Abstract
In this paper, we seek answer to the question: can a wireless sensing system with energy harvesting power supplies perform as well as the one with conventional power supplies? Conventional sensing systems with deterministic energy sources usually employ uniform sampling. However, due to the stochastic nature of the energy harvested from the ambient environment, uniform sampling is usually infeasible for energy harvesting sensing systems. We thus propose a simple best-effort sensing scheme, which defines a set of equally spaced candidate sensing instants. At a given candidate sensing instant, the sensor will perform sensing if there is sufficient energy available, and it will remain silent otherwise. It is analytically shown that the percentage of silent candidate sensing instants goes to zero as time increases, if and only if the average energy harvesting rate is no less than the average energy consumption rate. Therefore, the difference between the best-effort sensing policy and the uniform sensing policy diminishes as time evolves. The theoretical results are then used to guide the design of a practical sensing system that monitors a time-varying event. Both analysis and simulations show that the energy harvesting system with the best-effort sensing scheme can asymptotically achieve the same mean squared error (MSE) performance as the one with uniform sensing and deterministic energy sources. Therefore, we provide a positive answer to the question by establishing the asymptotic equivalence between stochastic and deterministic energy sources, from both theoretical and practical aspects.
Highlights
Wireless sensing systems, such as structure health monitoring, biomedical sensing, and environment monitoring, are usually expected to operate uninterruptedly and autonomously over years or decades under extremely stringent energy constraints
It will be shown through both theoretical analysis and simulations that the mean squared error (MSE) performance of the energy harvesting sensing system asymptotically approaches that of a conventional sensing system with uniform sensing as time goes to infinity
6 Conclusions The asymptotic equivalence between stochastic and deterministic energy sources has been demonstrated through both theoretical analysis and practical examples
Summary
Wireless sensing systems, such as structure health monitoring, biomedical sensing, and environment monitoring, are usually expected to operate uninterruptedly and autonomously over years or decades under extremely stringent energy constraints. Due to the randomness in the energy arrival process, uniform sampling might be infeasible in energy harvesting systems given that there might not be sufficient energy to perform sensing operations at certain time periods. Guided by the theoretical results, we develop optimum sensing and detection schemes for a practical energy harvesting sensing system used to monitor a time-varying event It will be shown through both theoretical analysis and simulations that the MSE performance of the energy harvesting sensing system asymptotically approaches that of a conventional sensing system with uniform sensing as time goes to infinity. Due to the inherent randomness of the energy harvesting process, uniform sampling might be infeasible given that there might not be sufficient energy to perform sensing operations at certain time periods. The performance of uniform sampling with conventional power supply can serve as a lower bound for systems with energy harvesting devices
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: EURASIP Journal on Wireless Communications and Networking
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
