CN105929376A - Smart jamming noise signal design method based on velocity pull-off - Google Patents

Abstract

The invention provides a smart jamming noise signal design method based on velocity pull-off and relates to the smart jamming noise signal design method. The smart jamming noise signal design method based on the velocity pull-off is put forward to solve the problem that false target track is easy to be cancelled by radar anti-interference when uncorrelated, so that the effect of suppression jamming cannot be achieved, and the effect of anti-jamming measures, such as echo sidelobe cancellation, is not good enough. The method is realized through the following steps: 1) calculating time delay tau; 2) calculating Doppler frequency shift fd obtained after an electromagnetic signal is reflected back to a radar antenna through secondary scattering of a target; 3) calculating the amplitude value At of a target echo signal at the time t after the electromagnetic signal is reflected back to the radar antenna through secondary scattering of the target; 4) calculating the target echo signal sr(t); and 5) increasing offset of the Doppler frequency shift fd. The method is applied to the smart jamming noise signal design field.

Description

Smart munition noise signal method for designing based on speed tracting

Technical field

The present invention relates to smart munition noise signal method for designing, particularly to smart munition noise signal based on speed tracting Method for designing.

Background technology

Assuming that radar emission signal is linear FM signal s (t), its expression formula is:

$s\left(t\right)=A\exp \[j2\mathrm{\π}(f_{0}t+\frac{{\mathrm{\μt}}^2}{2})\]---\left(1\right)$

Wherein, f₀For carrier frequency, μ is chirp rate.Assuming that target is point target, scattering resonance state is σ, target range For R, then the receptance function of target is:

H (t)=σ δ (t-τ_R) (2)

Wherein, τ_R=R/ (2c), c are the light velocity, then target echo is:

$s_r\left(t\right)=s\left(t\right)\⊗h\left(t\right)---\left(3\right)$

If the pulse compression coefficient of signal processor is s^*(-t), after matched filtering, after obtaining pulse pressure, target echo is expressed Formula is as follows:

$s_{pc}\left(t\right)=s^{*}(-t)\⊗s_r\left(t\right)=s^{*}(-t)\⊗s\left(t\right)\⊗h\left(t\right)---\left(4\right)$

The frequency spectrum making h (t) is H (f), and the frequency spectrum of s (t) is S (f), then after matched filtering, the frequency spectrum of result is:

S_pc(f)=H (f) | S (f) |² (5)

Its time-domain expression can be write:

$s_{pc}\left(t\right)=F^{-1}\left(S_{pc}\right(f\left)\right)=F^{-1}\left({\left|S\left(f\right)\right|}^2\right)\⊗h\left(t\right)---\left(6\right)$

Wherein F^-1(S_pc(f)) it is the point spread function of linear FM signal.See if frequency spectrum S (f) of linear FM signal is approximated Rectangular function, then point spread function is Sinc function, it can be seen that target echo pulse compression output result is decided by Target response function.

Derived from above, arbitrary function synteny FM signal phase convolution, its pulse compression output signal be this function and The convolution of point spread function, also can obtain process of pulse-compression gain.

(1) Pulse convolution jamming

The multi-form used according to video signal can produce the interference waveform of multi-form.Assume h (t) be k amplitude not The train of pulse formed with the shock pulse that time delay is different, then h (t) can be expressed as:

$h\left(t\right)=\underset{i=1}{\overset{k}{\mathrm{\Σ}}}{U}_i\mathrm{\δ}(t-t_i)---\left(7\right)$

Wherein U_iFor each pulse amplitude, t_iFor each impulse time delay.The linear FM signal of the radar emission of intercepting and capturing is divided by jammer Not being displaced to the position of k shock pulse, convolution results is equivalent to k time delay different, the radar signal that amplitude is different It is overlapped.Each linear FM signal have identical time-frequency characteristic with radar echo signal, therefore can obtain identical Pulse compression gain.The mechanism that this situation produces Range Profile with the target that multi-scatter is constituted is identical, i.e. at real goal Create the point target of multiple vacation afterwards.

Pulse convolution jamming can function well as the effect of cheating interference as from the foregoing, but decoy quantity is very little, it is impossible to Play the effect of pressing type interference.

Electronic countermeasure and anti-countermeasure techniques are the important component parts of modern high technology war, through whole war all the time, Outcome of a war is played key effect.Radar system is the kernel object that electronic countermeasure is anti-with opposition, therefore, carries out radar System interference technical research is one of subject study direction of extremely paying attention to outside Present Domestic.

In recent years, along with the gradually ripe of digital RF storage (DRFM) technology and extensively use, have concurrently cheating interference and The smart noise jamming of the feature of noise jamming progressively becomes noticeable novel interference.Video is used in the interference of this type Noise carries out the modulation in time domain to the radar emission signal intercepted and captured, produce in time domain and frequency domain with real target echo weight Folding and the signal waveform of coverage goal echo, signal energy utilization rate is high, but to interference protection measures such as echo sidelobe cancellations Less effective.

Summary of the invention

The invention aims to solve easily to be offseted by Radar cross-section redaction when decoy flight path is uncorrelated, it is impossible to play pressing type The effect of interference and the problem of the less effective of the interference protection measures such as echo sidelobe cancellation is proposed based on speed tracting Smart munition noise signal method for designing.

Above-mentioned goal of the invention is achieved through the following technical solutions:

After step one, the electromagnetic signal of calculating radar emission are irradiated to target, the rescattering through target returns to radar sky Time delay τ of line；

After step 2, the electromagnetic signal of calculating radar emission are irradiated to target, the rescattering through target returns to radar sky The Doppler frequency shift f of line_d；

After step 3, the electromagnetic signal of calculating radar emission are irradiated to target, the rescattering through target returns to radar sky The range value A of line t target echo signal_t；

Step 4, assume that radar emission signal is s_t(t), then target echo signal s_rT the expression formula of () is:

$\begin{array}{c}{s}_r\left(t\right)=A_t{s}_t(t-\mathrm{\τ})e^{j2{\mathrm{\πf}}_{d}t}\\ ={\[\frac{{\mathrm{\λ}}^2}{{\left(4\mathrm{\π}\right)}^3{R}_t^4}\]}^{1/2}G\·\mathrm{\γ}\·s_t(t-\mathrm{\τ})e^{j2{\mathrm{\πf}}_{d}t}\end{array}---\left(13\right)$

In formula, e is natural logrithm；J is intermediate variable；G is the reception gain of radar antenna, and γ is connecing of radar antenna Produce effects rate；R_tFor the radial distance between t target and radar；λ is the operation wavelength of radar；

Step 5, speed tracting；According to radar echo signal s_rT (), speed tracting interference signal compares target echo letter Number add Doppler frequency shift f_dSide-play amount, it may be assumed that

s_r(t)=A_texp[j′(ω_c+ω_d+Δω)(t-2R_t/c)] (14)

In formula, A_tRange value for t target echo；ω_cFor radar emission signal frequency；ω_dFor target relative to radar footpath To the produced Doppler frequency of motion；Δ ω is the keeper signal frequency departure relative to real motion target, is interference letter Number tow speed in Doppler frequency corresponding to radar observation radially projecting；R_tRadial direction between t target and radar away from From；C is the light velocity, i.e. propagation velocity of electromagnetic wave；J ' () is imaginary symbols；

Speed gate pull-off jamming signal Doppler frequency shift f corresponding for Δ ω in formula (14)_d' change procedure be expressed as:

In formula, v_fSpeed is towed in Algorithm for Doppler Frequency Rate-of-Change corresponding to radar observation radially projecting, unit for interference signal Hz/s, v_f(t-t₁) tow speed in Doppler frequency corresponding to radar observation radially projecting for interference signal, wherein v_f≤2a/λ；A is the peak acceleration of radar lock on；t₁The capture time of circuit is followed the tracks of, typically for radar speed For 0.5s～2s；T_jFor smart munition noise signal simulation time based on speed tracting；t₂Tie for speed tracting Disturbance and deceit The bundle moment.

Invention effect

The present invention is from radar smart noise jamming signal based on Convolution Modulation, and combining target echo-signal flight path is correlated with skill Art, devises a kind of interference waveform speed tracting deception and Convolution Modulation dexterity noise combined, has deception concurrently to strengthen With the smart noise jamming effect of noise jamming, and the interference effect etc. of this signal form is carried out simulating, verifying.

Object of the present invention is to provide smart munition noise signal ripple design under a kind of true complex environment, its form structure Simply it is easily achieved and has the strongest actual application potential quality, enhancing the smart noise jamming having deception and noise jamming concurrently Effect.It is an object of the invention to provide new dexterous noise signal ripple method for designing, improve the antagonism in actual electronic countermeasure Ability.For the dexterous noise Anti-Jamming Technique such as sidelobe cancellation and SLB technique, make an uproar analyzing Convolution Modulation smart munition On the basis of the working mechanism of acoustical signal, introduce speed tracting deception, it is proposed that smart munition noise signal based on speed tracting Waveform Design；

As an innovation of the present invention, by speed Tracking ripple door is towed out from the Doppler frequency of real goal, make Obtain radar to lose target Doppler frequency and cannot be carried out correctly following the tracks of, it may be assumed that

s_r(t)=A_texp[j(ω_c+ω_d+Δω)(t-2R_t/c)]

In formula, Δ ω is the keeper signal frequency departure relative to real goal.Speed gate pull-off jamming signal Doppler frequency The change procedure of rate is expressed as:

In formula, f_dFor the Doppler frequency of true echo-signal, v_f(Hz/s) towing speed for interference signal, its value is little In the peak acceleration of radar lock on, i.e. v_f≤2a/λ。

It is an object of the invention to improve destruction by new more practical signal wave design or hinder the radar frequency to target The ability of rate detection, improves survival ability.Implementation method is:

Effectively to disturb the radar acquisition and tracking ability to target, be necessary for making full use of the work characteristics of radar equipment, from energy Radar tracking system is implemented interference by amount, distance, speed and angle many aspects.Therefore the effective noise signal built is necessary There is following two feature:

1) there is high density decoy, the echo of real goal can be covered；

2) angel echoes in noise signal does not require nothing more than and has identical intrapulse modulation characteristic with real goal echo, and And the flight path of angel echoes must be correlated with, to resist the interference protection measures such as sidelobe cancellation.

Based on above feature, in the present invention, the flight path of angel echoes is relevant reenters movement difference equations realization by target aircraft Velocity correlation.

The present invention compares situation when being originally not added with speed tracting, has had good lifting, because of difference in terms of deception adds compacting In the case of response situation different, but in general, capability improving scope is at 30%-60% such as Fig. 3 and Fig. 4.

The present invention is directed to the reality of smart munition noise anti-sidelobe cancellation less effective, combining target echo flight path correlation technique, Devise a kind of novel interference signal form speed tracting deception and Convolution Modulation dexterity noise combined, have concurrently to strengthen Deception and the smart noise jamming effect of noise jamming.It is an advantage of the current invention that this Waveform Design destroys radar range finding system The stability of system tracking loop, enhances the interference deception of signal and pressing result so that conventional echo sidelobe cancellation processes, The interference protection measures such as echo peak signal MTD, MTD-CFAR lost efficacy.The present invention is shown by simulation analysis: based on speed The smart noise jamming signal form that degree tows has reached design effect, has engineer applied and is worth.

Main advantages of the present invention are embodied in: can realize destroying the stability of radar ranging system tracking loop, enhance dry Disturb deception and the pressing result of signal so that conventional echo sidelobe cancellation process, echo peak signal MTD, The interference protection measures such as MTD-CFAR lost efficacy, and improve practicality.Such as Fig. 5 (a), Fig. 5 (b), Fig. 6 and Fig. 7.

The present invention uses smart noise jamming realization method to consider, and video noise signal is considered as a lot of amplitude is random impact Train of pulse, therefore makees video noise signal by shock pulse falsification, and with linear FM signal convolution, then the interference produced is just Be equivalent to the linear FM signal sum that a lot of amplitude random delay is intensive.

Setting video noise is n (t), and the interference echo that video noise produces with radar signal convolution is:

$J_r\left(t\right)=s\left(t\right)\⊗n\left(t\right)---\left(8\right)$

The result of matched filtering is:

$J_{pc}\left(t\right)=F^{-1}\left(J_{pc}\right(f\left)\right)=F^{-1}\left({\left|S\left(f\right)\right|}^2\right)\⊗n\left(t\right)---\left(9\right)$

From time domain, the interference waveform that so modulation is formed just is decided by phase convolution therewith through the result of pulse compression Video noise.And disturb signal can obtain part or all of gain after pulse compression, produce intensive decoy, with Time take into account deception and pressing type interference effect.Analyzing from frequency domain, convolution is equivalent to frequency domain and is multiplied, and linear frequency modulation is believed Number being considered as passband is [f₀-B/2,f₀-B/2] band filter, therefore produce Convolution Modulation interference time, do not having Just can disturb and just can fully enter receiver with the frequency domain of coverage goal echo, significantly carry in the case of carrying out frequency alignment High interference utilization rate.

Accompanying drawing explanation

Fig. 1 (a) is Hybrid-modulated Signal (13 Barker code+linear frequency modulations) the radar emission signal waveforms that embodiment proposes；

Fig. 1 (b) is signal spectrum radar emission signal waveforms in the code that embodiment proposes；

Fig. 2 is the preferable radar echo pulse compression result that embodiment proposes；

Fig. 3 is the echo-signal (time domain) of 3 decoys that embodiment proposes；

Fig. 4 is the echo-signal (frequency domain) of 3 decoys that embodiment proposes；

Fig. 5 (a) is 3 target echo sidelobe cancellation result real part schematic diagrams that embodiment proposes；

Fig. 5 (b) is 3 target echo sidelobe cancellation result imaginary part schematic diagrams that embodiment proposes；

Fig. 6 is 3 target echo peak signal MTD results that embodiment proposes；

Fig. 7 is 3 target echo MTD-CFAR results (using CFAR result) that embodiment proposes；

Fig. 8 is that based on speed tracting the dexterous noise signal that embodiment proposes produces block diagram.

Detailed description of the invention

Detailed description of the invention one: the smart munition noise signal method for designing based on speed tracting of present embodiment, specifically Prepare according to following steps:

After the electromagnetic signal that step one, interference echo guinea pig are launched is irradiated to target, the rescattering through target returns To radar antenna；Now, the echo-signal of target is compared with the transmitting signal of radar, in time, frequency and amplitude three There is significantly change in individual aspect；After the electromagnetic signal of calculating radar emission is irradiated to target, the rescattering through target is returned Return to time delay τ of radar antenna；The size of this time delay reflects the target radial distance relative to radar；

After step 2, the electromagnetic signal of calculating radar emission are irradiated to target, the rescattering through target returns to radar sky The Doppler frequency shift f of line_d；

After step 3, the electromagnetic signal of calculating radar emission are irradiated to target, the rescattering through target returns to radar sky The range value A of line t target echo signal_t；

Step 4, based on step one, two and three, it is assumed that radar emission signal is s_t(t), then target echo signal s_r(t) Expression formula is:

$\begin{array}{c}{s}_r\left(t\right)=A_t{s}_t(t-\mathrm{\τ})e^{j2{\mathrm{\πf}}_{d}t}\\ ={\[\frac{{\mathrm{\λ}}^2}{{\left(4\mathrm{\π}\right)}^3{R}_t^4}\]}^{1/2}G\·\mathrm{\γ}\·s_t(t-\mathrm{\τ})e^{j2{\mathrm{\πf}}_{d}t}\end{array}---\left(13\right)$

In formula, e is natural logrithm；J is intermediate variable；G is the reception gain of radar antenna, and γ is connecing of radar antenna Produce effects rate；R_tFor the radial distance between t target and radar；λ is the operation wavelength of radar；

Step 5, speed tracting；The purpose of speed tracting interference is exactly to destroy or hinder the radar frequency sonding to target, By speed Tracking ripple door is towed out from the Doppler frequency of real goal so that radar loses target Doppler frequency and nothing Method is correctly followed the tracks of；According to radar echo signal s_rT (), speed tracting interference signal is compared target echo signal and is added Doppler frequency shift f_dSide-play amount, it may be assumed that

s_r(t)=A_texp[j′(ω_c+ω_d+Δω)(t-2R_t/c)] (14)

In formula, A_tRange value for t target echo；ω_cFor radar emission signal frequency；ω_dFor target relative to radar footpath To the produced Doppler frequency of motion；Δ ω is the keeper signal frequency departure relative to real motion target, is interference letter Number tow speed in Doppler frequency corresponding to radar observation radially projecting；R_tRadial direction between t target and radar away from From；C is the light velocity, i.e. propagation velocity of electromagnetic wave；J ' () is imaginary symbols；

Speed gate pull-off jamming signal Doppler frequency shift f corresponding for Δ ω in formula (14)_d' change procedure be expressed as:

In formula, v_fSpeed is towed in Algorithm for Doppler Frequency Rate-of-Change corresponding to radar observation radially projecting, unit for interference signal Hz/s, v_f(t-t₁) tow speed in Doppler frequency corresponding to radar observation radially projecting for interference signal, wherein v_f≤2a/λ；A is the peak acceleration of radar lock on；t₁The capture time of circuit is followed the tracks of, typically for radar speed For 0.5s～2s；t₂-t₁For speed tracting Disturbance and deceit time, t₂-t₁Should be slightly bigger than radar speed and follow the tracks of the capture of circuit Time and agc circuit sum recovery time, generally 0.5s～2s, period pull-off jamming signal makes radar speed tracking loop Progressively disengage the true Doppler frequency of the target originally followed the tracks of；T_j-t₂For interference signal quit work the phase, generally 3s with On；T_jFor smart munition noise signal simulation time based on speed tracting；t₂For speed tracting Disturbance and deceit finish time.

Present embodiment effect:

Present embodiment is from radar smart noise jamming signal based on Convolution Modulation, combining target echo-signal flight path phase Pass technology, devises a kind of interference waveform speed tracting deception and Convolution Modulation dexterity noise combined, has concurrently to strengthen Deception and the smart noise jamming effect of noise jamming, and the interference effect etc. of this signal form has been carried out emulation test Card.

The purpose of present embodiment there are provided smart munition noise signal ripple design under a kind of true complex environment, its form Simple in construction is easily achieved and has the strongest actual application potential quality, enhances the dexterous noise having deception and noise jamming concurrently Interference effect.The purpose of present embodiment is to provide new dexterous noise signal ripple method for designing, improves actual electronic countermeasure In antagonism.For the dexterous noise Anti-Jamming Technique such as sidelobe cancellation and SLB technique, analyzing Convolution Modulation spirit On the basis of the working mechanism of skilful interfering noise signal, introduce speed tracting deception, it is proposed that smart munition based on speed tracting Noise signal waveforms designs；

As an innovation of present embodiment, by speed Tracking ripple door is towed out from the Doppler frequency of real goal, Radar is made to lose target Doppler frequency and cannot be carried out correctly following the tracks of, it may be assumed that

s_r(t)=A_texp[j(ω_c+ω_d+Δω)(t-2R_t/c)]

In formula, Δ ω is the keeper signal frequency departure relative to real goal.Speed gate pull-off jamming signal Doppler frequency The change procedure of rate is expressed as:

In formula, f_dFor the Doppler frequency of true echo-signal, v_f(Hz/s) towing speed for interference signal, its value is little In the peak acceleration of radar lock on, i.e. v_f≤2a/λ。

The purpose of present embodiment is to be improved destruction by new more practical signal wave design or hindered radar to target The ability of frequency sonding, improve survival ability.Implementation method is:

Effectively to disturb the radar acquisition and tracking ability to target, be necessary for making full use of the work characteristics of radar equipment, from energy Radar tracking system is implemented interference by amount, distance, speed and angle many aspects.Therefore the effective noise signal built is necessary There is following two feature:

1) there is high density decoy, the echo of real goal can be covered；

2) angel echoes in noise signal does not require nothing more than and has identical intrapulse modulation characteristic with real goal echo, and And the flight path of angel echoes must be correlated with, to resist the interference protection measures such as sidelobe cancellation.

Based on above feature, in present embodiment, the flight path of angel echoes is relevant reenters movement difference equations by target aircraft Realize velocity correlation.

Present embodiment compares situation when being originally not added with speed tracting, has had good lifting in terms of deception adds compacting, because of Under different situations, response situation is different, but in general, capability improving scope is at 30%-60% such as Fig. 3 and Fig. 4.

Present embodiment is for the reality of smart munition noise anti-sidelobe cancellation less effective, and combining target echo flight path is correlated with skill Art, devises a kind of novel interference signal form speed tracting deception and Convolution Modulation dexterity noise combined, to strengthen Have the smart noise jamming effect of deception and noise jamming concurrently.Advantage of this embodiment is that this Waveform Design destroys thunder Reach the stability of range-measurement system tracking loop, enhance deception and the pressing result of interference signal so that conventional echo secondary lobe Offset the interference protection measures such as process, echo peak signal MTD, MTD-CFAR to lose efficacy.Present embodiment is by emulation point Analysis shows: smart noise jamming signal form based on speed tracting has reached design effect, has engineer applied and is worth.

The major advantage of present embodiment is embodied in: can realize destroying the stability of radar ranging system tracking loop, strengthen The deception of interference signal and pressing result so that conventional echo sidelobe cancellation process, echo peak signal MTD, The interference protection measures such as MTD-CFAR lost efficacy, and improve practicality.Such as Fig. 5 (a), Fig. 5 (b), Fig. 6 and Fig. 7.

It is random that present embodiment uses smart noise jamming realization method to be considered as a lot of amplitude in view of video noise signal Shock pulse string, therefore makees video noise signal by shock pulse falsification, and with linear FM signal convolution, then produce is dry Disturb and be equivalent to the linear FM signal sum that a lot of amplitude random delay is intensive.

Setting video noise is n (t), and the interference echo that video noise produces with radar signal convolution is:

$J_r\left(t\right)=s\left(t\right)\⊗n\left(t\right)---\left(8\right)$

The result of matched filtering is:

$J_{pc}\left(t\right)=F^{-1}\left(J_{pc}\right(f\left)\right)=F^{-1}\left({\left|S\left(f\right)\right|}^2\right)\⊗n\left(t\right)---\left(9\right)$

From time domain, the interference waveform that so modulation is formed just is decided by phase convolution therewith through the result of pulse compression Video noise.And disturb signal can obtain part or all of gain after pulse compression, produce intensive decoy, with Time take into account deception and pressing type interference effect.Analyzing from frequency domain, convolution is equivalent to frequency domain and is multiplied, and linear frequency modulation is believed Number being considered as passband is [f₀-B/2,f₀-B/2] band filter, therefore produce Convolution Modulation interference time, do not having Just can disturb and just can fully enter receiver with the frequency domain of coverage goal echo, significantly carry in the case of carrying out frequency alignment High interference utilization rate.

Detailed description of the invention two: present embodiment is unlike detailed description of the invention one: time delay τ described in step one Particularly as follows:

τ=2R_t/c (11)

In formula, τ is that target echo signal is relative to the time delay launching signal.Other step and parameter and detailed description of the invention one Identical.

Detailed description of the invention three: present embodiment is unlike detailed description of the invention one or two: through looking over so as to check described in step 2 Target rescattering returns to the Doppler frequency shift f of radar antenna_dParticularly as follows:

When there is relative radial motion between target and radar, the frequency of target echo signal will change, and i.e. occur many General Le effect；Due to the impact of Doppler effect, there is Doppler frequency shift in the frequency of target echo signal compared with tranmitting frequency f_dExpression formula is:

$f_d=2v_{R_t}/\mathrm{\λ}---\left(12\right)$

In formula,It is target range radar R_tTime target relative to the radial velocity of radar.Other step and parameter and tool Body embodiment one or two is identical.

Detailed description of the invention four: present embodiment is unlike one of detailed description of the invention one to three: the width described in step 3 Angle value A_tParticularly as follows:

$A_t={\[\frac{{\mathrm{\λ}}^2}{{\left(4\mathrm{\π}\right)}^3{R}_t^4}\]}^{1/2}G\·\mathrm{\γ}$

Owing to the target scattering process to electromagnetic wave, only part energy are saved the situation along the incident direction reflection of radar electromagnetic wave Line.The degree of amplitude fading is heavily dependent on the Radar Cross Section (RCS) of target, it addition, additionally depend on The impact of various factors in the various losses of system and communication process.Other step and parameter and detailed description of the invention one to three One of identical.

Detailed description of the invention five: present embodiment is unlike one of detailed description of the invention one to four: t described in step 5₁For 0.5s～2s.Other step and parameter are identical with one of detailed description of the invention one to four.

Employing following example checking beneficial effects of the present invention:

Embodiment one:

The present embodiment smart munition based on speed tracting noise signal method for designing, specifically prepares according to following steps:

Generate ballistic trajectory

Range in view of target reentry stage is less, and the flight time is shorter, it is therefore assumed that target is transported for plane in reentry stage motion Dynamic, setting up reentry stage movement difference equations under velocity coordinate system is:

$\left\{\begin{array}{c}\frac{dV}{dt}=-\frac{X}{m}-gsin\mathrm{\Θ}\\ \frac{d\mathrm{\Θ}}{dt}=(\frac{V}{r}-\frac{g}{V})\cos \mathrm{\Θ}\\ \frac{dr}{dt}=V\cos \mathrm{\Θ}\\ \frac{{\mathrm{d\β}}_e}{dt}=\frac{V}{r}\cos \mathrm{\Θ}\end{array}\right.---\left(10\right)$

Wherein, V is the flight speed (m/s) of target；X is the air drag (N) suffered by target；M is aimed quality (kg)；G is gravity acceleration magnitude (m/s²)；R is target the earth's core radius vector size (m)；Θ is that speed is to local horizontal line Inclination angle (rad)；β_eFor the angle of range (rad) during target flight.

For above-mentioned analysis, the present embodiment is first according to supposing that target obtains three in the position in space and stressing conditions, emulation Bar meets the flight path of Target Motion Character；Secondly according to position, war technical specification and the ripple of the radar chaff target detected in advance Shape feature produces radar target signal；Then multi-false targets echo-signal is carried out speed tracting, finally uses Rayleigh to make an uproar Acoustical signal carries out Convolution Modulation and produces smart noise jamming.Signal produces block diagram and sees that Fig. 8, radar set with jammer simulation parameter Put and be shown in Table 1.

Table 1 radar and jammer running parameter

Radar and jammer running parameter according to supposing carry out smart noise jamming signal simulation based on speed tracting, knot Fruit sees accompanying drawing, and wherein Fig. 1 (a)～Fig. 2 is ideally radar emission signal waveform and target echo pulse pressure result； Fig. 3～Fig. 4 be the time domain of 3 target echoes based on speed tracting and frequency domain figure, Fig. 5 (a)～Fig. 7 fixing for using Clutter cancellation technology and MTD technology carry out object detection results to smart noise jamming signal based on speed tracting.

From above simulation analysis result it can be seen that use smart noise jamming signal based on speed tracting having deception concurrently While compacting radar chaff performance, the speed tracting deception of introducing destroys stablizing of radar ranging system tracking loop Property so that interference protection measure conventional in radar electronic warfare lost efficacy, and had reached intended design effect；

Novel based on speed tracting the smart munition noise signal waveforms method for designing proposed according to the present invention, for radar electric Antagonism proposes new thinking.

The present invention also can have other various embodiments, in the case of without departing substantially from present invention spirit and essence thereof, and art technology Personnel are when making various corresponding change and deformation according to the present invention, but these change accordingly and deformation all should belong to this Bright appended scope of the claims.

Claims (5)

1. smart munition noise signal method for designing based on speed tracting, it is characterised in that the method specifically according to Lower step is carried out:

After step one, the electromagnetic signal of calculating radar emission are irradiated to target, the rescattering through target returns to radar sky Time delay τ of line；

After step 2, the electromagnetic signal of calculating radar emission are irradiated to target, the rescattering through target returns to radar sky The Doppler frequency shift f of line_d；

After step 3, the electromagnetic signal of calculating radar emission are irradiated to target, the rescattering through target returns to radar sky The range value A of line t target echo signal_t；

Step 4, assume that radar emission signal is s_t(t), then target echo signal s_rT the expression formula of () is:

$\begin{array}{c}{s}_r\left(t\right)=A_t{s}_t(t-\mathrm{\τ})e^{j2{\mathrm{\πf}}_{d}t}\\ ={\[\frac{{\mathrm{\λ}}^2}{{\left(4\mathrm{\π}\right)}^3{R}_t^4}\]}^{1/2}G\·\mathrm{\γ}\·s_t(t-\mathrm{\τ})e^{j2{\mathrm{\πf}}_{d}t}\end{array}---\left(13\right)$

In formula, e is natural logrithm；J is intermediate variable；G is the reception gain of radar antenna, and γ is the reception of radar antenna Efficiency；R_tFor the radial distance between t target and radar；λ is the operation wavelength of radar；

Step 5, speed tracting；According to radar echo signal s_rT (), speed tracting interference signal compares target echo signal Add Doppler frequency shift f_dSide-play amount, it may be assumed that

s_r(t)=A_texp[j′(ω_c+ω_d+△ω)(t-2R_t/c)] (14)

In formula, A_tRange value for t target echo；ω_cFor radar emission signal frequency；ω_dFor target relative to radar footpath To the produced Doppler frequency of motion；△ ω is the keeper signal frequency departure relative to real motion target, is interference signal Tow speed in Doppler frequency corresponding to radar observation radially projecting；R_tIt it is the radial distance between t target and radar； C is the light velocity, i.e. propagation velocity of electromagnetic wave；J ' () is imaginary symbols；

Speed gate pull-off jamming signal Doppler frequency shift f corresponding for △ ω in formula (14)_d' change procedure be expressed as:

In formula, v_fSpeed is towed in Algorithm for Doppler Frequency Rate-of-Change corresponding to radar observation radially projecting, unit for interference signal Hz/s, v_f(t-t₁) tow speed in Doppler frequency corresponding to radar observation radially projecting for interference signal, wherein v_f≤2a/λ；A is the peak acceleration of radar lock on；t₁The capture time of circuit is followed the tracks of for radar speed；T_jFor base Smart munition noise signal simulation time in speed tracting；t₂For speed tracting Disturbance and deceit finish time.

Smart munition noise signal method for designing based on speed tracting the most according to claim 1, it is characterised in that: step Time delay τ described in rapid one particularly as follows:

τ=2R_t/c (11)

In formula, τ is that target echo signal is relative to the time delay launching signal.

Smart munition noise signal method for designing based on speed tracting the most according to claim 2, it is characterised in that: Rescattering through target described in step 2 returns to the Doppler frequency shift f of radar antenna_dParticularly as follows:

When there is relative radial motion between target and radar, there is Doppler effect；The frequency of target echo signal with send out Radio frequency rate is compared and be there is Doppler frequency shift f_dExpression formula is:

$f_d=2v_{R_t}/\mathrm{\λ}---\left(12\right)$

In formula,It is target range radar R_tTime target relative to the radial velocity of radar.

Smart munition noise signal method for designing based on speed tracting the most according to claim 3, it is characterised in that: step Range value A described in rapid three_tParticularly as follows:

$A_t={\[\frac{{\mathrm{\λ}}^2}{{\left(4\mathrm{\π}\right)}^3{R}_t^4}\]}^{1/2}G\·\mathrm{\γ}.$

Smart munition noise signal method for designing based on speed tracting the most according to claim 4, it is characterised in that: T described in step 5₁For 0.5s～2s.