Extended MLSE diversity receiver for the time- and frequency-selective channel

This paper develops an MLSE diversity receiver for the timeand frequency-selective channel corrupted by additive Gaussian noise, when linear constellations are employed. The paper extends Ungerboeck’s derivation of the Extended MLSE receiver for the purely frequency-selective channel to the more general channel with diversity. The new receiver structure and metric assume a known channel. The major contributions of this paper are as follows: (i) the derivation of a finite-complexity diversity receiver that is Maximum Likelihood (ML) for all linear channel models and sources of diversity; (ii) a benchmark, in that the new receiver’s performance is a lower bound on the performance of practical systems; (iii) insight into matched filtering and ML diversity receiver processing for the timeand frequency-selective channel; (iv) bounds on the new receiver’s BER for ideal CSI, in a fast Rayleigh fading channel with multiple independently faded paths.