基于球面波聚焦卷积算法的近场共焦层析成像

Confocal Tomography Imaging in Near-field Based on Spherical Wave Convolution Algorithm

针对合成孔径雷达三维层析成像实现三维层析成像算法仅适用于远场、靠增加基线数提高分辨率的办法会大大增加系统复杂度等问题,提出一种基于近场圆周扫描的共焦层析成像诊断方案。方案结合合成孔径与共焦层析成像思想,修正球面波聚焦卷积算法的映射关系,完成空时共焦成像。仿真和试验结果表明该方案可以克服高度模糊,通过单条基线一次扫描,进行准三维近场成像。

Tomography imaging of synthetic aperture radar can realize 3D tomography although its algorithm is simple, computation quantity is small, but is mainly suitable for the far field conditions. In addition, by increasing the number of baseline to improve the resolution will greatly increase the system complexity. According to the above problems, a tomography imaging technique in near-field using eonfocal cir- cular SAR was proposed. Two techniques of synthetic aperture and eonfocal imaging were combined to achieve space-time confocal imaging using SAR on a circular or curved orbit. The results of digital simulation and experiment show that the proposed algorithm overcomes alti- tude ambiguity and has the capability to extract 3-D imaging information from a target scene.