CN111175736B

CN111175736B - Point trace correlation distribution method based on quasi-Newton method

Info

Publication number: CN111175736B
Application number: CN202010018377.5A
Authority: CN
Inventors: 崔威威; 姚远; 刘硕; 鲍鹏飞; 张秉致
Original assignee: 724th Research Institute of CSIC
Current assignee: 724th Research Institute of CSIC
Priority date: 2020-01-08
Filing date: 2020-01-08
Publication date: 2022-04-05
Anticipated expiration: 2040-01-08
Also published as: CN111175736A

Abstract

The invention provides a point track correlation distribution method based on a quasi-Newton method, which comprises the steps of firstly, providing a displacement calculation formula of a flight track under the influence of tangential and normal acceleration on the basis of a uniform acceleration model; secondly, decomposing a displacement change formula to reduce the calculation complexity, and establishing an iterative model for solving the tangential acceleration and the normal acceleration based on a quasi-Newton method; constructing an energy formula again to evaluate the influence degree determined by different trace distribution schemes; and finally, giving a lane crossing avoidance rule and a minimum energy rule, optimizing a trace point distribution scheme and preventing trace point distribution errors.

Description

Point trace correlation distribution method based on quasi-Newton method

Technical Field

The invention belongs to the technical field of radar data processing.

Background

The association of the point track and the track is a key problem of multi-sensor tracking, and the stability and the correctness of a track target and the accuracy and the reliability of a track filtering state are determined to a great extent, so that the application guarantee capability of track target data is influenced. The current main data association methods comprise a nearest neighbor method, a global optimum method, a Probability Data Association (PDA), an interactive multi-model, a Joint Probability (JPDA), a neural network and the like, the association method based on the probability theory and the neural network ignores the flight path target navigation dynamics characteristics, the association method based on the probability model needs to calculate the point track membership, the situations of high complexity and poor adaptability exist, and the methods of the interactive multi-model, the neural network and the like are difficult to balance the contradiction between the model complexity and the calculated quantity.

In order to fully utilize track target dynamics characteristics determined by point track distribution, a target displacement change formula determined by tangential and normal acceleration is given by means of a uniform acceleration model, and the track target displacement change formula is split to reduce the calculation difficulty, so that a quasi-Newton iteration calculation model based on a Jacobian matrix is constructed; the invention provides an energy formula to evaluate the reasonable degree of different track distribution schemes, and considers that track crossing conditions possibly exist in adjacent areas, the invention provides track crossing avoidance and minimum energy rules to avoid meeting and even collision of the track under the condition that non-deceleration avoidance measures are not taken, optimize the track distribution scheme and correct track distribution errors.

Disclosure of Invention

The purpose of the invention is: a method for estimating track-point distribution influence, judging track cross meeting track-point track association distribution and scheme adjustment is provided.

The solution of the invention is:

on the basis of analyzing a track target data association processing flow, the invention provides an acceleration evaluation value of the last period, dynamically corrects the size of a wave gate, preliminarily screens out point track data with a potential association relation, thereby obtaining the displacement difference between the point track and the current position of the track, further iteratively calculates the acceleration values of the target in the normal direction and the tangential direction by using a quasi-Newton method, calculates and evaluates the track association influence degree determined by the association point track based on an energy formula provided by the invention, and preliminarily selects the point track with the minimum association degree as an alternative association point track.

Secondly, finding and marking a track target with an adjacent relation through multiple traversals; and (4) performing straddle judgment on the adjacent track pair, and if the current distribution scheme is judged to have the track crossing condition and the time difference of the meeting point of the adjacent track pair is less than 1s, exchanging the point track distribution to avoid ship collision or track batch change.

And after all adjacent track pairs are adjusted, the obtained point track distribution and adjustment results are used as track association results, and finally track updating, filtering and outputting are finished.

Drawings

Fig. 1 is a flow of trace point assignment processing based on quasi-newton method, wherein the dotted line provides the core processing steps of the present invention.

FIG. 2 is a schematic diagram of the determination of the straddle experiment

Fig. 3 is a schematic diagram of adjusted trace point distribution when intersection is determined by a straddle experiment, and the time difference of the intersected track target reaching the intersection point is less than 1 s.

Detailed Description

The method mainly comprises the steps of establishing a target displacement calculation formula, constructing a quasi-Newton iterative calculation model and distributing the point traces based on the acceleration.

(1) Target displacement calculation formula

Due to the fact that the time difference between an unallocated point track and a flight track is usually short, the target data updating rate of a typical navigation radar is usually about 3s, and the data updating rate of an early warning radar isThe rate is higher, the finer period is shorter, therefore, the normal and tangential stress of the target can be assumed to be uniform in a shorter time, namely the normal and tangential acceleration values of the target are not changed, and the invention calculates the tangential acceleration a of the target based on the following formula_tAnd normal acceleration a_n：

(2) quasi-Newton iterative computation model

Due to f₁(a_n,a_t) And f₂(a_n,a_t) The method adopts a quasi-Newton method to estimate the normal and tangential acceleration values of the track target. The quasi-Newton method is to solve a nonlinear equation set:

the numerical value of (a) is solved by (X)₁,x₂,...,x_n) Iterative calculations are performed based on:

X^(K+1)＝X^(K)-F(X^(K))^-1f(X^(K))

where F (X) is a Jacobian matrix. The core difficulty for the problem faced by the present invention is the computation

Thereby constructing a Jacobian matrix

To reduce the computational complexity, the present invention first defines

Therefore, there are:

thus, the following results were obtained:

obtaining a Jacobian matrix

Then, iterative calculations are performed according to the following formula:

when the condition is satisfied

When it is taken

As a numerical solution.

(3) Acceleration-based trace point assignment and adjustment

The change process of the target motion state can be described by acceleration, and the civil ships and aircrafts usually do not have violent speed change in the sailing process, otherwise, larger oil consumption and sailing risks are caused. For this purpose, the invention proposes the velocity and energy change degree determined based on the tangential acceleration and normal acceleration measurement trace distribution, namely the correlation influence degree:

based on the concept of relevance influence, the invention firstly proposes an energy minimum principle, namely a flight path target selects a plurality of point paths to meet min { Eval }_iAnd taking the point trace of | i ═ 1,2,3, …, n } as an alternative associated point trace.

If there are 2 orIf the adjacent tracks do not have route crossing, the route distribution scheme is not adjusted, namely the route distribution scheme is selected to meet min { sum (Eval)_i+Eval_j) The association of the track target and the point track is completed by the distribution scheme of 1,2,3, …, n, i ≠ j }; otherwise, if the tracks are judged to be intersected, the phenomena of collision and batch change of the adjacent tracks under the current point track distribution scheme are caused, and the point track distribution scheme needs to be adjusted.

The invention provides a track target route cross avoidance rule which is mainly provided for near multi-track target data distribution, and because the time difference between unallocated trace points and tracks is usually short, the calculation speed is improved for reducing the calculation complexity. The basic schematic diagram of the straddle experiment is shown in FIG. 2, in which the track O is₁、O₂Has an update position of a and c, an assigned dot trace of b and d, and a velocity of v₁、v₂The following 4 values were calculated:

u＝(c.x-a.x)*(b.y-a.y)-(b.x-a.x)*(c.y-a.y)

v＝(d.x-a.x)*(b.y-a.y)-(b.x-a.x)*(d.y-a.y)

w＝(a.x-c.x)*(d.y-c.y)-(d.x-c.x)*(a.y-c.y)

z＝(b.x-c.x)*(d.y-c.y)-(d.x-c.x)*(b.y-c.y)

when u.v ≦ 0& & w.z ≦ 0, the two routes are intersected.

When the two routes are judged to intersect, the intersection point is solved, and then the target O is solved₁、O₂To the intersection o:

o.x＝[(a.x-b.x)·(c.y·d.x-c.x·d.y)-c.x(c.x-d.x)·(a.y·a.x-a.x·b.y)]/[(a.y-b.y)·(c.x-d.x)-(c.y-d.y)·(a.x-b.x)]

o.y＝[(a.y-b.y)·(c.y·d.x-c.x·d.y)-(c.y-d.x)·(a.y·b.x-a.x·b.y)]/[(a.y-b.y)·(c.x-d.x)-(c.y-d.y)·(a.x-b.x)]

the time difference Δ t thus obtained:

if delta t is less than 1s, the trace point distribution is considered to be wrong, and the distribution scheme is adjusted to be O₁A → d and O₂C → b, as shown in FIG. 3, continue to pick the trace points. Under the condition that the number of the point tracks is more than 1, the original point track with the minimum correlation influence degree is removed from the adjacent point track set of the current track, the distributed point tracks of the adjacent tracks are added, the point track with the minimum correlation influence degree is selected again to serve as the alternative point track of the current track until the two adjacent tracks are ensured not to intersect, and the rule is called a track target route cross avoidance principle.

And after the preliminary distribution and adjustment of the trace point distribution scheme are finished, outputting the correlation result of the track target, and finally finishing the filtering update of the track state.

Claims

1. A point trace correlation distribution method based on a quasi-Newton method is characterized in that:

the method comprises the following steps: based on the assumption of uniform acceleration, a displacement change calculation formula of the flight path under the influence of normal acceleration and tangential acceleration is given:

step two: the displacement variation calculation formula is decomposed into two components:

thereby reducing the calculation difficulty and constructing a Jacobian matrix:

establishing an iterative model based on a quasi-Newton method by initializing a tangential normal acceleration value and giving a termination condition, and if the conditions are met:

obtaining two acceleration values of normal direction and tangential direction

As a numerical solution;

step three: selecting the point track with the minimum energy from the alternative point tracks as a correlation result of the flight track and the point track, wherein an energy formula is calculated according to the following formula:

2. the dot trace correlation distribution method based on quasi-Newton method as claimed in claim 1, wherein: the method comprises the following steps of providing a track cross avoidance principle to solve track distribution errors possibly caused by track cross meeting, firstly judging whether tracks are crossed or not based on a straddle experiment, and if so, solving a track cross point:

and further solving the time difference delta t of the track to the meeting point:

and if the delta t is less than 1s, deleting the current trace from the adjacent trace set by the crossed tracks, adding the trace of the other side, and further performing cross avoidance judgment and trace distribution adjustment on the newly screened trace with the minimum energy until the tracks are not intersected.