Ground moving target indication of polarimetric interferometric synthetic aperture radar using joint scattering vector

Abstract

Ground moving target indication (GMTI) plays a critical role in both civilian applications and military applications. The accuracy of complex images coregistration is a major factor for multichannel synthetic aperture radar (SAR) GMTI. Moreover, polarimetric interferometric SAR (PolInSAR) represents a growing strength in multi-function radar systems. In response to this, we propose a new SAR-GMTI approach tailored for the PolInSAR system. To address the deterioration in clutter suppression performance caused by the coregistration errors, we construct a joint scattering vector (JSV) for polarimetric SAR (PolSAR) by incorporating the neighbouring vectors of the central pixel. Subsequently, the covariance matrix of JSV is estimated and subjected to eigen-decomposed. Clutter suppression of the PolInSAR system for GMTI is performed using eigen-subspace projection, where the JSV is projected onto noise subspace. This method is robust against coregistration errors since all ground moving target information is encapsulated within the JSV. Furthermore, the improvement factors with different clutter backgrounds (by changing the signal-to-clutter-plus-noise-ratio, SCNR) are analysed. The effectiveness of the proposed JSV-based method is validated using simulated PolInSAR data.