On the finite sample behavior of the constant modulus cost
Amir Leshem, A.-J. van der Veen · 2002
We study the location of local minima of the finite sample approximation to the constant modulus cost function. This paper concentrates on source separation. The main result is a connection between the number of samples and the probability of obtaining a local minimum of the finite approximation within a given sphere around the local minimum of the CM cost function. The motivations for our study are two problems: equalization of communication signals, and blind separation of a desired signal in multiuser environment. In order to maintain simplicity we focus on the case of blind beamforming which is somewhat simpler to analyze.