CN104931955A - Method for compensating amplitude of emission signal of broadband sonar system - Google Patents

Abstract

The invention discloses a method for compensating the amplitude of an emission signal of a broadband sonar system. The method comprises the following steps that a sonar emission system emits an ideal chirp signal x0[n], and an ideal sonar reception system is used to collect a distorted chirp signal y[n] in a soundproofing water pool; an error function e[n] is constructed, an estimated value, which satisfies the condition of min{E[e2[n]]}, of a transfer function of a broadband matching network and an energy transducer is searched, and a transfer function w[n] of an amplitude compensator is obtained; the amplitude compensator adjusts the amplitude of the ideal chirp signal; the power of the adjusted chirp signal is amplified; the power-amplified chirp signal is output to the energy transducer via the broadband matching network; the energy transducer converts an electrical signal into an acoustic signal and radiates the acoustic signal to water; and the ideal sonar reception system is used to collect the acoustic signal emitted by the energy transducer in the soundproofing water pool. The method can be used to reduce amplitude distortion of the emission signal, and has the advantage of high precision.

Description

A kind of compensating wide band Sonar system transmits the method for amplitude

Technical field

The invention belongs to Sonar Signal and launch field, particularly relate to a kind of compensating wide band Sonar system and to transmit the method for amplitude.

Background technology

In the design of broadband Sonar system, wide-band transducer is the important component part of emission coefficient.The transmitting voltage response of usual transducer in bandwidth rises and falls within 3dB, but transmitting voltage response rises and falls at 5 ~ 10dB in some wide-band transducers, and when broadband signal launched by transducer, the acoustical signal of launching will produce amplitude distortion.Receive in Sonar system corresponding, when processor processes distorted signal, the signal characteristic parameter obtained cannot meet the setting value of detecting device, signal characteristic parameter can comprise: the amplitude, frequency, signal correction amplitude etc. of signal, therefore distorted signal can cause the reduction of the Sonar system detection perform received, and causes system undetected.For traditional compensation method, be generally compensated by the transmitting voltage response of reasonable design match circuit to transducer, reduce the amplitude distortion transmitted.But still there is larger difference in the signal after actual compensation and ideal signal, reach the compensation effect of ideal signal if want, the exponent number of the match circuit of design will become very high.Transport function due to actual transducer is difficult to represent with analytical function and the element forming match circuit is not ideal element, and it is very difficult for therefore realizing required high-order match circuit, increases the design difficulty of whole emission coefficient.

Summary of the invention

The object of this invention is to provide a kind of amplitude distortion that transmits that can reduce, compensating wide band Sonar system transmits the method for amplitude.

The present invention is achieved by the following technical solutions:

Compensating wide band Sonar system transmits the method for amplitude, comprises following step,

Step one: sonar emission coefficient launches ideal linearity FM signal x ₀[n], in anechoic tank, utilizes desirable sonar receiving system to gather the distortion linear FM signal y [n] of transducer transmitting; Wherein, sonar emission coefficient comprises ideal signal source, power amplifier, broadband matching network and transducer, and described its bandwidth of ideal linearity FM signal is the bandwidth of operation of sonar emission coefficient;

Step 2: by distortion linear FM signal y [n] and ideal linearity FM signal x ₀[n] structure obtains error function e [n], finds and meets min{ Ε [e ²[n]] } estimated value of the broadband matching network of condition and the transport function of transducer according to the estimated value of the transport function of broadband matching network and transducer obtain the transport function w [n] of amplitude compensator;

Step 3: carry out after amplitude adjustment through amplitude compensator by the ideal linearity FM signal that sonar emission coefficient in step one is launched, exports the linear FM signal of adjustment;

Step 4: utilize power amplifier that the linear FM signal that amplitude compensator exports adjustment is carried out power amplification;

Step 5: the linear FM signal after power amplification is exported to transducer through broadband matching network;

Step 6: transform electrical signals is that acoustical signal is radiated in water by transducer;

Step 7: in anechoic tank, utilizes desirable sonar receiving system to gather the acoustical signal of transducer transmitting.

A kind of compensating wide band Sonar system of the present invention transmits the method for amplitude, can also comprise:

1, in step one, sonar emission coefficient launches ideal linearity FM signal x ₀[n], in anechoic tank, the process utilizing desirable sonar receiving system to gather the distortion linear FM signal y [n] that transducer is launched is:

(1) ideal linearity FM signal is carried out power amplification through power amplifier;

(2) the ideal linearity FM signal after amplification is exported to transducer through broadband matching network;

(3) transform electrical signals is that acoustical signal is radiated in water by transducer;

(4) desirable sonar receiving system utilizes collector to gather the distortion linear FM signal of transducer transmitting in water.

2, broadband matching network design process is specially:

(1) the input impedance data Z of electric impedance analyzer testing transducer is utilized _l(s);

(2) impedance data Z is utilized _ls () calculates the output impedance function Z of broadband matching network _q(s);

(3) according to Z _qs broadband matching network that () calculates realize structure and parameter.

3, the input impedance data Z of electric impedance analyzer testing transducer is utilized _ls (), calculates the output impedance function Z of broadband matching network _qs () detailed process is:

(1) the input impedance data Z of electric impedance analyzer testing transducer is utilized _l(s);

(2) set the output impedance of broadband matching network as Z _qs (), target power transmission gain is T ₀, setting unknowm coefficient A ₀, c _jand T ₀, try to achieve the error function ε of power delivery gain:

$\mathrm{\ϵ}=T(A_0,c)-T_0=\frac{(1-{\left|S_G\right|}^2)(1-{\left|S_{\mathrm{in}}(A_0,c)\right|}^2)}{{|1-S_G{S}_{\mathrm{in}}(A_0,c)|}^2}-T_0$

Wherein:

$S_G=\frac{Z_l\left(s\right)-1}{Z_l\left(s\right)+1}$

$S_{\mathrm{in}}(A_0,c)=\frac{h_q\left(s\right)}{h_q(-s)}\·\frac{Z_l\left(s\right)-Z_q(-s)}{Z_l\left(s\right)+Z_q\left(s\right)}$

h _q(s)h _q(-s)＝Ε _V{Z _q(s)}

Z _q(s)＝R _q(s)+jX _q(s)＝R _q(s)+j·Hilbert{R _q(s)}

$R_q\left(\mathrm{\ω}\right)=\frac{A_0{\mathrm{\ω}}^{2\·\mathrm{ndc}}}{B_1{\mathrm{\ω}}^{2n}+B_2{\mathrm{\ω}}^{2(n-1)}+...+B_n{\mathrm{\ω}}^2+1}=\frac{A\left({\mathrm{\ω}}^2\right)}{B\left({\mathrm{\ω}}^2\right)}$

$B\left({\mathrm{\ω}}^2\right)=\frac{1}{2}[c^2\left(\mathrm{\ω}\right)+c^2(-\mathrm{\ω})]>0$

c(ω)＝c ₁ω ⁿ+c ₂ω ^(n-1)+...+c _nω+1

S _g, S _infor normalization reflection coefficient;

Z _l(s): the input impedance impedance data of transducer;

Z _q(s): the driving point immittance function of broadband matching network;

Z _q(-s): the driving point immittance function Z of broadband matching network _qthe conjugate function of (s);

Ε _v{ Z _q(s) }: the even portion of the driving-point function of broadband matching network;

H _q(s): be Ε _v{ Z _q(s) } the Hurwitz polynomial expression that forms of the root of point submultinomial RHP and the polynomial ratio of Hurwitz that forms of the root of point submultinomial Left half-plane;

H _q(-s): be Ε _v{ Z _q(s) } the Hurwitz polynomial expression that forms of the root of point submultinomial Left half-plane and the polynomial ratio of Hurwitz that forms of the root of point submultinomial RHP;

R _q(s): the driving point immittance function Z of broadband matching network _qthe real part of (s);

X _q(s): the driving point immittance function Z of broadband matching network _qthe imaginary part of (s);

Hilbert{R _q(s) }: R _qthe Hilbert transform of (s);

R _q(ω): be R _q(s) function when s=j ω;

B _n: be the polynomial every coefficient B of even that perseverance is positive ₁, B ₂, B _n;

A ₀: unknowm coefficient;

ω: be angular frequency;

Ndc: be arithmetic number, its size determines R _q(ω ²) number of function zero-point;

C (ω): by n unknown real coefficient c _j(j=1,2 ..., n rank polynomial expression n) formed;

C (-ω): be the conjugate function of c (ω);

(3) according to Nonlinear Least-Square Algorithm, error function ε is optimized, adopts Gauss-Newton to make error function ε meet mean square value minimum, that is: meet $\underset{A_0,c}{\min }{\left|\right|\mathrm{\ϵ}\left|\right|}^2=\underset{A_0,c}{\min }{[T(A_0,c)-T_0]}^2,$ Try to achieve the numerical value A after optimization ₀' and c _j';

(4) according to the A after optimization ₀' and c _j' calculate the output impedance function Z of broadband matching network _q(s).

4, transport function w [n] detailed process obtaining amplitude compensator is:

(1) according to collection distortion linear FM signal y [n] and ideal linearity FM signal x ₀[n] structure obtains error function e [n]:

$e\left[n\right]=y\left[n\right]-\hat{d}\left[n\right]=y\left[n\right]-x_0\left[n\right]*\hat{h}\left[n\right]$

Wherein: for the estimated value of the transport function of broadband matching network and transducer, equal desirable linear FM signal x ₀the estimated value of the transport function of [n] and matching network and transducer linear convolution;

(2) searching meets min{ Ε [e ²[n]] } broadband matching network and the estimated value of transport function of transducer adopt method of steepest descent during calculating, then calculate iterative formula be:

${\hat{h}}_{N+1}\left[n\right]={\hat{h}}_N\left[n\right]+2{\mathrm{\μe}}_N\left[n\right]x_0\left[n\right]$

Wherein: for transport function estimated value the N time iteration result;

for transport function estimated value the result of the N+1 time iteration;

μ: be iteration step length, i.e. controling parameters,

E _n[n]: be the N time iteration result of error function e [n];

R _xx: be input signal x ₀the autocorrelation matrix of [n];

Trace [R _xx]: the mark representing the autocorrelation matrix of input signal;

(3) the transport function w [n] of amplitude compensator and the transport function of broadband matching network and transducer pass is conjugation negate, therefore obtains the transport function w [n] of amplitude compensator:

$w\left[n\right]=\widehat{h^{*}}[-n].$

Beneficial effect:

The present invention proposes a kind of amplitude compensation method of sonar emission coefficient, the method can effectively solve because transducer directivity and transmitting voltage response rise and fall the problem of the sonar emission coefficient signal amplitude distortion caused, the transport function of the amplitude compensator that final optimization pass obtains.The concrete effect of the amplitude compensation method of this sonar emission coefficient comprises:

Desirable sonar receiving system is the standard hydrophone and measuring amplifier that use, in the bandwidth of operation used, the amplitude-frequency response of standard hydrophone and measuring amplifier is smooth, both phase response is linear, the sample frequency of collector is higher than 20 times of collection signal highest frequency, now receiving system can not cause distortion to the signal gathered, and the signal namely collected correctly can reflect the amplitude and phase information that transmit.

It is conjugation negate that the transport function of the entirety of its transport function of the amplitude compensator of final design and the matching network estimated and transducer is closed.

During final utilization, ideal signal is first through amplitude compensator, again successively through power amplifier, broadband matching network and transducer, the signal waveform of now transducer transmitting, as Fig. 6 (a), close to ideal waveform signal as Fig. 5 (a), the amplitude scintillation transmitted after compensation is less than 0.5dB.

Above-described amplitude compensation method can also expand to dissimilar transducer, different frequency of operation and different transmitting.

Feature of the present invention is the software approach adopting amplitude compensator, compensates the amplitude output signal of sonar emission coefficient.The thought of amplitude compensator is utilize the overall transport function of linear FM signal to the broadband matching network of emission coefficient and transducer of launching to estimate, and the software amplitude compensator of structure and the conjugation negate each other of its transport function.Order transmits and first launches after amplitude compensator again, reaches the object of the amplitude fine compensation that transmits with this.Whole method implementation procedure is simple, and final amplitude compensator, by software simulating, can not increase system hardware expense, and effectively improves the signal amplitude problem of dtmf distortion DTMF of emission coefficient, is particularly suitable for Sonar system and requires the occasion that transmission signal quality is high.

Accompanying drawing explanation

Fig. 1 is that a kind of compensating wide band Sonar system that embodiment one proposes transmits the method flow diagram of amplitude;

Fig. 2 is the Sonar system launch and accept composition frame chart that embodiment one proposes;

The ideal linearity FM signal x of the transmitting that Fig. 3 (a) proposes for embodiment one ₀[n] schematic diagram;

The spectrogram of the ideal linearity FM signal of the transmitting that Fig. 3 (b) proposes for embodiment one;

Fig. 4 is the broadband matching circuit of embodiment one proposition and the amplitude-frequency response figure of transducer;

The distorted signal schematic diagram that Fig. 5 (a) launches for the transducer that embodiment one proposes;

The distorted signal spectrum figure that Fig. 5 (b) launches for the transducer that embodiment one proposes;

Signal schematic representation after the compensation that Fig. 6 (a) proposes for embodiment one;

Signal spectrum figure after the compensation that Fig. 6 (b) proposes for embodiment one;

Fig. 7 is the amplitude-frequency response figure of the amplitude compensator that embodiment one proposes;

The signal schematic representation that the amplitude compensator that Fig. 8 (a) proposes for embodiment one exports;

The signal spectrum figure that the amplitude compensator that Fig. 8 (b) proposes for embodiment one exports;

Fig. 9 is the amplitude compensator connected mode schematic diagram that embodiment proposes.

Embodiment

Below in conjunction with accompanying drawing, the present invention is described in further details.

Embodiment one: a kind of compensating wide band Sonar system of present embodiment transmits the method for amplitude, specifically prepares according to following steps:

Step one, sonar emission coefficient launch ideal linearity FM signal x ₀[n], as Fig. 3 (a) and Fig. 3 (b), in anechoic tank, utilizes desirable sonar receiving system to gather the distortion linear FM signal y [n] of transducer transmitting as Fig. 5 (a) and Fig. 5 (b); Wherein, sonar emission coefficient is made up of ideal signal source, power amplifier, broadband matching circuit and transducer, described its bandwidth of ideal linearity FM signal is the bandwidth of operation of sonar emission coefficient, as shown in Figure 2, the amplitude-frequency response of broadband matching circuit and transducer as shown in Figure 4 for concrete composition connected mode;

Step 2, by distortion linear FM signal y [n] and ideal linearity FM signal x ₀[n] structure obtains error function e [n], finds and meets min{ Ε [e ²[n]] } matching network and the estimated value of transport function of transducer according to the estimated value of the transport function of matching network and transducer obtain the transport function w [n] of amplitude compensator, as shown in Figure 7, amplitude compensator connected mode as shown in Figure 9 for the amplitude-frequency response of amplitude compensator;

Step 3, sonar emission coefficient in step one is launched ideal linearity FM signal carry out after amplitude adjustment through amplitude compensator, export the linear FM signal of adjustment as Fig. 8 (a) and Fig. 8 (b);

Step 4, the linear FM signal of adjustment utilizing power amplifier to be exported by amplitude compensator carry out power amplification;

Step 5, the linear FM signal after power amplification is exported to transducer through broadband matching circuit;

Transform electrical signals is that acoustical signal is radiated in water by step 6, transducer;

Step 7, in anechoic tank, utilize desirable sonar receiving system gather transducer launch acoustical signal; Wherein, the signal launched of transducer close to desirable broadband signal as Fig. 6 (a) and Fig. 6 (b); Namely complete a kind of compensating wide band Sonar system and transmit the method for amplitude as Fig. 1.

Embodiment two: present embodiment and embodiment one unlike: in step one, sonar emission coefficient launches ideal linearity FM signal x ₀[n], as Fig. 3 (a) and Fig. 3 (b), in anechoic tank, utilizes desirable sonar receiving system to gather distortion linear FM signal y [n] detailed process of transducer transmitting:

(1) ideal linearity FM signal is carried out power amplification through power amplifier;

(2) the ideal linearity FM signal after amplification is exported to transducer through broadband matching circuit;

(3) transform electrical signals is that acoustical signal (distortion linear FM signal) is radiated in water by transducer;

(4) desirable Sonar system utilizes collector to gather the distortion linear FM signal of transducer transmitting as Fig. 5 (a) and Fig. 5 (b) in water;

Described desirable sonar receiving system processes for using standard hydrophone and measuring amplifier docking second signal, bandwidth internal standard nautical receiving set amplitude-frequency response and measuring amplifier amplitude-frequency response that standard hydrophone and measuring amplifier are gathering acoustical signal (distortion linear FM signal) are all smooth, the response of bandwidth internal standard hydrophone phase and measuring amplifier phase response are linearly, namely can not cause distorted signals; The sample frequency of collector is higher than more than 20 times of collection signal frequency, undistorted to ensure the signal gathered.Other step and parameter identical with embodiment one.

Embodiment three: other steps of present embodiment are identical with embodiment one or two, unlike: step one middle width strip matching network design process is specially:

(1) the input impedance data Z of electric impedance analyzer testing transducer is utilized _l(s);

(2) impedance data Z is utilized _ls () calculates the output impedance function Z of matching network _q(s);

(3) according to Z _qs broadband matching network that () calculates realize structure and parameter.Other step and parameter identical with embodiment one or two.

Embodiment four: one of present embodiment and embodiment one to three are unlike the input impedance data Z that utilizes electric impedance analyzer testing transducer _ls (), utilizes impedance data Z _ls () calculates the output impedance function Z of matching network _qs () detailed process is:

(1) the input impedance data Z of electric impedance analyzer testing transducer is utilized _l(s);

(2) set the output impedance of matching network as Z _qs (), target power transmission gain is T ₀, then the error function ε of the power delivery gain constructed is as follows:

$\mathrm{\ϵ}=T(A_0,c)-T_0=\frac{(1-{\left|S_G\right|}^2)(1-{\left|S_{\mathrm{in}}(A_0,c)\right|}^2)}{{|1-S_G{S}_{\mathrm{in}}(A_0,c)|}^2}-T_0---\left(1\right)$

Wherein:

$S_G=\frac{Z_l\left(s\right)-1}{Z_l\left(s\right)+1}---\left(2\right)$

$S_{\mathrm{in}}(A_0,c)=\frac{h_q\left(s\right)}{h_q(-s)}\·\frac{Z_l\left(s\right)-Z_q(-s)}{Z_l\left(s\right)+Z_q\left(s\right)}---\left(3\right)$

h _q(s)h _q(-s)＝Ε _V{Z _q(s)} (4)

Z _q(s)＝R _q(s)+jX _q(s)＝R _q(s)+j·Hilbert{R _q(s)} (5)

$R_q\left(\mathrm{\ω}\right)=\frac{A_0{\mathrm{\ω}}^{2\·\mathrm{ndc}}}{B_1{\mathrm{\ω}}^{2n}+B_2{\mathrm{\ω}}^{2(n-1)}+...+B_n{\mathrm{\ω}}^2+1}=\frac{A\left({\mathrm{\ω}}^2\right)}{B\left({\mathrm{\ω}}^2\right)}---\left(6\right)$

$B\left({\mathrm{\ω}}^2\right)=\frac{1}{2}[c^2\left(\mathrm{\ω}\right)+c^2(-\mathrm{\ω})]>0---\left(7\right)$

c(ω)＝c ₁ω ⁿ+c ₂ω ^(n-1)+...+c _nω+1 (8)

In formula,

S _g, S _infor normalization reflection coefficient;

Z _l(s): the input impedance impedance data of transducer;

Z _q(s): the driving point immittance function of matching network;

Z _q(-s): the driving point immittance function Z of matching network _qthe conjugate function of (s);

Ε _v{ Z _q(s) }: the even portion of the driving-point function of matching network;

H _q(s): be Ε _v{ Z _q(s) } the Hurwitz polynomial expression that forms of the root of point submultinomial RHP and the polynomial ratio of Hurwitz that forms of the root of point submultinomial Left half-plane;

H _q(-s): be Ε _v{ Z _q(s) } the Hurwitz polynomial expression that forms of the root of point submultinomial Left half-plane and the polynomial ratio of Hurwitz that forms of the root of point submultinomial RHP;

R _q(s): the driving point immittance function Z of matching network _qthe real part of (s);

X _q(s): the driving point immittance function Z of matching network _qthe imaginary part of (s);

Hilbert{R _q(s) }: R _qthe Hilbert transform of (s);

R _q(ω): be R _q(s) function when s=j ω;

B _n: be the polynomial every coefficient B of even that perseverance is positive ₁, B ₂, B _n;

A ₀: unknowm coefficient;

ω: be angular frequency;

Ndc: be arithmetic number, its size determines R _q(ω ²) number of function zero-point;

C (ω): by n unknown real coefficient c _j(j=1,2 ..., n rank polynomial expression n) formed;

C (-ω): be the conjugate function of c (ω);

(3) unknown real coefficient A is set ₀, c _jand T ₀, the expression formula of error function ε is calculated according to formula (1);

(4) according to Nonlinear Least-Square Algorithm, error function ε is optimized;

Detailed process goes out one group of A for adopting Gauss-Newton method iteration ₀, c numerical value, makes error function ε meet mean square value minimum, that is: meet $\underset{A_0,c}{\min }{\left|\right|\mathrm{\ϵ}\left|\right|}^2=\underset{A_0,c}{\min }{[T(A_0,c)-T_0]}^2,$ A now ₀' and c _j' be the numerical value after optimization;

(5) A after being optimized ₀' and c _j', according to A ₀' and c _j' calculate the output impedance function Z of matching network _q(s);

5) according to the output impedance function Z of the matching network calculated _qs (), adopts continued fraction, i.e. method of successive division, Z _qs () turns to continued fraction, thus draw trapezoidal match circuit and circuit element parameter.Other step and parameter identical with one of embodiment one to three.

Embodiment five: one of present embodiment and embodiment one to four unlike: by distortion linear FM signal y [n] and ideal linearity FM signal x in step 2 ₀[n] structure obtains error function e [n], finds and meets min{ Ε [e ²[n]] } matching network and the estimated value of transport function of transducer according to the estimated value of the transport function of matching network and transducer transport function w [n] detailed process obtaining amplitude compensator is:

(1) according to collection distortion linear FM signal y [n] and ideal linearity FM signal x ₀[n] structure obtains error function e [n]:

$e\left[n\right]=y\left[n\right]-\hat{d}\left[n\right]=y\left[n\right]-x_0\left[n\right]*\hat{h}\left[n\right]$

Wherein: for the estimated value of the transport function of matching network and transducer;

for obtaining the estimated value of the output signal of transducer matching network and transducer, equal desirable linear FM signal x ₀the estimated value of the transport function of [n] and matching network and transducer linear convolution;

(2) searching meets min{ Ε [e ²[n]] } matching network and the estimated value of transport function of transducer adopt method of steepest descent during calculating, then calculate iterative formula as follows:

${\hat{h}}_{N+1}\left[n\right]={\hat{h}}_N\left[n\right]+2{\mathrm{\μe}}_N\left[n\right]x_0\left[n\right]$

Wherein: for transport function estimated value the N time iteration result;

for transport function estimated value the result of the N+1 time iteration;

μ: be iteration step length;

E _n[n]: be the N time iteration result of error function e [n];

μ is as unique controling parameters, and its typical value is 1/10th magnitudes of the mark of input signal autocorrelation matrix, is specially:

$\mathrm{\μ}=\frac{1}{10\mathrm{trace}\left[R_{\mathrm{xx}}\right]}$

R _xx: be input signal x ₀the autocorrelation matrix of [n];

Trace [R _xx]: the mark representing the autocorrelation matrix of input signal;

(3) the transport function w [n] of amplitude compensator and the transport function of matching network and transducer pass is conjugation negate, therefore obtains the transport function w [n] of amplitude compensator:

$w\left[n\right]=\widehat{h^{*}}[-n]$

Other step and parameter identical with one of embodiment one to four.

In anechoic tank, desirable sonar receiving system is utilized to gather the acoustical signal of transducer transmitting; Wherein, the signal launched of transducer close to desirable broadband signal as Fig. 6 (a) and Fig. 6 (b).According to signal waveform in Fig. 6 (a), the amplitude of whole signal is smooth, and accurate Calculation is that 0.1dB rises and falls.Do not have balanced signal as shown in Fig. 5 (a), the amplitude scintillation of whole signal is comparatively large, and accurate Calculation is 6dB.Therefore illustrate that amplitude compensator can play good Amplitude Compensation effect to transmitting.

Claims (5)

1. compensating wide band Sonar system transmits a method for amplitude, it is characterized in that: comprise following step,

Step one: sonar emission coefficient launches ideal linearity FM signal x ₀[n], in anechoic tank, utilizes desirable sonar receiving system to gather the distortion linear FM signal y [n] of transducer transmitting; Wherein, sonar emission coefficient comprises ideal signal source, power amplifier, broadband matching network and transducer, and described its bandwidth of ideal linearity FM signal is the bandwidth of operation of sonar emission coefficient;

Step 2: by distortion linear FM signal y [n] and ideal linearity FM signal x ₀[n] structure obtains error function e [n], finds and meets min{ Ε [e ²[n]] } estimated value of the broadband matching network of condition and the transport function of transducer according to the estimated value of the transport function of broadband matching network and transducer obtain the transport function w [n] of amplitude compensator;

Step 3: carry out after amplitude adjustment through amplitude compensator by the ideal linearity FM signal that sonar emission coefficient in step one is launched, exports the linear FM signal of adjustment;

Step 4: utilize power amplifier that the linear FM signal that amplitude compensator exports adjustment is carried out power amplification;

Step 5: the linear FM signal after power amplification is exported to transducer through broadband matching network;

Step 6: transform electrical signals is that acoustical signal is radiated in water by transducer;

Step 7: in anechoic tank, utilizes desirable sonar receiving system to gather the acoustical signal of transducer transmitting.

2. a kind of compensating wide band Sonar system according to claim 1 transmits the method for amplitude, it is characterized in that: in described step one, sonar emission coefficient launches ideal linearity FM signal x ₀[n], in anechoic tank, the process utilizing desirable sonar receiving system to gather the distortion linear FM signal y [n] that transducer is launched is:

(1) ideal linearity FM signal is carried out power amplification through power amplifier;

(2) the ideal linearity FM signal after amplification is exported to transducer through broadband matching network;

(3) transform electrical signals is that acoustical signal is radiated in water by transducer;

(4) desirable sonar receiving system utilizes collector to gather the distortion linear FM signal of transducer transmitting in water.

3. a kind of compensating wide band Sonar system according to claim 1 transmits the method for amplitude, it is characterized in that: described broadband matching network design process is specially:

(1) the input impedance data Z of electric impedance analyzer testing transducer is utilized _l(s);

(2) impedance data Z is utilized _ls () calculates the output impedance function Z of broadband matching network _q(s);

(3) according to Z _qs broadband matching network that () calculates realize structure and parameter.

4. a kind of compensating wide band Sonar system according to claim 3 transmits the method for amplitude, it is characterized in that: the described input impedance data Z utilizing electric impedance analyzer testing transducer _ls (), calculates the output impedance function Z of broadband matching network _qs () detailed process is:

(1) the input impedance data Z of electric impedance analyzer testing transducer is utilized _l(s);

(2) set the output impedance of broadband matching network as Z _qs (), target power transmission gain is T ₀, setting unknowm coefficient A ₀, c _jand T ₀, try to achieve the error function ε of power delivery gain:

$\mathrm{\ϵ}=T(A_0,c)-T_0=\frac{(1-{\left|S_G\right|}^2)(1-{\left|S_{\mathrm{in}}(A_0,c)\right|}^2)}{{|1-S_G{S}_{\mathrm{in}}(A_0,c)|}^2}-T_0$

Wherein:

$S_G=\frac{Z_l\left(s\right)-1}{Z_l\left(s\right)+1}$

$S_{\mathrm{in}}(A_0,c)=\frac{h_q\left(s\right)}{h_q(-s)}\·\frac{Z_l\left(s\right)-Z_q(-s)}{Z_l\left(s\right)+Z_q\left(s\right)}$

h _q(s)h _q(-s)＝Ε _V{Z _q(s)}

Z _q(s)＝R _q(s)+jX _q(s)＝R _q(s)+j·Hilbert{R _q(s)}

$R_q\left(\mathrm{\ω}\right)=\frac{A_0{\mathrm{\ω}}^{2\·\mathrm{ndc}}}{B_1{\mathrm{\ω}}^{2n}+B_2{\mathrm{\ω}}^{2(n-1)}+...+B_n{\mathrm{\ω}}^2+1}=\frac{A\left({\mathrm{\ω}}^2\right)}{B\left({\mathrm{\ω}}^2\right)}$

$B\left({\mathrm{\ω}}^2\right)=\frac{1}{2}[c^2\left(\mathrm{\ω}\right)+c^2(-\mathrm{\ω})]>0$

c(ω)＝c ₁ω ⁿ+c ₂ω ^(n-1)+…+c _nω+1

S _g, S _infor normalization reflection coefficient;

Z _l(s): the input impedance impedance data of transducer;

Z _q(s): the driving point immittance function of broadband matching network;

Z _q(-s): the driving point immittance function Z of broadband matching network _qthe conjugate function of (s);

Ε _v{ Z _q(s) }: the even portion of the driving-point function of broadband matching network;

H _q(s): be Ε _v{ Z _q(s) } the Hurwitz polynomial expression that forms of the root of point submultinomial RHP and the polynomial ratio of Hurwitz that forms of the root of point submultinomial Left half-plane;

H _q(-s): be Ε _v{ Z _q(s) } the Hurwitz polynomial expression that forms of the root of point submultinomial Left half-plane and the polynomial ratio of Hurwitz that forms of the root of point submultinomial RHP;

R _q(s): the driving point immittance function Z of broadband matching network _qthe real part of (s);

X _q(s): the driving point immittance function Z of broadband matching network _qthe imaginary part of (s);

Hilbert{R _q(s) }: R _qthe Hilbert transform of (s);

R _q(ω): be R _q(s) function when s=j ω;

B _n: be the polynomial every coefficient B of even that perseverance is positive ₁, B ₂, B _n;

A ₀: unknowm coefficient;

ω: be angular frequency;

Ndc: be arithmetic number, its size determines R _q(ω ²) number of function zero-point;

C (ω): by n unknown real coefficient c _j(j=1,2 ..., n rank polynomial expression n) formed;

C (-ω): be the conjugate function of c (ω);

(3) according to Nonlinear Least-Square Algorithm, error function ε is optimized, adopts Gauss-Newton to make error function ε meet mean square value minimum, that is: meet try to achieve the numerical value A ' after optimization ₀with c ' _j;

(4) according to the A ' after optimization ₀with c ' _jcalculate the output impedance function Z of broadband matching network _q(s).

5. a kind of compensating wide band Sonar system according to claim 1 transmits the method for amplitude, it is characterized in that: described transport function w [n] detailed process obtaining amplitude compensator is:

(1) according to collection distortion linear FM signal y [n] and ideal linearity FM signal x ₀[n] structure obtains error function e [n]:

$e\left[n\right]=y\left[n\right]-\hat{d}\left[n\right]=y\left[n\right]-x_0\left[n\right]*\hat{h}\left[n\right]$

Wherein: for the estimated value of the transport function of broadband matching network and transducer, equal desirable linear FM signal x ₀the estimated value of the transport function of [n] and matching network and transducer linear convolution;

(2) searching meets min{ Ε [e ²[n]] } broadband matching network and the estimated value of transport function of transducer adopt method of steepest descent during calculating, then calculate iterative formula be:

${\hat{h}}_{N+1}\left[n\right]={\hat{h}}_N\left[n\right]+2{\mathrm{\μe}}_N\left[n\right]x_0\left[n\right]$

Wherein: : be transport function estimated value the N time iteration result;

: be transport function estimated value the result of the N+1 time iteration;

μ: be iteration step length, i.e. controling parameters,

E _n[n]: be the N time iteration result of error function e [n];

R _xx: be input signal x ₀the autocorrelation matrix of [n];

Trace [R _xx]: the mark representing the autocorrelation matrix of input signal;

(3) the transport function w [n] of amplitude compensator and the transport function of broadband matching network and transducer pass is conjugation negate, therefore obtains the transport function w [n] of amplitude compensator:

$w\left[n\right]=\widehat{h^{*}}[-n].$