Optimal Transmission Policies for Two-User Energy Harvesting Device Networks With Limited State-of-Charge Knowledge

Abstract

This paper considers a wireless network composed of a pair of sensors powered by energy harvesting devices (EHDs), which transmit data to a receiver over a shared wireless channel. At any given time, based on the energy levels of the two rechargeable batteries of the sensors, a central controller (CC) decides on the amount of energy to be drawn from the two batteries and used for transmission. The problem considered is the maximization of the long-term average reward associated with data transmission, by optimizing the transmission strategy of the two nodes, in the case of a collision channel model and both i.i.d. and correlated energy arrivals. In addition, contrary to the traditional assumption that the amount of energy available to the sensors can be easily estimated, we derive the optimal policy in the cases where the state of charge (SOC) may not be perfectly known by the central controller, analyzing the performance degradation caused by this imperfect knowledge of the SOC. For this second scenario, supposing that the CC is only aware that each SOC is “LOW” or “HIGH,” we show that the impact of imperfect knowledge decreases with the two battery capacities and is negligible in most cases of practical interest

On optimal policies in full-duplex wireless powered communication networks

“…In order to characterize the maximum achievable throughput by the system, we assume that the transmission data queues are always non empty, i.e., D 1 and D 2 always have data to transmit (this assumption can be extended as in [34]). Thus, the energy level of D i is updated according to (the energy gathered in a given slot can be exploited only in later time slots)…”

Power allocation and relay selection for energy efficient cooperation in wireless sensor networks with energy harvesting

“…is emerging. Because of its intrinsic capability of self-sustainability, a lot of researches have been done on it; many of them focus on the high-efficient energy utilization [1][2][3]. As for this energy harvesting-wireless sensor networks (EH-WSN), the main challenge is to maximize its working performance under energy harvesting constraints, so studies on the MAC protocol, routing protocol, and cross layer optimization also obtain lots of achievements [4][5][6][7][8][9][10].…”

Joint optimal placement, routing, and energy allocation in wireless sensor networks with a shared energy harvesting module

“…Moreover, if used wisely, the EH-WSN would never break down, except for hardware failure. 8–11 However, it is important to note that because of the stochastic nature of EH procedures, the harvested energy cannot transfer in a steady and uninterrupted fashion. Thus, a method for accurate energy allocation is essential for the EH-WSN system.…”