Abstract:The development of Doppler parameter estimating algorithm of bistatic SAR is a pivotal issue, which is still in progress and not sufficiently solved. This paper describes firstly the special case of equal velocity vectors and parallel flight paths of transmitter and receiver, and then makes detailed and mathematical study on the character of Doppler parameter under the above bistatic SAR configuration. Based on the above analysis, this paper provides a new Doppler parameter estimating algorithm of bistatic SAR by Radon transform, which can gets accurate Doppler center and Doppler rate. As a result, it is a feasible Doppler parameter estimating algorithm of bistatic SAR, of which the validity is also proved by the simulation of computer in the last.