Optimum step size determination for FDPM-based CIR estimator for OFDM systems

Abstract

Fast Data Projection Method (FDPM) subspace tracking algorithm has been demonstrated to exhibit high convergence rate towards orthonormality. This was shown to be the fastest among all competing algorithms of the same order of computational complexity. However, its convergence rate depends largely on the selection of its step size. Coincidentally, this is the only parameter needed to be specified for the algorithm, making its structure simple in comparison with other algorithms. In the original article, only the region in which the step size could be selected in order to ensure stability is given. However, in this article an optimum step size is determined through computer simulation for the FDPM algorithm in the context of channel impulse response (CIR) estimator for Orthogonal Frequency Division Multiplexing (OFDM) Systems.