CN103576151B - Azimuth multi-channel SAR imaging method and system based on compressed sensing - Google Patents

Abstract

The invention discloses an azimuth multi-channel SAR imaging method and system based on compressed sensing. The azimuth multi-channel SAR imaging method based on compressed sensing comprises the steps that (1) two-dimensional random sparse sampling is carried out on signals received by channels of the azimuth multi-channel SAR imaging system, (2) phase compensation is carried out sparse sampling data of the channels according to the relative position relation between receiving antennas of the channels and a central transmitting antenna, (3) range reconstruction imaging is carried out on range data, processed through phase compensation, of each orientation unit in the corresponding azimuth channel through compressed sensing, and (4) DPCA processing is carried out the data, processed through range reconstruction imaging, of each azimuth channel, and azimuth recovery processing is carried out on azimuth data in each range gate to carry out two-dimensional compressed sensing SAR imaging. According to the technical scheme, the data volume of the azimuth multi-channel SAR imaging system is greatly reduced, the PRF of the azimuth multi-channel SAR imaging system is not limited, and accurate imaging can be carried out on observation scenes.

Description

Based on the orientation of compressed sensing to hyperchannel SAR formation method and system

Technical field

The present invention relates to orientation to Multichannel SAR (SAR, Synthetic Aperture Radar) imaging technique, particularly relate to a kind of orientation based on compressed sensing to hyperchannel SAR formation method and system.

Background technology

Orientation is one of main stream approach realizing high resolving power and Wide swath SAR imaging at present to hyperchannel SAR imaging technique, this technology can reduce orientation to transponder pulse repetition frequency (PRF, Pulse RepetitionFrequency), further, covering wide survey can with while realize orientation to high-resolution imaging.Orientation has important application to hyperchannel SAR imaging technique in resources observation, marine charting, battle reconnaissance and environmental protection.

At present, single transmission antennas transmit signal in the middle of orientation utilizes to hyperchannel SAR system, orientation receives the echoed signal from target area respectively to multiple sub antenna, which results in orientation sharply to increase to the data volume of hyperchannel SAR system, bring serious burden to orientation to the storage of hyperchannel SAR system and data transmission link.Simultaneously, because antenna sub-aperture number, sub-aperture spacing and the orientation PRF to hyperchannel SAR system will strictly meet some requirements, when orientation does not meet this conditional request to the parameter of hyperchannel SAR system, orientation is non-uniformly sampled signals to the signal that hyperchannel SAR system receives, if directly utilize traditional single-channel SAR imaging algorithm to carry out imaging processing to non-uniformly sampled signals, imaging results there will be false target, produces serious orientation to fuzzy.

The algorithm separating orientation doppler ambiguity mainly contains wave filter restructing algorithm, but wave filter restructing algorithm is owing to relating to matrix inversion operation, when orientation is operated in some particular value to the PRF of hyperchannel SAR system, algorithm there will be reconstruct mismatch, cause follow-up imaging effect not good, effectively cannot eliminate the problems such as false target is fuzzy introduced due to nonuniform sampling.

Summary of the invention

In view of this, fundamental purpose of the present invention is to provide a kind of orientation based on compressed sensing to hyperchannel SAR formation method and system, greatly can reduce the data volume of orientation to hyperchannel SAR system, simultaneously, accurate imaging without the need to being restricted, also can be carried out to observation scene to the PRF of hyperchannel SAR system in orientation.

For achieving the above object, technical scheme of the present invention is achieved in that

Based on the orientation of compressed sensing to a hyperchannel SAR formation method, be applied to orientation to hyperchannel SAR system, described method comprises:

To orientation to each channel reception in hyperchannel SAR system to signal carry out two-dimensional random sparse sampling respectively;

According to the receiving antenna of each passage described and the relative position relation of central radiator, respectively phase compensation is carried out to the sparse sampling data of each passage;

Distance is carried out to reestablishment imaging to the distance of each localizer unit in each passage to data separate compressed sensing to the orientation after phase compensation;

To the data after reestablishment imaging, phase center antenna (DPCA is split to each channel distance to described orientation, Displaced Phase Center Antenna) process, orientation is carried out to Recovery processing to the Data in Azimuth Direction in each range gate, to carry out two dimensional compaction perception SAR imaging.

Preferably, described to orientation to each channel reception in hyperchannel SAR system to signal carry out two-dimensional random sparse sampling respectively, comprising:

By described orientation to each passage in hyperchannel SAR system in orientation upwards random Received signal strength, upwards carry out Random sparseness sampling to adjust the distance to signal lower than the sample frequency of nyquist frequency in distance.

Preferably, described distance is carried out to reestablishment imaging to the distance of each localizer unit in each passage to data separate compressed sensing to the orientation after phase compensation, comprising:

According to the position of distance to sparse sampling data, the distance of structure correspondence is to observing matrix;

According to minimum l ₁norm criterion, adopts orthogonal matching pursuit algorithm to the distance of each passage to observation data distance to reestablishment imaging.

Preferably, described described orientation is carried out DPCA process to each channel distance to the data after reestablishment imaging, orientation is carried out to Recovery processing to the Data in Azimuth Direction in each range gate, comprising:

To orientation to each passage through distance to the data after reestablishment imaging, rearrange according to DPCA principle;

Construct the sub-observing matrix of each passage to the position relationship of each passage stochastic sampling data according to orientation;

Every sub-observing matrix is carried out corresponding arrangement restructuring structure orientation to total observing matrix;

Utilize minimum l ₁norm criterion and orthogonal matching pursuit algorithm carry out orientation to Recovery processing to the Data in Azimuth Direction in each range gate.

Preferably, the receiving antenna of each passage described in described basis and the relative position relation of central radiator, carry out phase compensation to the sparse sampling data of each passage respectively, comprising:

Adopt phase compensating factor phase compensation is carried out to the sparse sampling data of each passage;

Wherein, i=1,2 ..., N, △ x _ibe the receiving antenna of the i-th passage and the distance of central radiator, N represents that orientation is to port number, and i represents the numbering of the receiving antenna of each passage, d _azrepresent adjacent sub-aperture spacing, λ represents carrier wavelength, R ₀represent the scape center oblique distance of observation scene.

Based on the orientation of compressed sensing to a hyperchannel SAR imaging system, described system comprises: two-dimensional random sparse sampling module, phase compensation block, distance are to reestablishment imaging module and orientation to Recovery processing module; Wherein,

Described two-dimensional random sparse sampling module, for orientation to each channel reception in hyperchannel SAR system to signal carry out two-dimensional random sparse sampling respectively;

Described phase compensation block, for according to the receiving antenna of each passage described and the relative position relation of central radiator, carries out phase compensation to the sparse sampling data of each passage respectively;

Described distance to reestablishment imaging module, for carrying out distance to reestablishment imaging to the orientation after phase compensation to the distance of each localizer unit in each passage to data separate compressed sensing;

Described orientation is to Recovery processing module, for splitting phase center antenna DPCA process to each channel distance to the data after reestablishment imaging to described orientation, orientation is carried out to Recovery processing to the Data in Azimuth Direction in each range gate, to carry out two dimensional compaction perception SAR imaging.

Preferably, described two-dimensional random sparse sampling module, also for by described orientation to each passage in hyperchannel SAR system in orientation upwards random Received signal strength, upwards carry out Random sparseness sampling to adjust the distance to signal lower than the sample frequency of nyquist frequency in distance.

Preferably, described distance, to reestablishment imaging module, also for according to the position of distance to sparse sampling data, constructs corresponding distance to observing matrix; According to minimum l ₁norm criterion, adopts orthogonal matching pursuit algorithm to the distance of each passage to observation data distance to reestablishment imaging.

Preferably, described orientation to Recovery processing module, also for orientation to each passage through distance to the data after reestablishment imaging, rearrange according to DPCA principle; Construct the sub-observing matrix of each passage to the position relationship of each passage stochastic sampling data according to orientation; Every sub-observing matrix is carried out corresponding arrangement restructuring structure orientation to total observing matrix; Utilize minimum l ₁norm criterion and orthogonal matching pursuit algorithm carry out orientation to Recovery processing to the Data in Azimuth Direction in each range gate.

Preferably, described phase compensation block, also for adopting phase compensating factor phase compensation is carried out to the sparse sampling data of each passage;

Wherein, i=1,2 ..., N, △ x _ibe the receiving antenna of the i-th passage and the distance of central radiator, N represents that orientation is to port number, and i represents the numbering of the receiving antenna of each passage, d _azrepresent adjacent sub-aperture spacing, λ represents carrier wavelength, R ₀represent the scape center oblique distance of observation scene.

In the embodiment of the present invention, to orientation to each channel reception in hyperchannel SAR system to signal carry out two-dimensional random sparse sampling respectively; According to the receiving antenna of each passage described and the relative position relation of central radiator, respectively phase compensation is carried out to the sparse sampling data of each passage; Distance is carried out to reestablishment imaging to the distance of each localizer unit in each passage to data separate compressed sensing to the orientation after phase compensation; To the data after reestablishment imaging, phase center antenna DPCA process is split to each channel distance to described orientation, orientation is carried out to Recovery processing to the Data in Azimuth Direction in each range gate, to carry out two dimensional compaction perception SAR imaging.So, greatly reduce the data volume of orientation to hyperchannel SAR system, meanwhile, accurate imaging without the need to being restricted, also can be carried out to observation scene to the PRF of hyperchannel SAR system in orientation.

Accompanying drawing explanation

Fig. 1 is that the orientation based on compressed sensing of the embodiment of the present invention is to the schematic flow sheet of hyperchannel SAR formation method;

Fig. 2 is the geometry imaging model schematic diagram of spaceborne orientation to hyperchannel SAR of inventive embodiments;

Fig. 3 is that the orientation based on compressed sensing of the embodiment of the present invention is to signal processing flow figure in hyperchannel SAR formation method;

Fig. 4 is the two-dimensional random sparse sampling schematic diagram of orientation to each passage of hyperchannel SAR system of the embodiment of the present invention;

Fig. 5 is that the orientation based on compressed sensing of the embodiment of the present invention is to the simulation result schematic diagram of hyperchannel SAR formation method;

Fig. 6 is that conventional one-channel imaging algorithm carries out the simulation result schematic diagram of imaging to full sampled data;

Fig. 7 is that PRF is operated in singular point place filter bank method and carries out adopting matched filtering method orientation to be carried out to the simulation result schematic diagram of one-dimensional image to full sampled data after frequency spectrum is rebuild;

Fig. 8 is that the PRF in the embodiment of the present invention directly utilizes compression sensing method to carry out one dimension reestablishment imaging simulation result schematic diagram to orientation to three sampling data when being operated in singular point;

Fig. 9 be in the embodiment of the present invention based on compressed sensing structure from orientation to hyperchannel SAR imaging system composition schematic diagram.

Embodiment

In order to more at large understand feature of the present invention and technology contents, below in conjunction with accompanying drawing, realization of the present invention is described in detail, the use of appended accompanying drawing explanation only for reference, is not used for limiting the present invention.

The basic thought of the embodiment of the present invention is: first, and orientation carries out two-dimensional random sparse sampling to hyperchannel SAR system to each passage, and carries out phase compensation according to the position relationship between each receiving antenna and central radiator; Then, distance is carried out to reestablishment imaging to data to the distance of each passage after described phase compensation; Carry out DPCA process through distance to the data of each passage after reestablishment imaging by described, then orientation is carried out to recovery to the data in each range gate, thus realize two dimensional compaction and perceive as picture.

Fig. 1 is that the orientation based on compressed sensing of the embodiment of the present invention is to the schematic flow sheet of hyperchannel SAR formation method, the described orientation based on compressed sensing in the embodiment of the present invention is applied to orientation in hyperchannel SAR system to hyperchannel SAR formation method, in a preferred embodiment of the invention, said method comprising the steps of:

Step 101: to orientation to each channel reception in hyperchannel SAR system to signal carry out two-dimensional random sparse sampling respectively.

Preferably, described to orientation to each channel reception in hyperchannel SAR system to signal carry out two-dimensional random sparse sampling respectively, comprising:

By described orientation to each passage in hyperchannel SAR system in orientation upwards random Received signal strength, upwards carry out Random sparseness sampling to adjust the distance to signal lower than the sample frequency of nyquist frequency in distance.

Particularly, to orientation to each channel reception to signal carry out two-dimensional random sparse sampling time, in orientation upwards, central radiator launches limited pulse signal at random, and the receiving antenna that each passage is corresponding receives limited echoed signal respectively; Distance upwards, is carried out Random sparseness sampling to the signal of each channel reception by the frequency far below nyquist frequency, thus is realized the two-dimensional random sparse sampling of each passage.

Step 102: according to the receiving antenna of each passage described and the relative position relation of central radiator, carries out phase compensation to the sparse sampling data of each passage respectively.

Particularly, phase compensating factor is adopted phase compensation is carried out to the sparse sampling data of each passage;

Wherein, i=1,2 ..., N, △ x _ibe the receiving antenna of the i-th passage and the distance of central radiator, N represents that orientation is to port number, and i represents the numbering of the receiving antenna of each passage, d _azrepresent adjacent sub-aperture spacing, λ represents carrier wavelength, R ₀represent the scape center oblique distance of observation scene.

Above-mentioned parameter in the present embodiment can refer to the spaceborne orientation shown in Fig. 2 and understands to the geometry imaging model schematic diagram of hyperchannel SAR.

Step 103: distance is carried out to reestablishment imaging to the distance of each localizer unit in each passage to data separate compressed sensing to the orientation after phase compensation.

Preferably, described distance is carried out to reestablishment imaging to the distance of each localizer unit in each passage to data separate compressed sensing to the orientation after phase compensation, comprising:

According to the position of distance to sparse sampling data, the distance of structure correspondence is to observing matrix;

According to minimum l ₁norm criterion, adopts orthogonal matching pursuit algorithm to the distance of each passage to observation data distance to reestablishment imaging.

Particularly, first utilize the waveform that transmits to build observation dictionary as atom, according to the distance of each passage position to sparse sampling data, build corresponding distance to observing matrix, then utilize the distance of each passage to observation data and distance to observing matrix, based on minimum l ₁norm criterion, adopts orthogonal matching pursuit algorithm to realize distance to reestablishment imaging;

The distance of described structure to observing matrix is: Φ _r(p, q)=S _t((ω (p)-q) × △ τ);

Wherein, p, q are respectively line number and the columns of observing matrix, S _tfor distance is to transmitted waveform, ω (p) is for distance is to the position sequence of stochastic sampling data, and △ τ is the time interval of distance to nyquist sampling.

Described minimum l ₁norm criterion is: s.t.y=Θ α

Wherein, for the backscattering coefficient estimated value of each range unit, α is the true backscattering coefficient of each range unit, argmin for getting function minimum, y be distance in each localizer unit to random observation data, Θ is that corresponding distance is to observing matrix.

Step 104: carry out DPCA process to each channel distance to the data after reestablishment imaging to described orientation, carries out orientation to Recovery processing to the Data in Azimuth Direction in each range gate, to carry out two dimensional compaction perception SAR imaging.

Preferably, described described orientation is carried out DPCA process to each channel distance to the data after reestablishment imaging, orientation is carried out to Recovery processing to the Data in Azimuth Direction in each range gate, comprising:

To orientation to each passage through distance to the data after reestablishment imaging, rearrange according to DPCA principle;

Construct the sub-observing matrix of each passage to the position relationship of each passage stochastic sampling data according to orientation;

Every sub-observing matrix is carried out corresponding arrangement restructuring structure orientation to total observing matrix;

Utilize minimum l ₁norm criterion and orthogonal matching pursuit algorithm carry out orientation to Recovery processing to the Data in Azimuth Direction in each range gate.

Particularly, first according to orientation to random exomonental position, build each passage orientation to sub-observing matrix, then rearrange according to DPCA principle to observation data completing the orientation of distance to each passage rebuild, structure orientation is rearranged accordingly to total observing matrix, finally based on minimum l to sub-observing matrix to each orientation simultaneously ₁norm criterion, utilizes orthogonal matching pursuit algorithm to complete the recovery of orientation to observation scene, thus realizes orientation and perceive as picture to the two dimensional compaction of hyperchannel SAR.

The orientation of described each passage to sub-observing matrix is:

${\mathrm{\Φ}}_{\mathrm{ai}}(k,l)=\mathrm{rect}\left[\frac{(\mathrm{\ω}\left(k\right)\×N-1)\×\mathrm{\Δ}{t}^{\′}}{T_a}\right]\×\exp (-j\×2\×\mathrm{\π}\×f_0\×R_i\×((\mathrm{\ω}\left(k\right)\×N-1)\×\mathrm{\Δ}{t}^{\′},n_0\mathrm{\Δ\τ})/c)$

i=1,2,…,N

Wherein, k, l are respectively line number and the columns of the sub-observing matrix of the i-th passage, and rect is rectangular window function, ω (k) for orientation is to random exomonental position sequence, N be orientation to port number, t _afor orientation is to the synthetic aperture time, f ₀for carrier wavelength, R _ifor the round oblique distance transmitted from emitting antenna to i-th receiving antenna, n ₀for range gate sequence, c represents the light velocity.

Described orientation to total observing matrix is: ${\mathrm{\Φ}}_a={[{\mathrm{\Φ}}_{a1}^{\left(1\right)}\·\·\·{\mathrm{\Φ}}_{\mathrm{aN}}^{\left(1\right)}\·\·\·{\mathrm{\Φ}}_{a1}^{\left(K\right)}\·\·\·{\mathrm{\Φ}}_{\mathrm{aN}}^{\left(K\right)}]}^T$

Wherein represent the of i-th sub-observing matrix _koK, [] ^tthe transposition of representing matrix.

Fig. 3 be the orientation based on compressed sensing of the embodiment of the present invention to signal processing flow figure in hyperchannel SAR formation method, in a preferred embodiment of the invention, said method comprising the steps of:

Step 301: to orientation to each channel reception in hyperchannel SAR system to signal carry out two-dimensional random sparse sampling; And according to the relative position relation between the receiving antenna of each passage and central radiator, phase compensation is carried out to the sparse sampling data of each passage.

Here, as shown in Figure 4, black unit represents the position of actual samples data to the two-dimensional random sparse sampling result of the signal that each channel reception arrives.

Step 302: distance is carried out to reestablishment imaging to the distance of each localizer unit in each passage to data separate compression sensing method to the orientation after described phase compensation.

Step 303: described orientation is carried out DPCA process to each channel distance to the data after reestablishment imaging; Orientation is carried out to recovery to the Data in Azimuth Direction in each range gate, to realize two dimensional compaction perception SAR imaging.

The present embodiment and traditional orientation are to the key distinction of hyperchannel SAR imaging algorithm: the present embodiment is by each receiving cable two-dimensional random sparse sampling, significantly reduce the sampled data output of system, compression sensing method can be utilized directly to realize observing the accurate imaging of scene for non-homogeneous signal simultaneously, rebuild pre-service without the need to carrying out frequency spectrum with filter bank method, orientation can be realized to the fuzzy effective suppression of decoy.Originally routine simulation system parameters is executed as shown in table 1:

Orientation is to sub-aperture number N	3
		Carrier wavelength lambda	0.03m
Texas tower height H	495km
		Oblique distance R	700km
Orientation is to antenna length L	12.6m
		Transmitted signal bandwidth B r	66.4MHz
Orientation is to sub-aperture length d az	4.15m
		Wide T during transponder pulse r	5μs
Platform speed V s	7500m/s
		Pulse repetition rate PRF	1500Hz
Incidence angle θ	45°
		Distance down sample speed	3 times
Orientation down sample speed	3 times

Table 1

As shown in Table 1, systematic parameter is in nonuniform sampling mode of operation.Fig. 5 adopts orientation based on compressed sensing to the simulation result of hyperchannel SAR formation method.The reconstruction of bank of filters frequency spectrum is not carried out for full sampled data, directly utilizes conventional one-channel RD algorithm to carry out the simulation result of imaging as shown in Figure 6.Based on the false target problem that the orientation of compressed sensing can effectively suppress because nonuniform sampling causes to hyperchannel SAR imaging algorithm, realize the accurate imaging of observation scene.

It should be noted that, for non-uniformly sampled signals, when PRF is operated in particular value, system true bearing there will be aliasing to sampled data, traditional bank of filters frequency spectrum reconstruction algorithm becomes unstable owing to relating to matrix inversion operation, namely system PRF exists singular point for bank of filters method for reconstructing.When PRF is operated in singular point place, adopts filter bank method to carry out frequency spectrum and rebuild and will lose efficacy, cause the rising of secondary lobe.And there is not restriction requirement for PRF based on the orientation of compressed sensing to hyperchannel SAR imaging algorithm, for the PRF situation being in singular point place, the accurate recovery observing scene also can be realized.

When PRF is operated near singular point 1807Hz, when other parameter is with table 1, Fig. 7 adopts matched filtering method to carry out the simulation result of one-dimensional image to full sampled data after bank of filters frequency spectrum is rebuild, and Fig. 8 utilizes three times of down-sampled data directly to adopt the method based on compressed sensing to carry out the orientation of one-dimensional image to restoration result.

Can find out from simulation result, when the PRF of system is operated in singular point, bank of filters frequency spectrum method for reconstructing obviously lost efficacy, and can utilize based on the method for compressed sensing and just can realize the accurate recovery of orientation to observation scene far below the data volume of full sampling.

Fig. 9 be in the embodiment of the present invention based on compressed sensing structure from orientation to hyperchannel SAR imaging system composition schematic diagram, as described in Figure 9, described system comprises: two-dimensional random sparse sampling module 91, phase compensation block 92, distance are to reestablishment imaging module 93 and orientation to Recovery processing module 94; Wherein,

Described two-dimensional random sparse sampling module 91, for orientation to each channel reception in hyperchannel SAR system to signal carry out two-dimensional random sparse sampling respectively;

Described phase compensation block 92, for according to the receiving antenna of each passage described and the relative position relation of central radiator, carries out phase compensation to the sparse sampling data of each passage respectively;

Described distance to reestablishment imaging module 93, for carrying out distance to reestablishment imaging to the orientation after phase compensation to the distance of each localizer unit in each passage to data separate compressed sensing;

Described orientation is to Recovery processing module 94, for splitting phase center antenna DPCA process to each channel distance to the data after reestablishment imaging to described orientation, orientation is carried out to Recovery processing to the Data in Azimuth Direction in each range gate, to carry out two dimensional compaction perception SAR imaging.

Preferably, described two-dimensional random sparse sampling module 91, also for by described orientation to each passage in hyperchannel SAR system in orientation upwards random Received signal strength, upwards carry out Random sparseness sampling to adjust the distance to signal lower than the sample frequency of nyquist frequency in distance.

Preferably, described distance, to reestablishment imaging module 93, also for according to the position of distance to sparse sampling data, constructs corresponding distance to observing matrix; According to minimum l ₁norm criterion, adopts orthogonal matching pursuit algorithm to the distance of each passage to observation data distance to reestablishment imaging.

Preferably, described orientation to Recovery processing module 94, also for orientation to each passage through distance to the data after reestablishment imaging, rearrange according to DPCA principle; Construct the sub-observing matrix of each passage to the position relationship of each passage stochastic sampling data according to orientation; Every sub-observing matrix is carried out corresponding arrangement restructuring structure orientation to total observing matrix; Utilize minimum l ₁norm criterion and orthogonal matching pursuit algorithm carry out orientation to Recovery processing to the Data in Azimuth Direction in each range gate.

Preferably, described phase compensation block 92, also for adopting phase compensating factor phase compensation is carried out to the sparse sampling data of each passage;

Wherein, i=1,2 ..., N, △ x _ibe the receiving antenna of the i-th passage and the distance of central radiator, N represents that orientation is to port number, and i represents the numbering of the receiving antenna of each passage, d _azrepresent adjacent sub-aperture spacing, λ represents carrier wavelength, R ₀represent the scape center oblique distance of observation scene.

It will be appreciated by those skilled in the art that the orientation based on compressed sensing shown in Fig. 9 can refer to the aforementioned orientation based on compressed sensing to the practical function of each module in hyperchannel SAR imaging system and understands to the associated description of hyperchannel SAR formation method.The orientation based on compressed sensing shown in Fig. 9 realizes to the function of each module in hyperchannel SAR imaging system by the program run on processor, also realizes by concrete logical circuit.

The above, be only preferred embodiment of the present invention, be not intended to limit protection scope of the present invention.

Claims (10)

1. based on the orientation of compressed sensing to a Multichannel SAR SAR formation method, be applied to orientation to hyperchannel SAR system, it is characterized in that, described method comprises:

To orientation to each channel reception in hyperchannel SAR system to signal carry out two-dimensional random sparse sampling respectively;

According to the receiving antenna of each passage described and the relative position relation of central radiator, respectively phase compensation is carried out to the sparse sampling data of each passage;

Distance is carried out to reestablishment imaging to the distance of each localizer unit in each passage to data separate compressed sensing to the orientation after phase compensation;

To the data after reestablishment imaging, phase center antenna DPCA process is split to each channel distance to described orientation, orientation is carried out to Recovery processing to the Data in Azimuth Direction in each range gate, to carry out two dimensional compaction perception SAR imaging.

2. method according to claim 1, is characterized in that, described to orientation to each channel reception in hyperchannel SAR system to signal carry out two-dimensional random sparse sampling respectively, comprising:

By described orientation to each passage in hyperchannel SAR system in orientation upwards random Received signal strength, upwards carry out Random sparseness sampling to adjust the distance to signal lower than the sample frequency of nyquist frequency in distance.

3. method according to claim 1, is characterized in that, describedly carries out distance to reestablishment imaging to the orientation after phase compensation to the distance of each localizer unit in each passage to data separate compressed sensing, comprising:

According to the position of distance to sparse sampling data, the distance of structure correspondence is to observing matrix;

According to minimum l ₁norm criterion, adopts orthogonal matching pursuit algorithm to the distance of each passage to observation data distance to reestablishment imaging.

4. method according to claim 1, it is characterized in that, described to the data after reestablishment imaging, phase center antenna DPCA process is split to each channel distance to described orientation, orientation is carried out to Recovery processing to the Data in Azimuth Direction in each range gate, comprising:

To orientation to each passage through distance to the data after reestablishment imaging, rearrange according to DPCA principle;

Construct the sub-observing matrix of each passage to the position relationship of each passage stochastic sampling data according to orientation;

Every sub-observing matrix is carried out corresponding arrangement restructuring structure orientation to total observing matrix;

Utilize minimum l ₁norm criterion and orthogonal matching pursuit algorithm carry out orientation to Recovery processing to the Data in Azimuth Direction in each range gate.

5. the method according to any one of Claims 1-4, is characterized in that, the receiving antenna of each passage described in described basis and the relative position relation of central radiator, carries out phase compensation respectively, comprising the sparse sampling data of each passage:

Adopt phase compensating factor phase compensation is carried out to the sparse sampling data of each passage;

Wherein, i=1,2 ..., N, Δ x _ibe the receiving antenna of the i-th passage and the distance of central radiator, N represents that orientation is to port number, and i represents the numbering of the receiving antenna of each passage, d _azrepresent adjacent sub-aperture spacing, λ represents carrier wavelength, R ₀represent the scape center oblique distance of observation scene.

6. based on the orientation of compressed sensing to a hyperchannel SAR imaging system, it is characterized in that, described system comprises: two-dimensional random sparse sampling module, phase compensation block, distance are to reestablishment imaging module and orientation to Recovery processing module; Wherein,

Described two-dimensional random sparse sampling module, for orientation to each channel reception in hyperchannel SAR system to signal carry out two-dimensional random sparse sampling respectively;

Described phase compensation block, for according to the receiving antenna of each passage described and the relative position relation of central radiator, carries out phase compensation to the sparse sampling data of each passage respectively;

Described distance to reestablishment imaging module, for carrying out distance to reestablishment imaging to the orientation after phase compensation to the distance of each localizer unit in each passage to data separate compressed sensing;

Described orientation is to Recovery processing module, for splitting phase center antenna DPCA process to each channel distance to the data after reestablishment imaging to described orientation, orientation is carried out to Recovery processing to the Data in Azimuth Direction in each range gate, to carry out two dimensional compaction perception SAR imaging.

7. system according to claim 6, it is characterized in that, described two-dimensional random sparse sampling module, also for by described orientation to each passage in hyperchannel SAR system in orientation upwards random Received signal strength, upwards carry out Random sparseness sampling to adjust the distance to signal lower than the sample frequency of nyquist frequency in distance.

8. system according to claim 6, is characterized in that, described distance, to reestablishment imaging module, also for according to the position of distance to sparse sampling data, constructs corresponding distance to observing matrix; According to minimum l ₁norm criterion, adopts orthogonal matching pursuit algorithm to the distance of each passage to observation data distance to reestablishment imaging.

9. system according to claim 6, is characterized in that, described orientation to Recovery processing module, also for orientation to each passage through distance to the data after reestablishment imaging, rearrange according to DPCA principle; Construct the sub-observing matrix of each passage to the position relationship of each passage stochastic sampling data according to orientation; Every sub-observing matrix is carried out corresponding arrangement restructuring structure orientation to total observing matrix; Utilize minimum l ₁norm criterion and orthogonal matching pursuit algorithm carry out orientation to Recovery processing to the Data in Azimuth Direction in each range gate.

10. the system according to any one of claim 6 to 9, is characterized in that, described phase compensation block, also for adopting phase compensating factor the sparse sampling data line phase of each passage is compensated;

Wherein, i=1,2 ..., N, Δ x _ibe the receiving antenna of the i-th passage and the distance of central radiator, N represents that orientation is to port number, and i represents the numbering of the receiving antenna of each passage, d _azrepresent adjacent sub-aperture spacing, λ represents carrier wavelength, R ₀represent the scape center oblique distance of observation scene.