Optimal Power Allocation for Full-Duplex Cooperative Multiple Access

Multiple access schemes in which the transmitting nodes are allowed to cooperate have the potential to provide higher quality of service than conventional schemes. In the class of pairwise cooperative multiple access schemes in which channel state information is available at the transmitters, the allocation of transmission power plays a key role in the realization of these quality of service gains. Unfortunately, the natural formulation of the power allocation problem for full-duplex cooperative schemes is not convex, but it is shown herein that this non-convex formulation can be simplified and re-cast in a convex form. In fact, in most scenarios a closed form expression for the optimal power allocation for each point on the boundary of an achievable rate region can be obtained.