Space-Time Array Processing for Radar and Communications

摘要

We developed a new approach using EM derived algorithms for MLSE over channels having unknown FIR impulse coefficients with known statistics. The ML formulation for optima sequence estimation over random channels is generally intractable to solve directly. However, the EM algorithm is a technique which can effectively be used to solve such intractable ML problems. Specifically, by using EM to marginalize over the channel coefficient distribution, optimal estimates of the transmitted sequence are derived which can achieve lower bit- error-rates than methods which jointly estimate both the transmitted sequence and the channel coefficients, and methods based on first optimally estimating the channel coefficients.