Channel equalization and the Bayes point machine

Edward Harrington, Jyrki Kivinen, Robert C. Williamson

Abstract: Equalizers trained with a large margin have an ability to better handle noise in unseen data and drift in the target solution. We present a method of approximating the Bayes optimal strategy which provides a large margin equalizer, the Bayes point equalizer. The method we use to estimate the Bayes point is to average N equalizers that are run on independently chosen subsets of the data. To better estimate the Bayes point we investigated two methods to create diversity amongst the N equalizers. We show experimentally that the Bayes point equalizer for appropriately large step sizes offers improvement on LMS and LMA in the presence of channel noise and training sequence errors. This allows for shorter training sequences albeit with higher computational requirements.