SECOND-ORDER VERSUS FOURTH-ORDER MUSIC ALGORITHMS : AN ASYMPTOTICAL STATISTICAL ANALYSIS
Éric Moulines · 1991
Direction finding techniques are usually based on the 2ndorder statistics of the received data. In this paper, we propose a MUSIC-like direction finding algorithm which uses a matrix-valued statistic based on the contraction of the 4thorder cumulant tensor of the array data (4-2 MUSIC). We then derive, in a unified framework, the asymptotic covariance of estimation errors for both 2nd-order and 4th-order based MUSICs, and show that the 4th-order method can perform equally well or even better than the 2nd-order method, even when the noise spatial structure is known. 1. INTRODUCTION Current array processing techniques are based on the second-order statistics of the received signals. In many situations, in particular in digital communications, received signals are non-Gaussian so that they contain valuable statistical information in their moments of order greater than two. In these circumstances, it makes sense to develop array processing techniques that exploit higher-order information...