Computationally efficient channel estimation for space-time block coded system

Space-time coding has been proposed in recent years to provide significant capacity gains over traditional communication systems in wireless fading channels. Most works on space-time coding assume availability of perfect channel state information (CSI) in the receiver. In this paper, a decoupled maximum likelihood (DEML) channel estimator is presented for space-time block coded (STBC) system. The DEML estimator decouples the multi-dimensional problem of the exact maximum likelihood (ML) estimator to a set of one-dimensional problems and, hence, is computationally efficient. An iterative ML detector is proposed to improve the performance of DEML estimator. Simulation results are presented to demonstrate the performance of proposed channel estimator and to make comparisons with perfect channel information system.