Convergence analysis of the least squares constant modulus algorithm

This paper examines the convergence behavior of the least squares constant modulus algorithm in an adaptive beamforming application. The improvement in output SIR with each iteration of the algorithm is predicted for several different signal environments. Deterministic results are presented for an environment containing two tones. Probabilistic results are presented for a constant modulus desired signal with a constant modulus interferer and with a gaussian interferer. The asymptotic improvement in output SIR as the output SIR becomes high is also derived.