Dynamics of Spatial Eigen Modes in Measured MIMO Channels with Different Antenna Modules

This paper presents results from an extensive MIMO field trial campaign aimed at comparing the eigen mode dynamics of three alternative user devices when deployed in realistic operating scenarios. Two novel parameters, the eigen coherence time and eigen coherence bandwidth, are introduced and the differences amongst the candidate antenna systems examined. The greater azimuth coverage of the reference dipole antennas is shown to induce lower coherence times and bandwidths, when compared to the antenna embedded within the laptop and PDA devices. An inverse power relationship between the eigen coherence bandwidth and r.m.s. delay spread and its dual is also investigated.