Optimized capacity bounds for the MIMO relay channel

This paper addresses the optimization of upper and lower bounds on the capacity of the multiple-input multiple-output (MIMO) relay channel. In particular, we show that evaluating the cut-set bound and the maximal achievable decode-and-forward rate is equivalent to solving convex optimization problems, where we assume that perfect channel state information is available at all nodes. Our optimized bounds thus improve on previously published results while they can be efficiently determined using convex programming techniques at the same time.