共查询到20条相似文献,搜索用时 125 毫秒
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An improved two-channel Synthetic Aperture Radar Ground Moving Target Indication (SAR-GMTI) method based on eigen-decomposition
of the covariance matrix is investigated. Based on the joint Probability Density Function (PDF) of the Along-Track Interferometric
(ATI) phase and the similarity between the two SAR complex images, a novel ellipse detector is presented and is applied to
the indication of ground moving targets. We derive its statistics and analyze the performance of detection process in detail.
Compared with the approach using the ATI phase, the ellipse detector has a better performance of detection in homogenous clutter.
Numerical experiments on simulated data are presented to validate the improved performance of the ellipse detector with respect
to the ATI phase approach. Finally, the detection capability of the proposed method is demonstrated by measured SAR data. 相似文献
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Application of TerraSAR-X Data for Emergent Oil-Spill Monitoring 总被引:1,自引:0,他引:1
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Gabele M. Brautigam B. Schulze D. Steinbrecher U. Tous-Ramon N. Younis M. 《Geoscience and Remote Sensing, IEEE Transactions on》2010,48(2):795-806
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TerraSAR-X SAR Processing and Products 总被引:4,自引:0,他引:4
Breit H. Fritz T. Balss U. Lachaise M. Niedermeier A. Vonavka M. 《Geoscience and Remote Sensing, IEEE Transactions on》2010,48(2):727-740
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Statistical analysis of multilook SAR interferograms for CFAR detection of ground moving targets 总被引:8,自引:0,他引:8
This paper examines the statistics of the phase and magnitude of multilook synthetic aperture radar (SAR) interferograms toward deployment of along-track interferometry (ATI) for slow ground moving-target indication (GMTI). While the known probability density function (pdf) of the interferogram's phase (derived under the assumption of Gaussian backscatter) is shown to agree almost perfectly for a wide variety of backscatter conditions, the corresponding magnitude's pdf tends to deviate strongly in most cases. Motivated by this discrepancy, a novel distribution is derived for the interferogram's magnitude. This pdf, called the polynomial or p-distribution, matches the real data much more accurately, particularly for heterogeneous composite terrain. For extremely heterogeneous terrain, such as urban areas, both pdfs for interferometric phase and magnitude fail and are extended. Based on these statistics, a completely automatic detection scheme with constant false-alarm rates (CFARs) for slow moving targets is proposed. All involved parameters required to determine the detection thresholds are estimated from the sample data. It is demonstrated, on the basis of experimental airborne SAR data, that this detector is capable of detecting slow moving vehicles within severe ground clutter. 相似文献
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利用样本协方差矩阵特征值分解实现双通道SAR动目标检测 总被引:1,自引:1,他引:0
该文针对机载双通道SAR-GMTI系统及实测数据,提出一种新的地面慢动目标检测方法。该方法基于双通道样本协方差矩阵特征值分解,将杂波第2特征值和干涉相位联合统计特性的研究结果用于慢动目标检测,即根据给定的恒虚警概率确定一条联合分布的第2特征值干涉相位等高线作为门限检测曲线,同时结合第2特征值、干涉相位门限预处理,实现地面慢动目标的精确检测。实测数据实验结果表明:该方法不但扩大了慢动目标的可检测速度范围,同时还降低了系统的虚警概率。 相似文献
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Schwerdt M. Brautigam B. Bachmann M. Doring B. Schrank D. Hueso Gonzalez J. 《Geoscience and Remote Sensing, IEEE Transactions on》2010,48(2):677-689
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Theoretical Evaluation of Several Possible Along-Track InSAR Modes of TerraSAR-X for Ocean Current Measurements 总被引:1,自引:0,他引:1
The German satellite TerraSAR-X, scheduled for launch in late 2006, will permit high-resolution ocean current measurements by along-track interferometric SAR (along-track InSAR) in various experimental modes of operation, using different sections of its X-band SAR antenna array with a total length of 4.8 m as individual receive antennas. Depending on antenna and receive-chain settings, effective InSAR time lags of about 0.17 to 0.29 ms can be realized in combination with different noise levels, single-look resolutions, swath widths, and incidence angles. We give an overview of the characteristics of the possible InSAR modes and evaluate their suitability for current measurements on the basis of simulated data products. Our results indicate that the quality of interferometric stripmap data from TerraSAR-X will be clearly superior to the quality of the existing data acquired over the Dutch coast during the Shuttle Radar Topography Mission; accurate current retrievals can be expected at effective spatial resolutions on the order of 500 m. However, in modes using a multiplexed single receive chain, the effective swath width of stripmap data will be limited to only 15 km, while dual receive-chain operation offers a swath width of 30 km for stripmap data and promises a reasonable data quality even for ScanSAR data with a maximum swath width of 100 km. Finally, we consider fundamental relations between along-track baseline, instrument noise, and resulting InSAR phase noise to discuss the potential for current measuring performance improvements of TerraSAR-X follow-on satellites 相似文献
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对ATI技术进行改进,提出了一种机栽双通道SAR加权ATI地面慢速运动目标检测方法。该方法将DPCA技术和ATI技术的优点结合起来,利用DPCA技术得到加权值对ATI干涉结果进行加权处理,提出了一种新的动目标检测方法。计算机仿真结果表明,该改进方法与ATI方法相比能够有效减少虚假目标的数目,并能够检测到弱目标;与DPCA方法相比,它能够检测到DPCA方法由于对消过大而无法检测到的速度更慢的目标。 相似文献
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子带子孔径ATI地面运动目标检测及参数估计方法 总被引:1,自引:1,他引:0
该文提出了一种新的基于子带子孔径图像序列的顺轨干涉(ATI)地面运动目标检测方法。该方法利用超宽带合成孔径雷达(UWB SAR)的大带宽大波束角和低频特性,生成了对应不同中心频率和视角的多幅子带子孔径顺轨干涉图,并联合运动目标的多频多子孔径干涉相位进行地面运动目标检测和参数估计。该方法相比传统的ATI方法的优点在于:在检测方面,消除了盲速,既能检测具有距离向速度的目标,又能检测具有方位向速度的目标;在速度估计方面,能无模糊地同时估计出目标的距离向速度和方位向速度。基于UWB SAR半实测回波的实验验证了该方法的有效性。 相似文献
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基于ATI的双通道UWB SAR运动目标检测和距离向速度估计 总被引:1,自引:0,他引:1
本文对基于ATI的双通道UWB SAR运动目标检测和距离向速度估计算法进行了研究.针对运动目标易在UWB SAR图像上散焦的特点,本文对运动目标在双通道UWB SAR图像上散焦像轨迹之间的位置关系及干涉相位进行了分析;针对ATI算法运动目标检测中的盲速现象和距离向速度估计时的距离向速度模糊现象,本文根据UWB SAR大相对带宽的特点,提出了一种多频子带ATI方法消除盲速区、解除距离向速度模糊,该方法只需两部接收天线,相比多基线方法可大大节省硬件成本.基于半实测数据的实验证明了本文所提理论正确性和算法的有效性. 相似文献
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Maurer E. Mrowka F. Braun A. Geyer M. P. Lenzen C. Wasser Y. Wickler M. 《Geoscience and Remote Sensing, IEEE Transactions on》2010,48(2):642-648
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Meysam Mohammadi Alimorad Mahmoudi 《Multidimensional Systems and Signal Processing》2017,28(4):1367-1391
Accessibility of a fast and accurate multichannel synthetic aperture radar raw data generator of stationary clutter and moving targets has high importance, especially in the application of ground moving target indication. In this paper, a fast four-stage algorithm for generating the raw data of each channel stationary clutter and moving targets, has been proposed respectively in the frequency and the hybrid time–frequency domain. Using this simulator, in different conditions in terms of target motion speed, acceleration and direction, for each of the channels, after generating the raw data, its final image has been extracted by the range-Doppler algorithm. Then, using clutter suppression techniques such as DPCA, ATI and hybrid DPCA–ATI, the multichannel SAR final image has been obtained in ideal and nonideal conditions. Finally, the obtained images of the first channel have been studied using the extracted formulas for predicting the effects of target motion parameters on the SAR images as well as analyzing the multichannel SAR final image. The results show that the proposed algorithm for generating the raw data of each channel stationary clutter and moving targets has better performance in terms of speed and accuracy than the other existing simulators and the proposed multichannel SAR simulation method has high quality. 相似文献
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Moran M.L. Greenfield R.J. 《Geoscience and Remote Sensing, IEEE Transactions on》2008,46(7):2038-2043
We present a simple passive technique for estimating the acoustic-to-seismic signal coupling ratio (SAR) in the ground using noise produced by moving vehicles. The seismic signal received on a geophone contains some energy that has propagated as seismic waves and some energy that couples from acoustic waves to seismic waves in the vicinity of the geophone. We use the frequency-domain coherence between the microphone and geophone signals to determine when the seismic signal is predominantly due to acoustic-to-seismic wave coupling. In frequency bands where the microphone and geophone coherence is above 0.8, the ratio of the seismic ground particle velocity to sound pressure-SAR-can be determined with less than 2 dB of error. The method is applied to data from a summer experiment with grass ground cover and at two winter experiments with snow-covered ground. At 100 Hz, the summer analysis yields a SAR value of 1.0 times 10-5 [(m/s)/Pa]. In addition, at 100 Hz, the two winter tests yield SAR between 0.1 times 10-5 and 1.0 times 10-5 [(m/s)/Pa]. In the later winter result, our vehicle-derived SAR estimate is shown to be in excellent agreement with SAR estimates obtained from blank pistol shots. Through the opportunistic exploitation background noise sources, our approach opens the possibility for automatic adaptation of unattended acoustic area, monitoring sensors to changing ground conditions. 相似文献
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Rodriguez-Cassola M. Baumgartner S. V. Krieger G. Moreira A. 《Geoscience and Remote Sensing, IEEE Transactions on》2010,48(2):781-794
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Brautigam B. Gonzalez J. H. Schwerdt M. Bachmann M. 《Geoscience and Remote Sensing, IEEE Transactions on》2010,48(2):702-715
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The TerraSAR-X Satellite 总被引:3,自引:0,他引:3
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针对合成孔径雷达(SAR)舰船斜框检测数据集较少,难以满足算法发展和实际应用需求的问题,该文公开了SAR舰船斜框检测数据集(RSDD-SAR),该数据集由84景高分3号数据和41景TerraSAR-X数据切片及2景未剪裁大图,共127景数据构成,包含多种成像模式、多种极化方式、多种分辨率切片7000张,舰船实例10263个,通过自动标注和人工修正相结合的方式高效标注。同时,该文对几种常用的光学遥感图像斜框检测算法和SAR舰船斜框检测算法进行了实验,其中单阶段算法S2ANet检测效果最佳,平均精度达到90.06%。通过实验对比分析形成基准指标,可供相关学者参考。最后,该文通过泛化能力测试,分析讨论了RSDD-SAR数据集训练模型在其他数据集和未剪裁大图上的性能,结果表明:该数据集训练模型具有较好的泛化能力,说明该数据集具有较强的应用价值。RSDD-SAR数据集可在以下网址下载:https://radars.ac.cn/web/data/get Data?data Type=SDD-SAR。 相似文献