CN104678367A - Velocity deception interference resisting method for airborne pulse Doppler radar - Google Patents

Abstract

The invention belongs to the anti-interference technique for design of an airborne pulse Doppler radar system, and relates to a radar single-target velocity deception interference resisting method. The radar single-target velocity deception interference resisting method comprises the following steps of 1, enabling a radar to detect and track a target, obtaining the frequency of a single-target point tracking center, dividing by 1,000, converting into kHz, and recording as f0; 2, in the tracking process, when one target point is tracked, setting the tracking as the normal single-target point tracking, and directly finishing; 3, utilizing a weighting coefficient method to calculate the frequency weight of a plurality of target points; (1) solving the weight; (2) solving the weighting frequency and fsum=fmu*bmu+fjam*bjam; (3) solving the weighting coefficient and csum=bmu+bjam; (4) solving the weighting result: as shown in the attached figure; 4 sending the weighting result to a radar tracking center. The method has the advantages that the identifying of the deception interference is not needed, the interference information and the target information are inputted together to process, and the velocity deception interference can be resisted; the velocity deception interference can be effectively resisted, and the target is reliably and accurately tracked; the calculation amount is less, the operation speed is high, and the portability is high.

Description

The anti-velocity gate deception interference method of a kind of Airborne Pulse Doppler Radar

Technical field

The invention belongs to the Anti-Jamming Technique in Airborne Pulse Doppler Radar system, relate to the anti-velocity gate deception interference method of a kind of radar single goal.

Background technology

Velocity gate deception interference is generally Doppler frequency interference, its ultimate principle is: according to the radar signal received, jammer forwards several undesired signals different from target echo Doppler frequency fd simultaneously, make the speed tracing circuit of radar multiple Doppler frequency be detected simultaneously, or be difficult to fd real goal being detected, affect normal detecting and tracking.Effective velocity gate deception undesired signal has two obvious features compared with real goal: 1. Doppler frequency is different from real goal; 2. signal power is better than or equals real goal.

When the carrier of radar to jammer is in Continuous Tracking state, just can hinder and damage its speed tracing with speed tracting, and then reach the object disturbing radar normally to follow the tracks of.Concrete grammar is, after jammer detects the other side's radar signal, amplified by the radar pulse received, and the appropriate Doppler shift (corresponding radial velocity) of extra increase is launched again.Attached Doppler shift increases by specific rule or reduces (simulation accelerated or decelerating flight), and under towing echo strength and being greater than the condition of target echo, the speed gate of radar will be dragged away.One typically tows method can be divided into following components:

The section of catching: object is the speed gate making jammer detect the other side's radar:

Speed tracting section: effect tows radar speed ripple door by undesired signal;

Maintaining segment: effect makes the speed gate of radar stably follow the tracks of undesired signal;

Stop segment: stop launching undesired signal, effect is that the speed tracing Bo Mennei undesired signal of radar is disappeared.

Undesired signal because speed tracing ripple door is disturbed impact, departs from target echo after disappearing, so without any signal in speed tracing door, cause radar to exit tracking mode, re-start search.Once radar is again after target acquisition echo, jammer restarts new to tow the cycle.Radar is so just made to be disturbed impact and can not tenacious tracking to be kept.

The method of anti-velocity gate deception interference, phase in " radar science and technology " April 02 in 2004 " Kohonen network be used for Radar Anti velocity gate deception disturb in feature extraction ", the articles such as phase the 22nd volume in volume the 5th phase " under speed tracting moving object detection " and " electronic information countermeasure techniques " May the 3rd in 2007 " systems engineering and electronic technology " calendar year 2001 the 23rd "-identification way disturbed of velocity gate deception of adjusting the distance " have research, it is also proposed some concrete grammars, but these methods stay in simulation analysis of computer more, and be based upon and judge it is target or interference in advance, and then carry out on the basis that processes, be not applied in actual radar system.

Summary of the invention

The object of the invention is: the method proposing the anti-velocity gate deception interference of a kind of Airborne Pulse Doppler Radar.The method can make radar effectively resist velocity gate deception interference when monotrack (STT), carries out reliably and accurately following the tracks of to target, and meet that calculated amount is little, fast operation, portable high requirement.

Technical scheme of the present invention: method involved in the present invention is that the interconnected filtered method of probability data develops, it realizes being consider to fall into all candidate's echoes in detection zone, do not differentiate target or cheating interference, according to the frequency change of these echoes, give the weighting coefficient that different echo is different, make target weight large, cheating interference weight is little, make inspection center be partial to target, thus resist velocity gate deception interference.

The anti-velocity gate deception interference method of a kind of Airborne Pulse Doppler Radar, comprises the following steps:

Step 1: by detections of radar, tracking target, obtains monocular punctuate and follows the tracks of centre frequency, convert kHz to, be designated as f divided by 1000 ₀;

Step 2: in tracing process, if be 1 impact point, be normal monotrack, directly terminate;

If there is multiple impact point, then enroll the frequency information of multiple impact point, by the frequency of each impact point divided by 1000, convert kHz to, be designated as f _mu, f _jam;

Step 3: utilize weighting factor method, calculates the frequency weight of above-mentioned multiple impact point;

(1) power is asked

a _mu＝abs(f _mu-f ₀)，

a _jam＝abs(f _jam-f ₀)，

$b_{\mathrm{mu}}=e^{-c*a_{\mathrm{mu}}},$

$b_{\mathrm{jam}}=e^{-c*a_{\mathrm{jam}}},$

A _mufor target frequency f _mucentre frequency f is followed the tracks of with monocular punctuate ₀the absolute value of difference;

A _jamfor interfering frequency f _mucentre frequency f is followed the tracks of with monocular punctuate ₀the absolute value of difference;

(2) ask weighted frequency and

f _sum＝f _mu×b _mu+f _jam×b _jam，

(3) ask weighting coefficient and

c _sum＝b _mu+b _jam，

(4) weighted results is asked:

$f_g=\frac{f_{\mathrm{sum}}}{c_{\mathrm{sum}}};$

C is constant, g _mu, g _jamfor the frequency change rate of target and interference.

t*g _mu＜f _g-f _mu＜t*gj _am

Namely $t*g_{\mathrm{mu}}<\frac{f_{\mathrm{jam}}{e}^{-c*a_{\mathrm{jam}}}+f_{\mathrm{mu}}{e}^{-c*a_{\mathrm{mu}}}}{e^{-c*a_{\mathrm{jam}}}+e^{-c*a_{\mathrm{mu}}}}-f_{\mathrm{mu}}<t*g_{\mathrm{jam}}$

${t*g}_{\mathrm{mu}}<\frac{f_{\mathrm{jam}}{e}^{{-c*a}_{\mathrm{jam}}}-f_{\mathrm{mu}}{e}^{{-c*a}_{\mathrm{jam}}}}{e^{{-c*a}_{\mathrm{jam}}}+e^{{-c*a}_{\mathrm{mu}}}}<{t*g}_{\mathrm{jam}}$

${t*g}_{\mathrm{mu}}<\frac{f_{\mathrm{jam}}-f_{\mathrm{mu}}}{1+e^{-c*(a_{\mathrm{mu}}-a_{\mathrm{jam}})}}<{t*g}_{\mathrm{jam}}$

$\frac{-1}{a_{\mathrm{mu}}-a_{\mathrm{jam}}}\ln (\frac{f_{\mathrm{jam}}-f_{\mathrm{mu}}}{{t*g}_{\mathrm{mu}}}-1)<c<\frac{-1}{a_{\mathrm{mu}}-a_{\mathrm{jam}}}\ln (\frac{f_{\mathrm{jam}}-f_{\mathrm{mu}}}{{t*g}_{\mathrm{jam}}}-1)$

Namely $\frac{-1}{a_{\mathrm{mu}}-a_{\mathrm{jam}}}\ln (\frac{f_z}{{t*g}_{\mathrm{mu}}}-1)<c<\frac{-1}{a_{\mathrm{mu}}-a_{\mathrm{jam}}}\ln (\frac{f_z}{{t*g}_{\mathrm{jam}}}-1)$

Wherein f _z=f _jam-f _mu

$\frac{-1}{\left|g_{\mathrm{mu}}\right|-\left|g_{\mathrm{jam}}\right|}\ln (\frac{f_z}{{t*g}_{\mathrm{mu}}}-1)<c<\frac{-1}{\left|g_{\mathrm{mu}}\right|-\left|g_{\mathrm{jam}}\right|}\ln (\frac{f_a}{{t*g}_{\mathrm{jam}}}-1)$

T is the frame period,

F _zduring for detecting target, the minimum distinguishable frequency interval of interference and target;

Step 4: give Radar Tracking Center weighted results.

The present invention has following several advantages: the maximum bright spot of this method, without the need to differentiating cheating interference, interference, target information being inputted together, processes, and just can resist velocity gate deception interference; Effectively can resist velocity gate deception interference, carry out reliably and accurately following the tracks of to target; Calculated amount is little, fast operation, portable high.

Accompanying drawing explanation

Fig. 1 is process flow diagram of the present invention.

Embodiment

Below in conjunction with Figure of description, the invention will be further described:

The anti-velocity gate deception interference method of a kind of Airborne Pulse Doppler Radar, comprises the following steps:

Step 1: by detections of radar, tracking target, obtains monocular punctuate and follows the tracks of center, convert kHz to, be designated as f ₀;

Step 2: in tracing process, if be 1 impact point, be normal monotrack, directly terminate;

If there is multiple impact point, then enroll the frequency information of multiple impact point, by frequency/1000 of each impact point, convert kHz to, be designated as f _mu, f _jam;

Step 3: utilize weighting factor method, calculates the frequency weight of above-mentioned multiple impact point;

(1) power is asked

a _mu＝abs(f _mu-f ₀)，

a _jam＝abs(f _jam-f ₀)；

$b_{\mathrm{mu}}=e^{-c*a_{\mathrm{mu}}},$

$b_{\mathrm{jam}}=e^{-c*a_{\mathrm{jam}}};$

(2) ask weighted frequency and

f _sum＝f _mu×b _mu+f _jam×b _jam，

(3) ask weighting coefficient and

c _sum＝b _mu+b _jam，

(4) weighted results is asked

$f_g=\frac{f_{\mathrm{sum}}}{c_{\mathrm{sum}}};$

C is constant, g _mu, g _jamfor the frequency change rate of target and interference

g _mu＜f _g-f _mu＜g _jam

Namely $t*g_{\mathrm{mu}}<\frac{f_{\mathrm{jam}}{e}^{-c*a_{\mathrm{jam}}}+f_{\mathrm{mu}}{e}^{-c*a_{\mathrm{mu}}}}{e^{-c*a_{\mathrm{jam}}}+e^{-c*a_{\mathrm{mu}}}}-f_{\mathrm{mu}}<t*g_{\mathrm{jam}}$

${t*g}_{\mathrm{mu}}<\frac{f_{\mathrm{jam}}{e}^{{-c*a}_{\mathrm{jam}}}-f_{\mathrm{mu}}{e}^{{-c*a}_{\mathrm{jam}}}}{e^{{-c*a}_{\mathrm{jam}}}+e^{{-c*a}_{\mathrm{mu}}}}<{t*g}_{\mathrm{jam}}$

${t*g}_{\mathrm{mu}}<\frac{f_{\mathrm{jam}}-f_{\mathrm{mu}}}{1+e^{-c*(a_{\mathrm{mu}}-a_{\mathrm{jam}})}}<{t*g}_{\mathrm{jam}}$

$\frac{-1}{a_{\mathrm{mu}}-a_{\mathrm{jam}}}\ln (\frac{f_{\mathrm{jam}}-f_{\mathrm{mu}}}{{t*g}_{\mathrm{mu}}}-1)<c<\frac{-1}{a_{\mathrm{mu}}-a_{\mathrm{jam}}}\ln (\frac{f_{\mathrm{jam}}-f_{\mathrm{mu}}}{{t*g}_{\mathrm{jam}}}-1)$

Namely $\frac{-1}{a_{\mathrm{mu}}-a_{\mathrm{jam}}}\ln (\frac{f_z}{{t*g}_{\mathrm{mu}}}-1)<c<\frac{-1}{a_{\mathrm{mu}}-a_{\mathrm{jam}}}\ln (\frac{f_z}{{t*g}_{\mathrm{jam}}}-1)$

Wherein f _z=f _jam-f _mu

$\frac{-1}{\left|g_{\mathrm{mu}}\right|-\left|g_{\mathrm{jam}}\right|}\ln (\frac{f_z}{{t*g}_{\mathrm{mu}}}-1)<c<\frac{-1}{\left|g_{\mathrm{mu}}\right|-\left|g_{\mathrm{jam}}\right|}\ln (\frac{f_a}{{t*g}_{\mathrm{jam}}}-1)$

T is the frame period,

F _zduring for detecting target, the minimum distinguishable frequency interval of interference and target;

Step 4: give Radar Tracking Center weighted results.

Embodiment: for certain type radar, the frequency change rate g of target _mufor 1.5KHz/s ~ 2KHz/s, the frequency change rate g of interference _jamfor 3KHz/s ~ 4KHz/s, minimum distinguishable frequency interval f _zfor 1kHz, t are that 0.05s, c are taken as 2.

Utilize weighting factor method, under monotrack environment, if the echo fallen in detection zone is more than one, in these candidate's echoes, one is only had to be from target, all the other are all produced by false-alarm or " clutter ", undesired signal is used as false-alarm or clutter, adopts the weighting coefficient with frequency dependence, make the weight of target large, the weight of interference is little, make the weight of target much larger than the weight of interference, process the signal sent and echo signal frequency close, trend towards echo signal.Focus on the selection of weighting coefficient, choosing method is shown in step 3.Adopt weighting coefficient method, finally trend towards tracking target, reach the effect of anti-velocity gate deception.

This method has passed through the long-term Flight of certain model radar, effectively can resist velocity gate deception interference, carry out reliably and accurately following the tracks of to target.

Claims (1)

1. the anti-velocity gate deception interference method of Airborne Pulse Doppler Radar, is characterized in that comprising the following steps:

Step 1: by detections of radar, tracking target, obtains monocular punctuate and follows the tracks of centre frequency, convert kHz to, be designated as f divided by 1000 ₀;

Step 2: in tracing process, if be 1 impact point, be normal monotrack, directly terminate;

If there is multiple impact point, then enroll the frequency information of multiple impact point, by the frequency of each impact point divided by 1000, convert kHz to, be designated as f _mu, f _jam;

Step 3: utilize weighting factor method, calculates the frequency weight of above-mentioned multiple impact point;

(1) power is asked

a _mu＝abs(f _mu-f ₀)，

a _jam＝abs(f _jam-f ₀)，

$b_{\mathrm{mu}}=e^{-c*a_{\mathrm{mu}}},$

$b_{\mathrm{jam}}=e^{-c*a_{\mathrm{jam}}},$

A _mufor target frequency f _mucentre frequency f is followed the tracks of with monocular punctuate ₀the absolute value of difference;

A _jamfor interfering frequency f _mucentre frequency f is followed the tracks of with monocular punctuate ₀the absolute value of difference;

(2) ask weighted frequency and

f _sum＝f _mu×b _mu+f _jam×b _jam，

(3) ask weighting coefficient and

c _sum＝b _mu+b _jam，

(4) weighted results is asked:

$f_g=\frac{f_{\mathrm{sum}}}{c_{\mathrm{sum}}};$

C is constant, g _mu, g _jamfor the frequency change rate of target and interference.

t*g _mu＜f _g-f _mu＜t*g _jam

Namely $t*g_{\mathrm{mu}}<\frac{f_{\mathrm{jam}}{e}^{-c*a_{\mathrm{jam}}}+f_{\mathrm{mu}}{e}^{-c*a_{\mathrm{mu}}}}{e^{-c*a_{\mathrm{jam}}}+e^{-c*a_{\mathrm{mu}}}}-f_{\mathrm{mu}}<t*g_{\mathrm{jam}}$

${t*g}_{\mathrm{mu}}<\frac{f_{\mathrm{jam}}{e}^{{-c*a}_{\mathrm{jam}}}-f_{\mathrm{mu}}{e}^{{-c*a}_{\mathrm{jam}}}}{e^{{-c*a}_{\mathrm{jam}}}+e^{{-c*a}_{\mathrm{mu}}}}<{t*g}_{\mathrm{jam}}$

${t*g}_{\mathrm{mu}}<\frac{f_{\mathrm{jam}}-f_{\mathrm{mu}}}{1+e^{-c*(a_{\mathrm{mu}}-a_{\mathrm{jam}})}}<{t*g}_{\mathrm{jam}}$

$\frac{-1}{a_{\mathrm{mu}}-a_{\mathrm{jam}}}\ln (\frac{f_{\mathrm{jam}}-f_{\mathrm{mu}}}{{t*g}_{\mathrm{mu}}}-1)<c<\frac{-1}{a_{\mathrm{mu}}-a_{\mathrm{jam}}}\ln (\frac{f_{\mathrm{jam}}-f_{\mathrm{mu}}}{{t*g}_{\mathrm{jam}}}-1)$

Namely $\frac{-1}{a_{\mathrm{mu}}-a_{\mathrm{jam}}}\ln (\frac{f_z}{{t*g}_{\mathrm{mu}}}-1)<c<\frac{-1}{a_{\mathrm{mu}}-a_{\mathrm{jam}}}\ln (\frac{f_z}{{t*g}_{\mathrm{jam}}}-1)$

Wherein f _z=f _jam-f _mu

$\frac{-1}{\left|g_{\mathrm{mu}}\right|-\left|g_{\mathrm{jam}}\right|}\ln (\frac{f_z}{{t*g}_{\mathrm{mu}}}-1)<c<\frac{-1}{\left|g_{\mathrm{mu}}\right|-\left|g_{\mathrm{jam}}\right|}\ln (\frac{f_a}{{t*g}_{\mathrm{jam}}}-1)$

T is the frame period,

F _zduring for detecting target, the minimum distinguishable frequency interval of interference and target;

Step 4: give Radar Tracking Center weighted results.