Multiplexing efficiency of MIMO antennas in arbitrary propagation scenarios

Multiplexing efficiency has recently been proposed as a performance metric for characterizing the absolute efficiency of MIMO antennas in a reference channel. In this work, we generalize this metric to account for arbitrary propagation channels, so the impact of the channel can also be studied. Using the extended definition of multiplexing efficiency, the respective roles of effective antenna gain and signal correlation due to non-isotropic incident fields can be clearly identified. A numerical evaluation based on two MIMO terminal prototypes and four different propagation scenarios is performed to demonstrate the effectiveness of the generalized metric. We find that the MIMO antenna with high total antenna efficiency and good pattern diversity offers a robust multiplexing efficiency performance in all the considered propagation scenarios.