Robust subspace technique for joint angle/Doppler estimation in /spl alpha/-stable clutter using phased fractional lower-order moments

Abstract

We consider the problem of joint angle and Doppler estimation for space-time adaptive processing (STAP) airborne radar in non Gaussian clutter modeled as a complex symmetric alpha stable (SaS) process. We introduce a new robust MUSIC algorithm named PFLOM-MUSIC which is obtained using a new class of covariance matrix estimate based on the phased fractional lower-order moment(PFLOM). Such matrix and the subspaces spanned by its eigenvectors serve as a basis for a high-resolution angle/Doppler estimation method. The performance of the PFLOM-MUSIC is examined by comparing the estimation results with those of the sign covariance matrix estimate SCM-MUSIC (T. Liu and J. M. Mendel, Aug. 2001). Extensive Simulations demonstrate that our proposed algorithm outperforms the previously reported estimators