Imaging Performance Analysis of Space-Air Non-Cooperative BSAR

Space resolution expressions presented in terms of satellite parameters for space-air non-cooperative BSAR system are derived considering the effect of Earth rotation and circular Earth surface on spacecraft platform. Based on the expressions, spatial attitude optimization scheme for aircraft platform is given to optimize space resolution once the spacecraft as non-cooperative transmitter is determined. The derived expressions also provide insight into the relationships between the resolution performance and satellite orbit parameters: the orbit altitude is of the importance rather than the orbit inclination angle; antenna beamforming technique is necessary for system utilizing low orbit spacecraft in strip mode since the imaging scene length is very limited and the resolution performance is not satisfying. Simulation results with Envisat satellite and GLONASS satellite as transmitter respectively demonstrate these analyses