An improved model of HF-SAR for estimating surface current velocity

With the requirement of surface current extraction by a single station of high frequency surface wave radar, high frequency SAR (HF-SAR) is proposed and proved to be theoretically feasible. However the old model of HF-SAR is not perfect enough and there are several drawbacks such as Bragg scattering not included, high computation burden and implementation difficulty. Thus in this paper we present an improved model of HF-SAR to overcome the previous drawbacks. For the improved model, Bragg frequency is introduced into the echo signal and an iterative approach to estimate parameters of chirp signals is adopted for velocity estimation algorithms. Also an implementation scheme of HF-SAR on the sea is proposed. Simulation results with the improved model show that the precision of surface current velocity estimation is high enough to meet practical requirements.