A unified receiver for MIMO communication with imperfect channel knowledge

The problem of MIMO communications with imperfect channel knowledge at the receiver is considered. Imperfect channel knowledge results from errors due to noise and errors due to time variations which cause the channel estimates to become outdated. A receiver structure named the Unified Generalized Likelihood Ratio Detector (UGLRD) is presented. The UGLRD is based on joint symbol-channel estimation, and it accommodates variations in the availability and the reliability of the Channel State Information (CSI) at the receiver. It can be applied to blind and to differential MIMO systems. The performance of this receiver is compared with that of a conventional MIMO receiver for different channel conditions. It is shown that the UGLRD outperforms the conventional receiver at the cost of higher computational complexity which is addressed using an efficient search algorithm.