  Theoretical analysis of orthogonal frequency division multiplexing (OFDM)
systems equipped at the receiver by a non-linear impulsive noise suppressor is
a challenging topic in communication systems. Indeed, although an exact
closed-form expression for the output signal-to-noise ratio (SNR) of such OFDM
systems is available for widely used impulsive noise models, theoretical
analysis of the associated symbol error rate (SER) is still open. So far, the
analytical SER expressions available in the literature approximate the
time-domain impulsive noise, as Gaussian distributed in the discrete frequency
domain. Conversely, this work presents an accurate analysis of the distortion
noise at the nonlinearity output exploiting a Gaussian mixture model (GMM). By
using GMMs we unified the approach of SER prediction for unmitigated systems,
as well as for the mitigated ones, equipped by non-linear impulsive noise
suppressors, including blanking, clipping, clipping-blanking and attenuating
processors. Closed form expressions for the SER are derived both for non-fading
and frequency-selective Rayleigh and Rician fading channels affected by
impulsive noise which is represented by GMMs, thus including Bernoulli-Gaussian
(BG), Middleton Class-A, as well as (approximated) alpha-stable noise.
Theoretic SER performance are compared with simulations, showing very good
agreement for all the impulsive noise scenarios and the non-linear suppressors.
