CN109754004A - A kind of antithesis G4U goal decomposition method of polarimetric SAR image - Google Patents

Abstract

A kind of antithesis G4U goal decomposition method of polarimetric SAR image, the described method includes: polarimetric SAR image to be decomposed based on the equilibrium equation that G4U is abandoned, is obtained an antithesis G4U and is decomposed, the effective supplement decomposed to original G4U is obtained, realization obtains goal decomposition to polarimetric SAR image.The equilibrium equation that goal decomposition method of the invention is abandoned by G4U obtains a completely new antithesis G4U and decomposes, realizes effective supplement to original G4U decomposability, so that the identification and understanding to radar target are more accurate.

Description

A kind of antithesis G4U goal decomposition method of polarimetric SAR image

Technical field

The present invention relates to polarimetric SAR image field of information processing, in particular to polarization SAR goal decomposition and based on model A kind of goal decomposition field, and in particular to antithesis G4U goal decomposition method of polarimetric SAR image.

Background technique

Polarization decomposing based on model is dedicated to the polarization coherence matrix [T] by unknown object in several standard scattering models Upper expansion, realization identify and classify to it.It is Freeman-Durden (A.Freeman and that it, which represents work, S.L.Durden,“A three-component scattering model for polarimetric SAR data,” IEEE Transactions on Geoscience and Remote Sensing,vol.36,no.3,pp.963-973,May 1998) three-component model proposed decomposes and (Y.Yamaguchi, T.Moriyama, M.Ishido, the and such as Yamaguchi H.Yamada,“Four-component scattering model for polarimetric SAR image decomposition,”IEEE Transactions on Geoscience and Remote Sensing,vol.43, No.8, pp.1699-1706, Aug.2005.) propose four component Models decompose (being abbreviated as Y4O).Y4O is by target coherence matrix [T] is decomposed into the combination of surface scattering, two area scatterings, volume scattering and spiral scattering, realize to coherence matrix [T] six from By the explanation spent, but still there are three freedom degrees to be not used, and corresponds respectively to T₁₃Component and T₂₃The real part of component.In order to realize To T₂₃The use of component real part, (Y.Yamaguchi, A.Sato, W.-M.Boerner, R.Sato, the and such as Yamaguchi H.Yamada,“Four-component scattering power decomposition with rotation of coherency matrix,”IEEE Transactions on Geoscience and Remote Sensing,vol.49, No.6, pp.2251-2258, Jun.2011) Y4R decomposition is developed on the basis of Y4O, by introducing rotation unitary transformation, benefit Orientation operation is spent by T₂₃Component real part zero setting realizes the explanation to coherence matrix [T] 7 degree of freedom.On the basis of Y4R On, (A.Sato, Y.Yamaguchi, G.Singh, the and S.-E.Park, " Four-component scattering such as Sato power decomposition with extended volume scattering model,”IEEE Geoscience And Remote Sensing Letters, vol.9, no.2, pp.166-170, Mar.2012) further develop S4R points Solution, but as Y4R, T₁₃Component can not still be utilized effectively in S4R.In order to reach this purpose, Singh etc. (G.Singh,Y.Yamaguchi,and S.-E.Park,“General four-component scattering power decomposition with unitary transformation of coherency matrix,”IEEE Transactions on Geoscience and Remote Sensing,vol.51,no.5,pp.3014-3022,May 2013) G4U decomposition was proposed in 2013, was realized by introducing another unitary transformation to T₁₃The partial interpretation of component, generation Table four components decompose state-of-the-art.

The core of model decomposition is to solve for dissociation equation group, and traditional Y4O, Y4R and S4R are provided about unknown parameter Five equations, but the T of coherence matrix [T] is all not directed in these equations₁₃Component, therefore cannot achieve to T₁₃Effectively make With.G4U passes through one: the f in five equilibrium equations that unitary transformation mathematically forms Y4O, Y4R and S4R_Sβ+f_Dα+f_VD= T′₁₂Two points are f_Sβ+f_Dα+f_VD=T '₁₂+T′₁₃And f_Sβ+f_Dα+f_VD=T '₁₂-T′₁₃Two equations, successfully by T₁₃Component is received Enter in equation right end, to make T₁₃Component for the first time four components decomposition in obtain using.However due to the two equation sources It is not completely independent in two points of the same equation, therefore between them, finally obtained equilibrium equation group is caused no longer to have There is unique accurate solution.Singh etc. has only selected Equation f in G4U thus_Sβ+f_Dα+f_VD=T '₁₂+T′₁₃, and abandon Equation f_S β+f_Dα+f_vD=T '₁₂-T′₁₃.This operation, which is intended merely to obtain one group, effectively to be solved, not due to Equation f_Sβ+f_Dα+f_VD=T ′₁₂-T′₁₃Existing defects.It is one that this abort operation, which makes the originally existing diversity understanding to target scattering mechanism degenerate, The G4U decomposed form of a fixation, to accurately identify and understand the potential adverse effect of generation to radar target.

Summary of the invention

It is an object of the invention to overcome above-mentioned technological deficiency, based on the equilibrium equation that G4U is abandoned, obtain one it is completely new Antithesis G4U is decomposed, and realizes the effective supplement decomposed to original G4U.

To achieve the goals above, the present invention provides a kind of antithesis G4U goal decomposition method of polarimetric SAR image, institutes The method of stating includes: that polarimetric SAR image to be decomposed based on the equilibrium equation that G4U is abandoned, is obtained an antithesis G4U and decomposed, obtained The effective supplement decomposed to original G4U is obtained, realization obtains goal decomposition to polarimetric SAR image.

As a kind of improvement of the above method, the method is specifically included:

Step 1) reads in the coherence matrix [T] of polarimetric SAR image to be decomposed, carries out orientation operation and obtains the phase for going orientation Dry matrix [T ']；

Step 2) is based on the coherence matrix [T '] for going orientation that step 1) obtains, and calculates spiral scattered power P_CAnd branch Conditional parameter BC₀、BC₁And BC₂, it is based on BC₁And BC₂It determines volume scattering model parameter a, b, c and d and calculates volume scattering power P_V, According to P_VSymbol to P_C、BC₀、BC₁、BC₂, a, b, c and d etc. be updated, obtain the P for meeting non-negative physical criteria_V；

Step 3) is based on the obtained coherence matrix [T '] of step 1) and volume scattering model parameter a, b, c of step 2) determination And d, resolution parameter S and D are further calculated, according to the semiology analysis power conservation criterion of S+D, if not just, then no longer computational chart Area scattering power P_SWith two area scattering power Ps_D, directly update volume scattering power P_V；Otherwise, it is transferred to step 4)；

Step 4) is based on the resolution parameter S and D that step 3) obtains, if S+D is positive, is based on the relevant square that step 1) obtains Volume scattering model parameter a, b, c and d that battle array [T '] and step 2) determine further calculate resolution parameter C, combine resolution parameter S With D gauging surface scattered power P_SWith two area scattering power Ps_D, according to P_SAnd P_DSymbol to P_SAnd P_DIt updates again, acquisition meets non- The P of negative physical criteria_SAnd P_D。

As a kind of improvement of the above method, in step 1), if the coherence matrix [T] of polarimetric SAR image to be decomposed are as follows:

Coherence matrix [T '] after then going orientation are as follows:

Wherein [U₃(θ)] indicate SU (3) spin matrix:

The estimation mode of angle of orientation θ is as follows:

As the further improvement of the above method, the step 2) further comprises:

Step 2-1) calculate spiral scattered power P_C:

P_C=2 | Im { T '₂₃}|

Step 2-2) it is based on P_CCalculate branch condition parameter BC₀、BC₁And BC₂:

Step 2-3) it is based on BC₁And BC₂Determine volume scattering model parameter a, b, c and d:

Step 2-4) calculate volume scattering power P_V:

Step 2-5) according to P_VSymbol is to P_C、BC₀、BC₁、BC₂, a, b, c and d etc. be updated: if P_V< 0, then it sets

P_C=0

Return step 2-2), otherwise, it is transferred to step 3).

As the further improvement of the above method, the step 3) further comprises:

Step 3-1) calculate resolution parameter S and D:

Step 3-2) it is set according to S+D semiology analysis power conservation criterion if S+D≤0

P_S=0, P_D=0

Update P_V

P_V=SPAN-P_C

Wherein, SPAN is target total scattering power:

SPAN=T '₁₁+T′₂₂+T′₃₃。

As the further improvement of the above method, the step 4) further comprises:

Step 4-1) if S+D >=0, calculate resolution parameter C:

C=T '₁₂-T′₁₃-P_Vd

Step 4-2) gauging surface scattered power P_SWith two area scattering power Ps_D:

Step 4-3) according to P_SAnd P_DSymbol to P_SAnd P_DCarry out non-negative update:

The present invention has the advantages that

The equilibrium equation that goal decomposition method of the invention is abandoned by G4U obtains a completely new antithesis G4U and decomposes, Effective supplement to original G4U decomposability is realized, so that the identification and understanding to radar target are more accurate.

Detailed description of the invention

Fig. 1 is the overview flow chart of the antithesis G4U goal decomposition method of polarimetric SAR image of the invention；

Fig. 2 is the specific flow chart of the antithesis G4U goal decomposition method of polarimetric SAR image of the invention；

Fig. 3 is polarimetric SAR image coherence matrix [T] data to be decomposed employed in one embodiment of the present of invention Pauli figure；

Fig. 4 is that the spiral that polarimetric SAR image obtains after method of the invention is decomposed in the embodiment of the present invention scatters function Rate P_CLogarithmetics show (i.e. log₁₀P_C)；

Fig. 5 is the volume scattering power that polarimetric SAR image obtains after method of the invention is decomposed in the embodiment of the present invention P_VLogarithmetics show (i.e. log₁₀P_V)；

Fig. 6 is the surface scattering function that polarimetric SAR image obtains after method of the invention is decomposed in the embodiment of the present invention Rate P_SLogarithmetics show (i.e. log₁₀P_S)；

Fig. 7 is the two area scattering function that polarimetric SAR image obtains after method of the invention is decomposed in the embodiment of the present invention Rate P_DLogarithmetics show (i.e. log₁₀P_D)；

Fig. 8 is the final result that polarimetric SAR image obtains after method of the invention is decomposed in the embodiment of the present invention.

Specific embodiment

Now in conjunction with attached drawing, the invention will be further described.

Research work shows Equation f_Sβ+f_Dα+f_VD=T '₁₂-T′₁₃One reasonable decomposition can be also provided, it is proper with G4U Dual form is constituted well, therefore referred to as antithesis G4U is decomposed.Antithesis G4U can overcome the disadvantages that G4U is existing and decomposes defect, provide pair The perfect supplement of one of G4U.

That is, Equation f_Sβ+f_Dα+f_VD=T '₁₂-T′₁₃Not only without defect, moreover it is possible to further provide for us one group Effectively solution constitutes dual form with G4U just, therefore referred to as antithesis G4U is decomposed.Antithesis G4U can overcome the disadvantages that G4U is existing and decompose Defect provides a perfect supplement to G4U, so that the identification and understanding to radar target are more accurate.

With reference to Fig. 1 and Fig. 2, a kind of antithesis G4U goal decomposition method of polarimetric SAR image of the invention, including following step It is rapid:

Step 1) reads in polarimetric SAR image coherence matrix [T] data to be decomposed, carries out orientation operation and obtains [T ']；

Step 2), the coherence matrix [T '] obtained based on step 1), calculate spiral scattered power P_CAnd branch condition ginseng Number BC₀、BC₁And BC₂, it is based on BC₁And BC₂It determines volume scattering model parameter a, b, c and d and calculates volume scattering power P_V, according to P_V Symbol to P_C、BC₀、BC₁、BC₂, a, b, c and d etc. be updated, obtain the P for meeting non-negative physical criteria_V；

Volume scattering model parameter a, b that step 3), the coherence matrix [T '] obtained based on step 1) and step 2) are determined, C and d further calculates resolution parameter S and D, according to the semiology analysis power conservation criterion of S+D, if not just, then no longer computational chart Area scattering power P_SWith two area scattering power Ps_D, directly update volume scattering power P_V；

Step 4), the resolution parameter S and D obtained based on step 3) are obtained relevant if S+D is positive based on step 1) Volume scattering model parameter a, b, c and d that matrix [T '] and step 2) determine further calculate resolution parameter C, and joint decomposes ginseng Number S and D gauging surface scattered power P_SWith two area scattering power Ps_D, according to P_SAnd P_DSymbol to P_SAnd P_DIt updates, is expired again The P of the non-negative physical criteria of foot_SAnd P_D。

The step in the method for the present invention is described further below.

In step 1), polarimetric SAR image coherence matrix [T] data to be decomposed are read in, orientation operation is carried out and obtains [T′]；In one embodiment, the Pauli for polarimetric SAR image coherence matrix [T] data to be decomposed read in schemes such as Fig. 3 institute Show, picture size 920 × 456, by Canadian C-band Radarsat-2 radar acquisition on April 9th, 2008 san francisco, usa Area.If the target coherence matrix [T] read in is

Target coherence matrix [T '] after going orientation calculates as follows:

Wherein [U₃(θ)] indicate SU (3) spin matrix:

The estimation mode of angle of orientation θ is as follows:

Based on the coherence matrix [T '] that step 1) obtains, in step 2), further execute as follows:

Step 2-1), calculate spiral scattered power P_C:

P_C=2 | Im { T '₂₃}|

Step 2-2), be based on P_CCalculate branch condition parameter BC₀、BC₁And BC₂:

Step 2-3), be based on BC₁And BC₂Determine volume scattering model parameter a, b, c and d:

Step 2-4), calculate volume scattering power P_V:

Step 2-5), according to P_VSymbol is to P_C、BC₀、BC₁、BC₂, a, b, c and d etc. be updated: if P_V< 0, then it sets

P_C=0

Return step 2-2), 2-3) and 2-4) undated parameter BC₀、BC₁、BC₂, a, b, c and d be otherwise transferred to step 3)；

Fig. 4 is shown in polarization SAR data in embodiment, the obtained logarithmic form P of the method for the present invention_C(i.e. log₁₀P_C, take log operations to be intended merely to reduce dynamic range here, decomposition result made to facilitate displaying).

Volume scattering model parameter a, b, c and d that the coherence matrix [T '] and step 2) obtained based on step 1) is determined, In step 3), further execute as follows:

Step 3-1), calculate resolution parameter S and D:

Step 3-2), set if S+D≤0 according to S+D semiology analysis power conservation criterion

P_S=0, P_D=0

Update P_V

P_V=SPAN-P_C

Wherein, SPAN is target total scattering power:

SPAN=T '₁₁+T′₂₂+T′₃₃

Fig. 5 is shown in polarization SAR data in embodiment, the obtained logarithmic form P of the method for the present invention_V, i.e., log₁₀P_V。

Based on resolution parameter S and D that step 3) obtains, if S+D is positive, it is based on the coherence matrix [T '] that step 1) obtains And volume scattering model parameter a, b, c and d that step 2) determines, in step 4), we further execute as follows:

Step 4-1) if, S+D >=0, calculate resolution parameter C:

C=T '₁₂-T′₁₃-P_vd

Step 4-2), gauging surface scattered power P_SWith two area scattering power Ps_D:

Step 4-3), according to P_SAnd P_DSymbol to P_SAnd P_DCarry out non-negative update:

Fig. 6 and Fig. 7 is shown in polarization SAR data in embodiment, the obtained logarithmic form P of the method for the present invention_S And P_D, i.e. log₁₀P_SAnd log₁₀P_D.Fig. 8 show in the polarization SAR data of the method for the present invention in embodiment obtain it is final Decomposition result figure.

It should be noted last that the above examples are only used to illustrate the technical scheme of the present invention and are not limiting.Although ginseng It is described the invention in detail according to embodiment, those skilled in the art should understand that, to technical side of the invention Case is modified or replaced equivalently, and without departure from the spirit and scope of technical solution of the present invention, should all be covered in the present invention Scope of the claims in.

Claims (6)

1. a kind of antithesis G4U goal decomposition method of polarimetric SAR image, which comprises for polarization SAR figure to be decomposed Picture is obtained an antithesis G4U and decomposed, obtain the effective supplement decomposed to original G4U, realized based on the equilibrium equation that G4U is abandoned Goal decomposition is obtained to polarimetric SAR image.

2. the antithesis G4U goal decomposition method of polarimetric SAR image according to claim 1, which is characterized in that the method It specifically includes:

Step 1) reads in the coherence matrix [T] of polarimetric SAR image to be decomposed, carries out orientation operation and obtains the relevant square for going orientation Battle array [T ']；

Step 2) is based on the coherence matrix [T '] for going orientation that step 1) obtains, and calculates spiral scattered power P_CAnd branch condition Parameter BC₀、BC₁And BC₂, it is based on BC₁And BC₂It determines volume scattering model parameter a, b, c and d and calculates volume scattering power R_V, according to R_VSymbol to P_C、BC₀、BC₁、BC₂, a, b, c and d etc. be updated, obtain the P for meeting non-negative physical criteria_V；

Volume scattering model parameter a, b, c and d that the coherence matrix [T '] and step 2) that step 3) is obtained based on step 1) determine, Resolution parameter S and D are further calculated, according to the semiology analysis power conservation criterion of S+D, if not just, then no longer gauging surface dissipates Penetrate power P_SWith two area scattering power Ps_D, directly update volume scattering power R_V；Otherwise, it is transferred to step 4)；

Step 4) is based on the resolution parameter S and D that step 3) obtains, if S+D is positive, is based on the coherence matrix that step 1) obtains Volume scattering model parameter a, b, c and d that [T '] and step 2) determine further calculate resolution parameter C, joint resolution parameter S and D gauging surface scattered power P_SWith two area scattering power Ps_D, according to P_SAnd P_DSymbol to P_SAnd P_DIt updates again, acquisition meets non-negative The P of physical criteria_SAnd P_D。

3. the antithesis G4U goal decomposition method of polarimetric SAR image according to claim 2, which is characterized in that the step 1) specifically:

If the coherence matrix [T] of polarimetric SAR image to be decomposed are as follows:

Coherence matrix [T '] after then going orientation are as follows:

Wherein [U₃(θ)] indicate SU (3) spin matrix:

The estimation mode of angle of orientation θ is as follows:

4. the antithesis G4U goal decomposition method of polarimetric SAR image according to claim 3, which is characterized in that the step 2) further comprise:

Step 2-1) calculate spiral scattered power P_C:

P_C=2 | Im { T '₂₃}|

Step 2-2) it is based on P_CCalculate branch condition parameter BC₀、BC₁And BC₂:

Step 2-3) it is based on BC₁And BC₂Determine volume scattering model parameter a, b, c and d:

Step 2-4) calculate volume scattering power P_V:

Step 2-5) according to R_VSymbol is to P_C、BC₀、BC₁、BC₂, a, b, c and d etc. be updated: if R_V< 0, then set

P_C=0

Return step 2-2), otherwise, it is transferred to step 3).

5. the antithesis G4U goal decomposition method of polarimetric SAR image according to claim 4, which is characterized in that the step 3) further comprise:

Step 3-1) calculate resolution parameter S and D:

Step 3-2) it is set according to S+D semiology analysis power conservation criterion if S+D≤0

P_S=0, P_D=0

Update P_V

R_V=SPAN-P_C

Wherein, SPAN is target total scattering power:

SPAN=T '₁₁+T′₂₂+T′₃₃。

6. the antithesis G4U goal decomposition method of polarimetric SAR image according to claim 5, which is characterized in that the step 4) further comprise:

Step 4-1) if S+D >=0, calculate resolution parameter C:

C=T '₁₂-T′₁₃-R_Vd

Step 4-2) gauging surface scattered power P_SWith two area scattering power Ps_D:

Step 4-3) according to P_SAnd P_DSymbol to P_SAnd P_DCarry out non-negative update: