BER analysis for OFDM with ZF-FDE in Nakagami-m fading channels

In this paper we study the statistical distribution of the enhanced noise after zero forcing frequency domain equalization in an OFDM system transmitting over a Nakagami-m fading channel. With this purpose, we obtain the expression of the density function of the ratio between the modulus of a complex Gaussian random variable (i.e., a Rayleigh distributed random variable) and that of a n-dimensional Gaussian random variable (i.e., a Nakagami-m distributed random variable). From this expression, we derive the density and the distribution of the resulting noise term after zero forcing equalization. Lastly, we present an analytical expression for BER in the scenario under study which is validated through simulations.