Distributed Satellite Sar System At-of Insar Mode Velocity Precision Study

The Cluster Micro-Satellite Synthetic Aperture Radar (SAR) System is an innovative SAR system brought forward recently . The along-track interferometric SAR (InSAR) imaging is one of the principal operation modes of the system. The combine of the cluster satellites can obtain the phase of the along-track interferometric SAR (AT-InSAR) to measure the slow moving targets. The main content of this paper can be concluded as followings:1) This paper investigates the influence of the main parameters measure error to the AT-InSAR speed measurement accuracy, and analyzes the influence of the interferometric phase error and the incidence angle error caused by thermal noise to the imaging precision.2) This paper research mainly the influence of the cluster satellite circumnavigation,Earth-Rotation,satellite attitude to the baseline variation and the speed measurement accuracy, and give the correcting mathematical formula and the relative curvature. By computer simulation , the results shows that when the baseline length is longer , the accuracy of speed measurement is better, and in the same time, the range of speed measurement is also narrower. Besides , the baseline size should be corrected real-time to improve the precision of speed measurement.On the whole, this paper research the influence of the interferometric phase,the incidence angle,the baseline and the satellite attitude to the speed measurement accuracy in details, and we get some useful results. It is believed that the results of the research can provide theory and design for the Cluster Micro-Satellite system.