Radiofrequency Energy Harvesting for Wearable Sensors
Borges, Luis M.
; CHÁVEZ-SANTIAGO, R.
Velez, F. J.
Healthcare Technology Letters Vol. 2, Nº 1, pp. 22 - 27, February, 2015.
ISSN (print): 2053-3713
Journal Impact Factor: (in 2014)
Digital Object Identifier: 10.1049/htl.2014.0096
The use of wearable biomedical sensors for the continuous monitoring of physiological signals will facilitate the involvement of the patients in the prevention and management of chronic diseases. The fabrication of small biomedical sensors transmitting wirelessly physiological data is possible as a result of the tremendous advances in ultra-low power electronics and radio communications. However, the widespread adoption of these devices depends very much on their ability to operate for long periods of time without the need to frequently change, recharge, or even use batteries. In this context, energy harvesting is the disruptive technology that can pave the road toward the massive utilization of wireless wearable sensors for patient self-monitoring and daily healthcare. Radiofrequency transmissions from commercial telecommunication networks represent reliable ambient energy that can be harvested as they are ubiquitous in urban and suburban areas. This letter showcases the state-of-the-art in radiofrequency energy harvesting for wearable biomedical sensors specifically targeting the GSM 900/1800 cellular and 700 MHz DTT networks as ambient RF energy sources. We also present guidelines for the choice of the number of stages for the RF energy harvester, depending on the requirements from the embedded system we want to power supply, which is useful for other researchers that work in the same area. Our recent advances toward the development of an efficient radiofrequency energy harvester and storing system are presented and thoroughly discussed too.