An analysis method of double fading MIMO channels including LOS environments

This paper gives an analysis method of i.i.d. (independent and identically distributed) double fading channels including LOS (line of sight) environment which are typically found in keyhole MIMO (multiple input multiple output) models. To investigate the potential of LOS double fading (double Rician fading) MIMO channels, the density function of SNR (Signal to Noise Ratio) which corresponds to the only one non-zero eigenvalue of channel correlation matrix is considered. After the description of the exact expression with an infinite series form, an approximation formula of SNR density with a simple monomial form is given utilizing Nakagami m approximation of Rician distribution. Through computer simulations, the effectiveness of the proposed formulae is verified, and the advantage of the approximated formula particular in case of large array size and/or large Rician factor is demonstrated.