EM Algorithm for Sequence Estimation over Gauss-Markov ISI Channels
نویسندگان
چکیده
| This paper presents a new algorithm, based on an EM (Expectation-Maximization) formulation, for ML (maximum likelihood) sequence estimation over unknown ISI (inter-symbol interference) channels with random channel coeecients which have a Gauss-Markov fast time-varying distribution. By using the EM formulation to marginalize over the channel coeecient distribution, maximum-likelihood estimates of the transmitted sequence are obtained. This EM algorithm is shown to perform better , in terms of BER, than existing algorithms which perform jointly-optimal sequence and channel estimation, or which do not take into account fast time-varying channel eeects.
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