星载寄生式SAR多普勒特性分析

本文基于星载双基地雷达空间几何关系,给出了星载寄生式SAR系统中小卫星多普勒参数的两种表达形式,进一步给出了与多普勒特性相关的几个重要系统参数的表达式。分析了基线和相对速度对小卫星多普勒特性参数偏移主星参数的影响,指出基线是主要影响因素;对多普勒中心频率影响大,对多普勒调频斜率及方位分辨率影响小。分析了利用寄生式SAR提高方位分辨率的能力和限制因素。

Doppler Property Analysis of Spaceborne Parasitic SAR

Based on geometric relationship among satellites, the Earth and radar, expressions of two Doppler parameters of SAR radar onboard small satellites of spaceborne parasitic SAR system are given in two different forms. From the results, expressions of several other important system parameters related to Doppler property are also given. Influences of baseline and relative velocity on these parameters are analyzed. Its found that baseline extent is the main influence. Doppler centric frequency is influenced much greater than Doppler FM rate and azimuth resolution is. Capability and limitation of improving azimuth resolution by combining the data obtained by different small satellites are analyzed too.