Medium Access Control Protocols for Wireless Sensor Networks with Energy Harvesting

Abstract

The design of Medium Access Control (MAC) protocols for wireless sensor networks (WSNs) has been conventionally tackled by assuming battery-powered devices and by adopting the network lifetime as the main performance criterion. While WSNs operated by energy-harvesting (EH) devices are not limited by network lifetime, they pose new design challenges due to the uncertain amount of harvestable energy. Novel design criteria are thus required to capture the trade-offs between the potentially infinite network lifetime and the uncertain energy availability. This paper addresses the analysis and design of WSNs with EH devices by focusing on conventional MAC protocols, namely TDMA, Framed-ALOHA (FA) and Dynamic-FA (DFA), and by accounting for the performance trade-offs and design issues arising due to EH. A novel metric, referred to as delivery probability, is introduced to measure the capability of a MAC protocol to deliver the measure of any sensor in the network to the intended destination (or fusion center, FC). The interplay between delivery efficiency and time efficiency (i.e., the data collection rate at the FC), is investigated analytically using Markov models. Numerical results validate the analysis and emphasize the critical importance of accounting for both delivery probability and time efficiency in the design of EH-WSNs. Index TermsWireless sensor networks, multiaccess communication, energy harvesting, dynamic framed ALOHA. ). U. Spagnolini is with Politecnico di Milano. O. Simeone is with the CWCSPR, NJIT. Recent advances in low-power electronics and energy-harvesting (EH) technologies enable the design of self-sustained devices that collect part, or all, of the needed energy from the surrounding environment. Several systems can take advantage of EH technologies, ranging from portable devices to wireless sensor networks (WSNs) [1]. However, EH devices open new design issues that are different from conventional battery-powered (BP) systems [2], where the main concern is the network lifetime [3]. In fact, EH potentially allows for perpetual operation of the network, but it might not guarantee short-term activities due to temporary energy shortages [2].This calls for the development of energy management techniques tailored to the EH dynamics. While such techniques have been mostly studied at a single-device level [4], in wireless scenarioswhere multiple EH devices interact with each other, the design of EH-aware solutions needs to account for a system-level approach [5] [6]. This is the motivation of this work.In this paper, we focus on system-level design considerations for WSNs operated by EHcapable devices. In particular, we address the analysis and design of medium access control (MAC) protocols for single-hop WSNs (see Fig. 1) where a fusion center (FC) collects data from sensors in its surrounding. Specifically, we investigate how performance and design of MAC protocols routinely used in WSNs, such as TDMA [7], Framed-ALOHA (FA) and Dynamic-FA (DFA) [8], are influenced by the discontinuous energy availabi...

Application of reinforcement learning to medium access control for wireless sensor networks

“…The sustainable energy supply and temporary energy shortages bring new concerns for MAC protocol research. The work in [52] proposes dynamic-framed-ALOHA (DFA) for WSNs with EH devices which aim to improve the packet delivery probability.…”

“…The sink schedules extended frames for nodes in the backlog set to transmit their data. The size of the backlog set is estimated at the sink by using the distribution of the energy storage and prior channel outcomes without obtaining any information from nodes in the network [52]. DFA has low overheads and achieves good delivery probability.…”

RF-MAC: A Medium Access Control Protocol for Re-Chargeable Sensor Networks Powered by Wireless Energy Harvesting

“…However, this protocol requires a strict centralized base station control and relies on out-of-band RF power transfer. In [7], conventional MAC protocols, such as the classical TDMA and variants of ALOHA are evaluated assuming out-of-band RF transfer.…”

Controlled sampling using an energy harvesting sensor

“…However, the vast majority of these works focus on the communications aspect and do not consider sensing or sampling, much less controlled sensing or sampling. These literature have covered many aspects of communications with energy harvesting including source and channel coding [2], power control [3], power allocation [4], scheduling [5], routing [6], multiple access [7] and throughput maximization or delay constraints [8]. Information theoretic aspects are studied in [9] and [10].…”