Abstract:

Multiple input multiple output (MIMO) relaying techniques can greatly improve the spectral efficiency and extend network coverage for future wireless systems. This article investigates a multiuser MIMO relay channel, where a base station (BS) with multiple antennas communicates with multiple mobile stations (MS) via a relay station (RS) with multiple antennas. The RS applies linear processing to the received signal and then forwards the processed signal. The dual channel conditions between MIMO relay multiple access channel (MAC) and broadcast channel (BC) are first developed for single-relay scenario with white Gaussian noise. Then the MAC-BC duality for MIMO relay systems is established by proving that the capacity region of MIMO relay MAC is equal to that of dual MIMO relay BC under the same total network transmit power constraint. In addition, the duality is also extended to multi-relay scenario with arbitrary noise. Finally, several simple general numerical examples are provided to better illustrate the effectiveness of the MIMO relay MAC-BC duality

Key words:

MIMO relay, multiuser, duality, multiple access channel, broadcast channel