Energy Harvesting Wireless Sensor Networks With Channel Estimation: Delay and Packet Loss Performance Analysis

This paper considers a single-source status monitoring system with energy harvesting in the context of applications where keeping information up-to-date is of primary interest. Specifically, a sensor node, relying on harvested energy and operating according to a harvest-then-use protocol, estimates the channel state to decide whether to perform or defer data delivery to a sink. The sink keeps track of the system status through the successfully delivered updates. To comprehensively evaluate the performance of the proposed scheme, we analytically derive the exact-closed form expressions of the packet loss probability, the age of information and the update interval metric statistics considering both constant-rate and random energy arrival processes and taking into account both the time and energy costs of sensing, transmitting and estimating the channel state. We asymptotically obtain the necessary conditions under which estimating the channel state before transmitting, despite the associated time and energy costs, allow to efficiently manage the harvested energy by avoiding erroneous transmissions and performs strictly better than transmitting without estimating the channel state. Numerical results demonstrate that in most cases, estimating the channel state before transmitting significantly reduces the packet loss probability, the age of information and the update interval of node-sink transmission.