Matching Strategies for Multiantenna Arrays

We analyze the achievable rates of multiantenna systems taking the coupling in compact arrays into account. We compare the performance of the downlink and of the uplink in single user MISO, SIMO and MIMO scenarios with and without decoupling and matching multiports (DMNs). DMNs provide us with decoupled ports at both ends of the links, which enable the direct usage of capacity results available in the literature. But for large numbers of antennas on the base station (BS) the implementation of the DMNs become involved and limit the bandwidth. Therefore it is worthwhile to investigate a system model where each antenna is connected to an amplifier directly or through a simple matching two-port. For wideband systems, this is an interesting alternative, because the losses in the DMNs and their frequency limited capability for decoupling and matching let the system without them provide larger achievable rates.