  This paper aims at tackling the problem of signal detection in flat-fading
channels. In this context, receivers based on the expectation propagation
framework appear to be very promising although presenting some critical issues.
We develop a new algorithm based on this framework where, unlike previous
works, convergence is achieved after a single forward-backward pass, without
additional inner detector iterations. The proposed message scheduling, together
with novel adjustments of the approximating distributions' parameters, allows
to obtain significant performance advantages with respect to the
state-of-the-art solution. Simulation results show the applicability of this
algorithm when sparser pilot configurations have to be adopted and a
considerable gain compared to the current available strategies.
