KOMPSAT-5 spotlight SAR processor using FSA with calculation of effective velocity

In KOMPSAT-5 program, Korea Aerospace Research Institute has made SAR imaging chain analysis tool to evaluate imaging system of KOMPSAT-5. The tool consists of a simulator and a processor. The simulator simulates observation of a scene by the operational mode of KOMPSAT-5 and generates SAR raw data. The processor generates an image of the scene. This paper is about the second part of processing the simulated raw data that is acquired by the step steering sliding spotlight mode of KOMPSAT-5. For this observation mode, dechirp on receive is operated in receiving the echoes. So, extended frequency scaling algorithm is used to process the raw data in order to directly handle the dechirped data. This paper mainly contributes for the accuracy of effective velocity. The effective velocity criterions for range and azimuth processing allows that the processor uses only one scene center effective velocity in range processing and several ones in azimuth processing. In this paper, a method to increase the accuracy of calculation of effective velocity is also proposed. Simulation result shows that the proposed method is valid.