Linear equalization via factor graphs

We apply the factor graph framework to the techniques of linear equalization and decision feedback equalization to obtain a new class of low complexity equalization algorithms. The estimation of Gaussian processes has been studied in previous work, and the application of factor graphs to this problem is a recent extension. Here we use a factor graph model for the specific estimation problem of equalization and use the sum-product algorithm to obtain the desired estimate. We derive reduced complexity message passing update equations and detail the complexity of the resulting algorithms.