Efficient Simulation of Space-Time Correlated MIMO Mobile Fading Channels

Simulation of multiple-input multiple-output (MIMO) fading channels, with crosscorrelated subchannels, is of paramount importance in performance evaluation of space-time techniques in multiantenna systems. This paper focuses on four methods to simulate several spatio-temporally crosscorrelated stationary complex Gaussian processes: the spectral representation method, the sampling theorem method, the random polynomial method, and the circulant embedding method. The first three methods are based on parametric random representations, which consist of the superposition of deterministic functions with random coefficients and parameters, whereas the fourth one is built upon circulant embedding of the covariance matrix and the use of fast Fourier transform (FFT), to diagonalize a block circulant matrix . In this paper we provide a comprehensive theoretical analysis of the computational complexity of all the four methods. The performance of these techniques are also assessed, via extensive simulations, in terms of the quality of the generated samples. Our theoretical analysis and simulation results show that for MIMO channel simulations, the spectral method has much less computational complexity, with the same simulation accuracy as other methods. Matlab files for all the four methods are available at http://web.njit.edu/~abdi.