A Moving-targets Detection Algorithm for Spaceborne SAR System Based on Two-dimensional Velocity Search Method
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摘要: 采用传统SAR成像方法对星载SAR地面运动目标进行成像处理时,运动目标通常会处于散焦状态,导致运动目标检测性能下降。该文结合RD算法,提出一种基于2维速度搜索的星载SAR运动目标检测算法,通过对运动目标距离向速度和方位向速度进行遍历来匹配运动目标多普勒参数,提取不同搜索速度下运动目标的最强幅度值用于恒虚警检测,可以提高运动目标的检测概率。仿真结果验证了该方法的可行性和有效性。Abstract: The moving target component is often defocused in spaceborne SAR images. Therefore, the moving target detection performance is affected depending on the degree of defocusing. Combined with the RD algorithm, a moving-targets detection algorithm for spaceborne SAR based on a two-dimensional velocity search is proposed. Through velocity search on the distance direction and the azimuth direction, the Doppler parameters of possible moving targets can be matched. Then the strongest value among all the searching velocity results for each pixel is used for Constant False Alarm Rate(CFAR) detector. This core process can improve the detection performance of moving target component. Simulation results validate the effectiveness of the proposed method.
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Key words:
- Synthetic Aperture Radar(SAR) /
- Moving target detection /
- RD algorithm /
- Velocity search
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表 1 不同参数下,运动目标成像性能分析
不同参数 完全匹配(9,4) 失配(7,4) 失配(0,8) 失配(–14,10) SNR (dB) 30.00 29.92 27.35 21.17 SCR (dB) 3.75 3.41 0.67 –2.26 -
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