基于MIMO的ISAR成像算法研究

基于RD算法的ISAR成像在实际应用中由于很多复杂的因素导致可利用的成像积累时间短,有可能达不到所要求的方位向分辨率。在此研究了几种不同情况下,结合MIMO技术对同一目标ISAR成像的算法。它采用多个收发雷达对同一目标发射一组射频信号,通过对接收到的回波信号进行匹配滤波实现距离像压缩,将不同雷达接收到的距离像进行选取、插值、组合,最后对组合后数据进行方位向多普勒分辨成像。理论推导以及仿真实验结果证明,该方法在不同情况下都可以在达到方位向分辨率的前提下,缩短成像所需时间,或者在确保成像时间的前提下,提高成像的分辨率。这样缩短成像时间的方法扩大了ISAR成像的应用范围,提高了ISAR成像效果。

ISAR imaging algorithm based on MIMO technique

inverse synthetic aperture radar（ISAR）imaging based on RD algorithm may not meet the required azimuth reso-lution due to many complicated factors which cause a short available coherent integration time. Combining multiple-input multiple-output （MIMO） technique,the algorithms for ISAR imaging of the same targets in different cases are studied in this paper. Many MIMO radars are adopted to transmit a group of RF signals to the same targets to realize the range profile compression by carrying out matching filtering of the received echo signals,and then the range profiles received by different radars are selected, interpolated and assembled;after that,the azimuth Doppler resolving imaging of the assembled data is performed. The results of theoretical derivation and the simulation experiment show that the coherent integration time of this method is shorter than that of RD algorithm under the condition of the same required azimuth resolution,or its azimuth resolution is higher than that of RD al-gorithm under the condition of the same required coherent integration time. That means the applicability and the quality of ISAR imaging are improved by this method.