Investigation of diversity techniques considering receiver structure in MIMO systems

This paper examines receiving antenna selection (RAS) and receiving antenna combination (RAC) techniques from the viewpoint of receiver structure with the aim of improving bit error rate (BER) performance for receivers in MIMO (multi-input multi-output) systems. We assume two receiver structures. One is a structure for controlling gain in received signals centrally for all receiving antennas (CC receiver). The other is a structure for controlling gain in received signals individually in each receiving antenna (CI receiver). We show that a CC receiver can obtain good BER performance when utilizing RAS/RAC techniques using the channel matrix eigenvalue (RAS/RAC-E). Additionally, we consider RAS/RAC techniques using the phase of the channel component (RAS/RAC-PC) and received power (RAS/RAC-RP) in a CI receiver. We then simulate BER performance when employing the proposed RAS-PC and RAS-RP techniques under Rayleigh fading channels. The results clearly show that the RAS/RAC-PC techniques are able to obtain good BER performance for a CI receiver.