RANSAC-based Flight Parameter Estimation for Registration-based Range-dependence Compensation in Airborne Bistatic STAP Radar with Conformal Antenna Arrays

Abstract

We consider space-time adaptive processing (STAP) in a bistatic radar configuration and when the radar returns are recorded by a conformal antenna array (CAA). The statistics of the secondary data snapshots used to estimate the optimum weight vector are not identically distributed with respect to range, thus preventing the STAP processor from achieving its optimum performance. The compensation of the range-dependence of the secondary data requires the knowledge of the clutter power spectrum locus. This paper proposes a new RANSAC-based method for estimating, in the case of CAAs operating in arbitrary bistatic configurations, the clutter power spectrum locus or, equivalently, the flight configuration parameters. Based on the knowledge of this locus, we can perform a range-dependence compensation of the snapshots to obtain an accurate estimate of the clutter covariance matrix. End-to-end performance analysis in terms of signal to inference-plus-noise ratio loss shows that the method yields promizing performance.