A new technique is proposed for robust multiuser detection in the presence
of non-Gaussian ambient noise. This method is based on minimizing a certain
cost function (e.g., the Huber penalty function) over a discrete set of ca
ndidate user bit vectors. The set of candidate points are chosen based on t
he so-called "slowest-descent search," starting from the estimate closest t
o the unconstrained minimizer of the cost funct:ion and along mutually orth
ogonal directions where this cost function grows the slowest. Simulation re
sults show that this new technique offers substantial performance improveme
nt over the recently proposed robust multiuser detectors with little attend
ant increase in computational complexity.