CDIP: Channel-Aware Dynamic Window Protocol for Energy-Efficient IoT Communications

Abstract

Energy efficiency plays a critical role in widespread deployability of Internet of Things (IoT) applications. While there have been some prior studies on channel-adaptive communication strategies, these approaches do not fully exploit the channel knowledge on increasing energy efficiency in link-layer communications. In this paper, we consider point-to-point IoT communication over wireless channel. We propose a generalized channel-aware link-layer communication strategy that exploits temporal variations of the communication channel to improve on energy efficiency. Specifically, we propose a generalized channel dependent communication strategy that just depends on rate of variation of the channel and not on its underlying fading distribution. We utilize this generalized information on channel state variation in dynamically deciding on the transmission and waiting windows in link-layer transmission, which gives significant benefits in terms of system throughput as well as energy efficiency by optimally using the good channel states and avoiding redundant transmission of acknowledgements. Our analytical claims and numerical results are verified through extensive simulations. Our numerical results further demonstrate that, the proposed dynamic window protocol offers a significant gain of about 40% in terms of data throughput and about 41% in terms of energy efficiency in comparison to its nearest competitive existing benchmark scheme.