CN105388472A - Interlaced and overlapped object tracking method in sea radar system - Google Patents

Abstract

The invention discloses an interlaced and overlapped object tracking method based on situation analysis and feature extraction technologies in a sea radar tracking system. The method is characterized in that situation information around a target ship is established, and character information of other ships around the target ship is simultaneously grasped; whether the target ship is overlapped with other ships (which cannot be distinguished by radar echoes) is judged according to the situation information, merged situation is established for an overlapped target track, character information of the ship merged with the target ship is recorded, and then the merged objects are continuously tracked; and when the merged objects obtained by situation analysis can be distinguished by the radar echoes, the merged objects are divided according to the character information, and the tracking process of the overlapped objects in a complex environment is completed. According to the invention, the situation analysis and character extraction methods are utilized to solve the problem that radar echoes overlap and normal tracking is unavailable, the tracking capability over objects in complex environments such as meeting and interlacing environments is substantially improved.

Description

A kind of to the method for tracking target that is overlapping in extra large radar system

Technical field

The invention belongs to radar target tracking technology, particularly a kind ofly to resolve and the method for tracking target that is overlapping of Feature Extraction Technology based on situation in extra large radar tracking system.

Background technology

Radar target tracking technology all has a wide range of applications in the field such as military, civilian, and typical application example has civilian maritime surveillance (MS), yard craft traffic administration (VTS), air traffic control (ATC) and military to sea police's ring, Shipboard Radar System, air defence system, firepower control and interception guidance etc.What input in radar tracking system is the some mark information formed after the Radar Signal Processing of front end, namely put the object that mark is tracker data processing, and tracker output is the flight path formed after carrying out data processing to target.The radar lock on of summarizing forms primarily of following module: the contents such as the pre-service of some mark, track initiation and termination, data correlation, tracking, and ripple door must be set up in data interconnection and tracing process, the mutual relationship between them can represent with block diagram as shown in Figure 1.Wherein each target lot number carries out identify label.Namely target following is carry out the computings such as interconnected, tracking, filtering, prediction to the measurement data such as target location (as radial distance, orientation), kinematic parameter obtained, to reach the stochastic error suppressing to introduce in measuring process, target of prediction subsequent time position, and form stable targetpath, realize the object of the high precision real-time follow-up to target.Along with the huge advance of calculated performance, the task of radar tracking system is also more and more heavier, the number of tracking target may have hundreds of even thousands of batches simultaneously, follow the tracks of scene also to become increasingly complex, particularly in extra large radar tracking system, in the intensive situation of Sea Surface Ship, situations such as can meeting, interlock, walk abreast occurs often.Because radar resolution is limited, when adjacent ship close together, radar return occurs overlapping, and namely radar cannot have been differentiated target and come.And comparatively slow to extra large target speed, overlapping time is longer, is easy to occur the motor-driven behavior such as turning avoidance, acceleration and deceleration advance in overlay process, and different from original movement tendency, these factors bring very large challenge all to all undoubtedly the lasting tracking of target.Not lose in complex scene tracing process batch, to change batch, the tracking keeping reliable and stable is inspection tracker ability important indicator.

In radar tracking system, ensure that the primary link of correct tenacious tracking is the data correlation problem solving some mark and flight path.The association algorithm used in engineering practice mainly contains optimum nearest neighbor algorithm (NNSF), the interconnected algorithm of probability data (PDA), joint probabilistic data association algorithm (JPDA) and supposes algorithm (MHT) more.But in extra large target overlay process in problems faced, some mark and flight path do not have clear and definite incidence relation, and target is truly put mark and do not existed, and above conventional association algorithm not can solve this boat mismatch problems.Wherein NNSF, PDA, JPDA algorithm can because target generator emotionally condition and occur with the situation of losing in overlay process in tracing process, although MHT algorithm consider around have the situation of a mark, but the relation that target is corresponding with lot number after target is separated cannot be processed, easily there will be and change batch situation, and its calculated amount is huge.

Summary of the invention

The object of the invention is to provide a kind of to the method for tracking target that is overlapping in extra large radar system, for improving extra large target can meet, intersects and tracking power in the complex scenes such as shape.

The technical solution realizing the object of the invention is: concrete steps are:

Step 1: for each target of following the tracks of sets up situation information, namely centered by object ship, searches for relative position and the virtual course speed of a ship or plane information of other ship and this ship around it, and then sets up the situation around target.The object setting up situation grasps closely other ship and the relative position of self and movement tendency, and possibility and the opportunity of echo overlap appear in the anticipation later stage, for likely occurring that overlapping target needs obtained its characteristic information before overlap.The method setting up situation is with reference to International Maritime collision regulation, calculates distance to closest point of approach DCPA when two ships can be met and time to closest point of approach TCPA estimation situation.

Step 2: the characteristic information of other ship around management, sets up and deletes the characteristic information data of other ship by situation information;

Step 3: the target of overlap is set up and merges situation, namely when other ship and this ship on radar return cannot Resolution of Overlapped time, then carry out supervise process with merging phase;

Step 4: monitoring is in the state of motion of the target of merging phase, around the target exploitation be namely combined, situation information judges whether it is separated its radar return, no longer overlapping.

Step 5: split and merge target, namely when the target monitoring merging phase is separated, needs to remove merging phase, enters independently tracked state.Split principle be according to merge before target separately feature mate the degree of approximation with the multiple information of current signature.

In step 1; The method setting up situation is: calculate distance to closest point of approach DCPA when two ships can be met and time to closest point of approach TCPA estimation situation; The calculation procedure calculating situation information distance to closest point of approach DCPA and time to closest point of approach TCPA is as follows:

Step 1-1: determine hunting zone; In tracing process centered by object ship position, search radius is set to r;

Step 1-2: distance to closest point of approach DCPA and being calculated as follows of time to closest point of approach TCPA:

DCPA＝R|sin(C _R-α)|，

TCPA＝R|cos(C _R-α)|/V _R，

V _0x＝V ₀sin(C ₀),

V _Tx＝V _Tsin(C _T)，

V _0y＝V ₀cos(C ₀),

V _Ty＝V _Tcos(C _T)，

$V_R=\sqrt{{(V_{Ty}-V_{0y})}^2+{(V_{Tx}-V_{0x})}^2},$

$C_R=arctan\left(\frac{V_{Tx}-V_{0x}}{V_{Ty}-V_{0y}}\right),$

Wherein, V ₀for the speed of a ship or plane of this ship, V _tfor the speed of a ship or plane of object ship, C ₀for this ship's head, C _tfor target ship's head, V _0x, V _0yrepresent that this ship is at x respectively, the component in y-axis, V _tx, V _tyrepresent that object ship is at x respectively, the component in y-axis, V _rfor the speed of related movement of object ship, C _rfor relative motion course; R is object ship this ship distance relatively, and α is object ship this ship position relatively.

In step 2, clarification of objective information forms primarily of five parts, comprising: target radar returns average amplitude g1, target radar returns gross energy g2, target azimuth expansion g3, target range expansion g4, target speed of a ship or plane information g5, composition characteristic matrix G:

G＝[g1g2g3g4g5]，

When other ship and this ship have close also overlapping trends, add up the characteristic information of other ship, otherwise delete the characteristic information of this ship; Think that both have overlapping trends for the moment when the distance to closest point of approach DCPA calculated and time to closest point of approach TCPA meets following two conditions:

$\left\{\begin{array}{c}DCPA\≤D_0\\ TCPA\≤T_0\end{array}\right.,$

Wherein threshold value D ₀span 0.5Km ~ 1Km, threshold value T ₀span be radar antenna scan period of 10 ~ 20 times.

In step 3, judge whether two targets occur overlapping cases by situation information, take two benches stage tracking strategy for the target after merging, the first stage is within the top n radar antenna scan period of overlay process, target adopts extrapolation tracking mode, i.e. not relating dot mark information; Subordinate phase is take to associate the method for overlapping some mark and then filtering output in the tracing process after N number of cycle; Wherein N=60/T, T represent the radar antenna scan period.

Meet following two conditions according to DCPA and TCPA calculated to think that target is overlapping for the moment in step 3:

$\left\{\begin{array}{c}DCPA\≤D_1\\ TCPA\≤T_1\end{array}\right.,$

Wherein threshold value D ₁value be the minimum resolution distance of 1 ~ 2 times; Threshold value T ₁value be radar antenna scan period of 1 times.

Monitor in step 4 merging phase target be separated time deterministic process as follows:

Step 4-1: judge whether to meet time requirement: the time T that new target occurs ₁at target T overlapping time ₀afterwards, i.e. T ₁> T ₀;

Step 4-2: judge whether meeting spatial status requirement: the position [x that new target occurs ₁y ₁] overlapping with target time position [x ₂y ₂] between distance, delta d meet following two formula simultaneously:

Δd＝v×(T ₁-T ₀)，

$\mathrm{\Δ}d=\sqrt{{(x_1-x_2)}^2+{(y_1-y_2)}^2},$

Wherein speed v ~ [v _min, v _max], v _min=0.5 × v ₀, v _max=2.0 × v ₀;

Step 4-3: judge whether that meeting characteristic similarity requires: the computation process of characteristic similarity α is as follows:

If new target signature matrix is G ₀=[g1g2g3g4g5], overlapping clarification of objective matrix is G _i=[g1'g2'g3'g4'g5'], so otherness matrix K is:

$K=\left[\begin{array}{ccccc}\frac{|g1-{g1}^{\′}|}{g1}& \frac{|g2-{g2}^{\′}|}{g2}& \frac{|g3-{g3}^{\′}|}{g3}& \frac{|g4-{g4}^{\′}|}{g4}& \frac{|g5-{g5}^{\′}|}{g5}\end{array}\right],$

The weight that weighting matrix W=[w1w2w3w4w5] weighs different characteristic information is set, wherein w1+w2+w3+w4+w5=1; As a rule target signature g1, g2 are more stable, and g3, g4 stability is taken second place, and feature g5 poor stability some, therefore the setting of weight matrix also will consider these factors, is traditionally arranged to be w1=w2=0.25, w3=w4=0.2, w5=0.1.

So characteristic similarity α is:

α＝1-KW

α span is 0 ~ 1;

New target answers α to be greater than certain thresholding with overlapping target similarity, then judge that it is separated by the target after merging, the usual value of threshold value is greater than more than 0.6.

In step 5, the principle of fractionation be according to the target before merging separately feature mate the degree of approximation with the multiple information of current signature.

The present invention is based on the method for tracking target of situation parsing and Feature Extraction Technology, by the situation set up and more around fresh target, realize the anticipation following the tracks of scene, information search and decision-making, the characteristic information (comprising mean intensity, gross energy, orientation expansion, extended distance, movable information) simultaneously making full use of target self carries out aid decision making and identification, completes target and overlaps onto in detachment process and follow the tracks of continually and steadily.

Compared with prior art, its remarkable advantage is in the present invention: (1), for complex scenes such as can meeting the target occurred in extra large radar tracking system, intersect, walk abreast, provides complete effective solution.(2) by setting up situation information, situation possible in anticipation object tracking process and then take to be different from traditional tracking strategy; When target close proximity, radar cannot be differentiated, and the echo meeting overlapping long period, traditional tracking there is no this prior imformation and then can affect normal tracking.(3) completed the correspondence of target identities by target diverse characteristics information, effectively solve the marriage problem after overlapping target is separated.(4) only for there being the target of overlapping trends to carry out special processing, the calculated amount that overall plan increases is little, is easy to engineering realizes.

Accompanying drawing explanation

To do the present invention below in conjunction with the drawings and specific embodiments and further illustrate, above-mentioned and/or otherwise advantage of the present invention will become apparent.

Fig. 1 radar tracking system data processing schematic block diagram.

Fig. 2 the present invention is to a kind of in extra large radar tracking system process flow diagram of the method for tracking target that is overlapping.

Fig. 3 target situation computational mathematics model schematic.

The embodiment that Fig. 4 the present invention applies in certain radar tracking system follows the tracks of sectional drawing.

Embodiment

Composition graphs 2, the present invention is a kind of to the method for tracking target that is overlapping in extra large radar system, comprises the following steps:

The first step, in tracing process centered by object ship, search relative position and the virtual course speed of a ship or plane information of other ships around it, set up the situation information of this object ship, wherein search radius r is relevant with the radar antenna cycle, the cycle search radius of longer correspondence is larger, is generally arranged between 1 ~ 5Km.The object setting up situation to grasp around other target and the relative position of self and movement tendency, and possibility and the opportunity of echo overlap appear in the anticipation later stage.This method, by calculating the prior imformation obtained, for likely occurring that overlapping target obtained its characteristic information before overlap, plays a role in follow-up pairing process.The method setting up situation in the present invention is with reference to International Maritime collision regulation, calculates distance to closest point of approach DCPA when two ships can be met and time to closest point of approach TCPA estimation situation.

(1) namely distance to closest point of approach DCPA is minimum by distance when can meet of calculating two ship, and DCPA is the major criterion whether measurement two ship will meet, and DCPA is less, illustrates that two ships occur that overlapping possibility is larger; Namely time to closest point of approach TCPA is the time that two ships arrive least meeting distance point, and with regard to TCPA, TCPA is larger, shows that two ships occur that overlapping possibility is less; TCPA is less, then show that overlapping possibility is larger.Its mathematical model as shown in Figure 3, calculates under derivation:

If V ₀, V _t, C ₀, C _tbe respectively the speed of a ship or plane of this ship and object ship, course.V _0x, V _tx, V _0y, V _tyrepresent that this ship and object ship are at x respectively, the component in y-axis, can obtain

V _0x＝V ₀sin(C ₀),V _Tx＝V _Tsin(C _T)

V _0y＝V ₀cos(C ₀),V _Ty＝V _Tcos(C _T)

$V_R=\sqrt{{(V_{Ty}-V_{0y})}^2+{(V_{Tx}-V_{0x})}^2}$

$C_R=arctan\left(\frac{V_{Tx}-V_{0x}}{V_{Ty}-V_{0y}}\right)$

V _rfor the speed of related movement of object ship, C _rfor relative motion course, then

DCPA＝R|sin(C _R-α)|

TCPA＝R|cos(C _R-α)|/V _R

Wherein, R is target this ship distance relatively, and α is target this ship position relatively.

Second step, management is other clarification of objective information around, is namely set up in time by situation information and delete other clarification of objective information data.Clarification of objective information forms primarily of five parts, comprising: target radar returns average amplitude, target radar returns gross energy, target azimuth expansion, target range expansion, target speed of a ship or plane information.Composition characteristic matrix G, is expressed as follows:

G＝[g1g2g3g4g5]

When other ship and when self having close also overlapping trends, add up the characteristic information of this ship; And both characteristic informations that are distant or that be in away from deleting this ship during trend.Wherein think that both have overlapping trends for the moment when DCPA and TCPA calculated meets following two conditions:

$\left\{\begin{array}{c}DCPA\≤D_0\\ TCPA\≤T_0\end{array}\right.$

Wherein D ₀span is generally 0.5Km ~ 1Km, T ₀span be radar antenna scan period of 10 ~ 20 times.

3rd step: " merging " situation is set up to the target of overlap, namely when other ship and this ship on radar return cannot Resolution of Overlapped time, then carry out supervise process with merging phase.By situation information, this method judges whether two targets occur overlapping cases, below DCPA and TCPA calculated meets, a period of time of two conditions then thinks that target is overlapping:

$\left\{\begin{array}{c}DCPA\≤D_1\\ TCPA\≤T_1\end{array}\right.$

Wherein threshold value D ₁value be the minimum resolution distance of 1 ~ 2 times; Threshold value T ₁value be radar antenna scan period of 1 times.

Target overlapping period is due to radar return aliasing, the point mark information that radar front end signal transacting exports differs larger with actual position, the point mark can not directly simply brought as target carries out related quantities process, consider that overlapping period target is easy to occur the motor-driven behavior such as turning avoidance, acceleration and deceleration advance again simultaneously, with original movement tendency, therefore also need in tracing process, immediately following the echo center after overlap, to prevent with losing target.In this law, tracking strategy is stage by stage taked for the target after merging:

1, within the top n radar antenna scan period of overlay process, consider extra large target velocity slower, the motor-driven cycle is longer, movement tendency in short time is with original approximate, target adopts " extrapolation " tracking mode, i.e. not relating dot mark information, the value N=60/T relevant to the radar antenna cycle of N;

2, considering that target travel trend may change in the tracing process after N number of cycle, continue extrapolation and likely depart from real trace, therefore take to associate overlapping some mark and then the method for filtering, ensureing that target is with losing.In this stage because overlapping target association is to identical some mark, flight path can be very approximate.

It may be noted that no matter in which in stage, if according to situation monitor overlapping target be separated time, target all needs to enter the 5th step.

4th step, monitoring is in the state of motion of merging phase target, and around the target exploitation be namely combined, situation information judges whether it is separated its radar return, no longer overlapping.In the present invention by track initiation management method monitoring objective be separated.When having new track initiation around merging target, first judge whether newly initial target is merge target to be separated causing of reason, and judgment criterion has following several aspect:

1, time criterion;

Separate if new target is the target after merging, so must meet the time T that new target occurs ₁should at target T overlapping time ₀afterwards, i.e. T ₁> T ₀;

2, location criteria;

Separate if new target is the target after merging, the position [x that new target occurs ₁y ₁] overlapping with target time position [x ₂y ₂] between distance produce primarily of the motion of target at overlay process, therefore Δ d within limits, should meet following formula:

Δd＝v×(T ₁-T ₀)

Wherein speed v ~ [v _min, v _max], v _minv _maxvalue and the speed v of new target when occurring ₀relevant, be usually located at as v _min=0.5 × v ₀, and v _max=2.0 × v ₀.T ₀, T ₁when being namely the target overlap mentioned in above-mentioned time criterion, time and fresh target go out current time.

3, feature criterion

Separate if new target is the target after merging, new clarification of objective characteristically should meet certain similarity with the some targets in overlapping target.The computation process of characteristic similarity α is as follows:

If new target signature matrix is G ₀=[g1g2g3g4g5], overlapping clarification of objective matrix is G _i=[g1'g2'g3'g4'g5'], so otherness matrix K is:

$K=\left[\begin{array}{ccccc}\frac{|g1-{g1}^{\′}|}{g1}& \frac{|g2-{g2}^{\′}|}{g2}& \frac{|g3-{g3}^{\′}|}{g3}& \frac{|g4-{g4}^{\′}|}{g4}& \frac{|g5-{g5}^{\′}|}{g5}\end{array}\right]$

Consider the stability difference of diverse characteristics information, the weight that weighting matrix W=[w1w2w3w4w5] weighs different characteristic information is set, wherein w1+w2+w3+w4+w5=1.As a rule target signature g1, g2 are more stable, and g3, g4 stability is taken second place, and feature g5 poor stability some, therefore the setting of weight matrix also will consider these factors, is traditionally arranged to be w1=w2=0.25, w3=w4=0.2, w5=0.1.

So characteristic similarity α is:

α＝1-KW

α span is 0 ~ 1.

New target and overlapping target similarity should be greater than certain thresholding and just think that it is separated by the target after merging, and can arrange, be set to 0.7 when the present invention applies in engineering according to actual conditions.

5th step: split and merge target, when the target monitoring merging phase is separated, needs to remove merging phase, enters independently tracked state.Split principle be according to merge before target separately feature mate the degree of approximation with the multiple information of current signature.Merge front two targets and the current clarification of objective similarity separated by calculating respectively, computing method are with reference to the process of the 4th step.Computation process is as follows:

If new target signature matrix is G ₀, overlapping clarification of objective matrix is G respectively ₁and G ₂, the otherness matrix so calculated is respectively K ₁and K ₂, and then according to formula α=1-KW, calculate characteristic similarity and be respectively α ₁and α ₂.Comparative feature similarity α ₁and α ₂value, namely that target that similarity is larger is separating in merging process, and tracking mode all needs the target transferring to the place of separation to get on tracking lot number, thus completes the process of fractionation, enters independently tracked state.

Illustrate below in conjunction with Fig. 4 (due to singularity of the present invention, can only represent with gray-scale map form), further illustrate the present invention by the embodiment applied in engineering and effect assessment thereof.Fig. 4 is that certain is to the radar asorbing paint screen shot in extra large radar tracking process, two tracking target lot numbers are respectively A08001 and A08002, can see in figure that two target appearance can meet situation in tracing process, target echo occurs overlapping, and all turns to maneuver in overlapping period two target.Adopt the method for tracking target that is overlapping that the present invention proposes, target can normally be followed the tracks of, and does not occur changing batch situation, demonstrate validity and the practicality of this method by two target lot numbers in AIS information contrast tracing process.

The invention provides a kind of to the method for tracking target that is overlapping in extra large radar system; the method and access of this technical scheme of specific implementation is a lot; the above is only the preferred embodiment of the present invention; should be understood that; for those skilled in the art; under the premise without departing from the principles of the invention, can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.The all available prior art of each ingredient not clear and definite in the present embodiment is realized.

Claims (7)

1., to the method for tracking target that is overlapping in extra large radar system, it is characterized in that, have the following steps in tracing process:

Step 1: for each target of following the tracks of sets up situation information, namely centered by object ship, searches for relative position and the virtual course speed of a ship or plane information of other ship and this ship around it, and then sets up the situation around target;

Step 2: management around other target is the characteristic information of other ship around, is set up and delete other clarification of objective information data by situation information;

Step 3: the target of overlap is set up and merges situation, namely when other ship and this ship on radar return cannot Resolution of Overlapped time, then carry out supervise process with merging phase;

Step 4: monitoring is in the state of motion of the object ship of merging phase, and around the target exploitation be namely combined, situation information judges whether its radar return is separated with overlapping ship;

Step 5: split and merge target, namely when the target monitoring merging phase is separated, removes merging phase, enters independently tracked state.

2. method according to claim 1, is characterized in that, in step 1; The method setting up situation is: calculate distance to closest point of approach DCPA when two ships can be met and time to closest point of approach TCPA estimation situation; The calculation procedure calculating situation information distance to closest point of approach DCPA and time to closest point of approach TCPA is as follows:

Step 1-1: determine hunting zone; In tracing process centered by object ship position, search radius is set to r;

Step 1-2: distance to closest point of approach DCPA and being calculated as follows of time to closest point of approach TCPA:

DCPA＝R|sin(C _R-α)|，

TCPA＝R|cos(C _R-α)|/V _R，

V _0x＝V ₀sin(C ₀),

V _Tx＝V _Tsin(C _T)，

V _0y＝V ₀cos(C ₀),

V _Ty＝V _Tcos(C _T)，

$V_R=\sqrt{{(V_{Ty}-V_{0y})}^2+{(V_{Tx}-V_{0x})}^2},$

$C_R=arctan\left(\frac{V_{Tx}-V_{0x}}{V_{Ty}-V_{0y}}\right),$

Wherein, V ₀for the speed of a ship or plane of this ship, V _tfor the speed of a ship or plane of object ship, C ₀for this ship's head, C _tfor target ship's head, V _0x, V _0yrepresent that this ship is at x respectively, the component in y-axis, V _tx, V _tyrepresent that object ship is at x respectively, the component in y-axis, V _rfor the speed of related movement of object ship, C _rfor relative motion course; R is object ship this ship distance relatively, and α is object ship this ship position relatively.

3. method according to claim 1, it is characterized in that, in step 2, clarification of objective information forms primarily of five parts, comprise: target radar returns average amplitude g1, target radar returns gross energy g2, target azimuth expansion g3, target range expansion g4, target speed of a ship or plane information g5, composition characteristic matrix G:

G＝[g1g2g3g4g5]，

When other ship and this ship have close also overlapping trends, add up the characteristic information of other ship, otherwise delete the characteristic information of this ship; Think that both have overlapping trends for the moment when the distance to closest point of approach DCPA calculated and time to closest point of approach TCPA meets following two conditions:

$\left\{\begin{array}{c}DCPA\≤D_0\\ TCPA\≤T_0\end{array}\right.,$

Wherein threshold value D ₀span 0.5Km ~ 1Km, threshold value T ₀span be radar antenna scan period of 10 ~ 20 times.

4. method according to claim 1, it is characterized in that, in step 3, judge whether two targets occur overlapping cases by situation information, two benches stage tracking strategy is taked for the target after merging, first stage is within the top n radar antenna scan period of overlay process, and target adopts extrapolation tracking mode, i.e. not relating dot mark information; Subordinate phase is take to associate the method for overlapping some mark and then filtering output in the tracing process after N number of cycle; Wherein N=60/T, T represent the radar antenna scan period.

5. method according to claim 1, is characterized in that, is to meet following two conditions according to DCPA and TCPA calculated to think that target is overlapping for the moment in step 3:

$\left\{\begin{array}{c}DCPA\≤D_1\\ TCPA\≤T_1\end{array}\right.,$

Wherein threshold value D ₁value be the minimum resolution distance of 1 ~ 2 times; Threshold value T ₁value be radar antenna scan period of 1 times.

6. method according to claim 1, is characterized in that, monitor in step 4 merging phase target be separated time deterministic process as follows:

Step 4-1: judge whether to meet time requirement: the time T that new target occurs ₁at target T overlapping time ₀afterwards, i.e. T ₁> T ₀;

Step 4-2: judge whether meeting spatial status requirement: the position [x that new target occurs ₁y ₁] overlapping with target time position [x ₂y ₂] between distance, delta d meet following two formula simultaneously:

Δd＝v×(T ₁-T ₀)，

$\mathrm{\Δ}d=\sqrt{{(x_1-x_2)}^2+{(y_1-y_2)}^2},$

Wherein speed v ~ [v _min, v _max], v _min=0.5 × v ₀, v _max=2.0 × v ₀;

Step 4-3: judge whether that meeting characteristic similarity requires: the computation process of characteristic similarity α is as follows:

If new target signature matrix is G ₀=[g1g2g3g4g5], overlapping clarification of objective matrix is G _i=[g1'g2'g3'g4'g5'], so otherness matrix K is:

$K=\[\frac{\left|g1-g{1}^{\′}\right|}{g1}\frac{\left|g2-{g^2}^{\′}\right|}{g2}\frac{\left|g3-g{3}^{\′}\right|}{g3}\frac{\left|g4-g{4}^{\′}\right|}{g4}\frac{\left|g5-g{5}^{\′}\right|}{g5}\],$

The weight that weighting matrix W=[w1w2w3w4w5] weighs different characteristic information is set, wherein w1+w2+w3+w4+w5=1;

Characteristic similarity α is:

α＝1-KW，

α span is 0 ~ 1;

New target answers α to be greater than certain thresholding with overlapping target similarity, then judge that it is separated by the target after merging, thresholding value is greater than more than 0.6.

7. method according to claim 1, is characterized in that, in step 5, the principle of fractionation be according to the target before merging separately feature mate the degree of approximation with the multiple information of current signature.