An OFDM Rayleigh Fading Channel Simulator

Several models have been proposed for the simulation of Rayleigh fading channels. However, existing simulators lack to properly consider the correlation between the subchannels of an OFDM system. We use a recently developed cross-correlation function that describes both temporal and frequency correlation in order to generate channel parameters. This correlation function is decomposable into multiplication of two correlation functions. The first term characterizes only the temporal correlation and the other characterizes the correlation between subchannels. Using this property, the proposed simulator is implemented in cascade of two steps. In the first step, we propose an improved IFFT method for generation of multiple independent temporally correlated complex Gaussian processes following the given temporal correlation. We then transform these processes into a vector random processes by a transformation which is obtained by factorization of the frequency-correlation matrix. Our results reveal that the proposed technique accurately generates the desired statistical properties. This method is efficient in terms of computation complexity and runtime cost.