Energy efficient subchannel pairing for buffer-aided multi-relay MIMO-OFDM networks

In this paper, we consider the buffer-aided multi-relay MIMO-OFDM networks and propose a joint space-time-frequency subchannel pairing scheme, in which subchannels of the source to relay links and relay to the destination links are paired in time, frequency, and space domain (TPFPSP) simultaneously. TPFPSP scheme can increase the equivalent channel gains between source and destination. We derive new expressions for the energy efficiency, the system capacity and the outage probability to examine the performance of TPFPSP scheme. Our analytical and numerical results outline that this TPFPSP scheme brings higher capacity, energy efficiency and better outage probability performance to our system. This work reported here provides detailed insights into the design of new subchannel pairing scheme, which achieves full diversity in space, time and frequency domains.