Energy aware buffer aided cooperative relay selection

In this paper we evaluate an energy-aware relay selection mechanism which exploits channel state information and the availability of buffers at relays to perform flexible relaying based on a backpressure-driven optimization model. This model ensures the maximization of the cell throughput while maintains the stability of backlog queues. Performance evaluation is conducted using a System Level Simulator (SLS) which is fully compliant with IEEE 802.16m and supports various relaying scenarios. The Below Roof Top (BRT) relaying scenario is considered in this work. A holistic and flexible energy framework is implemented to capture the energy consumption of the cellular network nodes. The model maps the RF output power radiated at the antenna elements of each node including relays on the network to the total supply power of the node equipment. Two derivatives of the proposed mechanism, half-duplex and full-duplex are proposed and evaluated. Results of the two derivatives on BRT relaying scenario revealed noticeable increases for both cell throughput and system energy efficiency of the cell-edge users compared to the conventional relaying protocol and the non cooperative scheme.