The CFAR Detection of Ground Moving Targets Based on a Joint Metric of SAR Interferogram's Magnitude and Phase

Abstract

By analyzing the backscattering difference between moving targets and stationary clutter contained in the interferogram, a constant false alarm rate (CFAR) detecting method based on a joint metric of synthetic aperture radar (SAR) interferogram's magnitude and phase (IMP) for ground moving targets has been proposed in this paper. First, utilizing the exclusive mapping relationship between interferometric phase and the module of corresponding vector, and combining interferometric magnitude, a new joint metric, called IMP metric, has been constructed. Second, under the frame of multiplicative model, based on the complex Wishart-distribution, the IMP metric's statistical model, simply denoted as <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">S</i> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sup> distribution, has been derived. Meanwhile, the parametric estimators of the <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">S</i> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sup> distribution have also been presented based on the Mellin transform. Finally, the CFAR threshold of ground moving target detection using the <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">S</i> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sup> distribution has been given analytically. The experiments performed on measured dual-SAR images not only show the effectiveness of the IMP metric's statistical models and the parametric estimators, but also prove the good performance of the proposed CFAR detecting method.