CN105182310A - Statistic and calibrating method of angular deviation of target near field under maneuvering intersection - Google Patents

Abstract

The invention relates to a statistic and calibrating method of angular deviation of a target near field under maneuvering intersection. On the basis of a relative comparison method, statistics is carried out on minimum distance amount results of maneuvering intersection of a radar and a target and maneuvering intersection of a radar and a metal ball; and a distance fluctuation characteristic of angular deviation of the target near field on the near field condition is calibrated by using a statistic root mean square. According to the invention, the change of the near-filed angular deviation with the distance is considered, so that the prevision of the angular deviation model is improved; and with calibration, the angular deviation fluctuation of the target is equivalent to random noises, thereby substantially simplifying the angular deviation model in a near field state.

Description

A kind of probability demarcation method of Target near field angle scintillations under motor-driven intersection

Technical field

The present invention relates to electromagnetic characteristic of scattering emulation technology, particularly relate to the probability demarcation method of Target near field angle scintillations under a kind of motor-driven intersection.

Background technology

Angle scintillations, also referred to as angular displacement, the deviation namely between radar target apparent Angle Position and target's center's Angle Position.When radar receives the coherent electromagnetic wave of diverse location radiation, the distortion of electromagnetic phase wavefront will cause angle scintillations.For target scattering situation, if target scale and wavelength can be compared and be had two or more equivalent scattering centers, be about to cause obvious angle scintillations.This deviation normally leaves with radar apparent center that the lateral separation of target geometric center represents, i.e. linear glint error.Linear glint error is the key property of Extended target.

The angle scintillations phenomenon that the wavefront distortion of radar target signal phase causes is the main source of error affecting tracking radar angle measurement accuracy.At present, situation (such as [1] blackish red one-tenth of target angle flicker under most researchs main discussion far-field approximation condition, Huang Peikang, Wang Chao, discuss the angle scintillations of Extended target again, systems engineering and electronic technology, 2007, Vol.29, No.4, 499 ~ 504, [2] Wang Chao, blackish red one-tenth, Feng Xiaobin, Huang Peikang, the computing method of complex target angle scintillations are discussed from the viewpoint of polarization, systems engineering and electronic technology, 2008, Vol.30, No.7, 1195 ~ 1199), think that target linear glint error is the amount irrelevant with distance, and have ignored near-field effect ([3] model red flag of angle scintillations, Wang Sheng, Zhu Yilong, Fu Qiang, phase gradient method calculates the analytic expression of near field angle scintillations, electronic letters, vol, 2009, Vol.37, No.5).But under the Near-field observation such as spacecrafts rendezvous, terminal guidance condition, target linear glint error is with acute variation such as observed range, observation visual angles, the near-field effect of angle scintillations be can not ignore, and directly will affect radar and target relative movement track, and the near field angle scintillations of target also will change thereupon.Therefore, in the motor-driven intersection process of radar and target, Target near field angle scintillations and motor-driven intersection track are interactional, the near-field target angle scintillations studying a certain position does not possess practical value isolatedly, requires that in the motor-driven intersection overall process of synthetic study, near-field target angle scintillations is on the impact of radar tracking performance.

Summary of the invention

The invention provides the probability demarcation method of Target near field angle scintillations under a kind of motor-driven intersection, count the change of near field angle scintillations with distance, improve the precision of angle scintillations model, by demarcating, the fluctuating of the angle scintillations of target being equivalent to a kind of random noise, significantly simplifying the angle scintillations model in the situation of near field.

In order to achieve the above object, the invention provides the probability demarcation method of Target near field angle scintillations under a kind of motor-driven intersection, comprise following steps:

Carry out the motor-driven rendezvous simulation of radar and target, obtain the minimum relative distance set { d of the motor-driven rendezvous simulation of radar and target _ti, i=1 ..., N, N are emulation intersection number of times;

Carry out the motor-driven rendezvous simulation of radar and Metal Ball calibration body, obtain the minimum relative distance set { d of the motor-driven rendezvous simulation of radar and Metal Ball calibration body _qi, i=1 ..., N, N are emulation intersection number of times;

Calculate the root mean square σ of the minimum relative distance set of the motor-driven rendezvous simulation of radar and target respectively _t, radar and Metal Ball calibration body the root mean square σ of minimum relative distance set of motor-driven rendezvous simulation _q, and the root mean square σ of random meausrement error of radar system itself _e;

${\mathrm{\σ}}_T=\sqrt{\frac{\underset{i=1}{\overset{N}{\Σ}}{(d_{Ti}-u_T)}^2}{N-1}}---\left(1\right)$

Wherein, u _tfor set { d _tiaverage, N is emulation intersection number of times;

${\mathrm{\σ}}_Q=\sqrt{\frac{\underset{i=1}{\overset{N}{\Σ}}{(d_{Qi}-u_Q)}^2}{N-1}}---\left(2\right)$

Wherein, u _qfor set { d _qiaverage, N is emulation intersection number of times;

${\mathrm{\σ}}_e=\sqrt{\frac{\underset{i=0}{\overset{M}{\Σ}}{\left(e_0\right(t_j)-u_e)}^2}{M}}---\left(3\right)$

Wherein, e ₀(t _j) be random meausrement error, u _efor the average of the random meausrement error of radar system itself, M is the number of discrete time point;

Calculate the relative Calibration result e of Target near field angle scintillations in motor-driven intersection _t;

$e_T=\frac{{\mathrm{\σ}}_T}{{\mathrm{\σ}}_Q}{\mathrm{\σ}}_e---\left(4\right).$

Carry out the motor-driven rendezvous simulation of radar and target, the minimum relative distance set obtaining the motor-driven rendezvous simulation of radar and target comprises following steps:

Step S101, calculating line of sight angle, obtain line of sight angle rate of change e'(t in time);

$e^{\′}\left(t_j\right)=\mathrm{\ω}\left(t_j\right)+\frac{e_T(t_j+\mathrm{\Δ}t)+e_0(t_j+\mathrm{\Δ}t)-e_T\left(t_j\right)-e_0\left(t_j\right)}{\mathrm{\Δ}t}---\left(5\right)$

Wherein, t _j=j Δ t is the time discrete value in the motor-driven rendezvous simulation of radar and target, and Δ t is time discrete interval, j=0,1 ..., M, M are the number of discrete time point; ω (t _j) be t _jmoment, target's center was relative to the angular velocity of radar; e _t(t _j) be Target near field angle scintillations, unit is degree; e ₀(t _j) be the random meausrement error of radar system itself, unit is degree, e ₀(t _j) a certain size random number simulation can be utilized to obtain;

Step S102, according to line of sight angle rate of change e'(t in time) calculate the transverse acceleration a (t of radar motion _j);

Step S103, calculating subsequent time t _jduring+Δ t, the speed of related movement vector Δ v of radar and target and relative position Δ s;

Δv＝a(t _j)Δt；

wherein, being average velocity, is moment t _jwith subsequent time t _j+ Δ t speed and 1/2;

Step S104, relative distance according to distance between two points formulae discovery radar and target, circulation emulation, detects radar and target relative distance changes in time, when this relative distance is by when reducing to increase change, namely complete once motor-driven rendezvous simulation, obtain the minimum relative distance of radar and target;

Step S105, impact due to radar random meausrement error, to identical radar and target reference position and speed, the minimum relative distance of the motor-driven rendezvous simulation of different number of times is different, carries out repeatedly motor-driven rendezvous simulation, obtains the minimum relative distance set { d of the motor-driven rendezvous simulation of radar and target _ti, i=1 ..., N, N are emulation intersection number of times.

Adopt and obtain the radar method same with the minimum relative distance set of the motor-driven rendezvous simulation of target, carry out the motor-driven rendezvous simulation of radar and Metal Ball calibration body, obtain the minimum relative distance set of the motor-driven rendezvous simulation of radar and Metal Ball calibration body.

The present invention adopts relatively method, the motor-driven intersection minor increment amount result of radar and target, radar and Metal Ball is added up respectively, the distance fluctuation characteristic of Target near field angle scintillations in the situation of recycling statistics root mean square demarcation near field, the present invention has the following advantages: 1, the present invention has counted the change of Target near field angle scintillations with distance, improves the precision of angle scintillations model; 2, the fluctuating of the angle scintillations of target is equivalent to a kind of random noise by demarcating by the present invention, significantly simplifies the angle scintillations model in the situation of near field, reaches the real-time calculation requirement in radar system hardware-in-the-loop simulation.

Accompanying drawing explanation

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

Fig. 2 is the random meausrement error of radar system in motor-driven intersection process.

Fig. 3 is that the motor-driven rendezvous simulation of radar number of times different from target obtains minimum relative distance and distributes.

Fig. 4 is that the motor-driven rendezvous simulation of radar number of times different from Metal Ball obtains minimum relative distance and distributes.

Embodiment

Following according to Fig. 1 ~ Fig. 4, illustrate preferred embodiment of the present invention.

As shown in Figure 1, the invention provides the probability demarcation method of Target near field angle scintillations under a kind of motor-driven intersection, comprise following steps:

Step S1, carry out the motor-driven rendezvous simulation of radar and target, obtain the minimum relative distance set { d of the motor-driven rendezvous simulation of radar and target _ti, i=1 ..., N, N are emulation intersection number of times;

Step S2, carry out the motor-driven rendezvous simulation of radar and Metal Ball calibration body, obtain the minimum relative distance set { d of the motor-driven rendezvous simulation of radar and Metal Ball calibration body _qi, i=1 ..., N, N are emulation intersection number of times;

The root mean square σ of step S3, the minimum relative distance set of the motor-driven rendezvous simulation of calculating radar and target respectively _t, radar and Metal Ball calibration body the root mean square σ of minimum relative distance set of motor-driven rendezvous simulation _q, and the root mean square σ of random meausrement error of radar system itself _e;

${\mathrm{\σ}}_T=\sqrt{\frac{\underset{i=1}{\overset{N}{\Σ}}{(d_{Ti}-u_T)}^2}{N-1}}---\left(1\right)$

Wherein, u _tfor set { d _tiaverage, N is emulation intersection number of times;

${\mathrm{\σ}}_Q=\sqrt{\frac{\underset{i=1}{\overset{N}{\Σ}}{(d_{Qi}-u_Q)}^2}{N-1}}---\left(2\right)$

Wherein, u _qfor set { d _qiaverage, N is emulation intersection number of times;

${\mathrm{\σ}}_e=\sqrt{\frac{\underset{i=0}{\overset{M}{\Σ}}{\left(e_0\right(t_j)-u_e)}^2}{M}}---\left(3\right)$

Wherein, e ₀(t _j) be random meausrement error, u _efor the average of the random meausrement error of radar system itself, M is the number of discrete time point;

Step S4, calculate the relative Calibration result e of Target near field angle scintillations in motor-driven intersection _t;

$e_T=\frac{{\mathrm{\σ}}_T}{{\mathrm{\σ}}_Q}{\mathrm{\σ}}_e---\left(4\right).$

In described step S1, carry out the motor-driven rendezvous simulation of radar and target, the minimum relative distance set obtaining the motor-driven rendezvous simulation of radar and target comprises following steps:

Step S101, according to the radar in certain moment and target relative position and speed of related movement vector, adopt the calculating targets such as all-wave numerical method, high frequency Asymptotical Method under radar illumination wave excitation, return the scattered field at radar place, the phase place of this scattered field is utilized to change, adopt phase gradient method to calculate and obtain target scattering direction of wave travel, i.e. line of sight angle;

Line of sight angle is rate of change e'(t in time) be:

$e^{\′}\left(t_j\right)=\mathrm{\ω}\left(t_j\right)+\frac{e_T(t_j+\mathrm{\Δ}t)+e_0(t_j+\mathrm{\Δ}t)-e_T\left(t_j\right)-e_0\left(t_j\right)}{\mathrm{\Δ}t}---\left(5\right)$

Wherein, t _j=j Δ t is the time discrete value in the motor-driven rendezvous simulation of radar and target, and Δ t is time discrete interval, j=0,1 ..., M, M are the number of discrete time point; ω (t _j) be t _jmoment, target's center was relative to the angular velocity of radar; e _t(t _j) be Target near field angle scintillations, unit is degree; e ₀(t _j) be the random meausrement error of radar system itself, unit is degree, e ₀(t _j) a certain size random number simulation can be utilized to obtain;

Step S102, according to line of sight angle rate of change e'(t in time) calculate the transverse acceleration a (t of radar motion _j);

In the present embodiment, adoption rate daoyin technique (but being not limited to the method) calculates transverse acceleration a (t _j):

a(t _j)＝kR(t _j)e'(t _j)(6)

Wherein, k is scale-up factor, R (t _j) be radar and target relative distance;

Step S103, calculating subsequent time t _jduring+Δ t, the speed of related movement vector Δ v of radar and target and relative position Δ s;

Δv＝a(t _j)Δt；

wherein, being average velocity, is moment t _jwith subsequent time t _j+ Δ t speed and 1/2;

Step S104, relative distance according to distance between two points formulae discovery radar and target, circulation emulation, detects radar and target relative distance changes in time, when this relative distance is by when reducing to increase change, namely complete once motor-driven rendezvous simulation, obtain the minimum relative distance of radar and target;

Step S105, impact due to radar random meausrement error, to identical radar and target reference position and speed, the minimum relative distance of the motor-driven rendezvous simulation of different number of times is different, carries out repeatedly motor-driven rendezvous simulation, obtains the minimum relative distance set { d of the motor-driven rendezvous simulation of radar and target _ti, i=1 ..., N, N are emulation intersection number of times.

In described step S2, adopt the method identical with step S1, carry out the motor-driven rendezvous simulation of radar and Metal Ball calibration body, obtain the minimum relative distance set { d of the motor-driven rendezvous simulation of radar and Metal Ball calibration body _qi.

Embodiment

A probability demarcation method for Target near field angle scintillations under motor-driven intersection, the method comprises following steps:

Step 1, supposition radar are (-2000m relative to the reference position of target, 0,5m), speed of related movement Δ v is 1300m/s, the time discrete interval of delta t of motor-driven rendezvous simulation is 0.005 second, in motor-driven rendezvous simulation, the number M of discrete time point is 301 points, wherein the random meausrement error e of radar system own ₀(t _j) variation range is-0.05 ° ~ 0.05 °, it scatters to meet and is uniformly distributed, and as shown in Figure 2, simulation times is 800 times, and minimum relative distance distribution is as shown in Figure 3.

Step 2, Metal Ball to diameter 0.4m, carry out motor-driven rendezvous simulation equally, simulation times is 800 times, and minor increment distribution as shown in Figure 4.

Step 3, the root mean square utilizing the radar of formula (1) computer sim-ulation and the minimum relative distance set of target are 2.1m, the root mean square utilizing the radar of formula (2) computer sim-ulation and the minimum relative distance set of the motor-driven intersection of Metal Ball is 1.6m, and the root mean square utilizing formula (3) to calculate the random meausrement error of radar system own is 0.028 °.

The calibration result that step 4, the near field angle scintillations utilizing formula (4) to calculate target in motor-driven intersection rise and fall is 0.037 °.

In the real-time simulation of radar system and target maneuver intersection, Target near field angle scintillations can be equivalent to the equally distributed random meausrement error of one in radar system, the random meausrement error root mean square of equivalence is taken as the calibration result of the near field angle scintillations fluctuating of above-mentioned target, thus significantly simplifies the near field angle scintillations computation model of target.

Although content of the present invention has done detailed introduction by above preferred embodiment, will be appreciated that above-mentioned description should not be considered to limitation of the present invention.After those skilled in the art have read foregoing, for multiple amendment of the present invention and substitute will be all apparent.Therefore, protection scope of the present invention should be limited to the appended claims.

Claims (3)

1. the probability demarcation method of Target near field angle scintillations under motor-driven intersection, is characterized in that, comprise following steps:

Carry out the motor-driven rendezvous simulation of radar and target, obtain the minimum relative distance set { d of the motor-driven rendezvous simulation of radar and target _ti, i=1 ..., N, N are emulation intersection number of times;

Carry out the motor-driven rendezvous simulation of radar and Metal Ball calibration body, obtain the minimum relative distance set { d of the motor-driven rendezvous simulation of radar and Metal Ball calibration body _qi, i=1 ..., N, N are emulation intersection number of times;

Calculate the root mean square σ of the minimum relative distance set of the motor-driven rendezvous simulation of radar and target respectively _t, radar and Metal Ball calibration body the root mean square σ of minimum relative distance set of motor-driven rendezvous simulation _q, and the root mean square σ of random meausrement error of radar system itself _e;

${\mathrm{\σ}}_T=\sqrt{\frac{\underset{i=1}{\overset{N}{\Σ}}{(d_{Ti}-u_T)}^2}{N-1}}---\left(1\right)$

Wherein, u _tfor set { d _tiaverage, N is emulation intersection number of times;

${\mathrm{\σ}}_Q=\sqrt{\frac{\underset{i=1}{\overset{N}{\Σ}}{(d_{Qi}-u_Q)}^2}{N-1}}---\left(2\right)$

Wherein, u _qfor set { d _qiaverage, N is emulation intersection number of times;

${\mathrm{\σ}}_e=\sqrt{\frac{\underset{j=0}{\overset{M}{\Σ}}{\left(e_0\right(t_j)-u_e)}^2}{M}}---\left(3\right)$

Wherein, e ₀(t _j) be random meausrement error, u _efor the average of the random meausrement error of radar system itself, M is the number of discrete time point;

Calculate the relative Calibration result e of Target near field angle scintillations in motor-driven intersection _t;

$e_T=\frac{{\mathrm{\σ}}_T}{{\mathrm{\σ}}_Q}{\mathrm{\σ}}_e---\left(4\right).$

2. the probability demarcation method of Target near field angle scintillations under motor-driven intersection as claimed in claim 1, is characterized in that, carry out the motor-driven rendezvous simulation of radar and target, and the minimum relative distance set obtaining the motor-driven rendezvous simulation of radar and target comprises following steps:

Step S101, calculating line of sight angle, obtain line of sight angle rate of change e'(t in time);

$e^{\′}\left(t_j\right)=\mathrm{\ω}\left(t_j\right)+\frac{e_T(t_j+\mathrm{\Δ}t)+e_0(t_j+\mathrm{\Δ}t)-e_T\left(t_j\right)-e_0\left(t_j\right)}{\mathrm{\Δ}t}---\left(5\right)$

Wherein, t _j=j Δ t is the time discrete value in the motor-driven rendezvous simulation of radar and target, and Δ t is time discrete interval, j=0,1 ..., M, M are the number of discrete time point; ω (t _j) be t _jmoment, target's center was relative to the angular velocity of radar; e _t(t _j) be Target near field angle scintillations, unit is degree; e ₀(t _j) be the random meausrement error of radar system itself, unit is degree, e ₀(t _j) a certain size random number simulation can be utilized to obtain;

Step S102, according to line of sight angle rate of change e'(t in time) calculate the transverse acceleration a (t of radar motion _j);

Step S103, calculating subsequent time t _jduring+Δ t, the speed of related movement vector Δ v of radar and target and relative position Δ s;

Δv＝a(t _j)Δt；

wherein, being average velocity, is moment t _jwith subsequent time t _j+ Δ t speed and 1/2;

Step S104, relative distance according to distance between two points formulae discovery radar and target, circulation emulation, detects radar and target relative distance changes in time, when this relative distance is by when reducing to increase change, namely complete once motor-driven rendezvous simulation, obtain the minimum relative distance of radar and target;

Step S105, impact due to radar random meausrement error, to identical radar and target reference position and speed, the minimum relative distance of the motor-driven rendezvous simulation of different number of times is different, carries out repeatedly motor-driven rendezvous simulation, obtains the minimum relative distance set { d of the motor-driven rendezvous simulation of radar and target _ti, i=1 ..., N, N are emulation intersection number of times.

3. the probability demarcation method of Target near field angle scintillations under motor-driven intersection as claimed in claim 2, it is characterized in that, adopt and obtain the radar method same with the minimum relative distance set of the motor-driven rendezvous simulation of target, carry out the motor-driven rendezvous simulation of radar and Metal Ball calibration body, obtain the minimum relative distance set of the motor-driven rendezvous simulation of radar and Metal Ball calibration body.