In this paper we perform some trial measurements and study the effects of various communication environments on the system MIMO rank; it utilizes the ZigBee-built system to measure the receiver signal strength and trough the resulting RSSI levels to estimate the effective system MIMO rank. The various communication environments studied are formed by intergrating the following system parameters such as the physical mumber of MIMO antennas, the number of floors the transmission path flows, whether the transmission path is clear or blocked and are there an isolations set up between transmitting antennas and how the isolations are arranged etc.
