A Novel 2-D Spectrum Model for Bistatic SAR Based on Hyperbolic Approximation

Abstract

Due to the fact that the range history of bistatic synthetic aperture radar (SAR) doesn’t follow the hyperbolic function, the accurate analytical spectrum of bistatic SAR cannot be obtained directly by the principle of stationary phase (POSP). In this paper, we approximate the range history of bistatic SAR by the hyperbolic function, and propose a novel two-dimensional (2-D) analytical spectrum model for bistatic SAR. The huge advantage of this novel 2-D analytical spectrum is that the equivalent radial velocity of any scatter point in the observed scene, with respect to the radar platform, is not only the same but also invariant with the equivalent range. Further, based on this novel spectrum model, the wavenumber domain algorithm (WDA) could be applied to image the whole observed scene. Finally, the simulation and realistic data imaging results also validate that this novel spectrum model is correct and effective.