CN104122544B - A kind of counteracting method dragging the linear array big interference source of sonar constant bearing and system - Google Patents

Abstract

The present invention proposes a kind of counteracting method dragging the linear array big interference source of sonar constant bearing and system, and described method comprises: step 101) signal dragging linear array array element to receive is carried out beam shaping process obtain θ_iWave beam B corresponding in orientation_iBeam Domain signal；Step 102) use reconstruction strategy to obtain θ according to Beam Domain signal_iInterference in orientation produces the time-domain signal of interference in each array element；Step 103) by the signal of actual for each array element reception respectively with described θ_iThe time-domain signal that interference in orientation produces interference in each array element is poor, obtains counteracting θ_iThe signal of each array element of orientation interference；Step 104) to another orientation θ_jOn interference repeat the above steps, until offset from each orientation interference the signal each array element on dragging linear array actual receive signal impact.Described reconstruction strategy is: to drag in linear array on the basis of zero array element, and according to the amount of delay of each array element, the Beam Domain signal of interference place wave beam is carried out Attack delay.

Description

A kind of counteracting method dragging the linear array big interference source of sonar constant bearing and system

Technical field

The present invention relates to the interference mitigation technology in Array Signal Processing, drag linear array sonar constant bearing particularly to one The counteracting method of big interference source and system.

Background technology

Drag linear array sonar owing to away from tow platform, the shipself noise being subject to interference is relatively small, thus is commonly used for detection Weak target in the water such as submarine.But, in actual working environment, it is usually present the strong targets such as large-tonnage surface vessel, these Target radiated noise level is high, can be substantially reduced the reception letter dragging linear array sonar for weak target when being present in same marine site Make an uproar ratio, finally cause the biggest difficulty to target detection.

At present, there is more systematic research for this counteracting method dragging linear array sonar shipself noise, equipment Using the methods such as adaptive noise cancellations in, its core is to use interfering beam output each to offset as its reference input more Interference in array element.But in the actual application of sonar system, it has been found that, shipself noise is far from unique high sound source Level interference source, the detection to weak target equally of the radiated noise of large surface warship produces a very large impact.But, surface vessel The orientation of target is random, and as a target, if need to be cancelled, need sonar user according to on-the-spot actual feelings Condition determines.Therefore, great majority can not be completely suitable for offsetting fixing big target for the adaptive algorithm offsetting shipself noise Interference, it is difficult to meet actual application demand.

Summary of the invention

It is an object of the invention to offset the radiated noise of big for the constant bearing occurred in the range of sonar detection target, To improve the received signal to noise ratio of the system weak target to needing detection, i.e. the invention provides one and drag the fixing side of linear array sonar The counteracting method of the big interference source in position and system.

For achieving the above object, the invention provides a kind of counteracting method dragging the linear array big interference source of sonar constant bearing, Described method comprises:

Step 101) signal dragging linear array array element to receive carried out beam shaping process and obtain θ_iWave beam B corresponding in orientation_i Beam Domain signal；

Wherein, B_iNumber for labelling wave beam, and θ_iAzimuth for the big interference source of known existence；

Step 102) use reconstruction strategy to obtain θ according to Beam Domain signal_iInterference in orientation produces dry in each array element The time-domain signal disturbed；

Step 103) by the signal of actual for each array element reception respectively with described θ_iInterference in orientation is produced in each array element The time-domain signal of raw interference is poor, obtains counteracting θ_iThe signal of each array element of orientation interference；

Step 104) to another orientation θ_jOn interference repeat the above steps, until offsetting from the interference signal in each orientation The impact that receive signal actual on each array element dragging linear array.

When each array element dragging linear array is equally spaced line array, step 101) described in beam shaping be processed as: will drag On the basis of zero array element in linear array, the Element space signal receiving N number of array element uses equation below to implement at time delay summation Reason:

$y_{B_i}\left(t\right)=\frac{1}{N}\underset{n=0}{\overset{N-1}{\mathrm{\Σ}}}{x}_n[t-\mathrm{n\τ}\left({\mathrm{\θ}}_i\right)],$

Wherein,It is from θ_iThe time delay that the signal in direction is corresponding in the n-th array element；N= 0,1,…,N-1；D is array element distance；C is the velocity of sound in water；θ is obtained after processing for beam shaping_iBeam Domain in orientation Signal；B_iFor waiting to offset the wave beam number that interference orientation, place is corresponding.

Above-mentioned reconstruction strategy is: to drag in linear array on the basis of zero array element, by the Beam Domain signal of interference place wave beam Carrying out Attack delay according to the amount of delay of each array element, concrete formula is as follows:

$u_n\left(t\right)=y_{B_i}[t+\mathrm{n\τ}\left({\mathrm{\θ}}_i\right)]$

Wherein,It it is orientation θ that there is interference source_iSignal on direction is in the n-th array element Corresponding time delay；N=0,1 ..., N-1；D is array element distance；C is the velocity of sound in water；u_nT () is from orientation θ_iInterference on direction The interference signal that n-th array element is produced.

Above-mentioned steps 103) use equation below obtain offset interference after array element receive signal:

x′_n(t)=x_n(t)-u_n(t), n=0,1 ..., N-1

Wherein, x_nT () is the signal that current time each array element actual acquisition arrives, u_nT () is to utilize Beam Domain signal through pre- The Element space signal of the interference that Delay reconstruction obtains, x '_nT () is the new Element space signal obtained after Interference Cancellation.

In order to realize said method, present invention also offers a kind of counteracting system dragging the linear array big interference source of sonar constant bearing System, it is characterised in that described system comprises:

Big interference source orientation acquisition module, for extracting the azimuth information that there is big interference source from reception signal；

Interfering beam territory, orientation signal acquisition module, for the reception signal of each array element is carried out beam shaping process, Obtain the Beam Domain signal of the big interference source correspondence wave beam in certain orientation；

Element space interference signal acquisition module, for using reconstruction strategy to obtain the interference in certain orientation based on Beam Domain signal The source interference signal to each array element signals；

Interference cancellation module, for array element signals that reconstruct is obtained from each array element actual acquisition to signal deduct, Obtain the Element space signal eliminating a certain interference；

Judge module, for judging whether that all azimuths by big interference source orientation acquisition module obtains all are done Disturb elimination, if it is not, the signal that interference cancellation module exports is re-entered interfering beam territory, orientation signal acquisition module Carry out eliminating, until all interference are all eliminated for the interference in certain orientation with interference cancellation module.

Interfering beam territory, above-mentioned orientation signal acquisition module comprises further:

Element space signal acquisition submodule, for extract each array element receive signal or obtain through interference eliminate after each The signal that array element receives；

First processes submodule, for being deposited based on certain by the Element space signal that each Element space signal acquisition submodule obtains Orientation angles at big interference source carries out time delay processing, and wherein said time delay is respectively from the signal in certain big interference source direction Time delay corresponding in individual array element；

Second processes submodule, and the signal after the first process submodule for each array element being exported processes is sued for peace, Beam Domain signal to the big interference source correspondence wave beam in certain orientation.

Above-mentioned interference signal acquisition module uses the reconstruct of Attack delay strategy from the interference source signal in certain orientation to each The interference signal of array element, wherein, described Attack delay is the signal correspondence in each array element from certain big interference source direction Time delay.

Compared with prior art, the present invention's it is a technical advantage that: the present invention provide method be applicable to drag linear array sonar The counteracting of big interference source present on any direction in investigative range, can cascade use the method, and every by setting flexibly One-level offsets jamming bearing corresponding to computing, reaches to offset the purpose of the big interference source of all constant bearings in investigative range.With Simple shipself noise counteracting method is compared, and the method has higher motility, and neutralization effect can extend to more interference Source.Meanwhile, it is important to note that the method is equally applicable to simple shipself noise counteracting work, cascade uses the party Method, can balance out direct sound wave and each road reflected sound of shipself noise well.

Accompanying drawing explanation

Fig. 1 is a preferred embodiment of the invention, and cascade uses the present invention to offset the strongly disturbing flow process in both direction.

Detailed description of the invention

Below in conjunction with the accompanying drawings technical scheme is described in detail explanation.

The technical scheme that the present invention takes, utilizes the signal of big target jamming place wave beam, reconstructs what this target was formed Element space interference signal, and this interference signal is directly deducted from Element space, the final counteracting realizing interference.When to drag linear array In on the basis of No. 0 array element time, its step is as follows:

1) the time-domain signal x to the N number of array element obtained_n(t), n=0,1 ..., N-1, implements at time domain routine beam shaping Reason (CBF), obtains disturbing orientation θ, place_iCorresponding wave beam B_iTime-domain signalWherein, θ_i It is signal incident direction and the angle dragging linear array normal；It is θ_iThe signal in direction is right in the n-th array element The time delay answered；N=0,1 ..., N-1；D is array element distance；C is the velocity of sound in water.

2) the wave beam time-domain signal to step 1) outputImplement Element space signal reconstruction, it is thus achieved that wave beam B_iCorresponding θ_i The time-domain signal that interference on direction produces in each array elementWherein,It is θ_iThe time delay that the signal in direction is corresponding in the n-th array element；N=0,1 ..., N-1；D is array element distance；C is the velocity of sound in water；

3) by step 2) signal that generates in each array element of the interference that obtains deducts from the signal that each array element receives, obtains Do not comprise the Element space signal x ' of interference signal_n(t)=x_n(t)-u_n(t), n=0,1 ..., N-1；

4) if also having other interference to need to offset, then with x '_nT () replaces former Element space signal x_n(t), repeat the above steps 1) to 3), until the interference in all orientation is all cancelled completely；The Element space signal note obtained after all interference are all cancelled For xx_n(t), n=0,1 ..., N-1, to xx_nT () carries out conventional beam shaping and processes, can obtain azimuth information, and this orientation is believed In breath, do not include the interference being canceled out, xx_nT () can be additionally used in other sonar system signal processing computing.

Above-mentioned steps 1) to drag in linear array on the basis of the 0th array element, the time-domain signal x to N number of array element_nT () implements " time delay-ask With " time domain routine beam shaping process, calculate B_iThe beam signal of individual wave beam $y_{B_i}\left(t\right)=\frac{1}{N}\underset{n=0}{\overset{N-1}{\mathrm{\Σ}}}{x}_n[t-\mathrm{n\τ}\left({\mathrm{\θ}}_i\right)],$ $\mathrm{n\τ}\left({\mathrm{\θ}}_i\right)=\frac{\mathrm{nd}\sin {\mathrm{\θ}}_i}{c}$ It is θ_iThe time delay that the signal in direction is corresponding in the n-th array element, n=0,1 ..., N-1, d are between array element Away from, c is the velocity of sound in water, lower same；

Above-mentioned steps 2) to step 1) output Beam Domain signal implement " Attack delay ", with reconstruct on this wave beam interference letter " contribution " number in each array element, is designated as

Above-mentioned steps 3) by step 2) interference reconstructed through " Attack delay " by Beam Domain signal that exports produces in each array element Raw signal deducts from the signal that each array element is an actually-received, and is designated as x '_n(t)=x_n(t)-u_n(t), n=0,1 ..., N-1, This is actually " contribution " having deducted this interference docking collection of letters number from each array element, makes no longer to comprise this in Element space signal The impact that interference causes, has reached the purpose of this Interference Cancellation；

Above-mentioned steps 4) by step 1) to 3) repetition, actually cascade uses this interference cancellation method, reaches The purpose of the multiple interference in counteracting different azimuth simultaneously.In the final Element space signal obtained, the most do not comprise all counteractings The impact of the interference fallen, therefore, sonar system carries out beam shaping etc. with this group Element space signal and processes, the result obtained Also the impact of the interference offset is foreclosed.

The spacing with array element number as N, between each array element line array as d is offset respectively at θ₁And θ₂Interference on direction is Example, is described in further detail the detailed description of the invention of the present invention.

Embodiment:

Step 201, if Element space signal is expressed as x_n(t) (wherein, n=0,1 ..., N-1, and N represents and receives the array element that comprises of battle array Total number), this signal should be the original array element signals that signal processing system receives.On the basis of No. 0 array element, then θ₁Direction pair The wave beam B answered₁Beam Domain signal should be expressed as $y_{B_1}\left(t\right)=\frac{1}{N}[x_0\left(t\right)+x_1(t-\mathrm{\τ}\left({\mathrm{\θ}}_1\right))+\·\·\·+x_{N=1}(t-(N-1)\mathrm{\τ}\left({\mathrm{\θ}}_1\right))],$ Wherein, $\mathrm{\τ}\left({\mathrm{\θ}}_1\right)=\frac{d\sin {\mathrm{\θ}}_1}{c},$ It is B₁Number unit time delay that wave beam is corresponding,Then represent B₁Number wave beam Time delay corresponding in the n-th array element, n=0,1 ..., N-1.

Step 202, utilizes the wave beam B tried to achieve in step 201₁Beam Domain signalReconstruct θ₁Interference on direction The time-domain signal produced in each array element, can realize reconstruct by the method for Attack delay.By θ₁Interference on direction is n-th The time-domain signal produced in array element is designated as u_n(t), thenSimilarly, haveTable Show B₁The time delay that number wave beam is corresponding in the n-th array element, n=0,1 ..., N-1；

Step 203, by the interference θ of reconstruct₁Corresponding array element signals deducts from the signal of each array element actual acquisition, will subtract The Element space signal after interference is gone to be designated as x '_n(t), n=0,1 ..., N-1, then x '_n(t)=x_n(t)-u_n(t), n= 0,1,…,N-1；

Now, if using x '_nT () carries out signal processing computing as the input of sonar system, it is thus achieved that azimuth information Etc. result will not comprise θ₁Interference on direction.

Step 204, by the x in step 201_nT () uses x '_nT () replaces, n=0, and 1 ..., N-1, θ₁Use θ₂Replace, B₁Use B₂ Replace (B₂For θ₂The wave beam that direction is corresponding), and repeat step 101 to 103, carry out beam shaping computing, it is thus achieved that wave beam B₂Ripple Bundle territory signalAnd thus reconstruct θ₂The Element space signal of the interference correspondence on direction? After Element space signal that this is disturbed from x '_nT () deducts, be designated as x "_n(t)=x '_n(t)-u′_n(t)。

Make xx_n(t)=x "_n(t), here it is the Element space signal obtained after having offset whole two interference, sonar system profit Complete the signal processing work such as beam shaping with this signal, the result obtained would not comprise the impact of the two interference, Add the signal to noise ratio of other echo signal.

It should be noted last that, above example is only in order to illustrate technical scheme and unrestricted.Although ginseng According to embodiment, the present invention is described in detail, it will be understood by those within the art that, the technical side to the present invention Case is modified or equivalent, and without departure from the spirit and scope of technical solution of the present invention, it all should be contained in the present invention Right in the middle of.

Claims (5)

1. dragging a counteracting method for the linear array big interference source of sonar constant bearing, described method comprises:

Step 101) signal dragging linear array array element to receive carried out beam shaping process and obtain θ_iWave beam B corresponding in orientation_iRipple Bundle territory signal；

Wherein, B_iNumber for labelling wave beam, and θ_iAzimuth for the big interference source of known existence；

Step 102) use reconstruction strategy to obtain θ according to Beam Domain signal_iInterference in orientation produce in each array element interference time Territory signal；

Step 103) by the signal of actual for each array element reception respectively with described θ_iInterference in orientation produces interference in each array element Time-domain signal poor, obtain counteracting θ_iThe signal of each array element of orientation interference；

Step 104) to another orientation θ_jOn interference repeat the above steps, until offsetting from the interference signal in each orientation dragging The actual impact receiving signal of each array element of linear array；

When being equally spaced line array when dragging linear array, step 101) described in beam shaping be processed as: the in linear array the 0th will be dragged On the basis of individual array element, the Element space signal receiving N number of array element uses equation below to implement time delay summation and processes:

$y_{B_i}\left(t\right)=\frac{1}{N}\underset{n=0}{\overset{N-1}{\Σ}}{x}_n\[t-n\mathrm{\τ}\left({\mathrm{\θ}}_i\right)\],$

Wherein,It is from θ_iThe time delay that the signal in direction is corresponding in the n-th array element；N=0, 1,…,N-1；D is array element distance；C is the velocity of sound in water；θ is obtained after processing for beam shaping_iBeam Domain letter in orientation Number；B_iFor waiting to offset the wave beam number that interference orientation, place is corresponding；x_nT () is the signal that current time each array element actual acquisition arrives.

The counteracting method dragging the linear array big interference source of sonar constant bearing the most according to claim 1, it is characterised in that described Reconstruction strategy is: to drag in linear array on the basis of zero array element, by the Beam Domain signal of interference place wave beam according to each array element Amount of delay carries out Attack delay, and concrete formula is as follows:

$u_n\left(t\right)=y_{B_i}[t+\mathrm{n\τ}\left({\mathrm{\θ}}_i\right)]$

Wherein,It it is orientation θ that there is interference source_iSignal on direction is correspondence in the n-th array element Time delay；N=0,1 ..., N-1；D is array element distance；C is the velocity of sound in water；u_nT () is from orientation θ_iInterference on direction is to n-th The interference signal that individual array element produces.

The counteracting method dragging the linear array big interference source of sonar constant bearing the most according to claim 1, it is characterised in that described Step 103) use equation below obtain offset interference after array element receive signal:

x′_n(t)=x_n(t)-u_n(t), n=0,1 ..., N-1

Wherein, x_nT () is the signal that current time each array element actual acquisition arrives, u_nT () is to utilize Beam Domain signal through Attack delay The Element space signal of the interference that reconstruct obtains, x '_nT () is the new Element space signal obtained after Interference Cancellation.

4. the bucking-out system dragging the linear array big interference source of sonar constant bearing, it is characterised in that described system comprises:

Big interference source orientation acquisition module, for extracting the azimuth information that there is big interference source from reception signal；

Interfering beam territory, orientation signal acquisition module, for the reception signal of each array element is carried out beam shaping process, obtains The Beam Domain signal of the big interference source correspondence wave beam in certain orientation；

Element space interference signal acquisition module, for using reconstruction strategy to obtain the interference source pair in certain orientation based on Beam Domain signal The interference signal of each array element signals；

Interference cancellation module, for array element signals that reconstruct is obtained interference signal from each array element actual acquisition to signal Deduct, it is thus achieved that eliminate the Element space signal of a certain interference；

Judge module, for judging whether that all azimuths obtained by big interference source orientation acquisition module have all carried out interference and disappeared Remove, if it is not, the signal that interference cancellation module exports is re-entered interfering beam territory, orientation signal acquisition module and does Disturb cancellation module to carry out eliminating, until all interference are all eliminated for the interference in certain orientation；Interfering beam territory, described orientation Signal acquisition module comprises further:

Element space signal acquisition submodule, for extracting signal or the acquisition each array element after interference eliminates that each array element receives The signal received；

First processes submodule, exists big based on certain for the Element space signal obtained by each Element space signal acquisition submodule The orientation angles of interference source carries out time delay processing, and wherein said time delay is in each battle array from the signal in certain big interference source direction Time delay corresponding in unit；

Second processes submodule, and the signal after the first process submodule for each array element being exported processes is sued for peace, and obtains certain The Beam Domain signal of the big interference source correspondence wave beam in individual orientation.

The bucking-out system dragging the linear array big interference source of sonar constant bearing the most according to claim 4, it is characterised in that described Element space interference signal acquisition module uses the reconstruct of Attack delay strategy from the interference source signal in certain orientation to each array element Interference signal, wherein, described Attack delay is the signal time delay of correspondence in each array element from certain big interference source direction.