein, the regulation coefficient R is suitable to offset the integration comb
The gain of shape wave filter 1.
Reference picture 8, the embodiment of the present invention additionally provide a kind of signal sync detection device 91, described device
91 can include：
Threshold estimation unit 911, suitable for the estimation unit using above-mentioned waveforms detection threshold value, suitable for estimation
Waveforms detection threshold value corresponding to synchronous point to be detected in modulated signal；
Detection unit 912, suitable for based on the waveforms detection threshold value, determining to be detected in the modulated signal
The position of synchronous point.
The embodiment of the present invention additionally provides a kind of signal demodulating equipment 90, it is characterised in that including：
Synchronous detection unit 91, suitable for utilizing above-mentioned signal sync detection device, determine in modulated signal
The position of synchronous point to be detected；
Decoding unit 92, suitable for the position of the synchronous point to be detected determined by, to the modulated signal
It is demodulated.
One of ordinary skill in the art will appreciate that all or part of step in the various methods of above-described embodiment
Suddenly it is that by program the hardware of correlation can be instructed to complete, the program can be stored in a computer can
Read in storage medium, storage medium can include：ROM, RAM, disk or CD etc..
Although present disclosure is as above, the present invention is not limited to this.Any those skilled in the art,
Without departing from the spirit and scope of the present invention, can make various changes or modifications, therefore the guarantor of the present invention
Shield scope should be defined by claim limited range.
Claims (24)
- A kind of 1. method of estimation of waveforms detection threshold value, it is characterised in that including：When receiving sampled data corresponding with waveform to be detected, integration comb is carried out to the sampled data Shape filters and recursive filtering, estimates the waveforms detection threshold value of actual time window, to be examined according to the waveform Threshold value is surveyed to detect the waveform to be detected.
- 2. the method for estimation of waveforms detection threshold value as claimed in claim 1, it is characterised in that described to described Sampled data carries out Integrator-Comb filtering and recursive filtering, estimates the waveforms detection threshold value of actual time window, Including：The sampled data is inputted to integral comb filter, according to the defeated of the integral comb filter Go out the average value for obtaining noise in each time window, wherein, the length of the time window is described The decimation factor of integral comb filter；The average value of the actual time window noise is inputted to recursion filter, by the recursive filtering Average value and default renewal weight coefficient of the device according to noise in historical time window, to described current The average value of time window noise is updated；According to the average value of the actual time window noise after renewal, the waveform inspection of actual time window is estimated Survey threshold value.
- 3. the method for estimation of waveforms detection threshold value as claimed in claim 2, it is characterised in that the integration comb Shape wave filter includes：One-level integrator, withdrawal device and the one stage of comb wave filter coupled successively.
- 4. the method for estimation of waveforms detection threshold value as claimed in claim 2, it is characterised in that the integration comb The decimation factor of shape wave filter is suitable to be configured in advance according to the stability of the waveforms detection threshold value.
- 5. the method for estimation of waveforms detection threshold value as claimed in claim 4, it is characterised in that the integration comb The decimation factor of shape wave filter is 2 integral number power.
- 6. the method for estimation of waveforms detection threshold value as claimed in claim 2, it is characterised in that the basis is more The average value of the actual time window noise after new, estimate the waveforms detection threshold value of actual time window, Including：Using default regulation coefficient, to the average value of the actual time window noise after the renewal It is adjusted, the waveforms detection threshold value using the numerical value after adjustment as the actual time window, wherein, The regulation coefficient is suitable to the gain for offsetting the integral comb filter.
- 7. the method for estimation of waveforms detection threshold value as claimed in claim 2, it is characterised in that the recurrence filter The series of ripple device is one-level.
- 8. the method for estimation of waveforms detection threshold value as claimed in claim 7, it is characterised in that the renewal power Weight coefficient is suitable to be configured in advance according to the renewal speed of the waveforms detection threshold value.
- 9. the method for estimation of waveforms detection threshold value as claimed in claim 8, it is characterised in that the renewal power Weight coefficient is 2 negative integer power.
- 10. the method for estimation of the waveforms detection threshold value as described in any one of claim 1~9, it is characterised in that Calculating in each time window before the average value of noise, in addition to：Matched filtering is carried out to the sampled data.
- A kind of 11. signal synchronization detecting method, it is characterised in that including：Using the method for estimation of the waveforms detection threshold value described in any one of claim 1~10, estimation modulation letter Waveforms detection threshold value corresponding to synchronous point to be detected in number；Based on the waveforms detection threshold value, the position of synchronous point to be detected in the modulated signal is determined.
- A kind of 12. signal demodulating method, it is characterised in that including：Using the signal synchronization detecting method described in claim 11, synchronization to be detected in modulated signal is determined The position of point；According to the position of identified synchronous point to be detected, the modulated signal is demodulated.
- A kind of 13. estimation unit of waveforms detection threshold value, it is characterised in that including：Estimation unit, suitable for when receiving sampled data corresponding with waveform to be detected, to the sampling Data carry out Integrator-Comb filtering and recursive filtering, estimate the waveforms detection threshold value of actual time window, with The waveform to be detected is detected according to the waveforms detection threshold value.
- 14. the estimation unit of waveforms detection threshold value as claimed in claim 13, it is characterised in that the estimation Unit includes：Integral comb filter, suitable for when receiving sampled data corresponding with waveform to be detected, being based on The sampled data, the average value of noise in each time window is calculated, wherein, the length of the time window Spend for the decimation factor of the integral comb filter；Recursion filter, suitable for the average value of noise in the historical time window according to storage and default Weight coefficient is updated, the average value of the actual time window noise is updated；Subelement is estimated, suitable for the average value according to the actual time window noise after renewal, estimation The waveforms detection threshold value of actual time window.
- 15. the estimation unit of waveforms detection threshold value as claimed in claim 14, it is characterised in that the integration Comb filter includes：One-level integrator, withdrawal device and the one stage of comb wave filter coupled successively.
- 16. the estimation unit of waveforms detection threshold value as claimed in claim 13, it is characterised in that the integration The decimation factor of comb filter is suitable to be configured in advance according to the stability of the waveforms detection threshold value.
- 17. the estimation unit of waveforms detection threshold value as claimed in claim 16, it is characterised in that the integration The decimation factor of comb filter is 2 integral number power.
- 18. the estimation unit of waveforms detection threshold value as claimed in claim 14, it is characterised in that the estimation Subelement, suitable for utilizing default regulation coefficient, to the actual time window noise after the renewal Average value be adjusted, the waveforms detection threshold value using the numerical value after adjustment as the actual time window, Wherein, the regulation coefficient is suitable to the gain for offsetting the integral comb filter.
- 19. the estimation unit of waveforms detection threshold value as claimed in claim 14, it is characterised in that the recurrence The series of wave filter is one-level.
- 20. the estimation unit of waveforms detection threshold value as claimed in claim 19, it is characterised in that the renewal Weight coefficient is suitable to be configured in advance according to the renewal speed of the waveforms detection threshold value.
- 21. the estimation unit of waveforms detection threshold value as claimed in claim 20, it is characterised in that the renewal Weight coefficient is 2 negative integer power.
- 22. the estimation unit of the waveforms detection threshold value as described in any one of claim 13~21, it is characterised in that The estimation unit also includes：Matched filter, suitable for calculating in each time window before the average value of noise, to described Sampled data carries out matched filtering, matched filtering data corresponding to acquisition.
- A kind of 23. signal sync detection device, it is characterised in that including：Threshold estimation unit, suitable for utilizing the waveforms detection threshold value described in any one of claim 13~22 Estimation unit, estimate waveforms detection threshold value corresponding to synchronous point to be detected in modulated signal；Detection unit, suitable for based on the waveforms detection threshold value, determining to be detected same in the modulated signal The position of beans-and bullets shooter.
- A kind of 24. signal demodulating equipment, it is characterised in that including：Synchronous detection unit, suitable for utilizing the signal sync detection device described in claim 23, it is determined that adjusting The position of synchronous point to be detected in signal processed；Decoding unit, suitable for the position of the synchronous point to be detected determined by, the modulated signal is entered Row demodulation.
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