Delay-differentiated scheduling in a randomized MIMO relay network

The paper considers a randomized multiuser MIMO relay network with M sources. Each source and the destination node have multiple transmit/receive antennas. The R relay nodes have only one antenna transmit and receive antenna, and they pseudo-randomly vary the transmission signal, and generate a time-varying MIMO channel to the destination node. The destination schedules the transmissions of delay-differentiated services of the M sources. Both opportunistic and centralized scheduling policies are considered and it is seen that with both schedulers the resulting capacity is similar, and that delay differentiation is effective. Increasing the number of transmit and receive antennas reduces the scheduling gain considerably.