基于测高精度最优值的星载分布式InSAR编队构形设计方法

编队构形设计是分布式干涉SAR系统总体设计的关键问题,它必须紧密结合系统性能评价和编队运动规律进行。针对星载分布式干涉SAR的双站、斜视、空间基线等特点,以主星带辅星群分布式InSAR为例,建立干涉测高精度与基线矢量的关系;以直角坐标过渡,建立基线矢量与卫星间轨道根数差的关系,从而建立了测高精度与卫星轨道根数差的关系;以雷达工作的中间时刻达到测高精度最优值为设计准则,得到双星和多星编队设计方法;仿真分析表明根据上述设计方法得到的优化编队构形,其测高性能要优于干涉车轮和干涉钟摆编队。

A Formation Design Approach of the Distributed Spaceborne InSAR Based on Height-measure Optimal Accuracy Value

The formation configuration design of the distributed spaceborne interferometric SAR (DSInSAR) is the key issue of the system design. The system performance optimization and formation flying orbit dynamic characteristic are its two basic restrictions. The DSInSAR has the characteristic of bistatic, squint and spatial baseline. As an example, a master transmitter satellite and multi receiver satellite system is analysized. The relation of height-measure accuracy and baseline vector is established. The relation between the differences of the two satellite orbit roots and baseline vector is set up too. So the baseline vector can be expressed by root difference. A formation designing rule that optimal height-measure accuracy can be acquired in the middle time of the system working is presented. Base on this rule, a design method of the two satellite and multi-satellite formation is presented. Simulation shows that the height-measure accuracy value of the optimal formation configuration is prior to that of interferometric cartwheel and pendulum.