Experimental Evaluation of MIMO Antena Selection System using RF-MEMS Switches on a Mobile Terminal

This paper describes experimental results of an antenna selection system that is applied to a receiver side of multiple- input multiple-output (MIMO) systems. We proposed an antenna selection system that each MIMO receive branch has different polarization and directional pattern antennas and selects one antenna combination by using radio frequency micro electro mechanical system (RF-MEMS) switches. A 2 x 2 MIMO -OFDM transmission system is constructed to evaluate the performance of the proposed antenna selection system, which can not only measure real-time bit error rate (BER) but also control the antenna switch based on an antenna selection algorithm. BER measurement experiments were conducted in an indoor office environment, and it was found that more than 3 dB receive power improvement was achieved with the proposed antenna selection system comparing to the vertical polarization fixed receive antennas from the result of the averaged BER performances.