CN105676200A - Parameter extraction method for precession target structure - Google Patents

Abstract

The present invention discloses a parameter extraction method for a precession target structure. The method is characterized by comprising the steps of respectively acquiring the target radial length information of two radars based on the target one-dimensional range profiles of the two radars; according to the target radial length information, calculating the target radial length curves of the two radars; according to the target radial length curves of the two radars, calculating the target precession angles and the precession axis aspect angle difference of the two radars; according to the target precession angles, the precession axis aspect angle difference of the two radars and the target radial length curves of the two radars; calculating a target length and a target bottom-surface radius. Compared with the prior art, the structure parameters and the precession angles of cooperative targets and non-cooperative targets can be extracted at a relatively accuracy error. Meanwhile, the observation time required for extracting precession characteristics is greatly shortened.

Description

Precession object construction parameter extracting method

Technical field

The present invention relates to target's feature-extraction field, particularly relate to a kind of precession object construction parameter extracting method.

Background technology

Ballistic missile stage casing has the features such as the flight time is longer, spatial environments is relatively easy relative to motors in boost phase penetration and reentry stage, is the important stage of Attack Defence. Bullet constitutes the fine motion characteristic of bullet target at forms of motion such as the spin in stage casing, precession, it is possible to identify other key character as bullet classification. For precession target, its cyclophysis is fairly obvious, its RCS (RadarCrossSection, RCS) cycle that rises and falls is consistent with precession period, and its precession period can be obtained by arrowband RCS, but the angle of precession of target and structural information cannot be directly obtained by target RCS.

Current precession clarification of objective extracting method obtains mainly by target RCS or target one-dimensional range profile, and the two information obtained mainly by single radar is extracted. The former is by carrying out fitting of a polynomial to target RCS, utilize the RCS estimation equation of circular cone as the Template Information of target to extract precession parameter, however it is necessary that and understand target RCS characteristic under various attitudes or bullet classification target shape, being not particularly suited for noncooperative target, limitation is bigger; Second method be by target one-dimensional range profile ask for radical length or reconstruct target scattering center extract precession feature, however it is necessary that longer observation time and error are bigger.

Therefore, need badly a kind of suitable in noncooperative target, do not rely on longer observation time and the less precession object construction parameter extracting method of error to solve the problems referred to above.

Summary of the invention

The invention provides a kind of precession object construction parameter extracting method, the echo data that multi-section radar observes at short notice is utilized to obtain target radial length information, obtain target radial length curve by curve matching, extract target length and bottom surface radius on this basis. Compared with prior art, the present invention can accurately extract structural parameters and the angle of precession of cooperation/noncooperative target with less error, significantly reduces the observation time extracted needed for precession feature simultaneously.

The present invention provides a kind of precession object construction parameter extracting method, including: S1. obtains the first radar target radical length information by the target one-dimensional range profile of the first radar;The second radar target radical length information is obtained by the target one-dimensional range profile of the second radar; S2. the first radar target radical length curve is calculated according to the first radar target radical length information; The second radar target radical length curve is calculated according to the second radar target radical length information; S3. the first radar target radical length curve and the second radar target radical length curve is utilized to calculate the precession axis angle of sight difference of target angle of precession and the first radar and the second radar; S4. based target angle of precession, precession axis angle of sight difference, the first radar target radical length curve and the second radar target radical length curve calculate target length and target bottom surface radius; The described precession axis angle of sight is the angle of radar line of sight and target precession axis.

Preferably, step S3 specifically includes: S31. utilizes the first radar target radical length curve, the second radar target radical length curve and formula 1 to calculate target angle of precession;

$tg\mathrm{\θ}=\sqrt{\frac{Y_1^2-Y_2^2}{X_2^2-X_1^2}}$ Formula 1

S32. the first radar target radical length curve, the second radar target radical length curve, target angle of precession and formula 2 is utilized to calculate the precession axis angle of sight difference of the first radar and the second radar;

$tg({\mathrm{\β}}_i-{\mathrm{\α}}_i)=\frac{X_1{Y}_2-Y_1{X}_2}{\sin \mathrm{\θ}\cos \mathrm{\θ}\[\frac{X_1{X}_2}{{\cos }^2\mathrm{\θ}}+\frac{Y_1{Y}_2}{{\sin }^2\mathrm{\θ}}\]}$ Formula 2

Wherein, θ is target angle of precession; X₁It is that the first radar is at first time period T₁In, the sum of the maxima and minima of target radial length; Y₁It is that the first radar is at first time period T₁In, the difference of the maxima and minima of target radial length; X₂It is that the second radar is at the second time period T₂In, the sum of the maxima and minima of target radial length; Y₂It is that the second radar is at the second time period T₂In, the difference of the maxima and minima of target radial length; α_iIt is the precession axis angle of sight of the first radar, and α_iArrange from 0 ° to 90 ° according to the first step value; β_iFor with α_iThe precession axis angle of sight of the second corresponding radar; I > 1 and i ∈ N.

Preferably, step S4 specifically includes: S41. based target angle of precession, precession axis angle of sight difference and formula 3, formula 4 calculate corresponding to each first radar precession axis angle of sight α_iTarget sample length L_iAnd target sample bottom surface radius R_i;

$\left[\begin{array}{c}Len\left(T_{11}\right)\\ ...\\ Len\left(T_{1N}\right)\\ Len\left(T_{21}\right)\\ ...\\ Len\left(T_{2M}\right)\end{array}\right]=A\left[\begin{array}{c}{L}_i\\ R_i\end{array}\right]$ Formula 3

Wherein,

Formula 4

S42. according to target sample length L_iAnd target sample bottom surface radius R_iExtract target length and target bottom surface radius;

Wherein, T₁₁…T_1NFor T₁Interior N number of time point, T₂₁…T_2MFor T₂M interior time point; M > 1, N > 1, M ∈ N, N ∈ N; Len (T₁₁)…Len(T_1N) be and T₁₁…T_1NCorresponding target radial length, Len (T₂₁)…Len(T_2M) be and T₂₁…T_2MCorresponding target radial length; ω is target angular velocity of precession;Respectively the first radar, target precession initial phase angle under the second radar visual angle; τ₁₁…τ_1NFor with T₁₁…T_1NThe first corresponding radar line of sight angle, τ₂₁…τ_2MFor with T₂₁…T_2MThe second corresponding radar line of sight angle; And

Preferably, step S42 specifically includes: S421. calculates each group of target sample length R according to formula 5_iAnd target sample bottom surface radius L_iError amount e (α_i);

$e\left({\mathrm{\α}}_i\right)={\left|\right|A\left[\begin{array}{c}{L}_i\\ R_i\end{array}\right]-\left[\begin{array}{c}\mathrm{Len}\left(T_{11}\right)\\ ...\\ \mathrm{Len}\left(T_{1N}\right)\\ \mathrm{Len}\left(T_{21}\right)\\ ...\\ \mathrm{Len}\left(T_{2M}\right)\end{array}\right]\left|\right|}^2$ Formula 5

S422. compare the size of all error amounts, and extract target sample length corresponding to minimum error amount as target length, extract target sample bottom surface radius corresponding to minimum error amount as target bottom surface radius.

Preferably, step S2 specifically includes: S21. is according to the first radar target radical length information, it is determined that the parameter l of the first radar target radical length curve₁₁、l₁₂、Span; According to the second radar target radical length information, it is determined that the parameter l of the second radar target radical length curve₂₁、l₂₂、Span;S22. based on l₁₁、l₁₂、Span and required precision, arrange respectively with l₁₁、l₁₂、Corresponding value interval, to l₁₁、l₁₂、Carry out discrete value, generate l₁₁、l₁₂、Parameter array; And based on l₂₁、l₂₂、Span and required precision, arrange respectively with l₂₁、l₂₂、Corresponding value interval, to l₂₁、l₂₂、Carry out discrete value, generate l₂₁、l₂₂、Parameter array; S23. the target radial length information and the formula 6 that utilize the first radar acquisition check l₁₁、l₁₂、Parameter array; The parameter of the first radar target radical length curve is determined according to testing result; And utilize the target radial length information of the second radar acquisition and formula 7 to check l₂₁、l₂₂、Parameter array; The parameter of the second radar target radical length curve is determined according to testing result;

Formula 6

Formula 7

The target radial length information that described first radar obtains includes time point t₁₁…t_1PAnd the target radial length Len (t corresponding with this time point₁₁)…Len(t_1P); The target radial length information that described second radar obtains includes time point t₂₁…t_2QAnd the target radial length Len (t corresponding with this time point₂₁)…Len(t_2Q); P > 1, Q > 1, P ∈ N, Q ∈ N.

Preferably, step S23 specifically includes: S231. chooses l₁₁、l₁₂、Arbitrary array in parameter array, by t₁₁…t_1PAnd this arbitrary array substitutes into formula 6, obtain P operation result; Calculate P operation result and Len (t respectively₁₁)…Len(t_1P) difference, obtain l₁₁、l₁₂、P difference of this arbitrary array in parameter array; And choose l₂₁、l₂₂、Arbitrary array in parameter array, by t₂₁…t_2QAnd this arbitrary array substitutes into formula 7, obtain Q operation result; Calculate Q operation result and Len (t respectively₂₁)…Len(t_2Q) difference, obtain l₂₁、l₂₂、Q difference of this arbitrary array in parameter array;

S232. l is compared₁₁、l₁₂、The size of P difference of arbitrary array and first threshold in parameter array, adds up the difference quantities less than first threshold in P difference, and using this difference quantities as l₁₁、l₁₂、The passing number of this arbitrary array in parameter array; And compare l₂₁、l₂₂、The size of Q difference of arbitrary array and Second Threshold in parameter array, adds up the difference quantities less than Second Threshold in Q difference, and using this difference quantities as l₂₁、l₂₂、The passing number of this arbitrary array in parameter array;

S233. l is chosen₁₁、l₁₂、The array that in parameter array, passing number is maximum, using the parameter of this array parameter as the first radar target radical length curve; And choose l₂₁、l₂₂、The array that in parameter array, passing number is maximum, using the parameter of this array parameter as the second radar target radical length curve; Described first threshold requires to arrange according to the first radar accuracy; Described Second Threshold requires to arrange according to the second radar accuracy.

Preferably, step S1 is particularly as follows: by the target one-dimensional range profile of the first radar, utilize optimal path method to obtain the first radar target radical length information; By the target one-dimensional range profile of the second radar, optimal path method is utilized to obtain the second radar target radical length information.

Preferably, before step S1, described method also includes, and: S0. appoints from U portion radar and takes two and be combined into one group, forms V group radar; Target length L is extracted according to two radars in described V group radar arbitrary group_jAnd target bottom surface radius R_j; After step s4, described method also includes: S5. is according to target length L_jAnd target bottom surface radius R_jCalculate optimum target length and optimum target bottom surface radius; Wherein, U > 2, and U ∈ N;1≤j≤V, and j ∈ N.

Preferably, step S5 is particularly as follows: calculate L according to formula 8_jMeansigma methods L^#, by L_jMeansigma methods L^#As optimum target length;R is calculated according to formula 9_jMeansigma methods R^#, by R_jMeansigma methods R^#As optimum target bottom surface radius;

$L^{\#}=\frac{\underset{j=1}{\overset{V}{\Σ}}{L}_j}{V}$ Formula 8

$R^{\#}=\frac{\underset{j=1}{\overset{V}{\Σ}}{R}_j}{V}$ Formula 9.

Preferably, step S5 is particularly as follows: calculate L according to formula 10_jWeighted mean L^*, by L_jWeighted mean L^*As optimum target length; R is calculated according to formula 11_jWeighted mean R^*, by R_jWeighted mean R^*As optimum target bottom surface radius;

$L*=\frac{\underset{j=1}{\overset{V}{\Σ}}{W}_j{L}_j}{\underset{j=1}{\overset{V}{\Σ}}{W}_j}$ Formula 10

$R*=\frac{\underset{j=1}{\overset{V}{\Σ}}{W}_j{R}_j}{\underset{j=1}{\overset{V}{\Σ}}{W}_j}$ Formula 11

Wherein, W_jFor the weights of jth group radar, W in V group radar_jDetermined by the performance parameter of each radar in two radars in jth group.

According to precession object construction parameter extracting method provided by the invention, it is possible to accurately extract structural parameters and the angle of precession of cooperation/noncooperative target with less error, significantly reduce the observation time extracted needed for precession feature simultaneously.

Accompanying drawing explanation

Fig. 1 is the precession object module figure of the precession object construction parameter extracting method of the present invention;

Fig. 2 is the first pass figure of the precession object construction parameter extracting method of the present invention;

Fig. 3 is the second flow chart of the precession object construction parameter extracting method of the present invention.

Detailed description of the invention

For making the purpose of the present invention, technical scheme and advantage clearly understand, referring to accompanying drawing and enumerate preferred embodiment, the present invention is described in more detail. However, it is necessary to illustrate, the many details listed in description are only used to make reader that one or more aspects of the present invention are had a thorough explanation, can also realize the aspects of the invention even without these specific details.

Precession object construction parameter extracting method of the prior art is used for cooperative target, and its observation time is longer and error is bigger.

For above-mentioned technical problem, the invention provides a kind of precession object construction parameter extracting method based on many radars, can accurately extract structural parameters and the angle of precession of cooperation/noncooperative target with less error, significantly reduce the observation time extracted needed for precession feature simultaneously.

Fig. 1 is the precession object module figure of the present invention. In a preferred embodiment of the invention, precession target is circular cone target. O₂-x_Ry_Rz_RConstitute radar fix system, O₁-x_jy_jz_jConstitute precession axis coordinate system; In precession axis coordinate system, with target precession center for initial point, target precession axis is X_jAxle, Z_jAxle is at electromagnetic wave incident direction and X_jIn the plane that axle is constituted, x_jAxle and y_jAxle, z_jAxle constitutes right-handed helix; Owing to there is the angle of attack, therefore target precession axis and target velocity direction inconsistent.

Target length in Fig. 1 is L, and bottom surface radius is R, then target semi-cone angle ε=tan^-1(R/L), target body shaft rotates with angular speed ω, angle of precession θ counterclockwise around precession axis, and the initial phase angle of vertex of a cone precession isIn radar fix system, the angle (the precession axis angle of sight) of the sight line of radar Ra and target precession axis is α, is τ with the angle (i.e. radar line of sight angle) of body shaft. The circular cone target vertex of a cone is L to precession center distance₁, precession center is L to the distance at the cone end₂, it is clear that there is L=L₁+L₂. Theoretical according to scattering center, when electromagnetic wave forward direction incidence, circular cone target has three strong scattering centers, respectively vertex of a cone scattering center P₁, two cone feather edge scattering center P₂And P₃。

In t, the unit vector that precession center is constituted with vertex of a cone P1 is:

The unit vector that radar line of sight is constituted with precession center is:

RaO₁=[cos α, 0 ,-sin α ,]

Then O₁P₁And RaO₁Angle be radar line of sight angle, and be apparent from:

Target radial length is two scattering centers projector distance diametrically of lie farthest away in one-dimensional range profile.Making precession center is phase place zero point, and f () represents project, then three scattering centers of circular cone target are respectively as follows: at radar projected position radially

f([P₁,P₂,P₃])=[L₁cosτ,-L₂cosτ+Rsinτ,-L₂cosτ-Rsinτ]

According to Electromagnetic Scattering Theory, when radar line of sight angle is more than target semi-cone angle, scattering center P3 is blocked and invisible. And in the ordinary course of things, owing to being affected by the angle of attack, radar line of sight angle is more than circular cone target semi-cone angle, therefore scattering center P₃It is difficult to be observed. Then circular cone target radial length is scattering center P₁To P₂Radially projecting's distance:

f(P₁)-f(P₂)=L₁cosτ+L₂cosτ-Rsinτ

=Lcos τ-Rsin τ

Owing to radar line of sight angle changes over, therefore radical length is also a time dependent sequence, and making radical length is Len (t), then it meets below equation group:

Formula 12

In actual applications, R is much smaller than L, then:

Formula 13

Make l₁=Lcos θ cos α, l₂=Lsin θ sin α, then:

Formula 14

Wherein ω can be obtained by narrow band analyzing, and the unknown parameter of above-mentioned equation is l₁、l₂、

So far obtain radical length theoretical formula and the practical application formula of circular cone target, on this basis, the invention provides a kind of precession object construction parameter extracting method, as in figure 2 it is shown, include:

S1. the first radar target radical length information is obtained by the target one-dimensional range profile of the first radar; The second radar target radical length information is obtained by the target one-dimensional range profile of the second radar.

In a preferred embodiment of the invention, step S1 particularly as follows:

By the target one-dimensional range profile of the first radar, optimal path method is utilized to obtain the first radar target radical length information; By the target one-dimensional range profile of the second radar, optimal path method is utilized to obtain the second radar target radical length information. Optimal path method effectively can extract target radial length information from target one-dimensional range profile, also can guarantee that higher accuracy rate in strong noise environment.

S2. the first radar target radical length curve is calculated according to the first radar target radical length information;

The second radar target radical length curve is calculated according to the second radar target radical length information.

In a preferred embodiment of the invention, step S2 specifically includes:

S21. according to the first radar target radical length information, it is determined that the parameter l of the first radar target radical length curve₁₁、l₁₂、Span; According to the second radar target radical length information, it is determined that the parameter l of the second radar target radical length curve₂₁、l₂₂、Span.

S22. based on l₁₁、l₁₂、Span and required precision, arrange respectively with l₁₁、l₁₂、Corresponding value interval, to l₁₁、l₁₂、Carry out discrete value, generate l₁₁、l₁₂、Parameter array; Above-mentioned l₁₁、l₁₂、Parameter array comprises all l after discrete value₁₁、l₁₂、Combination, arbitrary array therein is all the undetermined parameter of the first radar target radical length curve;

Further, based on l₂₁、l₂₂、Span and required precision, arrange respectively with l₂₁、l₂₂、Corresponding value interval, to l₂₁、l₂₂、Carry out discrete value, generate l₂₁、l₂₂、Parameter array; Above-mentioned l₂₁、l₂₂、Parameter array comprises all l after discrete value₂₁、l₂₂、Combination, arbitrary array therein is all the undetermined parameter of the second radar target radical length curve.

S23. the target radial length information and the formula 6 that utilize the first radar acquisition check l₁₁、l₁₂、Parameter array; The parameter of the first radar target radical length curve is determined according to testing result; And

The target radial length information and the formula 7 that utilize the second radar acquisition check l₂₁、l₂₂、Parameter array; The parameter of the second radar target radical length curve is determined according to testing result;

Formula 6

Formula 7

Formula 6, formula 7 are obtained by aforementioned formula 14;

The target radial length information that first radar obtains includes time point t₁₁…t_1PAnd the target radial length Len (t corresponding with this time point₁₁)…Len(t_1P);

The target radial length information that second radar obtains includes time point t₂₁…t_2QAnd the target radial length Len (t corresponding with this time point₂₁)…Len(t_2Q); P > 1, Q > 1, P ∈ N, Q ∈ N.

In a preferred embodiment of the invention, step S23 specifically includes:

S231. l is chosen₁₁、l₁₂、φ₁Arbitrary array in parameter array, by t₁₁…t_1PAnd this arbitrary array substitutes into formula 6, obtain P operation result; Calculate P operation result and Len (t respectively₁₁)…Len(t_1P) difference, obtain l₁₁、l₁₂、P difference of this arbitrary array in parameter array;

Further, l is chosen₂₁、l₂₂、Arbitrary array in parameter array, by t₂₁…t_2QAnd this arbitrary array substitutes into formula 7, obtain Q operation result; Calculate Q operation result and Len (t respectively₂₁)…Len(t_2Q) difference, obtain l₂₁、l₂₂、Q difference of this arbitrary array in parameter array.

S232. l is compared₁₁、l₁₂、The size of P difference of arbitrary array and first threshold in parameter array, adds up the difference quantities less than first threshold in P difference, and using this difference quantities as l₁₁、l₁₂、The passing number of this arbitrary array in parameter array; First threshold requires to arrange according to the first radar accuracy;

Further, l is compared₂₁、l₂₂、The size of Q difference of arbitrary array and Second Threshold in parameter array, adds up the difference quantities less than Second Threshold in Q difference, and using this difference quantities as l₂₁、l₂₂、The passing number of this arbitrary array in parameter array; Second Threshold requires to arrange according to the second radar accuracy.

S233. l is chosen₁₁、l₁₂、The array that in parameter array, passing number is maximum, using the parameter of this array parameter as the first radar target radical length curve;

Further, l is chosen₂₁、l₂₂、The array that in parameter array, passing number is maximum, using the parameter of this array parameter as the second radar target radical length curve.

Step S2 utilizes the method for curve matching, has been accurately determined the target radial length curve of the first radar and the second radar by Generalized Hough Transform (GHT).

In a preferred embodiment of the invention, obtain target radial length curve by the another kind of form of Generalized Hough Transform, step S23 particularly as follows:

S234. by l₁₁、l₁₂、Each array in parameter array arranges line by line, generates the l of a*3₁₁、l₁₂、Parameter matrix, builds the null matrix with this parameter matrix homotype as the first accumulated matrix simultaneously; l₁₁、l₁₂、Each parameter array in parameter matrix a line every with the first accumulated matrix is corresponding; A is l₁₁、l₁₂、The quantity of parameter array in parameter matrix;

Further, by l₂₁、l₂₂、Each array in parameter array arranges line by line, generates the l of b*3₂₁、l₂₂、Parameter matrix, builds the null matrix with this parameter matrix homotype as the second accumulated matrix simultaneously; l₂₁、l₂₂、Each parameter array in parameter matrix a line every with the second accumulated matrix is corresponding; B is l₂₁、l₂₂、The quantity of parameter array in parameter matrix.

S235. by any time point in the target radial length information of the first radar acquisition and l₁₁、l₁₂、Each parameter array in parameter matrix substitutes into formula 6, obtains a the operation result corresponding to each parameter array; Calculate the difference of above-mentioned a the operation result target radial length corresponding with this time point; Comparing what obtain corresponding to a difference of each parameter array and first threshold, labelling difference is less than the parameter array of first threshold, and adds 1 at the row of the first accumulated matrix corresponding to this parameter array;

Further, by any time point in the target radial length information of the second radar acquisition and l₂₁、l₂₂、Each parameter array in parameter matrix substitutes into formula 7, obtains b the operation result corresponding to each parameter array;Calculate the difference of above-mentioned b the operation result target radial length corresponding with this time point; Comparing what obtain corresponding to b difference of each parameter array and Second Threshold, labelling difference is less than the parameter array of Second Threshold, and adds 1 at the row of the second accumulated matrix corresponding to this parameter array.

S236. P time point in the target radial length information obtained by the first radar performs successively according to step S235; Choose maximum in the first accumulated matrix and be expert at the parameter array of correspondence as the parameter of the first radar target radical length curve;

Further, Q time point in the target radial length information obtained by the second radar performs successively according to step S235; Choose maximum in the second accumulated matrix and be expert at the parameter array of correspondence as the parameter of the second radar target radical length curve.

S3. utilizing the first radar target radical length curve and the second radar target radical length curve to calculate the precession axis angle of sight difference of target angle of precession and the first radar and the second radar, the described precession axis angle of sight is the angle of radar line of sight and target precession axis.

In a preferred embodiment of the invention, step S3 specifically includes:

S31. the first radar target radical length curve, the second radar target radical length curve and formula 1 is utilized to calculate target angle of precession.

$tg\mathrm{\θ}=\sqrt{\frac{Y_1^2-Y_2^2}{X_2^2-X_1^2}}$ Formula 1

Wherein, X₁It is that the first radar is at first time period T₁In, the sum of the maxima and minima of target radial length; Y₁It is that the first radar is at first time period T₁In, the difference of the maxima and minima of target radial length; X₂It is that the second radar is at the second time period T₂In, the sum of the maxima and minima of target radial length; Y₂It is that the second radar is at the second time period T₂In, the difference of the maxima and minima of target radial length.

S32. the first radar target radical length curve, the second radar target radical length curve, target angle of precession and formula 2 is utilized to calculate the precession axis angle of sight difference of the first radar and the second radar.

$tg({\mathrm{\β}}_i-{\mathrm{\α}}_i)=\frac{X_1{Y}_2-Y_1{X}_2}{\sin \mathrm{\θ}\cos \mathrm{\θ}\[\frac{X_1{X}_2}{{\cos }^2\mathrm{\θ}}+\frac{Y_1{Y}_2}{{\sin }^2\mathrm{\θ}}\]}$ Formula 2

Wherein, α_iIt is the precession axis angle of sight of the first radar, and α_iArrange from 0 ° to 90 ° according to the first step value; β_iFor with α_iThe precession axis angle of sight of the second corresponding radar; I > 1 and i ∈ N.

In a preferred embodiment of the invention, if the first step value is 5 °, then α_iIt it is 0 °, 5 °, 10 °, 15 °, 20 °, 25 ° ... 90 °; If the first step value is 10 °, then α_iIt it is 10 °, 20 °, 30 ° ... 90 °.

Formula 1, formula 2 derivation as follows:

Assuming in midcourse short time period T, the radar precession axis angle of sight is similar to constant, and by step S2, in time period T1, the first radar can obtain one group of radical length Len₁, at time period T₂Interior second radar can obtain one group of radical length Len₂Even if, T₁And T₂It is both less than a precession period, radical length curve can both be estimated, thus obtaining maximum and the minima of radical length in a cycle T. For the first radar, according to formula 12, it is known that maximum and the minima of radical length occur in:WithCorresponding radical length is respectively as follows:

Len(t₁)=Lcos (α-θ)-Rsin (α-θ)

Len(t₂)=Lcos (α+θ)-Rsin (α+θ)

Then at T₁Radical length maximum and minima in time period be:

max(Len₁)=Lcos (α-θ)-Rsin (α-θ)

min(Len₁)=Lcos (α+θ)-Rsin (α+θ)

Order:

X₁=max (Len₁)+min(Len₁)

Y₁=max (Len₁)-min(Len₁)

Can obtain:

X₁=2Lcos α cos θ-2Rcos θ sin α

Y₁=2Lsin α sin θ+2Rcos α sin θ formula 15

Thus:

$cos\mathrm{\α}=\frac{L\frac{X_1}{\cos \mathrm{\θ}}+R\frac{Y_1}{\sin \mathrm{\θ}}}{2(L^2+R^2)}$

$sin\mathrm{\α}=\frac{L\frac{Y}{\sin \mathrm{\θ}}-R\frac{X_1}{cos\mathrm{\θ}}}{2(L^2+R^2)}$

Due to cos²α+sin²α=1, can obtain:

$\frac{{Y_1}^2}{{\sin }^2\mathrm{\θ}}+\frac{{X_1}^2}{{\cos }^2\mathrm{\θ}}=4(L^2+R^2)$

In like manner, for the second radar:

$\frac{{Y_2}^2}{{\sin }^2\mathrm{\θ}}+\frac{{X_2}^2}{{\cos }^2\mathrm{\θ}}=4(L^2+R^2)$

Above-mentioned two formula simultaneous can be obtained:

$\frac{{Y_1}^2}{{\sin }^2\mathrm{\θ}}+\frac{{X_1}^2}{{\cos }^2\mathrm{\θ}}=\frac{{Y_2}^2}{{\sin }^2\mathrm{\θ}}+\frac{{X_2}^2}{{\cos }^2\mathrm{\θ}}$

Slightly do deformation can obtain:

$tg\mathrm{\θ}=\sqrt{\frac{Y_1^2-Y_2^2}{X_2^2-X_1^2}}$ Formula 1

Meanwhile, can obtain according to formula 15:

$L=\frac{\frac{Y_{1}sin\mathrm{\α}}{sin\mathrm{\θ}}+\frac{X_{1}cos\mathrm{\α}}{cos\mathrm{\θ}}}{2}$

$R=\frac{\frac{Y_{1}cos\mathrm{\α}}{\sin \mathrm{\θ}}-\frac{X_{1}sin\mathrm{\α}}{cos\mathrm{\θ}}}{2}$

In like manner, can obtain for the second radar:

$L=\frac{\frac{Y_{2}sin\mathrm{\β}}{sin\mathrm{\θ}}+\frac{X_{2}cos\mathrm{\β}}{cos\mathrm{\θ}}}{2}$

$R=\frac{\frac{Y_{2}cos\mathrm{\β}}{\sin \mathrm{\θ}}-\frac{X_{2}sin\mathrm{\β}}{cos\mathrm{\θ}}}{2}$

Above-mentioned two formula simultaneous can be obtained:

$tg(\mathrm{\β}-\mathrm{\α})=\frac{X_1{Y}_2-Y_1{X}_2}{sin\mathrm{\θ}cos\mathrm{\θ}\[\frac{X_1{X}_2}{{\cos }^2\mathrm{\θ}}+\frac{Y_1{Y}_2}{{\sin }^2\mathrm{\θ}}\]}$

In step s3, the first radar and the second radar, in shorter observation time, can accurately calculate target angle of precession and precession axis angle of sight difference, and on this basis, the present invention is capable of the short time extraction to object construction parameter;Compared with prior art, the observation time extracted needed for precession feature is greatly reduced. Meanwhile, by formula 1, present invention achieves with the degree of precision extraction to target angle of precession.

S4. based target angle of precession, precession axis angle of sight difference, the first radar target radical length curve and the second radar target radical length curve calculate target length and target bottom surface radius.

In a preferred embodiment of the invention, step S4 specifically includes:

S41. based target angle of precession, precession axis angle of sight difference and formula 3, formula 4 calculate corresponding to each the first radar precession axis angle of sight α_iTarget sample length L_iAnd target sample bottom surface radius R_i;

$\left[\begin{array}{c}Len\left(T_{11}\right)\\ ...\\ Len\left(T_{1N}\right)\\ Len\left(T_{21}\right)\\ ...\\ Len\left(T_{2M}\right)\end{array}\right]=A\left[\begin{array}{c}{L}_i\\ R_i\end{array}\right]$ Formula 3

Wherein,

Formula 4

Wherein, T₁₁…T_1NFor T₁Interior N number of time point, T₂₁…T_2MFor T₂M interior time point; M > 1, N > 1, M ∈ N, N ∈ N; Len (T₁₁)…Len(T_1N) be and T₁₁…T_1NCorresponding target radial length, Len (T₂₁)…Len(T_2M) be and T₂₁…T_2MCorresponding target radial length; ω is target angular velocity of precession;Respectively the first radar, target precession initial phase angle under the second radar visual angle; τ₁₁…τ_1NFor with T₁₁…T_1NThe first corresponding radar line of sight angle, τ₂₁…τ_2MFor with T₂₁…T_2MThe second corresponding radar line of sight angle; And

Formula 3, formula 4 are obtained by formula 12.

In a preferred embodiment of the invention, method of least square is utilized to try to achieve corresponding to each the first radar precession axis angle of sight α_iTarget sample length L_iAnd target sample bottom surface radius R_i。

S42. according to target sample length L_iAnd target sample bottom surface radius R_iExtract target length and target bottom surface radius.

In a preferred embodiment of the invention, step S42 specifically includes:

S421. each group of target sample length R is calculated according to formula 5_iAnd target sample bottom surface radius L_iError amount e (α_i);

$e\left({\mathrm{\α}}_i\right)=\left|\right|A\left[\begin{array}{c}{L}_i\\ R_i\end{array}\right]-\left[\begin{array}{c}Len\left(T_{11}\right)\\ ...\\ Len\left(T_{1N}\right)\\ Len\left(T_{21}\right)\\ ...\\ Len\left(T_{2M}\right)\end{array}\right]|{|}^2$ Formula 5

S422. compare the size of all error amounts, and extract target sample length corresponding to minimum error amount as target length, extract target sample bottom surface radius corresponding to minimum error amount as target bottom surface radius.

In step s 4, it is not necessary to understand precession target RCS characteristic under various attitudes or shape, namely higher precision can extract its structural parameters.

In a preferred embodiment of the invention, precession object construction parameter extracting method provided by the invention, before step S1, also include:

S0. appoint from U portion radar and take two and be combined into one group, form V group radar; Target length L is extracted according to two radars in described V group radar arbitrary group_jAnd target bottom surface radius R_j;

After step s4, also include:

S5. according to target length L_jAnd target bottom surface radius R_jCalculate optimum target length and optimum target bottom surface radius; Wherein, U > 2, and U ∈ N;1≤j≤V, and j ∈ N.

In a preferred embodiment of the invention, step S5 particularly as follows:

L is calculated according to formula 8_jMeansigma methods L^#, by L_jMeansigma methods L^#As optimum target length;

R is calculated according to formula 9_jMeansigma methods R^#, by R_jMeansigma methods R^#As optimum target bottom surface radius;

$L^{\#}=\frac{\underset{j=1}{\overset{V}{\Σ}}{L}_j}{V}$ Formula 8

$R^{\#}=\frac{\underset{j=1}{\overset{V}{\Σ}}{R}_j}{V}$ Formula 9.

In a preferred embodiment of the invention, step S5 particularly as follows:

L is calculated according to formula 10_jWeighted mean L^*, by L_jWeighted mean L^*As optimum target length;

R is calculated according to formula 11_jWeighted mean R^*, by R_jWeighted mean R^*As optimum target bottom surface radius;

$L*=\frac{\underset{j=1}{\overset{V}{\Σ}}{W}_j{L}_j}{\underset{j=1}{\overset{V}{\Σ}}{W}_j}$ Formula 10

$R*=\frac{\underset{j=1}{\overset{V}{\Σ}}{W}_j{R}_j}{\underset{j=1}{\overset{V}{\Σ}}{W}_j}$ Formula 11

Wherein, W_jFor the weights of jth group, W in V group radar_jPerformance parameter according to each radar in two radars in jth group such as certainty of measurement, detection range, stability parameter, dependability parameter etc. are determined.

In a preferred embodiment of the invention, based on each group of target angle of precession obtained in V group radar, meansigma methods or the weighted mean of above-mentioned target angle of precession are calculated, as optimum target angle of precession.

Hereby it is achieved that extracted the technique effect of object construction parameter and target angle of precession by the radar more than two, further increase object construction parameter and the extraction accuracy of target angle of precession.

Fig. 3 is the second flow chart of the precession object construction parameter extracting method of the present invention; Wherein, initially set up precession object module, afterwards,

First radar utilizes for 1 time optimal path method to obtain target radial length information from target one-dimensional range profile at visual angle, and obtains its target radial length curve by GHT (Generalized Hough Transform).

Second radar utilizes for 2 times optimal path method to obtain target radial length information from target one-dimensional range profile at visual angle, and obtains its target radial length curve by GHT (Generalized Hough Transform).

Finally, obtain target angle of precession and precession axis angle of sight difference through the derivation of equation and step S3, S4, finally give target length, target bottom surface radius.

Precession object construction parameter extracting method based on many radars provided by the invention, it is possible to accurately extract structural parameters and the angle of precession of cooperation/noncooperative target with less error, significantly reduces the observation time extracted needed for precession feature simultaneously.

One of ordinary skill in the art will appreciate that all or part of step realizing in above-described embodiment method can be by the hardware that program carrys out instruction relevant and completes, this program can be stored in a computer read/write memory medium, as: ROM/RAM, magnetic disc, CD etc.

The above is only the preferred embodiment of the present invention; it should be pointed out that, for those skilled in the art, under the premise without departing from the principles of the invention; can also making some improvements and modifications, these improvements and modifications also should be regarded as protection scope of the present invention.

Claims (10)

1. a precession object construction parameter extracting method, it is characterised in that including:

S1. the first radar target radical length information is obtained by the target one-dimensional range profile of the first radar; The second radar target radical length information is obtained by the target one-dimensional range profile of the second radar;

S2. the first radar target radical length curve is calculated according to the first radar target radical length information; The second radar target radical length curve is calculated according to the second radar target radical length information;

S3. the first radar target radical length curve and the second radar target radical length curve is utilized to calculate the precession axis angle of sight difference of target angle of precession and the first radar and the second radar;

S4. based target angle of precession, precession axis angle of sight difference, the first radar target radical length curve and the second radar target radical length curve calculate target length and target bottom surface radius;

The described precession axis angle of sight is the angle of radar line of sight and target precession axis.

2. the method for claim 1, it is characterised in that step S3 specifically includes:

S31. the first radar target radical length curve, the second radar target radical length curve and formula 1 is utilized to calculate target angle of precession;

$tg\mathrm{\θ}=\sqrt{\frac{Y_1^2-Y_2^2}{X_2^2-X_1^2}}$ Formula 1

S32. the first radar target radical length curve, the second radar target radical length curve, target angle of precession and formula 2 is utilized to calculate the precession axis angle of sight difference of the first radar and the second radar;

$tg({\mathrm{\β}}_i-{\mathrm{\α}}_i)=\frac{X_1{Y}_2-Y_1{X}_2}{sin\mathrm{\θ}cos\mathrm{\θ}\[\frac{X_1{X}_2}{{\cos }^2\mathrm{\θ}}+\frac{Y_1{Y}_2}{{\sin }^2\mathrm{\θ}}\]}$ Formula 2

Wherein, θ is target angle of precession; X₁It is that the first radar is at first time period T₁In, the sum of the maxima and minima of target radial length; Y₁It is that the first radar is at first time period T₁In, the difference of the maxima and minima of target radial length; X₂It is that the second radar is at the second time period T₂In, the sum of the maxima and minima of target radial length;Y₂It is that the second radar is at the second time period T₂In, the difference of the maxima and minima of target radial length; α_iIt is the precession axis angle of sight of the first radar, and α_iArrange from 0 ° to 90 ° according to the first step value; β_iFor with α_iThe precession axis angle of sight of the second corresponding radar; I > 1 and i ∈ N.

3. method as claimed in claim 2, it is characterised in that step S4 specifically includes:

S41. based target angle of precession, precession axis angle of sight difference and formula 3, formula 4 calculate corresponding to each first radar precession axis angle of sight α_iTarget sample length L_iAnd target sample bottom surface radius R_i;

$\left[\begin{array}{c}Len\left(T_{11}\right)\\ ...\\ Len\left(T_{1N}\right)\\ Len\left(T_{21}\right)\\ ...\\ Len\left(T_{2M}\right)\end{array}\right]=A\left[\begin{array}{c}{L}_i\\ R_i\end{array}\right]$ Formula 3

Wherein

Formula 4

S42. according to target sample length L_iAnd target sample bottom surface radius R_iExtract target length and target bottom surface radius;

Wherein, T₁₁…T_1NFor T₁Interior N number of time point, T₂₁…T_2MFor T₂M interior time point; M > 1, N > 1, M ∈ N, N ∈ N; Len (T₁₁)…Len(T_1N) be and T₁₁…T_1NCorresponding target radial length, Len (T₂₁)…Len(T_2M) be and T₂₁…T_2MCorresponding target radial length; ω is target angular velocity of precession;Respectively the first radar, target precession initial phase angle under the second radar visual angle; τ₁₁…τ_1NFor with T₁₁…T_1NThe first corresponding radar line of sight angle, τ₂₁…τ_2MFor with T₂₁…T_2MThe second corresponding radar line of sight angle; And

…

…

4. method as claimed in claim 3, it is characterised in that step S42 specifically includes:

S421. each group of target sample length R is calculated according to formula 5_iAnd target sample bottom surface radius L_iError amount e (α_i);

$e\left({\mathrm{\α}}_i\right)=\left|\right|A\left[\begin{array}{c}{L}_i\\ R_i\end{array}\right]-\left[\begin{array}{c}Len\left(T_{11}\right)\\ ...\\ Len\left(T_{1N}\right)\\ Len\left(T_{21}\right)\\ ...\\ Len\left(T_{2M}\right)\end{array}\right]|{|}^2$ Formula 5

S422. compare the size of all error amounts, and extract target sample length corresponding to minimum error amount as target length, extract target sample bottom surface radius corresponding to minimum error amount as target bottom surface radius.

5. method as claimed in claim 4, it is characterised in that step S2 specifically includes:

S21. according to the first radar target radical length information, it is determined that the parameter l of the first radar target radical length curve₁₁、l₁₂、Span; According to the second radar target radical length information, it is determined that the parameter l of the second radar target radical length curve₂₁、l₂₂、Span;

S22. based on l₁₁、l₁₂、Span and required precision, arrange respectively with l₁₁、l₁₂、Corresponding value interval, to l₁₁、l₁₂、Carry out discrete value, generate l₁₁、l₁₂、Parameter array; And

Based on l₂₁、l₂₂、Span and required precision, arrange respectively with l₂₁、l₂₂、Corresponding value interval, to l₂₁、l₂₂、Carry out discrete value, generate l₂₁、l₂₂、Parameter array;

S23. the target radial length information and the formula 6 that utilize the first radar acquisition check l₁₁、l₁₂、Parameter array; The parameter of the first radar target radical length curve is determined according to testing result; And

The target radial length information and the formula 7 that utilize the second radar acquisition check l₂₁、l₂₂、Parameter array; The parameter of the second radar target radical length curve is determined according to testing result;

Formula 6

Formula 7

The target radial length information that described first radar obtains includes time point t₁₁…t_1PAnd the target radial length Len (t corresponding with this time point₁₁)…Len(t_1P);

The target radial length information that described second radar obtains includes time point t₂₁…t_2QAnd the target radial length Len (t corresponding with this time point₂₁)…Len(t_2Q); P > 1, Q > 1, P ∈ N, Q ∈ N.

6. method as claimed in claim 5, it is characterised in that step S23 specifically includes:

S231. l is chosen₁₁、l₁₂、Arbitrary array in parameter array, by t₁₁…t_1PAnd this arbitrary array substitutes into formula 6, obtain P operation result; Calculate P operation result and Len (t respectively₁₁)…Len(t_1P) difference, obtain l₁₁、l₁₂、P difference of this arbitrary array in parameter array;And

Choose l₂₁、l₂₂、Arbitrary array in parameter array, by t₂₁…t_2QAnd this arbitrary array substitutes into formula 7, obtain Q operation result; Calculate Q operation result and Len (t respectively₂₁)…Len(t_2Q) difference, obtain l₂₁、l₂₂、Q difference of this arbitrary array in parameter array;

S232. l is compared₁₁、l₁₂、The size of P difference of arbitrary array and first threshold in parameter array, adds up the difference quantities less than first threshold in P difference, and using this difference quantities as l₁₁、l₁₂、The passing number of this arbitrary array in parameter array; And

Relatively l₂₁、l₂₂、The size of Q difference of arbitrary array and Second Threshold in parameter array, adds up the difference quantities less than Second Threshold in Q difference, and using this difference quantities as l₂₁、l₂₂、The passing number of this arbitrary array in parameter array;

S233. l is chosen₁₁、l₁₂、The array that in parameter array, passing number is maximum, using the parameter of this array parameter as the first radar target radical length curve; And

Choose l₂₁、l₂₂、The array that in parameter array, passing number is maximum, using the parameter of this array parameter as the second radar target radical length curve;

Described first threshold requires to arrange according to the first radar accuracy;

Described Second Threshold requires to arrange according to the second radar accuracy.

7. the method as described in as arbitrary in claim 1-6, it is characterised in that step S1 particularly as follows:

By the target one-dimensional range profile of the first radar, optimal path method is utilized to obtain the first radar target radical length information; By the target one-dimensional range profile of the second radar, optimal path method is utilized to obtain the second radar target radical length information.

8. method as claimed in claim 7, it is characterised in that before step S1, described method also includes:

S0. appoint from U portion radar and take two and be combined into one group, form V group radar; Target length L is extracted according to two radars in described V group radar arbitrary group_jAnd target bottom surface radius R_j;

After step s4, described method also includes:

S5. according to target length L_jAnd target bottom surface radius R_jCalculate optimum target length and optimum target bottom surface radius; Wherein, U > 2, and U ∈ N;1≤j≤V, and j ∈ N.

9. method as claimed in claim 8, it is characterised in that step S5 particularly as follows:

L is calculated according to formula 8_jMeansigma methods L^#, by L_jMeansigma methods L^#As optimum target length;

R is calculated according to formula 9_jMeansigma methods R^#, by R_jMeansigma methods R^#As optimum target bottom surface radius;

$L^{\#}=\frac{\underset{j=1}{\overset{V}{\Σ}}{L}_j}{V}$ Formula 8

$R^{\#}=\frac{\underset{j=1}{\overset{V}{\Σ}}{R}_j}{V}$ Formula 9.

10. method as claimed in claim 8, it is characterised in that step S5 particularly as follows:

L is calculated according to formula 10_jWeighted mean L^*, by L_jWeighted mean L^*As optimum target length;

R is calculated according to formula 11_jWeighted mean R^*, by R_jWeighted mean R^*As optimum target bottom surface radius;

$L*=\frac{\underset{j=1}{\overset{V}{\Σ}}{W}_j{L}_j}{\underset{j=1}{\overset{V}{\Σ}}{W}_j}$ Formula 10

$R*=\frac{\underset{j=1}{\overset{V}{\Σ}}{W}_j{R}_j}{\underset{j=1}{\overset{V}{\Σ}}{W}_j}$ Formula 11

Wherein, W_jFor the weights of jth group radar, W in V group radar_jDetermined by the performance parameter of each radar in two radars in jth group.