Alignment of probe antennas for spatial channel emulator

OTA (over-the-air) performance of MIMO (multiple-input multiple-output) mobile terminals employing multi-antennas must be evaluated using the spatial channel emulator which reproduces the multi-path propagation environment around the mobile terminal. Antenna properties of an antenna correlation in addition to the branch power should be adequately evaluated in the spatial channel emulator. In this paper, we investigate based on the calculation the alignment of probe antennas for a spatial channel emulator considering the power angular spectrum of cluster model taking an antenna correlation that has a substantial impact on MIMO performance as the criterion and we clarify that probe antennas should be appropriately aligned, in terms of spacing and numbers, depending on an intended angular spread of arriving waves.