Reciprocal-Filter-Based STAP for Passive Radar on Moving Platforms

This paper addresses the problem of clutter cancellation and slowly moving target detection in digital video broadcast-terrestrial-based passive radar systems mounted on moving platforms. First, we show that conventional processing approaches based on the availability of multiple receiving channels might be ineffective in the considered scenarios due to the impossibility to control the employed waveform of opportunity. Therefore, an appropriate space-time adaptive processing scheme is proposed to cope with the Doppler spread clutter returns aiming at ground moving target indication applications. It exploits the benefits of the reciprocal filtering strategy applied at a range compression stage together with a flexible displaced phase center antenna approach. The effectiveness of the proposed scheme is demonstrated via application to a simulated dataset and then tested against experimental data collected by multichannel passive radar on a maritime moving platform.

I. Introduction

With the considerable attention it has attracted in the last years, passive radar is continuously stimulating research activities aimed at going one step further. An overview of recent developments and challenges, new areas of research, and applications can be found in [1]–[4]. Recent studies have looked at the possibility to develop advanced imaging and surveillance capabilities by exploiting passive radar receivers (Rx) mounted on a moving platform [5]–[14]. These studies are fostered also by the progress in miniaturized and powerful hardware that makes it feasible to install multichannel passive radar systems—often addressed as passive coherent location (PCL) systems—on moving platforms such as small boats or light aircraft.