Transmission Power Control in Body Area Sensor Networks for Healthcare Monitoring

TLDR

The study examines how dynamic radio transmit power control can extend the battery life of body‑wearable sensors for continuous health monitoring. The authors benchmark energy savings versus reliability, propose real‑time adaptive power‑control schemes based on receiver feedback, and implement them on a MicaZ mote and a Toumaz ultra‑low‑power platform. Empirical results show that link quality fluctuates rapidly, making fixed power either wasteful or unreliable; the proposed schemes achieve the benchmarked energy‑reliability trade‑off, and preliminary deployments on MicaZ and Toumaz platforms confirm the expected savings and performance gains.

Abstract

This paper investigates the opportunities and challenges in the use of dynamic radio transmit power control for prolonging the lifetime of body-wearable sensor devices used in continuous health monitoring. We first present extensive empirical evidence that the wireless link quality can change rapidly in body area networks, and a fixed transmit power results in either wasted energy (when the link is good) or low reliability (when the link is bad). We quantify the potential gains of dynamic power control in body-worn devices by benchmarking off-line the energy savings achievable for a given level of reliability.We then propose a class of schemes feasible for practical implementation that adapt transmit power in real-time based on feedback information from the receiver. We profile their performance against the offline benchmark, and provide guidelines on how the parameters can be tuned to achieve the desired trade-off between energy savings and reliability within the chosen operating environment. Finally, we implement and profile our scheme on a MicaZ mote based platform, and also report preliminary results from the ultra-low-power integrated healthcare monitoring platform we are developing at Toumaz Technology.