As for the problem of too long training time convolution neural network (CNN), this paper proposes a fast method CNN in SAR automatic target recognition (ATR). The is divided into two parts: one that contains all layers and sub-sampling considered as convolutional auto-encoder (CAE) unsupervised to extract high-level features; other fully connected regarded shallow (SNN) work classifier. experiment based on MSATR database shows proposed can tremendously reduce with little loss rate.

The Global Navigation Satellite System (GNSS)-based passive bistatic radar (PBR) which uses the GNSS signal as illuminators of opportunity is studied for moving target detection (MTD). GNSS-based PBR has many advantages due to removal transmitting device; however, its fundamental limitation low power density signal. Therefore, integration time should be sufficiently long obtain a promising maximum detectable range. On other hand, limited by range migration and Doppler echo caused motion. In...

Squint spaceborne synthetic aperture radar (SAR) can significantly improve the ground observation performance of platform sensor through flexible beam pointing; however, it is still challenging for squint sliding spotlight SAR data focusing since significant range cell migration (RCM) and azimuth coupling (RAC) caused by angles. Whereas linear walk correction (LRWC) deal with these problems, traditional chirp scaling (CS) algorithm cannot adapt to signal model after LRWC operation,...

Synthetic Aperture Radar (SAR) is a well-established and powerful imaging technique for acquiring high-spatial-resolution images of the Earth’s surface. With development beam steering techniques, sliding spotlight staring modes have been employed to support applications. In addition this strengthened wide-swath capability, high-temporal-resolution (short repeat-observation interval) represents key capability numerous However, conventional SAR systems are limited in that same patch can only...

Global Navigation Satellite System Reflectometry (GNSS-R) based Bi-static Synthetic Aperture Radar (BSAR) is becoming more and important in remote sensing, given its low power, mass, cost, real-time global coverage capability. Due to complex configuration, the imaging for GNSS-R BSAR usually on Back-Projection Algorithm (BPA), which very time consuming. In this paper, an efficient general algorithm presented. A Two Step Range Cell Migration (TSRCM) correction firstly applied. The first step...

Scanning synthetic aperture radar (ScanSAR) mode is widely used in Earth observation because of its capability acquiring wide-swath images with moderate resolution. However, due to the operation mechanism ScanSAR mode, acquired often suffer from scalloping problem, resulting significant deterioration image quality. In this article, a novel suppression method proposed for based on modified Kalman filter preprocessing. First, an model built analyze effect caused by scalloping. Then, estimate...

The high-squint airborne Synthetic Aperture Radar (SAR) has the ability to detect target area flexibly, and detection swath is significantly increased compared with side-looking SAR system. Therefore, it of great significance carry out research on high-precision imaging methods for SAR. However, echoes have large Range Cell Migration (RCM), resulting in severe range–azimuth coupling strong spatial variation. In this paper, a Modified Doppler Algorithm (MRDA) proposed cope these effects...

In this study, we introduce a novel self-supervised learning adapter based on permutated image restoration (PIR) for effectively transferring pretrained weights from natural images to remote sensing object detection tasks. The adapter's unique methodology encompasses three-phase process: segmenting and permuting blocks, estimating permutation matrices sequence reconstruction, applying specialized loss functions accurate block positioning. use of our approach results in the maintenance...

Spaceborne Synthetic Aperture Radar (SAR) is a well-established and powerful imaging technology that can provide high-resolution images of the Earth's surface on global scale. For future SAR systems, one key capabilities to acquire with both wide-swath. In parallel evolution sensors, more precise range models, effective algorithms are required. Due significant azimuth-variance echo signal in High-Resolution Wide-Swath (HRWS) SAR, two challenges have been faced conventional algorithms. The...

Recently, electromagnetic (EM) vortex with orbital angular momentum (OAM) attracts more attention in radar imaging fields, which needs a variety of OAM modes. However, most them are based on motion relative static. In this paper, we propose novel SAR method OAM. The geometry model synthetic aperture (SAR) is utilized for EM and the echo signal deduced correspondingly, including additional phase items produced by waves. Then algorithm aiming at Chirp-Scaling proposed. Simulation results...

Recently, with the development of deep learning and springing up synthetic aperture radar (SAR) images, SAR maritime target detection based on convolutional neural network (CNN) has become a hot issue. However, most related work is realized general purpose hardware like CPU or GPU, which energy consuming, non-real-time unable to be deployed embedded devices. Aiming at this problem, paper proposes method deploy model an device employs custom artificial intelligence streaming architecture...

To increase the global convergence and processing efficiency of particle swarm optimization (PSO) applied in adaptive joint time-frequency, this study an improved PSO is proposed to refocus high-resolution SAR images complex moving vessels high sea states. According characteristics high-order multi-component polynomial phase signal, algorithm provides parallel co-evolution methods by setting different permissions sub-population sharing its search information. As a result, multiple components...

This paper reviews the novel azimuthal multi-angle spaceborne Synthetic Aperture Radar (SAR) technique. First, development status and trend of SAR satellites are analyzed, their observation capacities compared considering different aspects. Furthermore, imaging modes presented based on application requirements, mechanism is analyzed in detail. Moreover, advantages system for obtaining full scattering information, geometry motion information ground targets analyzed. Detailed conclusions...

In this paper, a novel algorithm of geometric correction for spotlight and sliding SAR is presented. Synthetic Aperture Radar (SAR), which independently weather light conditions, well-established imaging technique remote sensing [1]. With the increasing demands higher resolution, modes have been The key requirement understanding image to map location pixels accurately, requires more accurate assure quality products [2]. 1982, Range-Doppler method, effective stripmap SAR, has presented by...

The F-SCAN principle is a better alternative to the scan-on-receive technique (SCORE) based on digital beamforming (DBF), which can avoid low gain caused by conventional broad beam in case of wide swath. In SAR, pencil scans entire target area from far near, providing high energy independent position and ensuring range ambiguity-to-signal ratio (RASR). Moreover, echo compression be achieved via appropriate system parameter configuration, significantly shortening receive window reducing...

In recent years, electromagnetic vortex waves carrying orbital angular momentum (OAM) arouse extensive attention in remote sensing imaging fields. However, most of the researches concentrate on staring mode, where radar is motionless relative to targets. We establish a novel system operation mode based principle synthetic aperture (SAR). The echo model upon this established and new method modified from back-projection (BP) algorithm deduced. Simulation image evaluation results demonstrate...

Azimuth ambiguities in spaceborne synthetic aperture radar (SAR) will introduce multiple similar targets which affect image quality seriously. Also, it directly the correct rate of SAR target detection. Many suppression methods were put forward, made good results. But most need manually mark azimuth ambiguities, is obviously not suitable when processing huge amount images. For on sea, this paper puts forward a new method to detect and automatically high resolution images using single shot...

High-Resolution Wide-Swath (HRWS) is an important development direction of space-borne Synthetic Aperture Radar (SAR). The two-dimensional spatial variation the Doppler parameters most significant characteristic sliding spotlight SAR system under requirements HRWS. Therefore, compensation challenging problem faced in imaging HRWS situations. compensatory approach then proposed to address this paper. distribution for data working mode firstly analyzed, based on which a Spatial-Variant...

With the increasing demands for higher resolution and wider swath in many applications of Synthetic Aperture Radar (SAR), sliding spotlight mode has been presented. Here antenna pattern is steered towards a fixed point to increase synthetic aperture length consequently better resolution. Currently, image processing algorithms are almost based on equivalent slant range model (ESRM). A great challenge be faced signal mode. The ESRM, which used processing, may cause Doppler parameter mismatch...

AbstractTo overcome the inherent conflict between azimuth resolution and wide swath in conventional synthetic aperture radar (SAR) systems, concept of raster scan SAR (RS-SAR) is proposed this letter, where observation realized by slant beam scanning effective reception echo data achieved varying pulse repetition frequency. Details RS-SAR are provided, its significantly improved performance demonstrated an example system based on several derived key indicators.

High resolution wide Swath (HRWS) is one of the major development directions synthetic aperture radar (SAR).However, high in azimuth direction and range swath impose contradicting requirements on system design, conventional SAR systems cannot meet these rising demands.The compressive sensing (CS) theory put forward recent years provides a way to resolve contradiction.In CS framework, signal can be reconstructed with sampling rate below Nyquist frequency, which means that acquired processed...