Modeling of Eigenvalues for MIMO Channel Capacity Based on Outdoor Measurements

This paper aims at modeling of eigenvalues for 2timesN (i.e., 2 transmit and N receive antennas) channel capacity based on non line-of-sight (NLOS) wideband outdoor measurements. Our channel sounding system is the Band Exploration and Channel Sounding System (BECS) 2005, which works at a carrier frequency of 3.7 GHz with 100 MHz bandwidth. From the measured data, we investigate transmit antenna correlation coefficient (TxACC), receive antenna correlation coefficient (RxACC), channel capacity and eigenvalues of HH* where H and (*) are channel frequency response matrix and conjugate transpose. Based on eigenvalue characteristics, we derive mean and variance of eigenvalue which are a function of the absolute value of TxACC, |TxACC|, the absolute value of RxACC, |RxACC|, and the number of Rx antennas, and then model eigenvalues for 2timesN channel capacity. Monte Carlo simulations are used to generate eigenvalue realizations according to the model. The results are compared with the measure data and good agreements are found.