CN102520436A - Carrier resonance receiving type water target detection device - Google Patents

Abstract

The invention discloses a carrier resonance receiving type water target detection device, which comprises a receiver, a signal conditioning circuit, a signal processor and a power supply manager, wherein the receiver, the signal conditioning circuit and the signal processor are connected together sequentially; and the power supply manager is respectively connected with the receiver, the signal conditioning circuit and the signal processor. According to the carrier resonance receiving type water target detection device, a target is detected through sensing a forced resonance signal generated by a carrier under being excitated by a target radiation noise by adopting a manner of arranging an accelerometer on the inner wall of a housing inside the carrier, and a target motion parameter is resolved, and demands on the aspects of underwater guard, self protection and the like of an underwater carrier are met; and the accelerometer is attached on the inner wall of the housing for receiving the forced resonance signal without being in contact with an external medium, thus the carrier resonance receiving type water target detection device has the advantages of shock resistance, compression and corrosion resistance, flexibility and convenience in an installation mode.

Description

Object detecting device in a kind of carrier resonance receiving type water

Technical field

The present invention relates to target detection technique field in the water, relate in particular to object detecting device in a kind of carrier resonance receiving type water.

Background technology

Because sound wave has good propagation characteristic in water; Object detecting device is underwater sound equipment basically in water of being carried such as (like subsurface buoy) therefore at present under water on the carrier; Its transducer need be installed in hull outside; Contact and install additional kuppe with aqueous medium, and then link to each other with the electronic device that is installed in enclosure interior through lead.It is very high that the weak point of this transducer mounting means and side connecting conductor formula is that the watertightness performance to housing requires, and increased design difficulty; And transducer is prone to be corroded or marine growth adheres to, and damage easily, performance reduce even lost efficacy under the situation that receives outside thump.In addition, in some cases, can kuppe be installed in the transducer outside, but the kuppe material is difficult to satisfy simultaneously mechanical property, the design of stream shape and acoustics performance requirement, and is not easy to install.

Summary of the invention

The objective of the invention is for object detecting device in a kind of carrier resonance receiving type water is provided; With carrier under water as the wet end section that receives; Be employed in carrier inside and invest the mode that inner walls is installed accelerometer, the urgent resonance signal that receives that under the target radiated noise excitation, is produced through the perception carrier detects target, and calculates the parameters of target motion; The demand of aspects such as satisfied carrier is under water guarded against under water, self-protection, and avoided the problems referred to above and difficulty effectively.

The objective of the invention is to realize through following technical proposals:

This device comprises and the present invention includes receiver, signal conditioning circuit, signal processor and power supervisor; Wherein receiver, signal conditioning circuit link to each other and link to each other with signal processor order successively, and power supervisor links to each other respectively with receiver, signal conditioning circuit, signal processor;

Said power supervisor provides stabilized voltage supply for this device;

Said receiver comprises a pair of accelerometer in order to received vector forced vibration signal, is symmetrical in the carrier axis with the mode of subtend adhesion and is installed on the main casing inwall of carrier, and output two-way carrier forced vibration signal is given signal conditioning circuit;

Said signal conditioning circuit, with amplifying the also processing of filter away high frequency noise after the two-way carrier forced vibration signal stack that receives, the carrier forced vibration signal s (t) after output is handled gives signal processor;

Carrier forced vibration signal s (t) after said signal processor is handled signal conditioning circuit resolves, and calculates speed, distance abeam and the beam moment of target;

The concrete grammar that resolves is following:

Step 1:, adopt fast Fourier transform (FFT) to transform to frequency domain with the carrier forced vibration signal s (t) after the signal conditioning circuit processing;

Step 2: do the selection at frequency domain resonance spectrum peak through dichotomy, obtain resonance spectrum peak value P (f) and respective frequencies f thereof _P, utilize f _PObtain the corresponding frequency variance of resonance spectrum peak value

When satisfying condition

And during P (f)＞β, make the judgement of " detecting target occurs ", connect step 3; Otherwise then return step 1 up to adjudicating to till having target to occur; Wherein, α and β are respectively the fixed thresholds that presets;

Step 3: to the carrier forced vibration signal s (t) in the setting-up time section before the current time t; Adopt the short time discrete Fourier transform method; Slide and estimate the instantaneous frequency of resonance spectrum peak value; Each sliding time is exported a result at interval, obtains the sequence

of the instantaneous frequency at one group of resonance spectrum peak of surveying at last

Step 4: with predefined target velocity, distance abeam and the beam parameter priori space that span constituted constantly, equally spaced being divided into a plurality of grids, is cost function with formula (1), the pairing one group of parameter (v of each grid then ₀, R ₀, t ₀) the corresponding cost function value Φ (R of difference substitution formula (1) calculating ₀, v ₀, t ₀):

$\mathrm{\Φ}(R_0,v_0,t_0)=$

$E<{\left\{\right[1+\frac{v_0^2\left({t-t}_0\right)}{c\sqrt{R_0^2+v_0^2{\left({t-t}_0\right)}^2}}]\hat{f}\left(t\right)-E<[1+\frac{v_0^2\left({t-t}_0\right)}{c\sqrt{R_0^2+v_0^2{\left({t-t}_0\right)}^2}}]\hat{f}\left(t\right)>\}}^2>---\left(1\right)$

v ₀, R ₀, t ₀The target velocity of respectively corresponding each grid, distance abeam and beam are constantly; C is the velocity of sound in this device place medium; E<>expression is with sequence

In each element Calculate the series of computation result in the substitution<>, then result of calculation is asked average;

Step 5: compare the pairing cost function value of each grid, get the estimated result of one group of corresponding parameter of minimum value as current time t;

Step 6: return step 3; Estimate the new pairing instantaneous frequency in resonance spectrum peak constantly; Adopt in the instantaneous frequency replacement resonance spectrum peak frequency sequence

at resonance spectrum peak in this new moment the earliest the instantaneous frequency at resonance spectrum peak constantly; And repeating step four to five that is directed against after upgrading calculates the parameter estimation result in the new moment; In circulation execution in step three in step 5; The device step that whether judgement has target to occur in execution in step two always; And when making the judgement of " driftlessness appearance ", withdraw from the circulation of step 3～step 5.

Beneficial effect of the present invention:

This device under water carrier as the wet end section that receives; Be employed in carrier inside and invest the mode that inner walls is installed accelerometer; The urgent resonance signal that receives that under the target radiated noise excitation, is produced through the perception carrier detects target; And calculate the parameters of target motion, the demand of aspects such as satisfied carrier is under water guarded against under water, self-protection.

2. accelerometer of the present invention invests the inner walls reception and needn't contact external agency, shock resistance, withstand voltage corrosion-resistant, mounting means flexible and convenient.

3. the present invention adopts low-power consumption, modular design, and volume is little, in light weight, utonomous working for a long time.

Description of drawings

Fig. 1 is a structural representation block diagram of the present invention.

Fig. 2 is the installation site synoptic diagram of accelerometer.

Fig. 3 is the signal processing flow figure of object detecting device in the carrier resonance receiving type water.

Embodiment

In order to understand technical scheme of the present invention better, below in conjunction with accompanying drawing and specific embodiment the present invention is done to describe in further detail.

As shown in Figure 1: this device comprises and the present invention includes receiver, signal conditioning circuit, signal processor and power supervisor; Wherein receiver, signal conditioning circuit link to each other and link to each other with signal processor order successively, and power supervisor links to each other respectively with receiver, signal conditioning circuit, signal processor;

This device is equipped on the carrier as shown in Figure 2; Said receiver comprises a pair of accelerometer in order to received vector forced vibration signal; Be symmetrical in the carrier axis with the mode of subtend adhesion and be installed on the main casing inwall of carrier, output two-way carrier forced vibration signal s (t) gives signal conditioning circuit; Wherein, the line between the two sensors installation site is the z axle, and the carrier axis is the x axle, and the two is vertical each other, constitutes a three-dimensional system of coordinate with the y axle, and O is an initial point.The receiving side signal formula of said receiver be with carrier as the wet end section that receives, to be carrier received urgent resonance signal what the target radiated noise excitation produced down for institute's perception and the signal that is used.

Said power supervisor provides stabilized voltage supply for this device;

Said signal conditioning circuit, with amplifying the also processing of filter away high frequency noise after the two-way carrier forced vibration signal stack that receives, the carrier forced vibration signal s (t) after output is handled gives signal processor;

Carrier forced vibration signal s (t) after said signal processor is handled signal conditioning circuit resolves, and calculates speed, distance abeam and the beam moment of target; The concrete grammar that resolves such as Fig. 3:

Step 1:, adopt fast Fourier transform (FFT) to transform to frequency domain with the carrier forced vibration signal s (t) after the signal conditioning circuit processing;

Step 2: do the selection at frequency domain resonance spectrum peak through dichotomy, obtain resonance spectrum peak value P (f) and respective frequencies f thereof _P, utilize f _PObtain the corresponding frequency variance of resonance spectrum peak value

When satisfying condition

And during P (f)＞β, make the judgement of " detecting target occurs ", connect step 3; Otherwise then return step 1 up to adjudicating to till having target to occur; Wherein, α and β are respectively the fixed thresholds that presets;

Step 3: to the carrier forced vibration signal s (t) in the setting-up time section before the current time t; Adopt the short time discrete Fourier transform method; Slide and estimate the instantaneous frequency of resonance spectrum peak value; Each sliding time is exported a result at interval, obtains the sequence

of the instantaneous frequency at one group of resonance spectrum peak of surveying at last

Step 4: with predefined target velocity, distance abeam and the beam parameter priori space that span constituted constantly, equally spaced being divided into a plurality of grids, is cost function with formula (1), the pairing one group of parameter (v of each grid then ₀, R ₀, t ₀) the corresponding cost function value Φ (R of difference substitution formula (1) calculating ₀, v ₀, t ₀):

$\mathrm{\&Phi;}(R_0,v_0,t_0)=$

$E<{\left\{\right[1+\frac{v_0^2\left({t-t}_0\right)}{c\sqrt{R_0^2+v_0^2{\left({t-t}_0\right)}^2}}]\hat{f}\left(t\right)-E<[1+\frac{v_0^2\left({t-t}_0\right)}{c\sqrt{R_0^2+v_0^2{\left({t-t}_0\right)}^2}}]\hat{f}\left(t\right)>\}}^2>---\left(1\right)$

v ₀, R ₀, t ₀The target velocity of respectively corresponding each grid, distance abeam and beam are constantly; C is the velocity of sound in this device place medium; E<>expression is with sequence

In each element Calculate the series of computation result in the substitution<>, then result of calculation is asked average;

Step 5: compare the pairing cost function value of each grid, get the estimated result of one group of corresponding parameter of minimum value as current time t;

Step 6: return step 3; Estimate the new pairing instantaneous frequency in resonance spectrum peak constantly; Adopt in the instantaneous frequency replacement resonance spectrum peak frequency sequence

at resonance spectrum peak in this new moment the earliest the instantaneous frequency at resonance spectrum peak constantly; And

repeating step four to five that is directed against after upgrading calculates the parameter estimation result in the new moment; In circulation execution in step three in step 5; The device step that whether judgement has target to occur in execution in step two always; And when making the judgement of " driftlessness appearance ", withdraw from the circulation of step 3～step 5.

Wherein the derivation of cost function is following:

To centre frequency is f ₀Target because Doppler shift, t arbitrarily constantly the theoretical value of resonance spectrum peak frequency f (t) satisfy:

$f\left(t\right)={[1+\frac{v_0^2\left({t-t}_0\right)}{c\sqrt{R_0^2+v_0^2{\left({t-t}_0\right)}^2}}]}^{-1}{f}_0---\left(1^{,}\right)$

Wherein, c is the velocity of sound in this device place medium.Disturb if further contemplate diversity of settings, then should satisfy following relation between the resonance spectrum peak frequency

of actual measurement and its measuring error e (t):

$\hat{f}\left(t\right)={[1+\frac{v_0^2\left({t-t}_0\right)}{c\sqrt{R_0^2+v_0^2{\left({t-t}_0\right)}^2}}]}^{-1}{f}_0+e\left(t\right)---\left(2\right)$

Wherein, centre frequency f ₀Be a constant, the resonance spectrum peak frequency of measuring error e (t) and actual measurement It all is stochastic variable.Can get f by following formula ₀The expression formula that satisfies:

$f_0=[1+\frac{v_0^2\left({t-t}_0\right)}{c\sqrt{R_0^2+v_0^2{\left({t-t}_0\right)}^2}}][\hat{f}\left(t\right)-e\left(t\right)]---\left(3\right)$

Suppose that resonance spectrum peak frequency error measurement e (t) satisfies the Gaussian distribution of 0 average, so respectively average statistical being got on formula (3) both sides can get:

$f_0=E<{\hat{f}}_0\left(t\right)>=E<[1+\frac{v_0^2\left({t-t}_0\right)}{c\sqrt{R_0^2+v_0^2{\left({t-t}_0\right)}^2}}]\hat{f}\left(t\right)>---\left(4\right)$

Wherein, E <>express time is average.Formula (4) shows: if parameters R ₀, v ₀And t ₀Known, then in a certain amount of time, by the resonance spectrum peak frequency of receiving hydrophone actual measurement

Directly substitution Doppler shift relational expression (1 ') can estimate to obtain a centre frequency sequence

The average of this sequence just equals the true value f of target's center's frequency ₀, and the variance of this sequence can be written as:

$\mathrm{\&Phi;}(R_0,v_0,t_0)=$

$E<{\left\{\right[1+\frac{v_0^2\left({t-t}_0\right)}{c\sqrt{R_0^2+v_0^2{\left({t-t}_0\right)}^2}}]\hat{f}\left(t\right)-E<[1+\frac{v_0^2\left({t-t}_0\right)}{c\sqrt{R_0^2+v_0^2{\left({t-t}_0\right)}^2}}]\hat{f}\left(t\right)>\}}^2>---\left(1\right)$

In principle, has only parameters R in formula (5) ₀, v ₀And t ₀When getting their true value respectively, variance Φ (R ₀, v ₀, t ₀) just get minimum value.Therefore, can estimate to obtain the kinematic parameter of target through minimizing following formula.

To accomplishing the carrier of different mission tasks, parameters of target motion estimated result can be exported to the control system or the data recording equipment storage of carrier as requested.

In sum, more than being merely preferred embodiment of the present invention, is not to be used to limit protection scope of the present invention.All within spirit of the present invention and principle, any modification of being done, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.

Claims (1)

1. object detecting device in the carrier resonance receiving type water is characterized in that, this device comprises and the present invention includes receiver, signal conditioning circuit, signal processor and power supervisor; Wherein receiver, signal conditioning circuit link to each other and link to each other with signal processor order successively, and power supervisor links to each other respectively with receiver, signal conditioning circuit, signal processor;

Said power supervisor is used to this device stabilized voltage supply is provided;

Said receiver comprises a pair of accelerometer in order to received vector forced vibration signal, is symmetrical in the carrier axis with the mode of subtend adhesion and is installed on the main casing inwall of carrier, and output two-way carrier forced vibration signal is given signal conditioning circuit;

Said signal conditioning circuit, with amplifying the also processing of filter away high frequency noise after the two-way carrier forced vibration signal stack that receives, the carrier forced vibration signal s (t) after output is handled gives signal processor;

Carrier forced vibration signal s (t) after said signal processor is handled signal conditioning circuit resolves, and calculates speed, distance abeam and the beam moment of target;

The concrete grammar that resolves is following:

Step 1:, adopt fast Fourier transform (FFT) to transform to frequency domain with the carrier forced vibration signal s (t) after the signal conditioning circuit processing;

Step 2: do the selection at frequency domain resonance spectrum peak through dichotomy, obtain resonance spectrum peak value P (f) and respective frequencies f thereof _P, utilize f _PObtain the corresponding frequency variance of resonance spectrum peak value

When satisfying condition And during P (f)＞β, make the judgement of " detecting target occurs ", connect step 3; Otherwise then return step 1 up to adjudicating to till having target to occur; Wherein, α and β are respectively the fixed thresholds that presets;

Step 3: to the carrier forced vibration signal s (t) in the setting-up time section before the current time t; Adopt the short time discrete Fourier transform method; Slide and estimate the instantaneous frequency of resonance spectrum peak value; Each sliding time is exported a result at interval, obtains the sequence

of the instantaneous frequency at one group of resonance spectrum peak of surveying at last

Step 4: with predefined target velocity, distance abeam and the beam parameter priori space that span constituted constantly, equally spaced being divided into a plurality of grids, is cost function with formula (1), the pairing one group of parameter (v of each grid then ₀, R ₀, t ₀) the corresponding cost function value Φ (R of difference substitution formula (1) calculating ₀, v ₀, t ₀):

$\mathrm{\&Phi;}(R_0,v_0,t_0)=$

$E<{\left\{\right[1+\frac{v_0^2\left({t-t}_0\right)}{c\sqrt{R_0^2+v_0^2{\left({t-t}_0\right)}^2}}]\hat{f}\left(t\right)-E<[1+\frac{v_0^2\left({t-t}_0\right)}{c\sqrt{R_0^2+v_0^2{\left({t-t}_0\right)}^2}}]\hat{f}\left(t\right)>\}}^2>---\left(1\right)$

v ₀, R ₀, t ₀The target velocity of respectively corresponding each grid, distance abeam and beam are constantly; C is the velocity of sound in this device place medium; E<>expression is with sequence

In each element Calculate the series of computation result in the substitution<>, then result of calculation is asked average;

Step 5: compare the pairing cost function value of each grid, get the estimated result of one group of corresponding parameter of minimum value as current time t;

Step 6: return step 3; Estimate the new pairing instantaneous frequency in resonance spectrum peak constantly; Adopt in the instantaneous frequency replacement resonance spectrum peak frequency sequence at resonance spectrum peak in this new moment the earliest the instantaneous frequency at resonance spectrum peak constantly; And

repeating step four to five that is directed against after upgrading calculates the parameter estimation result in the new moment; In circulation execution in step three in step 5; The device step that whether judgement has target to occur in execution in step two always; And when making the judgement of " driftlessness appearance ", withdraw from the circulation of step 3～step 5.

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