MIMO Channel Model with Propagation Mechanism and the Properties of Correlation and Eigenvalue in Mobile Environments

Abstract EN

This paper described a spatial correlation and eigenvalue in a multiple-input multiple-output (MIMO) channel.

A MIMO channel model with a multipath propagation mechanism was proposed and showed the channel matrix.

The spatial correlation coefficient formula ρi−j,i′−j′(bm) between MIMO channel matrix elements was derived for the model and was expressed as a directive wave term added to the product of mobile site correlation ρi−i′(m) and base site correlation ρj−j′(b) without LOS path, which are calculated independently of each other.

By using ρi−j,i′−j′(bm), it is possible to create the channel matrix element with a fixed correlation value estimated by ρi−j,i′−j′(bm) for a given multipath condition and a given antenna configuration.

Furthermore, the correlation and the channel matrix eigenvalue were simulated, and the simulated and theoretical correlation values agreed well.

The simulated eigenvalue showed that the average of the first eigenvalue λ1 hardly depends on the correlation ρi−j,i′−j′(bm), but the others do depend on ρi−j,i′−j′(bm) and approach λ1 as ρi−j,i′−j′(bm) decreases.

Moreover, as the path moves into LOS, the λ1 state with mobile movement becomes more stable than the λ1 of NLOS path.