A nonlinear diversity combiner of binary signals in the presence of impulsive interference

A Middleton Class-A (MCA) model is one of the most accurate statistical-physical models for narrowband impulse noise. The previous studies show that time diversity can efficiently be used to reduce the impact of MCA noise. The optimum combiner in such noise consists of a nonlinear preprocessor followed by a conventional combiner. Since an MCA noise process consists of an infinite number of noise states, there is no closed-form solution of the optimum nonlinearity. In this paper, we adopt a two-term model for the MCA process, which is further approximated to a simpler noise model. Therefore, we introduce a closed-form approximation of the optimum nonlinearity in the presence of real-valued MCA noise. In fading channels, we use a complex extension of an MCA model. We show how the nonlinearity operation maintains the diversity advantage in such a noise model.