CN116400310A - Two-dimensional frequency domain azimuth multi-channel SAR error correction method - Google Patents
Two-dimensional frequency domain azimuth multi-channel SAR error correction method Download PDFInfo
- Publication number
- CN116400310A CN116400310A CN202310596689.8A CN202310596689A CN116400310A CN 116400310 A CN116400310 A CN 116400310A CN 202310596689 A CN202310596689 A CN 202310596689A CN 116400310 A CN116400310 A CN 116400310A
- Authority
- CN
- China
- Prior art keywords
- echo signals
- channel
- channels
- frequency domain
- error correction
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000012937 correction Methods 0.000 title claims abstract description 35
- 238000000034 method Methods 0.000 title claims abstract description 26
- 238000005457 optimization Methods 0.000 claims abstract description 14
- 238000003384 imaging method Methods 0.000 claims abstract description 13
- 238000001228 spectrum Methods 0.000 claims description 8
- 230000009466 transformation Effects 0.000 abstract description 2
- 230000001131 transforming effect Effects 0.000 abstract 1
- 239000004973 liquid crystal related substance Substances 0.000 description 20
- 238000005070 sampling Methods 0.000 description 6
- 238000012545 processing Methods 0.000 description 5
- 239000011159 matrix material Substances 0.000 description 4
- 238000013507 mapping Methods 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 241000282898 Sus scrofa Species 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000005286 illumination Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000000149 penetrating effect Effects 0.000 description 1
- 238000011045 prefiltration Methods 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
- G01S7/40—Means for monitoring or calibrating
- G01S7/4004—Means for monitoring or calibrating of parts of a radar system
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
- G01S13/88—Radar or analogous systems specially adapted for specific applications
- G01S13/89—Radar or analogous systems specially adapted for specific applications for mapping or imaging
- G01S13/90—Radar or analogous systems specially adapted for specific applications for mapping or imaging using synthetic aperture techniques, e.g. synthetic aperture radar [SAR] techniques
- G01S13/9021—SAR image post-processing techniques
Landscapes
- Engineering & Computer Science (AREA)
- Remote Sensing (AREA)
- Radar, Positioning & Navigation (AREA)
- Physics & Mathematics (AREA)
- Computer Networks & Wireless Communication (AREA)
- General Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Radar Systems Or Details Thereof (AREA)
Abstract
The invention discloses a two-dimensional frequency domain azimuth multichannel SAR error correction method, which comprises the following steps: receiving echo signals of a plurality of channels, wherein the echo signals are sampled at a first pulse repetition frequency; performing amplitude error estimation and correction on the received echo signals of the channels; performing azimuth and distance fast Fourier transformation on the multichannel echo signals subjected to amplitude error correction, and transforming the two-dimensional time domain echo signals into two-dimensional frequency domain echo signals; the two-dimensional frequency domain echo signals of each channel are summed up after phase compensation to establish an L1 norm maximization optimization model; carrying out iterative solution by using a global optimal algorithm to obtain accurate phase errors and carrying out phase error correction on echo signals of all channels; reconstructing the multichannel signal sampled at the first pulse repetition frequency after the phase error correction into a single-channel echo signal sampled at the second pulse repetition frequency; and obtaining a high-resolution wide SAR image without false targets by using an imaging algorithm.
Description
Technical Field
The invention relates to the technical field of radars, in particular to a two-dimensional frequency domain azimuth multi-channel SAR error correction method.
Background
Synthetic aperture radar (Synthetic Aperture Radar, SAR) uses synthetic aperture imaging with high resolution in azimuth. The synthetic aperture radar is used as an active remote sensor working in a microwave frequency band, is not influenced by weather and illumination conditions, can observe the ground all the time and all the weather, has certain penetrating capacity, can acquire information below the ground surface, and therefore, the synthetic aperture radar is rapidly developed in the past decades and has important application in the field of modern microwave remote sensing. In order to monitor a wider range of scene information and provide finer scene information, higher resolution and wider mapping breadth are the necessary trends in the development of the microwave remote sensing field. The azimuth multi-channel technology improves time sampling by space sampling equivalent, solves the contradiction between the azimuth high resolution and the distance wide mapping band of the traditional spaceborne SAR, and becomes one of the important systems for realizing high-resolution wide SAR imaging at present.
The azimuth multi-channel SAR system mainly adopts an offset phase center azimuth multi-beam system, and adopts a working mode of single-channel transmission and multi-channel reception by dividing an antenna into a plurality of equally-spaced sub-apertures. The azimuth multi-channel SAR system transmits a chirp signal at a low pulse repetition frequency (Pulse Repetition Frequency, PRF) and achieves an increase in range-to-swath width by increasing the length of the signal receiving window. Meanwhile, the echo signals received by each sub-aperture can be equivalently self-received echo signals in the equivalent phase center, the time sampling rate is increased by increasing the space sampling equivalent, and the PRF is ensured to meet the Nyquist sampling theorem, so that the azimuth resolution is unchanged while the distance mapping bandwidth is increased. However, the introduction of multiple channels also brings about various errors, so that system parameters are changed, the mismatch between the reconstruction filter and the multiple channels of echo signals is caused by the inconsistent channels, and fuzzy energy is introduced into the reconstructed single channel echo signals, so that the performance of the azimuth multi-channel SAR system is severely restricted. The amplitude and phase errors among the channels have the most serious influence on the reconstructed signals, so that the amplitude and phase consistency correction among the channels becomes a key link in the signal processing of the azimuth multi-channel SAR system.
In the current developed channel phase error correction method, the signal subspace method and the image domain method are mainly adopted, however, under the condition of low signal-to-noise ratio, the signal subspace and the noise subspace are difficult to separate, so that the correction performance of the method is greatly affected. In addition, the signal subspace type method needs additional redundant channels, and limits the application scene of the method. The image domain method has high estimation precision and good stability, but needs to carry out imaging processing on the multichannel signals, and estimates channel errors by processing a plurality of images, so that the calculated amount is large.
Disclosure of Invention
In order to solve the technical problems, the invention provides a two-dimensional frequency domain azimuth multi-channel SAR error correction method, wherein a sum L1 norm maximization optimization model of multi-channel echo signals is established in a two-dimensional frequency domain, a global optimization algorithm is utilized to iteratively solve channel phase errors, so that amplitude and phase errors among channels can be accurately corrected, and false targets of SAR image azimuth can be eliminated.
In order to achieve the above purpose, the invention adopts the following technical scheme:
a two-dimensional frequency domain azimuth multi-channel SAR error correction method comprises the following steps:
step 3, compensating phases caused by the interval distances between corresponding equivalent phase centers and phase centers of reference channels for the two-dimensional frequency domain echo signals of each channel, and summing the two-dimensional frequency domain multi-channel echo signals after compensating the phases to establish an L1 norm maximization optimization model;
step 4, carrying out iterative solution by using a global optimal algorithm to obtain accurate phase errors, and carrying out phase error correction on echo signals of all channels;
step 5, reconstructing the multichannel signal sampled at the first pulse repetition frequency after the phase error correction into a single-channel echo signal sampled at a second pulse repetition frequency, wherein the second pulse repetition frequency is higher than the first pulse repetition frequency;
and 6, obtaining a high-resolution wide SAR image without direction blurring by using a CS imaging algorithm.
Further, the step 1 includes:
carrying out azimuth Fourier transform on echo signals of a plurality of channels, taking an average value of amplitude spectrums along azimuth and distance directions, and taking the average value of the amplitude spectrums of the echo signals of the channels and the average value of the amplitude spectrums of a reference channel as a quotient to obtain amplitude error estimation; and then carrying out amplitude correction on echo signals of the channels according to the estimated amplitude errors.
Further, the step 3 includes:
and compensating a linear phase generated by an equivalent phase center interval for each channel of two-dimensional frequency domain echo signals, summing corresponding frequency points of the compensated two-dimensional frequency domain multi-channel echo signals in the azimuth direction, establishing an L1 norm maximization optimization model, and carrying out iterative solution by using a global optimization algorithm to obtain an accurate phase error.
The beneficial effects are that:
compared with the existing signal subspace method and image domain method, the method fully utilizes the sparse characteristic of the L1 norm, can show excellent estimation performance even under the condition of low signal-to-noise ratio, accurately corrects phase errors and obtains imaging results without false targets. In addition, the invention does not need to image the multichannel signals respectively, and only needs to convert the two-dimensional time domain echo signals into the two-dimensional frequency domain echo signals when estimating the channel errors, and the two-dimensional frequency domain echo signals are summed after compensating the phases, so that the calculation speed is further improved while the estimation precision is maintained.
Drawings
FIG. 1 is a flow chart of a two-dimensional frequency domain azimuth multi-channel SAR error correction method of the present invention;
FIG. 2 is a schematic diagram of a satellite-borne azimuth multi-channel SAR operating mechanism;
FIG. 3 is a graph of imaging results of GF-3 satellite dual-channel data without error correction;
FIG. 4 is a graph of the results of error correction for GF-3 satellite dual channel data.
Detailed Description
The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are only some embodiments of the present invention, but not all embodiments, and all other embodiments obtained by those skilled in the art without the inventive effort based on the embodiments of the present invention are within the scope of protection of the present invention.
According to an embodiment of the present invention, as shown in fig. 1, the two-dimensional frequency domain azimuth multi-channel SAR error correction method of the present invention comprises the following steps:
step 101: and carrying out amplitude error estimation and compensation on the received echo signals of the channels by using a channel equalization method.
The multi-channel echo signal with amplitude and phase errors is represented as follows:
wherein, the liquid crystal display device comprises a liquid crystal display device,and->Respectively represent +.>The flow path of the liquid is provided with a channel,two-dimensional time-domain echo signal with channel error and without channel error,>and->Respectively represent->Amplitude error and phase error of the channel, +.>And->Representing distance fast time and azimuth slow time, respectively, < >>,/>For the number of channels>Representing natural number->Index (I)>Representing imaginary units.
The channel amplitude error and the phase error of the azimuth multi-channel SAR system are mutually independent and can be corrected separately. The amplitude error between channels is generally corrected, and the amplitude error estimated valueThe method can be obtained by a channel equalization method, and firstly, azimuth fast Fourier transform is carried out on echo signals of all channels:
wherein, the liquid crystal display device comprises a liquid crystal display device,representing the azimuthal fast fourier transform, +.>Indicating Doppler frequency, ++>For the first pulse repetition frequency, < >>Indicate->The channel error signal over the range-doppler domain, the amplitude error estimate results are as follows:
wherein, the liquid crystal display device comprises a liquid crystal display device,and->Respectively representing the desire along the distance direction and the azimuth direction, taking the 1 st channel as the reference channel, and the +.>Representing the error-free signal of the reference channel over the range-doppler domain. Thus correct the +.o after amplitude error correction>Channel echo signal->The following are provided:
step 102: the multichannel signal sampled by the first pulse repetition frequency which completes the amplitude error correction is transformed into a two-dimensional frequency domain multichannel echo signal through fast Fourier transformation.
In the amplitude error correction of step 101, the multichannel echo signal has completed the azimuthal fast fourier transform, so after the amplitude error correction, the multichannel echo signal is further subjected to the distance fast fourier transform, and then there are:
wherein, the liquid crystal display device comprises a liquid crystal display device,the +.o. indicating completion of amplitude error correction>Channel two-dimensional frequency domain echo signal>Represents distance frequency, and is omitted in the following>Will->Simplified to->,/>Representing the distance to fast fourier transform.
Step 103: compensating phases for the echo signals of the two-dimensional frequency domains of all channels, and summing to establish an L1 norm maximization optimization model;
a schematic diagram of the azimuth multi-channel SAR operating mechanism is shown in fig. 2, wherein,indicating the most recent pitch of the circle,indicating the skew history between the transmit aperture and the target,/->Indicate->The skew between the individual receive apertures to the target,/->Indicate->Skew history between the center of each equivalent phase and the target,/->Representing the spacing between adjacent apertures, having a length of 4.9m; the first pulse repetition frequency is PRF. Taking an azimuthal dual-channel SAR as an example, setting the first channel as a reference channel, the matrix form of the error-free multi-channel received signal represents:
wherein, the liquid crystal display device comprises a liquid crystal display device,no. I representing the aliasing free spectrum of the reference channel>Sub-band, < >>Which is indicative of the velocity of the satellite,is a system pre-filter matrix,/->Represents the 1 st subband, ">Indicate->A sub-band. />Indicate->Length of interval between each channel and reference channel:
the azimuth frequency domain echo signal expression of each channel can be known from the expression (6) as follows:
wherein, the liquid crystal display device comprises a liquid crystal display device,first +.>The frequency points of the frequency spectrum are selected,,/>indicating the number of azimuthal sampling points at the first pulse repetition frequency,/for>And->Respectively representing the 1 st sub-band and the 2 nd sub-bandBand->Frequency points. Thus, compensating the echo signal of the second channel for phase +.>Obtaining:
at this time, an L1 norm model of the sum of two-dimensional frequency domain multi-channel echo signals can be established:
Wherein, the liquid crystal display device comprises a liquid crystal display device,is the channel phase error estimate for the second channel. Then an L1 norm maximization optimization model is built:
wherein, the liquid crystal display device comprises a liquid crystal display device,express +.>Maximized estimated phase error +.>。
Step 104: the global optimization algorithm is utilized to carry out iterative solution to obtain accurate phase errors, and the phase errors of echo signals of all channels are corrected;
to use the global optimization algorithm, the maximization model of equation (12) is rewritten as:
wherein, the liquid crystal display device comprises a liquid crystal display device,express +.>Minimized estimated phase error +.>. Obtaining a phase error estimate by using a global optimization algorithm>The phase error correction for the second channel is as follows:
step 105: reconstructing the multichannel signal sampled at the first pulse repetition frequency after the phase error correction into a single-channel echo signal sampled at a second pulse repetition frequency, wherein the second pulse repetition frequency is higher than the first pulse repetition frequency;
first by distance inverse fast fourier transformConverting the two-dimensional frequency domain channel echo signals into range-doppler domain echo signals:
using reconstruction filter matrices according to multichannel signal reconstruction techniquesAnd carrying out reconstruction processing on the multichannel received signal subjected to channel error compensation:
wherein, the liquid crystal display device comprises a liquid crystal display device,and->Representing the reconstructed second pulse repetition frequency sampled single-channel echo signal and the channel error corrected first pulse repetition frequency sampled multi-channel echo signal matrix respectively.,/>Representing reconstruction Filter matrix->Is>Row vector->Representing a transmission matrix filter->Representing the Doppler frequency after reconstruction, < >>。
Step 106: and obtaining the high-resolution wide SAR image without the direction blurring by using a CS imaging algorithm.
The final imaging work can be completed by selecting a single-channel signal imaging algorithm, and the invention adopts CS imagingLike an algorithm. Let the system function of CS algorithm imaging process beThe following steps are:
Example 1
In the embodiment, star-high-resolution No. three (GF-3) satellite dual-channel actual measurement data are selected for processing, and the scene image is acquired on 13 days of 3 months in 2018 and is positioned in a pig seedling lagoon area in the northwest direction of mountain city in Japanese county.
Fig. 3 shows the imaging results without error correction. Wherein the ghosts in the upper and lower boxes of fig. 3 are generated by the object in the middle box. The azimuth blurring in the image is very serious, the real pig-raising lake is submerged by the false target, and the two false targets generated by the pig-raising lake submerge the original real target.
Fig. 4 shows the results after correction by the algorithm of the present invention. The amplitude and phase errors of the channel 2 relative to the channel 1 estimated by the algorithm of the invention are-0.4257 dB and-0.4257 dB respectively. It can be seen that the azimuth ambiguity in fig. 3 has almost completely disappeared and false objects are effectively suppressed.
The foregoing is merely a few examples of the present invention, and the present invention is applicable in other situations and is not intended to limit the scope of the present invention.
Claims (3)
1. A two-dimensional frequency domain azimuth multi-channel SAR error correction method is characterized by comprising the following steps:
step 1, receiving echo signals of a plurality of channels, and estimating and compensating amplitude errors of the received echo signals of the channels; the echo signal is sampled at a first pulse repetition frequency;
step 2, converting echo signals of a plurality of channels sampled by the first pulse repetition frequency after finishing amplitude error correction into two-dimensional frequency domain multi-channel echo signals through fast Fourier transform;
step 3, compensating phases caused by the interval distances between corresponding equivalent phase centers and phase centers of reference channels for the two-dimensional frequency domain echo signals of each channel, and summing the two-dimensional frequency domain multi-channel echo signals after compensating the phases to establish an L1 norm maximization optimization model;
step 4, carrying out iterative solution by using a global optimal algorithm to obtain accurate phase errors, and carrying out phase error correction on echo signals of all channels;
step 5, reconstructing the multichannel signal sampled at the first pulse repetition frequency after the phase error correction into a single-channel echo signal sampled at a second pulse repetition frequency, wherein the second pulse repetition frequency is higher than the first pulse repetition frequency;
and 6, obtaining a high-resolution wide SAR image without direction blurring by using a CS imaging algorithm.
2. The method for correcting two-dimensional frequency domain azimuth multi-channel SAR error according to claim 1, wherein said step 1 comprises:
carrying out azimuth Fourier transform on echo signals of a plurality of channels, taking an average value of amplitude spectrums along azimuth and distance directions, and taking the average value of the amplitude spectrums of the echo signals of the channels and the average value of the amplitude spectrums of a reference channel as a quotient to obtain amplitude error estimation; and then carrying out amplitude correction on echo signals of the channels according to the estimated amplitude errors.
3. The method for correcting two-dimensional frequency domain azimuth multi-channel SAR error according to claim 2, wherein said step 3 comprises:
and compensating a linear phase generated by an equivalent phase center interval for each channel of two-dimensional frequency domain echo signals, summing corresponding frequency points of the compensated two-dimensional frequency domain multi-channel echo signals in the azimuth direction, establishing an L1 norm maximization optimization model, and carrying out iterative solution by using a global optimization algorithm to obtain an accurate phase error.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202310596689.8A CN116400310B (en) | 2023-05-25 | 2023-05-25 | Two-dimensional frequency domain azimuth multi-channel SAR error correction method |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202310596689.8A CN116400310B (en) | 2023-05-25 | 2023-05-25 | Two-dimensional frequency domain azimuth multi-channel SAR error correction method |
Publications (2)
Publication Number | Publication Date |
---|---|
CN116400310A true CN116400310A (en) | 2023-07-07 |
CN116400310B CN116400310B (en) | 2023-07-28 |
Family
ID=87012537
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN202310596689.8A Active CN116400310B (en) | 2023-05-25 | 2023-05-25 | Two-dimensional frequency domain azimuth multi-channel SAR error correction method |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN116400310B (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN116679277A (en) * | 2023-07-26 | 2023-09-01 | 中国科学院空天信息创新研究院 | Minimum L based on time-frequency domain 1 Double-channel SAR multi-jammer positioning method based on norm |
CN116718995B (en) * | 2023-08-09 | 2023-10-10 | 中国科学院空天信息创新研究院 | Azimuth multichannel SAR phase error correction method based on minimum spectrum difference |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2009025159A (en) * | 2007-07-19 | 2009-02-05 | Mitsubishi Electric Corp | Radar device |
CN102901964A (en) * | 2012-09-06 | 2013-01-30 | 内蒙古工业大学 | Two-dimensional multi-aperture scan synthetic aperture radar (SAR) imaging method |
CN103630897A (en) * | 2012-08-28 | 2014-03-12 | 中国科学院电子学研究所 | Multichannel synthetic aperture radar imaging method |
CN108279404A (en) * | 2018-01-22 | 2018-07-13 | 西安电子科技大学 | A kind of Dual-Channel SAR phase error correction approach based on Estimation of Spatial Spectrum |
CN113687356A (en) * | 2021-09-16 | 2021-11-23 | 中国科学院空天信息创新研究院 | Airborne multi-channel circular track SAR moving target detection and estimation method |
CN113933804A (en) * | 2021-12-16 | 2022-01-14 | 中国科学院空天信息创新研究院 | Image domain azimuth multi-channel SAR error correction method |
CN114545411A (en) * | 2022-04-21 | 2022-05-27 | 南京信息工程大学 | Polar coordinate format multimode high-resolution SAR imaging method based on engineering realization |
-
2023
- 2023-05-25 CN CN202310596689.8A patent/CN116400310B/en active Active
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2009025159A (en) * | 2007-07-19 | 2009-02-05 | Mitsubishi Electric Corp | Radar device |
CN103630897A (en) * | 2012-08-28 | 2014-03-12 | 中国科学院电子学研究所 | Multichannel synthetic aperture radar imaging method |
CN102901964A (en) * | 2012-09-06 | 2013-01-30 | 内蒙古工业大学 | Two-dimensional multi-aperture scan synthetic aperture radar (SAR) imaging method |
CN108279404A (en) * | 2018-01-22 | 2018-07-13 | 西安电子科技大学 | A kind of Dual-Channel SAR phase error correction approach based on Estimation of Spatial Spectrum |
CN113687356A (en) * | 2021-09-16 | 2021-11-23 | 中国科学院空天信息创新研究院 | Airborne multi-channel circular track SAR moving target detection and estimation method |
CN113933804A (en) * | 2021-12-16 | 2022-01-14 | 中国科学院空天信息创新研究院 | Image domain azimuth multi-channel SAR error correction method |
CN114545411A (en) * | 2022-04-21 | 2022-05-27 | 南京信息工程大学 | Polar coordinate format multimode high-resolution SAR imaging method based on engineering realization |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN116679277A (en) * | 2023-07-26 | 2023-09-01 | 中国科学院空天信息创新研究院 | Minimum L based on time-frequency domain 1 Double-channel SAR multi-jammer positioning method based on norm |
CN116679277B (en) * | 2023-07-26 | 2023-10-17 | 中国科学院空天信息创新研究院 | Minimum L based on time-frequency domain 1 Double-channel SAR multi-jammer positioning method based on norm |
CN116718995B (en) * | 2023-08-09 | 2023-10-10 | 中国科学院空天信息创新研究院 | Azimuth multichannel SAR phase error correction method based on minimum spectrum difference |
Also Published As
Publication number | Publication date |
---|---|
CN116400310B (en) | 2023-07-28 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN116400310B (en) | Two-dimensional frequency domain azimuth multi-channel SAR error correction method | |
CN107741586B (en) | Satellite-borne Ka InSAR signal processing method based on DBF-TOPS weighting | |
EP3012658B1 (en) | Method and device for implementing sar imaging | |
CN109507666B (en) | ISAR sparse band imaging method based on off-network variational Bayesian algorithm | |
CN110632594B (en) | Long-wavelength spaceborne SAR imaging method | |
CN114545411B (en) | Polar coordinate format multimode high-resolution SAR imaging method based on engineering realization | |
CN110865346B (en) | Satellite-borne SAR time parameter calibration method based on direct positioning algorithm | |
CN113933804B (en) | Image domain azimuth multi-channel SAR error correction method | |
CN114509733B (en) | Multi-channel SAR interference suppression method based on joint cancellation | |
CN110133646B (en) | NLCS imaging-based multi-channel two-pulse clutter cancellation method for bistatic forward-looking SAR | |
CN109143235B (en) | Ground moving target detection method for double-base forward-looking synthetic aperture radar | |
CN113064161B (en) | Wave spectrometer cross spectrum calculation method based on double sub-pulse reconstruction | |
CN113376632B (en) | Large strabismus airborne SAR imaging method based on pretreatment and improved PFA | |
CN116718995B (en) | Azimuth multichannel SAR phase error correction method based on minimum spectrum difference | |
CN114488067A (en) | Data reconstruction method based on Staggered SAR system under low oversampling rate | |
CN114035191A (en) | CS imaging method used in ultra-high resolution mode of satellite-borne SAR | |
CN111638516B (en) | Terahertz frequency band SAR motion compensation algorithm based on double-frequency conjugate processing technology | |
CN113406624A (en) | High-resolution spaceborne SAR efficient time-frequency hybrid imaging method and system | |
CN114646958A (en) | Distributed small satellite beam-bunching MIMO-SAR ultrahigh resolution imaging method | |
CN112731389B (en) | Channel azimuth baseline error estimation method based on multi-channel complex image space characteristics | |
CN109975804B (en) | Multi-platform constellation SAR fusion coherent imaging method | |
CN115856788B (en) | Pitching multi-channel SAR interference suppression method based on channel cancellation | |
CN117518167B (en) | Wide SAR scanning mode system design method based on multichannel system | |
CN114791594B (en) | Ionized layer dispersion effect correction method for nonlinear frequency modulation signals | |
CN116482685B (en) | Self-adaptive DBF method based on beam domain phase center cross-correlation method |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
GR01 | Patent grant | ||
GR01 | Patent grant |