Optimal Resource Allocation and Relay Selection for Self-Sustainable Relaying Networks

In this paper, we consider a wireless co-operative network involving two transceiver nodes whose communication is aided by energy-constrained two-way relay nodes. Each relay node employs a non-regenerative relaying protocol. The transceiver nodes can simultaneously transmit information and energy and the relay nodes harvest the energy from the received signal and use the harvested energy to amplify and retransmit the signal to the destination. The relay nodes implement power-splitting (PS) scheme to apportion the received signal power to the information processing and the energy harvesting units. We address the problem of sum-rate maximization under constraints on total transmit power and harvested energy. We propose an optimal resource allocation and relay selection scheme as well as a reduced-complexity sub-optimal scheme. The performance of the proposed solutions are illustrated by numerical simulations.