Mimo-Capacities for Broadband In-Room Quasi-Deterministic Line-Of-Sight Radio Channels Derived from Measurements

We present broadband capacity snapshots as well as grid measurements derived with a fast 5times5 MIMO channelsounder in a typical, large-scale, non-mobile, in-room office scenario where we focus on line-of-sight (LOS) transmission channels. The accessible MIMO capacity is compared to its theoretic counterpart which would have been obtained if only the LOS signal without any reflections was considered. Our premise is to enable the user of quantifying the LOS signal's impact on the overall channel capacity for the particular scenario and coinciding to demonstrate the LOS's beneficial effect for the capacity. For a huge amount the beneficial effect of the LOS signal has to be ascribed to its receive signal power increase, an advantage which can hardly be balanced by any measures in the non-LOS case. The results generally indicate the overall capacity staying fairly high even for single channel matrix realizations and widely independent from the current geometric antenna assembly. Besides, strong variations over frequency are observed. These variations are shown to be slightly reducible by rising the number of antennas, but more efficient, larger bandwidths seem to be an appropriate measure for stabilizing the overall channel capacity per bandwidth unit