Eigenvalue analysis and its modeling for 2×2 MIMO channel capacity based on indoor measurements

This paper aims at the eigenvalue analysis and its modeling for 2×2 (i.e., 2 transmit and 2 receive antennas) Multiple Input Multiple Output (MIMO) channel capacity based on Non Line-Of-Sight (NLOS) wideband indoor measurements. Our channel sounding system is the portable Band Exploration and Channel Sounding (pBECS) System, which works at a carrier frequency of 2.58GHz with 20MHz 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 the eigenvalue characteristics, we derive mean and variance of eigenvalues which are a function of the absolute values of TxACC and RxACC, |TxACC| and |RxACC|, and then model the eigenvalues for 2×2 MIMO channel capacity. Monte Carlo simulations are used to generate the eigenvalue realizations according to the model. The results are compared with the measured data and good agreements are found.