QoS driven power allocation over full-duplex wireless links

Abstract

We propose the quality-of-service (QoS) driven power allocation scheme for full-duplex wireless links. By integrating information theory with the principle of effective capacity, we build two models — local transmit power related self-interference (LTPRS) model and local transmit power unrelated self-interference (LTPUS) model to analyze the full-duplex transmission, respectively. In the LTPRS model, self-interference directly corresponds to the level of local transmit power. In the LTPUS model, self-interference does not directly relate to the level of local transmit power. For both of these two models, we derive the optimal power allocation schemes, which aim at maximizing the system throughput subject to a given delay QoS constraint, over bidirectional wireless links with full-duplex transmission. The analyses and numerical results verify that our proposed power allocation scheme can efficiently support diverse QoS requirement over full-duplex wireless links. For LTPRS model, the optimal power allocation scheme converges to a constant power scheme when the QoS constraint gets very loose and the optimal power allocation scheme reduces to the channel inversion scheme when the QoS constraint becomes very stringent. For LTPUS model, the optimal power allocation scheme converges to the the water-filling scheme when the QoS constraint gets very loose and the optimal power allocation scheme reduces to the channel inversion scheme when the QoS constraint becomes very stringent.