  Channel uncertainty and co-channel interference are two major challenges in
the design of wireless systems such as future generation cellular networks.
This paper studies receiver design for a wireless channel model with both
time-varying Rayleigh fading and strong co-channel interference of similar form
as the desired signal. It is assumed that the channel coefficients of the
desired signal can be estimated through the use of pilots, whereas no pilot for
the interference signal is available, as is the case in many practical wireless
systems. Because the interference process is non-Gaussian, treating it as
Gaussian noise generally often leads to unacceptable performance. In order to
exploit the statistics of the interference and correlated fading in time, an
iterative message-passing architecture is proposed for joint channel
estimation, interference mitigation and decoding. Each message takes the form
of a mixture of Gaussian densities where the number of components is limited so
that the overall complexity of the receiver is constant per symbol regardless
of the frame and code lengths. Simulation of both coded and uncoded systems
shows that the receiver performs significantly better than conventional
receivers with linear channel estimation, and is robust with respect to
mismatch in the assumed fading model.
