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2-D CS SAR imaging endures great computational complexity since it has to deal with a large measurement matrix when processing the raw data. The skew-view SAR signal features large range walk and small range curvature, which enable the raw data be processed in range and azimuth separately. In this paper, a two-dimension-separated compressive sensing method of is skew-view SAR presented. It can reduce...
Deceptive jamming, covering the true targets and producing false targets in the SAR image, has been widely applied in electronic warfare. To effectively suppress the deceptive jamming generated by detecting parameters of target echoes, this work proposes a novel anti-jamming approach. Firstly, the chirp signal with varying initial phase is predesigned and transmitted. Then, the random initial phases...
Simultaneous synthetic aperture radar (SAR) imaging and ground moving target indication (GMTI) is of great importance in remote sensing applications, but it is difficult to be implemented for existing methods due to the cross-interferences between stationary targets/clutter and moving targets. Generally, the imaged moving targets may be displaced in azimuth according to their radial velocities and...
To explore anisotropic information embedded among sub-aperture SAR images, we propose polarimetric sub-aperture singular value decomposition, where polarimetric and anisotropic features are simultaneously decomposed. The decomposed singular values and left singular vectors are equivalent to eigen-analysis-based polarimetric target decomposition, while the right singular vectors give the corresponding...
Clutter suppression is a key step for efficient detection of moving targets and accurate estimation of their parameters. Current clutter suppression approaches are available, in the case that clutter echoes of each channel are free of Doppler ambiguity. However, for multichannel high-resolution wide-swath (HRWS) synthetic aperture radar (SAR) system, the received echoes of each channel suffer Doppler...
A targets detection algorithm is proposed for maritime surveillance by single-channel SAR images. It foresees a preliminary prescreening step, carried out using an adaptive threshold algorithm, followed by a discrimination phase, performed by sub-look analysis. The latter discriminates the pixels detected by the former step in three classes, i.e. targets, sea, and azimuth ambiguity. The algorithm...
Ground based interferometric radar (GBIR) is a revolutionary advanced measurement technique for geoscience and engineering geodesy. It is powerful for temporally and spatially dense measurements of highly dynamic target with sub-millimetric accuracy, especially in man-made structures, e.g. buildings, towers, dams and bridges. In this case study, we use a real aperture radar system, the Gamma Portable...
Synthetic Aperture Radar (SAR) can take a fine radar image without relation to sunshine condition, so it is important to propose the display method that fulfills a user's demand. SAR provides some information with high-level process. To confirm both SAR image and the results of the high-level process simultaneously, the color display is effective. However, conventional method has the restriction of...
GF-3 is the Chinese Synthetic Aperture Radar (SAR) satellite mission with scientific and commercial applications, which will be launched in 2016. The ortho-rectification image combined with the DEM data can only be satisfied with the applications of the high resolution radar image, the data quantity with wide-breadth also put forward higher request to the automation processing. The Reverse-Range-Doppler...
In this paper, a new scheme is presented for ground moving target indication for multichannel synthetic aperture radar (SAR) systems using the asymmetric distribution of the spatial spectrum. Two feature images are generated via accumulating energy intensities of the positive and the negative spatial spectrum, respectively. In the two images, the stationary backgrounds have the same intensity while...
Sentinel-1 IWS interferometric time-series analysis (SBAS and PSI) is discussed and results over Mexico City, a mega-city subject to very substantial ground deformation, are presented. In the early steps the processing needs to be adapted to the organization of the data in sub-swaths and burst, and for the SLC co-registration an extremely accurate co-registration is required for interferometry, because...
This paper is focused on investigations of the improved detection of icebergs in open water using spectral analysis of polarimetric SAR data. The objectives of this study are to analyze the behavior of ice objects in open water using the sublook cross-correlation magnitude (SCM). It is shown that there is an improvement of iceberg-sea contrast when the SCM is used instead of multilook intensities...
Rapidly obtaining building damage information after the earthquake is vitally important to earthquake rescue and decision making. In this paper, we propose a new framework of building collapse extraction by combining polarimetric information and azimuth time-frequency analysis. The proposed framework consists of two main steps, i.e. open area removal and intact building identification. In the first...
Microwave metamaterial aperture imaging radar (MMAIR) is capable of generating high resolution images without using mechanical scanning or antenna arrays. In MMAIR, metamaterial elements are specifically embeded into a parallel plate waveguide, whose resonance frequencies vary among a wide bandwidth. Different radiation fields are gained by wide-band waveforms, and the scene information are measured...
It is the basis of realization ship recognition to accurately extract geometric parameters of the ship target in synthetic aperture radar (SAR) images. Due to the unique SAR imaging mechanism, speckle noise, azimuth ambiguity and side lobe effect seriously impact on geometric parameter estimation of the ship target. Therefore, a method is presented to extract geometric parameters of the ship based...
Synthetic aperture radar (SAR) images of the Earth's terrain surface contain the calculation of scattering coefficients and the simulation of backscattering echo, which are influenced by the terrain elevation and slope. In this study, we present a method of electromagnetic imaging for terrain surfaces based on airborne strip map synthetic aperture radar (SAR). First, the integral equation method was...
Along with increasingly intense desire to achieve super high-resolution images, synthetic aperture radar (SAR) is facing more severe technical challenges such as sampling, storage and transmission of massive data as well as high complexity of hardware. Compressive sensing (CS) theory, which utilizes the signal sparsity, can implement accurate image reconstruction from an extremely less amount of measurements...
The technique of multiple apertures in azimuth enables a wide swath synthetic aperture radar (SAR) with high azimuth resolution. In a traditional multi-channel SAR system, a reconstruction algorithm is built to recover the ambiguous Doppler spectrum caused by non-uniform sampling. However, if the system pulse repetition frequency (PRF) is near some specific values, singular points exist in the reconstruction...
This paper concerns the on-board data volume reduction for a single-platform multichannel Synthetic Aperture Radar (SAR) system. In such a system, the unambiguous Doppler spectrum reconstructed on-ground is enlarged at the cost of an increased amount of acquired data. Since the signals received by a multichannel SAR instrument are intrinsically correlated, such correlation can be exploited to represent...
Synchronous with RISAT-1 and RADARSAT-2 passes, corner reflectors (CR) were mounted for the evaluation of radiometric calibration of RISAT-1 compact polarimetric SAR data. Based on the CRs response on SLC images, RISAT-1 calibration constant, PSLR/ISLR, resolution, channel imbalance and cross-talk were analyzed and compared with that of product specifications. A difference of 0.5 to 1.5 dB is observed...
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