Throughput Maximization for Decode-and-Forward Relay Channels with Non-Ideal Circuit Power

This paper studies the throughput maximization problem for a three-node relay channel with direct link and non-ideal circuit power. The relay operates in a half- duplex manner, and the decode-and-forward (DF) relaying is adopted. Considering the extra power consumption by the circuits, the optimal power allocations over infinite time horizon are investigated. First, two special scenarios, i.e., the direct link transmission (only use the direct link to transmit) and the relay assisted transmission (the source and the relay transmit with equal probability), are studied. By solving two non-convex optimization problems, the solutions show that the source and the relay transmit with certain probability, which is determined by the average power budgets, circuit power consumptions, and channel gains. Then, based on the above results, the optimal power allocation for the original throughput maximization problem is investigated, which is shown to be a mixed transmission scheme between the direct link transmission and the relay assisted transmission.