Expectation maximization based channel estimation for uplink STBC-MC-CDMA systems

In this work, maximum likelihood (ML) channel estimation for uplink space time block coded multi carrier code-division multiple-access (STBC-MC-COMA) systems is considered in the presence of frequency fading channeL The expectation-maximization (EM) is introduced to avoid matrix inversion for the ML channel estimation problem, We compare this algorithm in terms of the number of used iteration and show that the proposed algorithm converge the same performance of the ML estimator as the increasing number of iterations.