一种外辐射源雷达的稀疏层析成像方法

外辐射源雷达可利用第三方照射源完成静默条件下对目标的探测，具有优秀的四抗能力，在强电磁对抗环境下具有先敌发现的战场感知优势，一直是各军事强国的重要发展方向之一。外辐射源雷达成像技术可提供更为丰富的目标感知信息，具有较好的军事和民用发展前景。针对外辐射源雷达成像面临的第三方辐射源带宽窄、分辨率低等问题，利用层析成像原理构建系统模型，通过扩展目标回波的波束域空间谱提升系统分辨率，并通过稀疏恢复技术在部分角度观测信息条件下实现对目标的高分辨成像。针对目标在观测时间内非理想运动导致的相位误差，基于定点迭代方法改善成像对比度，提升了系统成像性能。理论分析及仿真实验验证了所提方法的有效性。

Sparsity-Driven Passive Radar Tomography Imaging Based on Fixed Point Iterative Method

The passive radar imaging system exploits the opportunity illuminator as its transmitter. The system realized thedetection of targets we are interested in by deploying multiple receivers around the target area. Comparing with the traditional radarimaging system, the passive radar imaging system has advantages of low cost, robustness against to deliberate directional inferenceand strong survivability. Taking account of the various advantages above, wide attention has been attracted from many researchorganizations. The signal transmitted by the opportunity illuminator is narrow bandwidth which makes the range resolution cell poor.Aiming at solving the problem listed above, the model of the passive radar imaging system is built based on the principle oftomography. Taking account of the sparse distribution of the scatters of the target, a high resolution imaging algorithm is developedbased on the compressed sensing. Finally, the influence of the imperfect motion of the moving platform on the received signal isanalyzed. The contaminated signal model is reformed. The corresponding compensation method based on the fixed-point iterativemethod is proposed for improving the performance of the imaging system by correcting phase errors. The theoretical analysis andnumerical simulations verify the effectiveness of the method.