1. A detector for estimating channel data probabilities in a multi-channel communication system comprising: a receiver configured to receive a multi-channel signal and output an observed signal; a Gibbs sampler circuit coupled to the receiver and configured to generate stochastically selected channel data hypotheses based in part on the observed signal and a channel model; and a channel data probability estimator coupled to the receiver and coupled to the Gibbs sampler circuit and configured to estimate channel data probabilities by summing conditional data probabilities conditioned on the observed signal and the stochastically selected channel data hypotheses.