由于海面的随机运动特性使得海面回波相干时间与陆地目标有很大的差异,回波的相干时间对SAR系统参数和指标设计有很大的影响。该文研究了双站SAR的海面回波相干时间,通过分析波浪随机运动造成的回波相位延迟,给出了波浪随机运动对双站SAR成像的影响。得出了双站SAR海面回波相干时间与波浪谱的关系,给出了双站SAR方位向分辨率与相关时间的关系,并通过仿真分析了相干时间与若干重要参数的关系。
The coherent time of echo signal of ocean surface is much different from that of land because of its stochastic movement, which is related to the system parameters designation. The ocean echo signal coherent time of bistatic SAR is studied in this paper. The echo signal phase due to the wave movement is analyzed, and the effect on the bistatic SAR imaging of the ocean wave stochastic movement is given. The formula of coherent time is given, the relationship between the azimuth resolution and the coherent time is given, and the relationships between the coherent time and some factors are simulated and analyzed.