CN106052852A - Pulse sound signal detection method and device - Google Patents

Abstract

An embodiment of the invention discloses a pulse sound signal detection method, which is used for increasing accuracy of pulse sound signal detection. The pulse sound signal detection method comprises the steps of: sampling pulse sound signals in channels of a microphone array to obtain sampled sound signals of the channels; judging whether intensive background noise exists in the sampled sound signals, if so, performing noise reduction processing on the sampled sound signals and then calculating frame energy of the sampled sound signals after noise reduction processing, if not, directly calculating frame energy of the sampled sound signals; and detecting pulse sound signals of the channels according to the frame energy of the sampled sound signals and existence state of the sampled sound signals. The embodiment of the invention further discloses a pulse sound signal detection device, which is used for increasing accuracy of pulse sound signal detection.

Description

The detection method of a kind of pulse sound signal and device

Technical field

The present invention relates to acoustical signal processing technical field, particularly relate to detection method and the device of a kind of pulse sound signal.

Background technology

Cannon sound, shot, explosive sound isopulse sound are detected, orient, when positioning, need first pulse sound to be believed Number detect reliably and extract.

The method typically used when detecting pulse sound at present has power spectrum detection method, energy measuring method, statistics inspection Survey method, constant false alarm rate detection method etc..Power spectrum detection method carries out Short Time Fourier Transform to signal, seeks the power of every segment signal Spectrum, does ratio by the power spectrum of the power spectrum and whole segment signal of paying close attention to frequency range, when this ratio is more than certain threshold value, it is believed that have Target occurs；Energy measuring method asks for the short-time energy of signal, when this energy is more than certain threshold value, it is believed that target pulse sound Signal occurs, or when current short-time energy is more than certain threshold value with the ratio of previous short-time energy, it is believed that target pulse sound is believed Number occur；Statistic mixed-state method carries out target detection according to Maximum-likelihood estimation ratio, has the maximum likelihood of target in current slot Estimate when the ratio with aimless Maximum-likelihood estimation is more than certain threshold value, it is believed that target pulse acoustical signal occurs；Permanent empty The threshold value that alert rate detection method uses can change along with background environment, can use the power of observation in certain period of time, energy, The statistics such as variance are as adaptive threshold.

But, comprehensive analysis these pulse sound detection algorithms existing, they common features are to be required for a threshold value, Or rule of thumb given hard-threshold, or adaptive change is soft after using certain method to calculate environmental data Threshold value, can be referred to as single threshold detection algorithm by these detection algorithms.This single threshold detection algorithm detection probability exists Determined by the size of threshold value and sound source sound pressure level completely under region spaciousness, environment quiet, calm ideal conditions, signal detected It is rear that directly carrying out continuation in time domain just can extract complete impulse waveform.When acoustic detection implantation of device is at very noisies such as oil machines The signal that side, source receives will drown out in background noise, and under the conditions of windy day, wind noise will increase acoustic detection equipment Detection false alarm rate, these dislike conditions slightly and will have a strong impact on acoustic detection equipment to the detection probability of pulse sound and detection accuracy, And have influence on the integrity extracting pulse sound signal further.

Summary of the invention

Embodiments provide the detection method of a kind of pulse sound signal, can not be affected by environment noise, subtract The detection false alarm rate of few acoustic detection equipment, promotes probability and the accuracy of detection.

The detection method of a kind of pulse sound signal that embodiment of the present invention first aspect provides, comprises the steps:

Step 1: sample the pulse sound signal of passage each in microphone array, obtains the sampling sound letter of each passage Number；

Step 2: judge whether there is strong background noise in described sampling acoustical signal, the most first believes described sampling sound Number carry out noise reduction process, then calculate the frame energy of the described sampling acoustical signal after noise reduction process；If it is not, adopt described in then directly calculating The frame energy of sample acoustical signal；

Step 3: detect each logical according to the frame energy of described sampling acoustical signal and the existence of described sampling acoustical signal The pulse sound signal in road.

In conjunction with the first aspect of the embodiment of the present invention, in the first implementation of embodiment of the present invention first aspect, Existence at the frame energy according to described sampling acoustical signal and described sampling acoustical signal detects the pulse sound letter of each passage After number, also include: when meeting prerequisite, determine that the pulse sound signal of each passage detected is target pulse sound letter Number.

In conjunction with the first implementation of embodiment of the present invention first aspect, in the second of embodiment of the present invention first aspect Plant in implementation, described when meeting prerequisite, determine that the pulse sound signal of each passage of detection is target pulse sound Also comprise determining whether before signal to meet prerequisite；

Described determine whether that meeting prerequisite includes:

Determine detection each passage pulse sound signal in any two passages pulse sound signal relative coefficient whether More than the first predetermined threshold value, if not, it is determined that be unsatisfactory for prerequisite；If, it is determined that the pulse sound signal length of each passage Whether more than the second predetermined threshold value, if not, it is determined that be unsatisfactory for prerequisite；If, it is determined that the pulse sound signal of each passage Signal to noise ratio whether more than the 3rd predetermined threshold value, if not, it is determined that be unsatisfactory for prerequisite, if, it is determined that meet preset bar Part.

In conjunction with the second implementation of embodiment of the present invention first aspect, in the 3rd of embodiment of the present invention first aspect In kind of implementation, after determining and meeting prerequisite, described target pulse acoustical signal is saved in caching, and records institute State original position and the end position of target pulse acoustical signal, carry out for according to described original position and described end position The extraction of target pulse acoustical signal；

After determining and being unsatisfactory for prerequisite, each channel pulse acoustical signal that will detect is removed, and re-executes step Rapid 1.

In conjunction with the first aspect of the embodiment of the present invention, in the 4th kind of implementation of embodiment of the present invention first aspect, Described judge whether described sampling acoustical signal exists strong background noise, the most described sampling acoustical signal is carried out noise reduction Process includes:

Judge whether the time-domain signal of described sampling acoustical signal exists periodically, the most then to described sampling acoustical signal Time-domain signal carries out frequency domain transform, if obtaining the line spectrum with harmonic relationships, then carries out the described line spectrum with harmonic relationships Suppression.

In conjunction with the first aspect of the embodiment of the present invention, in the 4th kind of implementation of embodiment of the present invention first aspect, Described judge whether described sampling acoustical signal exists strong background noise, the most described sampling acoustical signal is carried out noise reduction Process includes:

When the existence of described sampling acoustical signal is 0 or 1, if the frame energy of described sampling acoustical signal more than preset Peak, it is determined that present sample acoustical signal is pulse sound signal, and present sample acoustical signal is put in the second caching, record The initial point position of present sample acoustical signal；

If the frame energy of described sampling acoustical signal is more than the intermediate value preset and less than the peak preset, it is determined that current Sampling acoustical signal is doubtful pulse sound signal, and re-executes step 1；

If the frame energy of described sampling acoustical signal is more than the minimum preset and less than the intermediate value preset, it is determined that current Sampling acoustical signal is noise, and re-executes step 1；

When the existence of described sampling acoustical signal is 2, if during the frame energy of described sampling acoustical signal is more than presetting Between be worth and less than the peak be located at, it is determined that present sample acoustical signal is pulse sound signal, and present sample acoustical signal is put Enter in caching；

If the frame energy of described sampling acoustical signal is more than the minimum preset and less than the intermediate value being located at, then record is current The end point position of sampling acoustical signal, and the initial point position and end point position calculation according to present sample acoustical signal go out currently The length of sampling acoustical signal；

When the existence of described sampling acoustical signal is 3, postpone according to the length of the present sample acoustical signal calculated Deposit middle extraction pulse sound signal.

The detection device of a kind of pulse sound signal that embodiment of the present invention second aspect provides, including: sampling module, it is used for The pulse sound signal of passage each in microphone array is sampled, obtains the sampling acoustical signal of each passage；

Judge module, is used for judging whether there is strong background noise in described sampling acoustical signal, the most first adopts described Sample acoustical signal carries out noise reduction process, then calculates the frame energy of the described sampling acoustical signal after noise reduction process；If it is not, the most directly calculate The frame energy of described sampling acoustical signal；

Detection module, for the existence detection of the frame energy according to described sampling acoustical signal and described sampling acoustical signal Go out the pulse sound signal of each passage.

In conjunction with the second aspect of the embodiment of the present invention, in the first implementation of embodiment of the present invention second aspect, Described device also includes that first determines module, and described first determines module, for when meeting prerequisite, determines and detects The pulse sound signal of each passage is target pulse acoustical signal.

In conjunction with the first implementation of embodiment of the present invention second aspect, in the second of embodiment of the present invention second aspect In kind of implementation, described device also includes that second determines module, and described second determines that module is used to determine whether to meet preset Condition, described second determines that module is specifically for determining the pulse sound of any two passages in the pulse sound signal of each passage of detection Whether the relative coefficient of signal is more than the first predetermined threshold value, if not, it is determined that be unsatisfactory for prerequisite；If, it is determined that each Whether the pulse sound signal length of passage is more than the second predetermined threshold value, if not, it is determined that be unsatisfactory for prerequisite；The most true Whether the signal to noise ratio of the pulse sound signal of fixed each passage is more than the 3rd predetermined threshold value, if not, it is determined that be unsatisfactory for prerequisite, if It is, it is determined that meet prerequisite.

In conjunction with the second implementation of embodiment of the present invention second aspect, in the 3rd of embodiment of the present invention second aspect In kind of implementation, described device also includes preserving module and removing module, described preservation module for determine meet preset After condition, described target pulse acoustical signal is saved in caching, and records the original position of described target pulse acoustical signal And end position, for carrying out the extraction of target pulse acoustical signal according to described original position and described end position, described Removing module is used for, and after determining and being unsatisfactory for prerequisite, each channel pulse acoustical signal that will detect is removed.

In conjunction with the second aspect of the embodiment of the present invention, in the 4th kind of implementation of embodiment of the present invention second aspect, Whether described judge module exists periodically specifically for the time-domain signal judging described sampling acoustical signal, the most then to described The time-domain signal of sampling acoustical signal carries out frequency domain transform, if obtaining the line spectrum with harmonic relationships, then has harmonic wave pass to described The line spectrum of system suppresses.

In conjunction with the second aspect of the embodiment of the present invention, in the 5th kind of implementation of embodiment of the present invention second aspect, Described detection module specifically for:

When the existence of described sampling acoustical signal is 0 or 1, if the frame energy of described sampling acoustical signal more than preset Peak, it is determined that present sample acoustical signal is pulse sound signal, and present sample acoustical signal is put in the second caching, record The initial point position of present sample acoustical signal；

If the frame energy of described sampling acoustical signal is more than the intermediate value preset and less than the peak preset, it is determined that current Sampling acoustical signal is doubtful pulse sound signal, and re-executes step 1；

If the frame energy of described sampling acoustical signal is more than the minimum preset and less than the intermediate value preset, it is determined that current Sampling acoustical signal is noise, and re-executes step 1；

When the existence of described sampling acoustical signal is 2, if during the frame energy of described sampling acoustical signal is more than presetting Between be worth and less than the peak be located at, it is determined that present sample acoustical signal is pulse sound signal, and present sample acoustical signal is put Enter in caching；

If the frame energy of described sampling acoustical signal is more than the minimum preset and less than the intermediate value being located at, then record is current The end point position of sampling acoustical signal, and the initial point position and end point position calculation according to present sample acoustical signal go out currently The length of sampling acoustical signal；

When the existence of described sampling acoustical signal is 3, postpone according to the length of the present sample acoustical signal calculated Deposit middle extraction pulse sound signal.

The method of a kind of pulse sound signal detection that the embodiment of the present invention provides, including to passage each in microphone array Pulse sound signal is sampled, and obtains the sampling acoustical signal of each passage, it is judged that whether there is strong background in this sampling acoustical signal and makes an uproar Sound, the most first carries out noise reduction process, then calculates the frame energy of this sampling acoustical signal after noise reduction process this sampling acoustical signal Amount；If it is not, the most directly calculate the frame energy of this sampling acoustical signal, according to frame energy and this sampling acoustical signal of this sampling acoustical signal Existence detect the pulse sound signal of each passage, relative to prior art, the embodiment of the present invention is at detection pulse sound letter Number time can carry out noise reduction process, can effectively get rid of the impact on testing result of the noise in environment, thus promote detection The probability of pulse sound signal and accuracy.

Accompanying drawing explanation

Fig. 1 is the first embodiment flow chart of steps of pulse sound signal detecting method provided by the present invention；

Fig. 2 is microphone array structural representation provided by the present invention；

Fig. 3 is the second embodiment flow chart of steps of pulse sound signal detecting method provided by the present invention；

Fig. 4 is the time domain beamformer of oil machine noise provided by the present invention；

Fig. 5 is the frequency-domain waveform figure of oil machine noise provided by the present invention；

Fig. 6 is the time domain beamformer of the sampling acoustical signal before noise suppressed provided by the present invention；

Fig. 7 is the time domain beamformer of the sampling acoustical signal after noise suppressed provided by the present invention；

Fig. 8 is the 3rd embodiment flow chart of steps of pulse sound signal detecting method provided by the present invention；

Fig. 9 is the time domain beamformer of 3 channel pulse acoustical signals provided by the present invention；

Figure 10 is the power spectrum figure of 3 channel pulse acoustical signals provided by the present invention；

Figure 11 is pulse sound signal reverberation oscillogram provided by the present invention；

Figure 12 is the first embodiment structural representation of pulse sound signal supervisory instrument provided by the present invention；

Figure 13 is the second example structure schematic diagram of pulse sound signal supervisory instrument provided by the present invention.

Detailed description of the invention

Embodiments provide a kind of method that can promote pulse sound signal detection correctness, shown in the present embodiment Pulse sound signal detecting method be applied to pulse sound signal supervisory instrument harmony signal detector.

In order to make those skilled in the art be more fully understood that the present invention program, below in conjunction with in the embodiment of the present invention Accompanying drawing, is clearly and completely described the technical scheme in the embodiment of the present invention, it is clear that described embodiment is only The embodiment of a present invention part rather than whole embodiments.Based on the embodiment in the present invention, ordinary skill people The every other embodiment that member is obtained under not making creative work premise, all should belong to the model of present invention protection Enclose.

The (if present) such as term " first " in description and claims of this specification and above-mentioned accompanying drawing, " second " It is for distinguishing similar object, without being used for describing specific order or precedence.Should be appreciated that the number of so use According to exchanging in the appropriate case, in order to the embodiments described herein can with the content except here illustrating or describing with Outer order is implemented.Additionally, term " includes " and " having " and their any deformation, it is intended that cover non-exclusive bag Contain, such as, contain series of steps or the process of unit, method, system, product or equipment is not necessarily limited to clearly to list Those steps or unit, but can include that the most clearly list or intrinsic for these processes, method, product or equipment Other step or unit.

Introduce the first embodiment of pulse sound signal detecting method in the embodiment of the present invention first below, this pulse sound signal Detection method can be applied in military field, for detecting the pulse sound signal of shot, cannon sound, explosive sound.

As it is shown in figure 1, the detection method of described pulse sound signal includes:

Step 101, pulse sound signal to passage each in microphone array are sampled, and obtain the sampling sound letter of each passage Number.

In the present embodiment, the form initially with branched microphone composition array completes the pickup of signal, obtains each passage Pulse sound signal.Array structure composition includes 4 microphone array element Isosorbide-5-Nitrae root horizontal array bars 2, referring specifically to Fig. 2.The most right Each microphone channel is sampled by frame, and frame length is rule of thumb set, and has just started to gather several frame data and has not processed, has only entered Row accumulation, sample frequency can preset.

It should be noted that in other embodiments, also needed to carry out parameter initialization, parameter before performing step 1 Including threshold value PWMTH, frame energy in signal existence ST, frame energy threshold PWTH, frame energy Low threshold PWLTH, frame energy High threshold PWHTH, array signal correlation coefficient threshold CFTH, frequency domain snr threshold FSNRTH, maximum impulse ripple persistence length Threshold value MAXLS, signal existence ST is initially 0, and frame energy threshold PWTH is initially empirically determined value or last time Value before equipment shutdown, PWLTH=1.5 × PWTH, PWMTH=3 × PWTH, PWHTH=6 × PWTH, correlation coefficient threshold CFTH=0.3, frequency domain snr threshold FSNRTH=7dB, maximum impulse ripple persistence length threshold value MAXLS=0.5 × fs, fs is Sample rate.

Step 102, judge whether described sampling acoustical signal exists strong background noise, the most then perform step 103, if No, then perform step 104；

Step 103, first described sampling acoustical signal is carried out noise reduction process, then calculate the letter of the described sampling sound after noise reduction process Number frame energy；

The frame energy of step 104, the directly described sampling acoustical signal of calculating；

In the present embodiment, by the analysis to existing detection technique, carry out during signal detection, using signal time domain system Metering or frequency domain statistic, so sampled signal must be carried out certain process to extract the amount that can be used for detection, this Bright using the energy asking for certain frame length time-domain signal, computing formula is as follows:

$PW=\underset{i=1}{\overset{N}{\Σ}}\left|x\left(i\right)\right|---\left(1\right)$

In formula (2), N is frame length, x (i), i=1 ... N sequence of time-domain samples, | | represent and seek absolute value.

Strong background noise in the present embodiment includes oil machine noise, the noise of this class of Vehicle Engine Noise, acoustic detection Needing to be placed on generating oil machine side in the case of equipment is a lot of in use, or be placed on the roadside of running car, this all can make Becoming and there is strong background noise in environment near acoustic detection equipment, when having pulsed sound to send, microphone array arrives except picking up Pulsed sound also can pick up strong background noise signal, useful pulse sound will be caused to be submerged in completely in strong noise background, as Fruit does not processes, and manually vision all cannot find pulse sound signal, is difficult to the arteries and veins being tested with by automatic detection algorithm Rush acoustical signal, so strong background noise suppression must be carried out.

Step 105, detect respectively according to the frame energy of described sampling acoustical signal and the existence of described sampling acoustical signal The pulse sound signal of passage.

Below the second embodiment of pulse sound signal detecting method provided by the present invention is described, as it is shown on figure 3, The detection method of described pulse sound signal includes:

Step 201, pulse sound signal to passage each in microphone array are sampled, and obtain the sampling sound letter of each passage Number.

The method that in the present embodiment, the executive mode of step 201 is referred to step 101, the most specifically limits Fixed.

Step 202, judge whether the time-domain signal of described sampling acoustical signal exists periodically, the most then perform step 203。

In the present embodiment, potentially including strong background noise in sampling acoustical signal, strong background noise includes oil machine noise, vehicle The noise of this class of engine noise, owing to the time-domain signal of strong background noise has periodic feature, therefore can pass through Judge whether the time-domain signal of sampling acoustical signal exists periodically, so that it is determined that whether sampling acoustical signal includes that strong background is made an uproar Sound.Such as the when of oil machine working stability, sampling obtains time-domain signal as shown in Figure 4, it can be seen that have the cycle clearly Property.

Step 203, time-domain signal to described sampling acoustical signal carry out frequency domain transform, if obtaining the line with harmonic relationships Spectrum, then suppress the described line spectrum with harmonic relationships.

In the present embodiment, by strong background noise for illustrating as a example by oil machine noise, when determining that sampling acoustical signal includes During oil machine noise, the time-domain signal of oil machine noise is carried out Fourier transformation and obtains frequency-region signal as shown in Figure 5, it can be seen that tool Having obvious line spectrum feature, and all of line spectral frequencies is all based on same fundamental frequency, in Fig. 5, the fundamental frequency of line spectrum is 25Hz, Acoustic signals can change after air borne, and the change of harmonic relationships is less than 1Hz, and this kinds of noise main energetic all collects In on the line spectrum with harmonic relationships, as long as so just can eliminate after line spectrum is suppressed major part noise.

Suppress to find out harmonic wave collection firstly the need of at frequency domain to this line spectrum noise with harmonic wave, true to each harmonic Determining narrow band bandwidth, in whole spectral range, the amplitude that outside retaining each narrow band bandwidth, each Frequency point is corresponding, in each narrow band bandwidth Amplitude corresponding to each Frequency point use the method for batten difference to determine, finally carry out frequency domain inverse transformation and obtain time domain waveform, i.e. For the signal after noise suppressed.

During line-spectrum detection, first signal spectrum is normalized, adopts and search for spectral peak with the following method:

1.. maximum local_max in detection frequency spectrum spectrum；

2.. one minimum local_min1 of each searching and localmin2 in maximum Dynamic Neighborhood, if 2 × Local_max/ (local_min1+localmin2) is more than certain threshold value, then it is significant for being considered as spectral peak, can select.

3.. carry out harmonic wave collection detection according to below equation:

|frequency(k)-f_m×i_mk|≤ε (2)

Wherein frequency (k) represents the frequency that spectral peak is corresponding, f_mThe fundamental frequency assumed that, i_mkCorresponding overtone order, ε is The threshold value set.If detecting, some frequencies and a certain characteristic frequency have obvious harmonic relationships, then it is assumed that detect one humorous Ripple collection, finds corresponding fundamental frequency simultaneously.

When signal does not exists harmonic relationships, the line spectrum that amplitude is bigger is suppressed.Fig. 6 show and has collected by force The pulse sound time-domain signal of background noise, as can be seen from the figure pulse sound Signal-to-Noise is relatively low, is unfavorable for target detection, figure 7 show the time-domain signal after noise suppressed, the bigger lifting that as can be seen from the figure pulse sound Signal-to-Noise obtains, and have It is beneficial to follow-up target detection work.

Step 204, after the described line spectrum with harmonic relationships is suppressed, calculate the frame energy of described sampling acoustical signal Amount；

Step 205, detect respectively according to the frame energy of described sampling acoustical signal and the existence of described sampling acoustical signal The pulse sound signal of passage.

In the present embodiment, step 204 includes:

S2051, when the existence of described sampling acoustical signal is 0 or 1, if the frame energy of described sampling acoustical signal is more than The peak preset, it is determined that present sample acoustical signal is pulse sound signal, and present sample acoustical signal is put into the second caching In, the initial point position of record present sample acoustical signal；If the frame energy of described sampling acoustical signal more than preset intermediate value and Less than the peak preset, it is determined that present sample acoustical signal is doubtful pulse sound signal, and re-executes step 1；If it is described The frame energy of sampling acoustical signal is more than the minimum preset and less than the intermediate value preset, it is determined that present sample acoustical signal is for making an uproar Sound, and re-execute step 1；

S2052, when the existence of described sampling acoustical signal is 2, if the frame energy of described sampling acoustical signal is more than pre- If intermediate value and less than the peak be located at, it is determined that present sample acoustical signal is pulse sound signal, and by present sample sound Signal is put in caching；If the frame energy of described sampling acoustical signal is more than the minimum preset and less than the intermediate value being located at, then Record the end point position of present sample acoustical signal, and the initial point position and end point position according to present sample acoustical signal is counted Calculate the length of present sample acoustical signal；

S2053, when the existence of described sampling acoustical signal is 3, according to the length of the present sample acoustical signal calculated Spend from caching, extract pulse sound signal.

It should be noted that the pulse sound signal that the sound sources such as cannon produce is not the most preferable pulse sound, meeting in time domain Continue regular hour length, experienced by from no signal, signal occurs, signal is lasting, the such signal of signal ended exists shape State course, corresponding short time frame energy also can experience from low-yield, high-energy, low-yield such signal energy state course, So binding signal existence and signal energy state course propose the detection of the double state of sampling when pulse sound signal detection Method, signal energy state is determined by high, medium and low frame energy threshold (PWLTH, PWMTH, PWHTH), and signal energy state controls The evolution of signal existence.

What before the appearance of pulse sound signal, microphone received is all that ambient noise signal frame energy is relatively low, so setting low frame Energy threshold represents environmental noise power, represents that doubtful signal occurs, through signal when frame energy is more than low frame energy threshold Duration impulse acoustical signal bigger frame energy will necessarily occur, so represent determine when frame energy is more than high frame energy threshold Signal occurs, after determining that signal occurs, continues frame energy and represents that persistent signal occurs, when frame energy is little more than middle frame energy threshold When middle frame energy threshold, represent signal ended, detect complete.

A certain size caching buff1 is set, for storage environment noise data, takes out environment noise when buff1 is full Data, computing environment noise average energy, as frame energy threshold PWTH.Owing to the pulse sound that affects of region, landform is believed Reverberation in various degree can be produced when number being transferred to microphone receiving area, cause smear longer, so frame energy in She Dinging Thresholding PWMTH detects for signal ended, and PWMTH is relatively bigger than for detecting low frame energy threshold PWLMTH when signal occurs, The hangover of signal can be reduced the most to a certain extent.Set bigger caching buff2, for depositing the pulse being confirmed Acoustical signal, after pulse sound signal detection, buff2 also will not be filled with, so by initial point position X1 recorded and end point Position X2 determines taking-up signal from buff2.

Signal extraction complete and after further confirming that signal existence ST, initial point position X1, end point position X2 resets reset.

Schematic flow sheet with reference to the 3rd embodiment that Fig. 8, Fig. 8 are pulse sound detection method of the present invention.

First embodiment based on pulse sound detection method, the method also includes:

Step 106, when meeting prerequisite, determine that the pulse sound signal of each passage detected is target pulse sound letter Number.

Wherein it is determined that the step meeting prerequisite includes:

1061, determine detection each passage pulse sound signal in the relative coefficient of pulse sound signal of any two passages Whether more than the first predetermined threshold value, if not, it is determined that be unsatisfactory for prerequisite；If, it is determined that the pulse sound signal of each passage Whether length is more than the second predetermined threshold value, if not, it is determined that be unsatisfactory for prerequisite；If, it is determined that the pulse sound of each passage Whether the signal to noise ratio of signal is more than the 3rd predetermined threshold value, if not, it is determined that be unsatisfactory for prerequisite, if, it is determined that meet pre- Put condition.

It should be noted that through signal detection the pulse sound that extracts sometimes and target pulse acoustical signal, herein Target pulse acoustical signal includes cannon sound, shot or explosive sound, after the most wind-induced noise signal is received by microphone The most also it is a kind of pulse sound, so needing the signal to extracting to further confirm that.The present embodiment uses multichannel microphone array Unit's signal correlation method differentiates whether the pulse sound detected is wind noise.If what each passage microphone array element collected is The pulse sound of same target, then should have the strongest dependency；And wind noise likely causes on part microphone Pulse sound, at this moment microphone array element dependency two-by-two will not be the highest, if relative coefficient is less than the first predetermined threshold value The situation of CFTH, is i.e. unsatisfactory for prerequisite, and regards as noise.

Wherein correlation analysis step is as follows:

A. each passage time domain waveform extracted is carried out power spectrumanalysis, obtain each channel power spectrum waveform, computing formula As follows:

$P_X\left(w\right)=\frac{1}{NW}{\left|\underset{n=0}{\overset{N-1}{\Σ}}x\left(n\right)c\left(n\right)e^{-jnw}\right|}^2---\left(3\right)$

$W=\frac{1}{N}\underset{n=0}{\overset{N-1}{\Σ}}{\left|c\left(n\right)\right|}^2$

In formula, x (n) is sequence of time-domain samples, P_XW () is the power spectrum tried to achieve, c (n) is window function.

B. calculating channel power spectral correlative coefficient two-by-two, computing formula is as follows:

${\mathrm{\η}}_{ij}=\frac{\mathrm{cov}(P_{X_i},P_{X_j})}{\sqrt{\mathrm{cov}(P_{X_i},P_{X_i})\mathrm{cov}(P_{X_j},P_{X_j})}},i,j=1,2,3,4---\left(4\right)$

In formula, variance is sought in cov () expression,Represent that each channel power is composed.

C. the correlation coefficient of minimum is extracted, it may be judged whether less than threshold value CFTH, determine whether the signal of extraction is wind noise.

Above-mentioned correlation analysis is carried out at frequency domain, is because when acoustic array size is bigger, and each array element receives The target acoustic signal time delay arrived is relatively big, directly asks correlation coefficient the least in time domain, is illustrated in figure 9 wherein 3 array elements and receives The same pulse sound arrived, is 0.07 through calculating time domain least correlativing coefficient, and Figure 10 is corresponding power spectrum waveform, Jing Guoji Calculating frequency domain least correlativing coefficient is 0.98, so frequency domain correlation coefficient is demonstrated by array received to signal truth.

Optionally, if relative coefficient is more than the first predetermined threshold value CFTH, then continue to determine the pulse sound letter of each passage Whether number length is more than the second predetermined threshold value, if the length of pulse sound signal is more than the second predetermined threshold value, it is believed that pulse sound is believed There is reverberation in number, be unsatisfactory for prerequisite, now need to carry out reverberation elimination.

The method that reverberation eliminates is particularly as follows: regard by reverberation space as a reverberation system as, and the pulse sound that sound source sends does Inputting for system, through reflecting to form the reverberation sound output as system, then this reverberation system model can be expressed as:

$x\left(t\right)=s\left(t\right)*h\left(t\right)+n\left(t\right)={\∫}_0^{\mathrm{\∞}}s(t-\mathrm{\τ})h\left(\mathrm{\τ}\right)d\mathrm{\τ}+n\left(t\right)---\left(5\right)$

In formula, h (t) represents the impulse response of reverberation system, and n (t) represents reverberation spatial environments noise, and s (t) represents arrival The sound source pulse sound in reverberation space, x (t) represents the reverberation sound of reverberation system output.

It will be seen that reverberation system impulse response and sound-source signal are convolution relation in time domain from above formula, want handle Reflected sound is removed from sound-source signal and must be untied this convolution relation, and convolution signal i.e. can linearly be divided by cepstrum technology From becoming additive signal, at cepstrum domain sound-source signal typically at low frequency, reflected signal is at high frequency, so carrying out low pass filtered at cepstrum domain After ripple, inverse transformation back signal i.e. can get dereverberation signal, and calculation procedure is as follows:

1.. the waveform of Detection and Extraction is carried out Complex Cepstrum Transform, and transformation for mula is as follows:

If the pulse sound sequence of time-domain samples of Detection and Extraction is x (k), k=1,2 ..., N, sequence length is N, enters sequence Row discrete Fourier transform:

$X\left(k\right)=\underset{j=1}{\overset{N}{\Σ}}x\left(j\right)e^{(-2\mathrm{\π}i)(j-1)(k-1)/N},i=\sqrt{-1},k=1,2,...,N---\left(6\right)$

Ask amplitude A (k) and the phase place of X (k)

In formula, real () represents the real part asking for complex signal, and imag () represents the imaginary part asking for complex signal, to phase place Income linearization process obtainsThen the cepstrum of x (k) is represented by:

2.. CX (k) is carried out low-pass filtering and obtains signal LCX (k)；

3.. LCX (k) is carried out the signal after cepstrum inverse transformation obtains dereverberationInverse transformation process and cepstrum Conversion process is omitted the most here.

Taking reverberation example for actual pulse sound as shown in figure 11, the most former reverb signal persistent period is relatively Long, after dereverberation, recovered original shorter pulse sound signal.

Optionally, however, it is determined that the pulse sound signal length of each passage is not more than the second predetermined threshold value, i.e. think that pulse sound is believed There is not reverberation in number, further determine that whether the signal to noise ratio of the pulse sound signal of each passage is more than the 3rd predetermined threshold value, if really The signal to noise ratio of the pulse sound signal of fixed each passage is more than the 3rd predetermined threshold value, then it is assumed that main energetic concentrates on limited in a frequency domain In the frequency range of bandwidth, i.e. meet prerequisite, may thereby determine that the pulse sound signal detected is target acoustic signal, this target Acoustical signal includes cannon sound, shot or explosive sound.

Wherein, the present embodiment use frequency domain signal to noise ratio carry out judging whether main energetic concentrates on limited band in a frequency domain In wide frequency range, definition frequency domain signal to noise ratio is as follows:

$FSNR=\frac{\underset{k=Lf}{\overset{Hf}{\Σ}}X\left(k\right)}{\underset{z=1}{\overset{N}{\Σ}}X\left(z\right)},z\∉\[Lf,Hf\]---\left(9\right)$

In formula, X (k) represents the discrete spectrum of the pulse sound extracted, and N represents discrete spectrum length, and Lf represents pulse sound Lower-frequency limit, Hf represents the upper frequency limit of pulse sound.When condition FSNR ＞ FSNRTH meets, final confirmation detects target arteries and veins Rush acoustical signal.

Step 107, meet prerequisite determining, and determine that the pulse sound signal of each passage detected is target pulse After acoustical signal, described target pulse acoustical signal is saved in caching, and records the start bit of described target pulse acoustical signal Put and end position, for the extraction carrying out target pulse acoustical signal according to described original position and described end position.

Step 108, after determining and being unsatisfactory for prerequisite, each channel pulse acoustical signal that will detect is removed, and lays equal stress on New execution step 101.

The method of a kind of pulse sound signal detection that the embodiment of the present invention provides, including to passage each in microphone array Pulse sound signal is sampled, and obtains the sampling acoustical signal of each passage, it is judged that whether there is strong background in this sampling acoustical signal and makes an uproar Sound, the most first carries out noise reduction process, then calculates the frame energy of this sampling acoustical signal after noise reduction process this sampling acoustical signal Amount；If it is not, the most directly calculate the frame energy of this sampling acoustical signal, according to frame energy and this sampling acoustical signal of this sampling acoustical signal Existence detect the pulse sound signal of each passage, relative to prior art, the embodiment of the present invention is at detection pulse sound letter Number time can carry out noise reduction process, can effectively get rid of the impact on testing result of the noise in environment, thus promote detection The probability of pulse sound signal and accuracy.

In the embodiment of the present invention embodiment of pulse sound signal supervisory instrument is described below.

Referring to Figure 12, in the embodiment of the present invention, the first embodiment of the detection device of pulse sound signal includes:

Sampling module 201, for sampling the pulse sound signal of passage each in microphone array, obtains each passage Sampling acoustical signal；

Judge module 202, is used for judging whether there is strong background noise, the most first to institute in described sampling acoustical signal State sampling acoustical signal and carry out noise reduction process, then calculate the frame energy of the described sampling acoustical signal after noise reduction process；If it is not, it is the most direct Calculate the frame energy of described sampling acoustical signal；

Optionally, in the present embodiment judge module 202 specifically for whether judging the time-domain signal of described sampling acoustical signal Exist periodically, the most then the time-domain signal of described sampling acoustical signal is carried out frequency domain transform, if obtaining there is harmonic relationships Line spectrum, then suppress the described line spectrum with harmonic relationships.

Detection module 203, for the frame energy according to described sampling acoustical signal and the existence of described sampling acoustical signal Detect the pulse sound signal of each passage.

Optionally, in the present embodiment, detection module 203 is specifically for being 0 or 1 when the existence of described sampling acoustical signal Time, if the frame energy of described sampling acoustical signal is more than the peak preset, it is determined that present sample acoustical signal is pulse sound signal, And present sample acoustical signal is put in the second caching, the initial point position of record present sample acoustical signal；

If the frame energy of described sampling acoustical signal is more than the intermediate value preset and less than the peak preset, it is determined that current Sampling acoustical signal is doubtful pulse sound signal, and re-executes step 1；

If the frame energy of described sampling acoustical signal is more than the minimum preset and less than the intermediate value preset, it is determined that current Sampling acoustical signal is noise, and re-executes step 1；

When the existence of described sampling acoustical signal is 2, if during the frame energy of described sampling acoustical signal is more than presetting Between be worth and less than the peak be located at, it is determined that present sample acoustical signal is pulse sound signal, and present sample acoustical signal is put Enter in caching；

If the frame energy of described sampling acoustical signal is more than the minimum preset and less than the intermediate value being located at, then record is current The end point position of sampling acoustical signal, and the initial point position and end point position calculation according to present sample acoustical signal go out currently The length of sampling acoustical signal；

When the existence of described sampling acoustical signal is 3, postpone according to the length of the present sample acoustical signal calculated Deposit middle extraction pulse sound signal.

Structural representation with reference to the second embodiment that Figure 13, Figure 13 are pulse sound of the present invention detection device.

First embodiment based on pulse sound signal supervisory instrument, this device also includes:

First determines module 204, for when meeting prerequisite, determines that the pulse sound signal of each passage detected is Target pulse acoustical signal.

Second determines module 205, and described second determines that module is used to determine whether to meet prerequisite, and described second determines Module is specifically for determining the relative coefficient of the pulse sound signal of any two passages in the pulse sound signal of each passage of detection Whether more than the first predetermined threshold value, if not, it is determined that be unsatisfactory for prerequisite；If, it is determined that the pulse sound signal of each passage Whether length is more than the second predetermined threshold value, if not, it is determined that be unsatisfactory for prerequisite；If, it is determined that the pulse sound of each passage Whether the signal to noise ratio of signal is more than the 3rd predetermined threshold value, if not, it is determined that be unsatisfactory for prerequisite, if, it is determined that meet pre- Put condition.

Preserving module 206, described target pulse sound, for after determining and meeting prerequisite, is believed by described preservation module Number it is saved in caching, and records original position and the end position of described target pulse acoustical signal, for according to described Beginning position and described end position carry out the extraction of target pulse acoustical signal；

Remove module 207, for after determining and being unsatisfactory for prerequisite, by clear for each channel pulse acoustical signal detected Remove.

The above, above example only in order to technical scheme to be described, is not intended to limit；Although with reference to front State embodiment the present invention has been described in detail, it will be understood by those within the art that: it still can be to front State the technical scheme described in each embodiment to modify, or wherein portion of techniques feature is carried out equivalent；And these Amendment or replacement, do not make the essence of appropriate technical solution depart from the spirit and scope of various embodiments of the present invention technical scheme.

Claims (12)

1. the detection method of a pulse sound signal, it is characterised in that comprise the steps:

Step 1: sample the pulse sound signal of passage each in microphone array, obtains the sampling acoustical signal of each passage；

Step 2: judge whether there is strong background noise in described sampling acoustical signal, the most described sampling acoustical signal is entered Row noise reduction process, then calculate the frame energy of the described sampling acoustical signal after noise reduction process；If it is not, the most directly calculate described sampling sound The frame energy of signal；

Step 3: detect each passage according to the frame energy of described sampling acoustical signal and the existence of described sampling acoustical signal Pulse sound signal.

Method the most according to claim 1, it is characterised in that at the frame energy according to described sampling acoustical signal with described adopt After the existence of sample acoustical signal detects the pulse sound signal of each passage, also include: when meeting prerequisite, determine inspection The pulse sound signal of each passage measured is target pulse acoustical signal.

Method the most according to claim 2, it is characterised in that described when meeting prerequisite, determines each of detection The pulse sound signal of passage is also to comprise determining whether to meet prerequisite before target pulse acoustical signal；

Described determine whether that meeting prerequisite includes:

Determine detection each passage pulse sound signal in the relative coefficient of pulse sound signal of any two passages whether be more than First predetermined threshold value, if not, it is determined that be unsatisfactory for prerequisite；If, it is determined that whether the pulse sound signal length of each passage More than the second predetermined threshold value, if, it is determined that it is unsatisfactory for prerequisite；If not, it is determined that the letter of the pulse sound signal of each passage Whether ratio of making an uproar is more than the 3rd predetermined threshold value, if not, it is determined that be unsatisfactory for prerequisite, if, it is determined that meet prerequisite.

Method the most according to claim 3, it is characterised in that described method also includes: when meeting prerequisite, really After the pulse sound signal of each passage that regular inspection is measured is target pulse acoustical signal, described target pulse acoustical signal is saved in slow In depositing, and record original position and the end position of described target pulse acoustical signal, for according to described original position and institute State end position and carry out the extraction of target pulse acoustical signal；

After determining and being unsatisfactory for prerequisite, each channel pulse acoustical signal that will detect is removed, and re-executes step 1.

Method the most according to claim 1, it is characterised in that described judge whether to exist in described sampling acoustical signal the strong back of the body Scape noise, the most first carries out noise reduction process to described sampling acoustical signal and includes:

Judge whether the time-domain signal of described sampling acoustical signal exists periodically, the most then the time domain to described sampling acoustical signal Signal carries out frequency domain transform, if obtaining the line spectrum with harmonic relationships, then suppresses the described line spectrum with harmonic relationships.

6. want the method described in 1 according to right, it is characterised in that the described frame energy according to described sampling acoustical signal and described adopt The existence of sample acoustical signal detects that the pulse sound signal of each passage includes:

When the existence of described sampling acoustical signal is 0 or 1, if the frame energy of described sampling acoustical signal is the highest more than preset Value, it is determined that present sample acoustical signal is pulse sound signal, and present sample acoustical signal is put in the second caching, record is current The initial point position of sampling acoustical signal；

If the frame energy of described sampling acoustical signal is more than the intermediate value preset and less than the peak preset, it is determined that present sample Acoustical signal is doubtful pulse sound signal, and re-executes step 1；

If the frame energy of described sampling acoustical signal is more than the minimum preset and less than the intermediate value preset, it is determined that present sample Acoustical signal is noise, and re-executes step 1；

When the existence of described sampling acoustical signal is 2, if the frame energy of described sampling acoustical signal is more than the intermediate value preset And less than the peak being located at, it is determined that present sample acoustical signal is pulse sound signal, and present sample acoustical signal is put into slow In depositing；

If the frame energy of described sampling acoustical signal is more than the minimum preset and less than the intermediate value being located at, then record present sample The end point position of acoustical signal, and the initial point position and end point position calculation according to present sample acoustical signal go out present sample The length of acoustical signal；

When the existence of described sampling acoustical signal is 3, according to the length of the present sample acoustical signal calculated from caching Extract pulse sound signal.

7. the detection device of a pulse sound signal, it is characterised in that including:

Sampling module, for sampling the pulse sound signal of passage each in microphone array, obtains the sampling sound of each passage Signal；

Judge module, is used for judging whether there is strong background noise in described sampling acoustical signal, the most first to described sampling sound Signal carries out noise reduction process, then calculates the frame energy of the described sampling acoustical signal after noise reduction process；If it is not, the most directly calculate described The frame energy of sampling acoustical signal；

Detection module, for detecting respectively according to the frame energy of described sampling acoustical signal and the existence of described sampling acoustical signal The pulse sound signal of passage.

Device the most according to claim 7, it is characterised in that described device also includes that first determines module, described first Determine module, for when meeting prerequisite, determine that the pulse sound signal of each passage detected is target pulse acoustical signal.

Device the most according to claim 8, it is characterised in that described device also includes that second determines module, described second Determining that module is used to determine whether to meet prerequisite, described second determines that module is specifically for determining the arteries and veins of each passage of detection Rush whether the relative coefficient of the pulse sound signal of any two passages in acoustical signal is more than the first predetermined threshold value, if not, it is determined that It is unsatisfactory for prerequisite；If, it is determined that whether the pulse sound signal length of each passage is more than the second predetermined threshold value, if it is not, then Determine and be unsatisfactory for prerequisite；If, it is determined that whether the signal to noise ratio of the pulse sound signal of each passage is more than the 3rd predetermined threshold value, If not, it is determined that be unsatisfactory for prerequisite, if, it is determined that meet prerequisite.

Device the most according to claim 9, it is characterised in that described device also includes preserving module and removing module, institute State preservation module for, after determining and meeting prerequisite, described target pulse acoustical signal being saved in caching, and record The original position of described target pulse acoustical signal and end position, enter for according to described original position and described end position The extraction of row target pulse acoustical signal；Described removing module is for after determining and being unsatisfactory for prerequisite, each by detect Channel pulse acoustical signal is removed.

11. devices according to claim 7, it is characterised in that described judge module is specifically for judging described sampling sound Whether the time-domain signal of signal exists periodically, the most then the time-domain signal of described sampling acoustical signal is carried out frequency domain transform, if Obtain the line spectrum with harmonic relationships, then the described line spectrum with harmonic relationships is suppressed.

12. devices according to claim 7, it is characterised in that described detection module specifically for:

When the existence of described sampling acoustical signal is 0 or 1, if the frame energy of described sampling acoustical signal is the highest more than preset Value, it is determined that present sample acoustical signal is pulse sound signal, and present sample acoustical signal is put in the second caching, record is current The initial point position of sampling acoustical signal；

If the frame energy of described sampling acoustical signal is more than the intermediate value preset and less than the peak preset, it is determined that present sample Acoustical signal is doubtful pulse sound signal, and re-executes step 1；

If the frame energy of described sampling acoustical signal is more than the minimum preset and less than the intermediate value preset, it is determined that present sample Acoustical signal is noise, and re-executes step 1；

When the existence of described sampling acoustical signal is 2, if the frame energy of described sampling acoustical signal is more than the intermediate value preset And less than the peak being located at, it is determined that present sample acoustical signal is pulse sound signal, and present sample acoustical signal is put into slow In depositing；

If the frame energy of described sampling acoustical signal is more than the minimum preset and less than the intermediate value being located at, then record present sample The end point position of acoustical signal, and the initial point position and end point position calculation according to present sample acoustical signal go out present sample The length of acoustical signal；

When the existence of described sampling acoustical signal is 3, according to the length of the present sample acoustical signal calculated from caching Extract pulse sound signal.