Channel tracking for multiple input, single output systems using EM algorithm

This paper investigates the problem of blindly acquiring the channel gains for a synchronized multiuser system using the expectation maximization (EM) algorithm. The EM algorithm takes advantage of the finite alphabet property of the transmitted signal. It also provides MMSE estimates of the transmitted data that can be used by the receiver for decoding purposes. The algorithm has been applied to a multicarrier system and results show that the application of EM in the high SNR case provides significant improvement over traditional channel estimation techniques.