ASYMPTOTIC PERFORMANCE ANALYSIS OF BLIND SIGNAL COPY USING 4TH-ORDER CUMULANTS

Blind array processing techniques have been gaining much interest in t he last several years. Conventional array processing algorithms such a s MUSIC assume that the structural information of the array manifold i s known, In blind array processing the structure of the array manifold is assumed to be unknown and needs to be estimated from the available data. In this paper we investigate the performance of blind signal co py algorithms which use fourth-order cumulants to estimate the signals . We derive an asymptotic expression for the upper bound on the qualit y of the estimated signal in terms of the output signal-to-interferenc e ratio. We also introduce two blind algorithms for signal separation using only fourth-order cumulants: one is asymptotically optimal and t he other is suboptimal but significantly simpler, Some insight into th e achievable performance of such algorithms is obtained by numerical e valuation of the bound for several test cases of interest and the resu lts are compared with those obtained by simulations using the aforemen tioned blind algorithms.