Analysis of Widely Linear Iterate-Averaging Affine LMS Algorithm for DS-CDMA MAI Suppression

Motivated by the recent development on iterate-averaging (IA) for accelerating convergence rates of stochastic approximation algorithms, and widely linear (WL) processing for improving performance of the linear minimum mean-squared error (MMSE) multiuser receivers, in this paper, a widely linear IA affine LMS algorithm (WL IA-ALMS) for adjustment of the WL MMSE filter for multiple access interference (MAI) suppression for direct-sequence code-division multiple access (DS-CDMA) is introduced and analyzed. We give analytical expressions for the stability region in the mean and in the mean square, the steady-state signal-to-interference-plus-noise ratios (SINR) of the proposed algorithms. We also investigate its speed of convergence for DS-CDMA MAI suppression.