Analysis of MIMO capacity gains for indoor propagation channels with LOS component

We analyse typical indoor propagation scenarios with respect to the capacity gain made available through the use of multiple transmit and receive antennas. In particular, we investigate propagation channels with a strong line of sight component, as evident when the transmit array is in the same room as the receive array. It is found that the capacity gain for the pure LOS component depends highly on the array geometry and the receiver location, such that the capacity gain vanishes rapidly with receiver distance. We show that the existence of stochastic scattering components is beneficial to obtain the maximum capacity gain, thus reducing the dependence on the array geometry and the receiver location. This benefit exists even for a strong LOS component. Quantitative results are provided for wireless LAN systems operating at carrier frequencies around 5 GHz.