MIMO relay channel

The approximate capacity of the MIMO relay channel

Xianglan Jin and Young-Han Kim

IEEE Transactions on Information Theory, vol. 63, no. 2, pp. 1167–1176, February 2017.
Preliminary results appeared in Proceedings of the IEEE International Symposium on Information Theory, pp. 2102–2106, Honolulu, Hawaii, July 2014.
IEEE AbstractPlus.

Capacity bounds are studied for the multiple-antenna complex Gaussian relay channel with t_1 transmitting antennas at the sender, r_2 receiving and t_2 transmitting antennas at the relay, and r_3 receiving antennas at the receiver. It is shown that the partial decode–forward coding scheme achieves within min(t_1,r_2) bits from the cutset bound and at least one half of the cutset bound, establishing a good approximate characterization of the capacity. A similar additive gap of min(t_1+t_2,r_3)+r_2 bits is shown to be achieved by the compress–forward coding scheme. The corresponding results for time-division half-duplex relay channels are also established.