Experiment validation of inclined geosynchronous SAR foucusing using Beidou IGSO satellite

One of the GEO SAR´s characteristics of long integration time guarantees its fine resolution. But on the contrary, the ultra-long time boosts the multiple influences and then affects the focusing severely. In this paper, a validation experiment is presented to verify the feasibility of GEO SAR imaging under the condition of long integration time of around several hundred or even thousands of seconds. The experiment employs the Chinese Beidou IGSO navigation satellites as the illuminator of opportunity. The receiver is deployed on the top of a building and then a space-surface Bistatic SAR (SS-BISAR) configuration is constructed. A transponder consisting of two antennas and an amplifier is constructed for evaluating the resolution. The images of the transponder and the natural scene are focused well, which can validate the GEO SAR imaging feasibility though the linear track and constant speed assumptions fail.