The Approximate Capacity of the MIMO Relay Channel
Xianglan Jin, Young-Han Kim · IEEE Transactions on Information Theory · 2016
Capacity bounds are studied for the multiple-antenna complex Gaussian relay channel with t1transmitting antennas at the sender, r2receiving and t2transmitting antennas at the relay, and r3receiving antennas at the receiver. It is shown that the partial decode-forward coding scheme achieves within (t1,r2) 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 (t1+ t2, r3) + r2bits is shown to be achieved by the compress-forward coding scheme. The corresponding results for time-division half-duplex relay channels are also established.