A NLCS focusing approach for low frequency UWB one-stationary bistatic SAR

In this paper, we outline a modified nonlinear chirp scaling algorithm (NLCSA) for one-stationary bistatic Synthetic aperture radar (BiSAR) using low frequency (LF) and ultra wideband (UWB) signal. The existing NLCSAs for one-stationary BiSAR would be invalidated in a LF and UWB application, because the higher order phase error (HOPE) due to the Taylor series approximation can´t be ignored in this case. In this paper, we first analyze the effect of the HOPE on bistatic LF UWB SAR imaging theoretically. Then, a modified method based on higher order phase compensation (HOPC) and block processing is proposed to deal with the HOPE. Finally, the simulation results demonstrate the correctness of the theory analyses and the validity of the proposed algorithm presented in this paper.