Robust joint channel estimation and symbol detection over MIMO channels using EM algorithm
An expectation maximization (EM) algorithm for joint channel tracking and symbol detection at the receiver in a multi-input multi-output (MIMO) frequency-selective fading environment is proposed in this research. Based on the recursive EM procedure in conjunction with the BCJR algorithm, we develop an iterative algorithm that performs the minimum mean squared error (MMSE) channel estimation and the maximum a posterior (MAP) probability symbol detection jointly. The per- formance of the proposed algorithm is evaluated via simulation and compared with that of Kalmanfiltering with hard decision feedback. It is also demonstrated that the new algorithm has robust performance in the presence of a severe channel model mismatch. I. INTRODUCTION