Adaptive Multi-Element Receiver Structure for Maximum-Likelihood Sequence Estimation in a Spatially Distributed Interference Channel

An optimum receiver structure is described for maximum-likelihood estimation of a linearly modulated binary data sequence received in the presence of spatially distributed interference by a multi-element antenna array. The optimum structure consists of an interference suppression spatial filter followed by a matched filter sampled at the baud rate, and a recursive nonlinear processor employing the Viterbi algorithm to perform maximum-likelihood sequence estimation. This receiver provides an extension of known results for single-element digital communication systems to the case where a multi-element array capability is available and results in a practically implementable optimum spatial/temporal processor.