289 results about "Azimuth direction" patented technology

The invention relates to an X-band two-dimensional phased array radar which comprises a microstrip antenna transmitting and receiving antenna subarray, a power distribution / synthesis network, a digital T / R assembly, a frequency source, a wave control unit, a servo turntable, a terminal server and the like. A sub-array modular design is adopted for receiving and transmitting of a radar microstrip antenna, a 4 * 4 array is used as a basic sub-array unit for array expansion to achieve a 32 * 32 array, and the total number of channels is 1024. The detection capability of an original phased array weather radar on a local meteorological target can be improved, the problem that a traditional phased array radar is large in size and difficult to maintain is solved, electric scanning can be conducted in the azimuth direction and the pitching direction, meanwhile, the mechanical scanning capability is achieved, high-precision rainfall monitoring of the scene can be achieved through two-dimensional electric scanning of the vertical headspace, and the application range is wide. Therefore, the detection efficiency of the phased array radar is greatly improved, and real-time monitoring and scanning of a specified target are realized.

The invention relates to a single-channel moving target refocusing method and device based on a bunching mode, and the method comprises the steps: detecting a ground moving scene through a terahertz video radar, obtaining a single-channel echo signal, generating a two-dimensional image of the ground moving scene, and extracting a target image of a moving target from the two-dimensional image; the method comprises the following steps of: performing azimuth inverse Fourier transform on a target image to obtain a one-dimensional range image, performing secondary phase compensation by using an image displacement algorithm, and performing range envelope alignment on a compensated signal by using an adjacent cross-correlation algorithm of linear interpolation to correct a nonlinear error term so as to obtain a moving target refocusing image after the nonlinear error term is corrected. And the two-dimensional image is filled with the image to obtain a complete image. By adopting the method, the problem of image defocusing caused by micro-distance migration can be effectively solved.

The invention provides an SAR deception jamming method and device based on distance and azimuth two-dimensional modulation, and relates to the technical field of radar signal processing. The method comprises the following steps: determining an SAR signal intercepted by a jammer according to a transmitting signal of the SAR and an instantaneous slope distance from the jammer to the SAR; an interference signal is determined according to the instantaneous slant range difference between the jammer and the target, the distance offset in the distance direction, the distance offset in the azimuth direction and the SAR signal intercepted by the jammer, and the interference signal comprises an active cancellation signal and a distance and azimuth two-dimensional modulation phase; carrier frequency removal processing is carried out on the echo signal received by the SAR, the echo signal after carrier frequency removal is obtained, and the echo signal received by the SAR is the sum of the interference signal and the target echo signal; and imaging the echo signal after carrier frequency removal by using a distance Doppler algorithm to obtain an echo signal after imaging processing, so that diversified interference effects can be achieved.

The invention discloses a regional adjustable intermittent sampling interference method and system for an unmanned aerial vehicle SAR platform, and the method specifically comprises the steps: generating radar original data according to an intercepted unmanned aerial vehicle carried SAR signal; adopting a Bernoulli mapping sequence to carry out intermittent sampling on SAR signals of the unmanned aerial vehicle, and generating a randomly distributed non-uniform false target group; according to the generated intermittent sampling signal controlled by the Bernoulli mapping sequence, the distance direction and the azimuth direction of the SAR signal are interfered by using a distance direction frequency shift and false motion target characteristic modulation method, and a smart interference signal controlled by the Bernoulli mapping sequence after modulation is generated, so that the interference signal has a false motion characteristic; and after digital-to-analog conversion, low-pass filtering and up-conversion processing are carried out on the generated interference signal, the interference signal is sent by using a transmitting antenna, and interference on the SAR platform radar of the unmanned aerial vehicle is completed. The real moving target in the specific area is protected, and the method has the advantages of being simple, high in real-time performance and good in interference effect.

The invention discloses a secondary modulation interference signal generation method and device, a storage medium and equipment, and belongs to the technical field of radar countermeasure. The method comprises the following steps: a jammer processes a target SAR signal to obtain a digital SAR signal and calculates a signal parameter; generating a distance-direction phase modulation signal, a distance-direction sine function modulation signal, a distance-direction frequency shift modulation signal, an azimuth-direction phase modulation signal, an azimuth-direction sine function modulation signal and an azimuth-direction frequency shift modulation signal according to the signal parameters by combining a required interference type; according to the generated signals and the digital SAR signals, range direction modulation and azimuth direction modulation are completed, and finally digital interference signals are obtained; and converting the digital interference signal into an analog interference signal and forwarding the analog interference signal to the target SAR system, and generating different types of interference effects through imaging processing. According to the invention, nine different types of two-dimensional interference effects can be flexibly generated, and the central position of the interference result can be accurately controlled.

An environmental imaging method includes: A first device sends first indication information to a second device, where the first indication information indicates a first spatial location at which the second device is to send a measurement signal, and the first spatial location is evenly distributed in an azimuth direction and / or at an azimuth angle; the first device receives an echo signal, where the echo signal is a signal formed by reflecting, by a target, the measurement signal sent by the second device after the measurement signal arrives at the target; and the first device performs imaging on the target based on the echo signal. The method may be implemented in a system or an apparatus.

The invention discloses an unattended turntable servo control system. The method is applied to a two-dimensional rotary table, the rotary table comprises an azimuth rotating shaft and a pitching rotating shaft, and each rotating shaft is driven and controlled by a motor. The system comprises a control unit and a driving unit, the control unit is used for receiving the position information of the rotary table, the current information of each motor and a control instruction sent by external communication equipment, calculating a control signal required for driving each motor to a target position based on the received information, and sending the calculated control signal to the driving unit; and the driving unit generates a driving current based on the received control signal to drive the motors to rotate, so that each motor moves to a corresponding target position. According to the invention, free control of the rotary table under two degrees of freedom in the azimuth direction and the pitching direction can be autonomously realized.

The invention relates to a shadow-based ground moving target parameter estimation method, device and equipment, and the method comprises the steps: constructing a geometric model of terahertz video SAR (Synthetic Aperture Radar) moving target imaging in a bunching mode, and obtaining an echo mathematical model of a moving target based on the geometric model; after an echo signal obtained by detecting a ground motion scene by a terahertz video radar is expressed based on the echo mathematical model, the distance direction speed of a moving target is estimated through the relative offset of a moving target image and a shadow in the azimuth direction, and the distance direction speed of the moving target is calculated through the frequency broadening of the target image and the shadow in the azimuth direction. And estimating the azimuth direction speed of the moving target, and estimating the distance direction acceleration of the moving target according to the frequency modulation rate of the secondary phase through the compensation of the secondary phase. By adopting the method, accurate target parameter estimation can be obtained.

The invention provides a satellite-borne bistatic FMCW-SAR imaging method based on a non-stop-walk model, and relates to the technical field of signal processing, and the method comprises the steps: reading full-aperture echo data and imaging parameters which have been subjected to line frequency resolution processing, and carrying out the average segmentation of the full-aperture echo data in the azimuth direction, and obtaining a plurality of sub-aperture echo data; performing backward projection processing on all the sub-aperture echo data for realizing residual video phase term removal and range interpolation in a preset imaging grid to obtain a sub-aperture image corresponding to each piece of sub-aperture echo data; and carrying out compression, azimuth upsampling and decompression calculation on all the sub-aperture images, and carrying out coherence superposition calculation on the decompressed sub-aperture images to obtain a final imaging result. According to the scheme, high-precision focusing of echo data under a spaceborne bistatic FMCW-SAR system can be realized.

The invention relates to the field of information investigation and electronic countermeasure, in particular to a multi-element antenna array and a related system.The antenna array comprises a plurality of antenna array elements, a polygonal cylinder base, an antenna cover and a fixed bottom plate, and the input ends of the antenna array elements are connected with a radio frequency connector; the related system comprises an antenna array, a power supply and communication control module and a radio frequency module. The antenna array is used for solving the technical problems that an existing antenna array is narrow in frequency domain coverage, not wide enough in space domain coverage, large in weight and size and not integrated with the ultra-wideband azimuth direction finding function and the electronic interference function. According to the antenna array, the frequency coverage is 2-18 GHz, the airspace coverage is 360 degrees, the lightweight design is realized, and the antenna array integrates the functions of omnibearing direction finding and electronic interference; spatial multipath investigation signals are received to carry out combined amplitude comparison direction finding, characteristics and threat levels of the investigation signals are calculated and confirmed through an algorithm, and then investigation tracking and electronic interference tasks are carried out on a threat target in a specified direction according to the orientation of the threat target.

The invention provides a multifunctional C-band dual-polarization phased-array antenna system, and relates to the technical field of wireless signals. The system comprises an antenna array surface, a digital beam forming module, a monitoring network and a frequency source, wherein the antenna array surface adopts an upper, lower, left and right separated antenna structure, and the whole antenna system is composed of four independent sub-antennas; the antenna can generate sum and difference beams in the azimuth direction and the pitching direction, so that target monopulse tracking can be carried out while meteorological detection is carried out, and the device has the characteristic of multiple functions; a row of linear array of the antenna is divided into two sections which are symmetrical left and right, the length of a feeder line between the digital T / R assembly and the antenna unit is reduced, the stage number of a power divider is reduced by one stage, the feeder line loss is reduced, and the detection capability of the radar is improved. In addition, a two-stage fitting Taylor weighting method is also adopted to realize the low side lobe performance of the azimuth plane, so that the dual polarization consistency of the antenna is good in a broadband range, and the side lobe is lower than-35dB.

A bottom hole assembly includes a downhole conveyance that is extendable from a terranean surface, through a wellbore, and to a subterranean formation; and a perforating tool configured to couple to the downhole conveyance and create a perforation cluster in the subterranean formation. The perforation cluster includes perforations arranged along a longitudinal direction of the wellbore. The perforations includes one or more first perforations extending along a first azimuthal direction, one or more second perforations extending along a second azimuthal direction at a first offset angle with respective to the first azimuthal direction, and one or more third perforations extending along a third azimuthal direction at a second offset angle with respective to the first azimuthal direction. The one or more second perforations and the one or more third perforations are alternative with each other along the longitudinal direction of the wellbore.

Provided is an ultrasonic diagnostic device capable of changing the sound velocity value in a local region. An ultrasound diagnostic device (100) of the present disclosure generates an ultrasound image (144) on the basis of an echo signal (142) from a subject (BD). An ultrasound diagnostic device (100) is provided with: an ultrasound probe (110) that receives an echo signal (142); an interface capable of specifying position information of a local region of the ultrasound image by an operator; and a signal processing means (120) that, when reconstructing the echo signal (142) and reconstructing the ultrasonic image (144), changes the sound velocity value of the local region so as to differ from the sound velocity value of a region other than the local region on the basis of the position information. The local region is local in both the azimuth direction (X) and the depth direction (Y).

The invention discloses a one-dimensional error analysis method, system and device for a synthetic aperture sonar imaging method, and relates to the technical field of image processing, and the one-dimensional error analysis method comprises the steps: calculating a joint directivity function of a transmitting array element and a receiving array element according to the directivity functions of the transmitting array element and the receiving array element, and determining the beam width of a sonar system; according to the farthest imaging distance and the beam width of the sonar system, calculating the coordinates of the target to be set in the azimuth direction in the imaging area; according to the geometrical relationship, calculating the distance error between the accurate instantaneous two-way slant distance between different positions in the sonar azimuth direction and the target and the approximate slant distance of the to-be-evaluated imaging method; determining the minimum number of targets to be set and coordinates in the distance direction in the imaging area, and determining a receiving array element of a distance error to be inspected; and calculating the distance error between the accurate instantaneous two-way slant distance and the approximate slant distance of the to-be-evaluated imaging method, so that the method can quickly evaluate the advantages and disadvantages of the sonar imaging method.

The invention belongs to the technical field of image processing, and discloses a three-dimensional radar sub-aperture imaging deformation monitoring device and method, and the device comprises a radar which is used for collecting echo signals passing through a preset position, processing the echo signals according to frequency mixing and analog-to-digital conversion, obtaining a three-dimensional echo matrix, and outputting the three-dimensional echo matrix; the three-dimensional echo matrix and a sampling ending signal are sent to a motion compensation module; the motion compensation module is used for resampling the azimuth direction of the three-dimensional echo matrix by adopting an interpolation algorithm; the distance matching filtering module is used for performing pulse compression on the distance direction of the three-dimensional echo matrix; the migration correction module is used for carrying out migration correction on the distance direction of the three-dimensional echo matrix after pulse compression; the sub-aperture imaging module is used for calculating a three-dimensional echo matrix after migration correction according to a sub-aperture imaging algorithm; and the deformation monitoring module is used for performing interference difference processing on the three-dimensional complex image to obtain deformation data. The imaging quality and the deformation monitoring precision can be improved.

The invention discloses a receiving and transmitting combined synthetic aperture sonar distance stack imaging method, system and device, and relates to the technical field of image processing, and the distance stack imaging method comprises the steps: calculating a two-way slant range course for a reference point target in an imaging region; calculating a reference echo signal of a reference point target based on the two-way slant range course and the parameters of the transmitted signal, and performing two-dimensional frequency domain transformation to obtain a reference frequency spectrum; two-dimensional frequency domain transformation is carried out on an original actually-measured echo signal of the receiving and transmitting combined synthetic aperture sonar to obtain an echo frequency spectrum, and conjugate multiplication is carried out on the echo frequency spectrum and a reference frequency spectrum in a two-dimensional frequency domain; coherent accumulation is carried out in a range direction frequency domain according to a conjugate multiplication result, and inverse Fourier transform is carried out in an azimuth direction; and processing the pixels at other distances in the imaging area according to the steps to obtain processing results of all the pixels in the whole imaging area, and carrying out carrier frequency removal on the basis to obtain an imaging result of the whole imaging area.

The invention relates to the technical field of radar imaging, and discloses a synthetic aperture radar forward oblique imaging polar coordinate imaging algorithm, which comprises the following steps: acquiring an electromagnetic signal reflected when a radar wave reaches a detection target and flight path data of the radar wave, performing data preprocessing, and establishing echo data; and converting a rectangular coordinate system of the echo data into a polar coordinate system, and carrying out gridding processing. And removing the Doppler effect in the echo data after gridding processing based on a distance Doppler algorithm, and determining the azimuth of the echo data based on polar coordinate fast Fourier transform. And based on a pre-configured view angle, dividing the echo data after the Doppler effect is removed into a plurality of sub-regions for block processing, and reconstructing an image to be generated. And performing image filtering enhancement and artifact elimination on the to-be-generated image, and converting the to-be-generated image into a standard image format for output. According to the invention, through signal processing and image reconstruction technologies, the accuracy and reliability of radar imaging can be effectively improved.

A satellite constellation (100) includes a plurality of artificial satellites (111 to 116) that number a multiple of 6. Each of the plurality of artificial satellites orbits in an inclined circular orbit a plurality of times a day. Normals to a plurality of orbital planes corresponding to the plurality of artificial satellites are shifted by an equal angle from each other in an azimuth direction. The plurality of orbital planes make up one or more orbital plane sets each consisting of six orbital planes. Timings at which the six artificial satellites orbit on the six orbital planes of each orbital plane set are synchronized with each other.

The invention discloses an SAR sea peak suppression imaging method and system based on STFT, and belongs to the technical field of synthetic aperture radar signal processing. The method comprises the following steps: performing range pulse compression on received original SAR echo data; taking data of one range gate in the range pulse compression result, and performing short-time Fourier transform along the azimuth direction; calculating the correlation between the short-time Fourier spectrum energy statistical distribution with the sea peak interference and the short-time Fourier spectrum energy statistical distribution without the sea peak interference, and obtaining a threshold value for suppressing a sea peak echo signal; suppressing the time-frequency point of which the short-time Fourier spectrum energy is greater than the sea peak echo signal suppression threshold value, and obtaining effective time-frequency domain data; and carrying out inverse short-time Fourier transform on the effective time-frequency domain data to obtain reconstructed SAR echo data and realize SAR sea peak suppression imaging. According to the method, HH and VV dual-polarization data does not need to be acquired at the same time, single-polarization data can be processed, the calculated amount is simplified, and SAR sea peak echo signals can be effectively suppressed.

The invention relates to the technical field of image data processing, and discloses a long-time-sequence glacier flow velocity monitoring method, which comprises the following steps of: acquiring a glacier SAR (Synthetic Aperture Radar) image sequence and preprocessing to generate a plurality of multi-view SAR images; setting a time baseline threshold value, performing image pair combination on all the multi-view SAR images, performing offset estimation, and respectively generating a plurality of offset sequences in azimuth and distance directions; constructing a nonlinear glacier flow velocity model based on seasonal components, optimizing all offset sequences, generating an optimized offset sequence, calculating a glacier surface average flow velocity field, and generating a glacier flow velocity direction matrix in combination with second glacier cataloguing data; taking the optimized offset sequence as an observed quantity, setting a glacier flow direction as a constraint condition, and carrying out iterative solution on displacement distribution corresponding to the imaging moment of each multi-view SAR image by adopting a least square method to obtain optimal displacement distribution corresponding to the imaging moment of each multi-view SAR image; according to the method, the reliability and precision of glacier flow velocity calculation are improved.

The invention discloses a high-resolution SAR deception jamming signal rapid generation method and device, and belongs to the technical field of radar countermeasure. The method comprises the following steps: intercepting an SAR signal and measuring parameters of the SAR signal; obtaining a deception jamming template image, and carrying out edge optimization processing; performing two-dimensional partitioning on the template in the distance direction and the azimuth direction to obtain a plurality of sub-templates; calculating a phase compensation function for the central point of each sub-template, and carrying out phase optimization; the optimized sub-templates are superposed, and a high-quality product modulation matrix is generated; and multiplying the matrix by an intercepted SAR signal, and transmitting after digital-to-analog conversion and up-conversion to form a deception jamming signal. According to the method, through block phase compensation and template edge optimization, the imaging quality and concealment of the deception jamming image under the high-resolution SAR are remarkably improved, meanwhile, low calculation complexity is kept, and the method is suitable for satellite-borne and airborne SAR systems.

The invention discloses a method for realizing elliptic cone scanning by a communication-in-moving antenna. The method comprises the following steps: determining the value of a scanning position point number parameter N; determining the value of the maximum scanning offset angle delta A in the azimuth angle direction and the value of the maximum scanning offset angle delta E in the pitch angle direction; determining values of an expected azimuth angle alpha 0 and an expected pitch angle beta 0 of the current antenna; setting a scanning counter i; when i is less than 4N, calculating a parameter theta i, calculating a scanning offset angle delta i, calculating a scanning track beta i of a pitch angle, and calculating a scanning track alpha i of an azimuth angle; the pitch angle of the antenna is controlled to rotate to a new position beta i, and the azimuth angle of the antenna is controlled to rotate to a new position alpha i; and updating the scanning counter i, i = mod (i + 1, 4N), and returning to execute. The method not only can realize elliptic cone scanning, but also can realize cone scanning, and can effectively solve the problem that the average receiving level is reduced when the communication-in-moving antenna of which the cross section of the beam main lobe is elliptic performs cone scanning.

The invention discloses an SAR image self-focusing distortion correction method and device, and belongs to the technical field of synthetic aperture radars. The method comprises the following steps: carrying out distance blocking and orientation sub-aperture division on a defocused SAR image, selecting a sample, and carrying out orientation decompression to a phase historical domain; performing azimuth dechirp processing on the sub-aperture data in each distance sub-block, and estimating a phase error through a standard PGA algorithm; after splicing sub-aperture phase errors and removing an overall linear phase, performing phase compensation and azimuth compression to obtain a focused image; and for azimuth distortion caused by residual linear phase of the compensated image, extracting a phase error linear term coefficient through a sliding window, deducing an azimuth shift distance in combination with Fourier transform time shift characteristics, and finally performing shift correction by adopting sinc interpolation. According to the method, the image focusing quality is improved, and meanwhile, the ground feature continuity and the image resolution are kept.

The invention relates to a satellite-borne SAR antenna pointing deviation in-orbit identification and satellite attitude compensation method, which comprises the following steps: determining a satellite attitude angle imaged according to a nominal beam according to a nominal installation matrix and an imaging lower visual angle, and controlling a satellite to complete SAR load positive side view strip imaging according to the satellite attitude angle to obtain image data; determining a distance deviation distance between a sheet center and an expected sheet center, a center Doppler frequency deviation value of the sheet center, and center Doppler frequency deviation values of a sheet far end and a sheet near end according to the image data; calculating a distance direction deviation angle, an azimuth direction deviation angle and a torsion deviation angle of the actual wave beam relative to the nominal wave beam; and calculating an antenna deviation matrix, updating the nominal installation matrix, and determining the satellite attitude according to a new installation matrix during next imaging. According to the method, the satellite-borne SAR antenna pointing deviation can be effectively eliminated, the SAR image quality is improved, and the on-orbit application efficiency of an SAR satellite is improved.

The invention belongs to the technical field of unmanned aerial vehicle detection countering, and discloses a spectrum identification and direction finding system and method for a small unmanned aerial vehicle. The system comprises an antenna array element, a radio frequency switch, a data acquisition card, a CPU processing mainboard and an upper computer. According to the algorithm of the CPU processing mainboard, for unmanned aerial vehicle model identification and azimuth direction finding, based on a neural network algorithm model and an array structure model of a uniform circular array, rapid and accurate classification of different radio frequency signal types is realized through time-frequency diagram analysis, recessive advanced features of signals can be extracted from large-scale data, and a result can be directly output. And the unmanned aerial vehicle model is quickly identified. A DOA estimation algorithm based on deep learning is adopted, a DOA estimation value can be quickly given through an algorithm model based on covariance matrix decomposition, a final result is obtained, and an azimuth angle can be accurately given. The defect that a traditional algorithm is sensitive to the multi-path effect is overcome, and high-precision direction estimation can be achieved.

A method of operating a Synthetic Aperture Radar ‘SAR’ to acquire image data of a swath comprising one or more subswath(s) is provided, wherein the SAR is carried on a platform moving along a flight direction and a radiated beam is directed towards the swath, the method comprising: electronically steering the beam in azimuth direction along one subswath for each burst; and mechanically steering the beam in a direction opposite to the flight direction during each burst. The method allows to obtain an improved swath to resolution ratio.

The invention provides a method for obtaining a three-dimensional body through two-dimensional seismic reflection data gridding, and belongs to the field of seismic data processing. Through a technical means of constructing a virtual grid through rotation, a two-dimensional measuring line is converted into a three-dimensional data body which is uniformly distributed in space, and subsequent data processing is not limited to one direction any more. Specifically, latitude and longitude coordinates of each discrete reflection data are obtained and converted into UTM projection rectangular coordinate values, and coordinate values of a longitude minimum point are determined; calculating the optimal azimuth angle of the grid according to the plane distribution characteristics of the discrete points, and determining the grid spacing along the azimuth angle direction and the vertical azimuth angle direction; the grid is rotated to the three-dimensional grid direction, the coordinates of the point with the minimum longitude value after rotation are extended outwards by a half grid interval, and the coordinates of the point serve as base points of the grid; all the coordinate points are rotated in the same way, data falling into the same grid are superposed, then the coordinate number of each point in the grid is calculated, and a three-dimensional data volume is obtained accordingly.

The invention discloses a block self-focusing ISAR (inverse synthetic aperture radar) imaging method and system based on an FPGA (field programmable gate array), and the method comprises the steps: obtaining ISAR echo data, and sequentially carrying out the preprocessing and global self-focusing processing, thereby obtaining a global self-focusing correction matrix; dividing the global self-focusing correction matrix into a plurality of sub-matrix blocks in a sliding window partitioning manner; performing minimum entropy self-focusing processing on each sub-matrix block to generate an optimized sub-matrix block; performing fast Fourier transform on the optimized sub-matrix blocks in the azimuth direction to generate two-dimensional image data; determining an offset according to an overlapping region of the adjacent sub-matrix blocks, performing cyclic shift processing on the two-dimensional image data corresponding to the current optimized sub-matrix block in the azimuth direction based on the offset, and aligning the two-dimensional image data corresponding to the previous adjacent optimized sub-matrix block; and outputting the aligned corrected two-dimensional image data as an ISAR imaging result. According to the invention, the azimuth focusing performance is improved, and the overall imaging quality is obviously improved.

The present invention provides a high-speed ultra-short-range SAR local BP fast imaging method, which includes constructing a geometric model of a two-dimensional imaging scene and deriving the target scattering point echo signal received by the radar based on the model. The method also includes the following steps: pixel segmentation of the ultra-short-range SAR application scene based on a polar coordinate system; performing frequency modulation processing on the echo signal to obtain the distance R of all targets to the radar when the slow time is zero in the frequency domain. n ; The distance is R n , n∈{1…N}, azimuth direction from θ0 to θ m For a certain pixel in the range, the echo signal amplitude is coherently accumulated in the slow time domain; all azimuth pixels are traversed to obtain the range R n The imaging result is obtained by looping through all target distances using the method in step 3, and obtaining a frame image of the entire scene. The present invention proposes a local BP imaging method based on polar coordinates, which uses the target distance obtained by Fourier transform to narrow the imaging range.

The invention discloses a side lobe suppression method for an SAR image, and the method comprises the steps: obtaining an imaging result containing a high side lobe through a CS algorithm; secondly, re-arranging a scene only containing one point target with the intensity of 1, performing echo simulation on the newly arranged scene and imaging based on the CS algorithm, and obtaining an imaging result of the point target under the CS algorithm as a convolution kernel; and finally, a real scene image is obtained through Lucy-Richardson-based time domain filtering deconvolution. According to the invention, the sidelobe interference in the orientation in the imaging process can be inhibited, the robustness and universality of the imaging method are improved, and the imaging quality is further improved.