1 Department of Electronic Systems, The Technical Faculty of IT and Design, Aalborg University2 The Faculty of Engineering and Science (TECH), Aalborg University3 Navigation and Communications, Department of Electronic Systems, The Technical Faculty of IT and Design, Aalborg University4 Wireless Communication Networks, Department of Electronic Systems, The Technical Faculty of IT and Design, Aalborg University5 Zhengzhou University6 Zhengzhou University
In this letter, a message-passing algorithm that combines belief propagation and expectation propagation is applied to design an iterative receiver for intersymbol interference channels. We detail the derivation of the messages passed along the nodes of a vector-form factor graph representing the underlying probabilistic model. We also present a simple but efficient method to cope with the "negative variance" problem of expectation propagation. Simulation results show that the proposed algorithm outperforms, in terms of bit-error-rate and convergence rate, a LMMSE turbo-equalizer based on Gaussian message passing with the same order of computational complexity.
I E E E Signal Processing Letters, 2015, Vol 22, Issue 10, p. 1733-1737