Power Management for Motion Applications Based on Bluetooth 4.0 Low Energy Technology

• Main Author: 黃凱伶
• Other Authors: 周百祥
• Format: Others
• Language: en_US
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/52514729034679332709

碩士 === 國立清華大學 === 資訊工程學系 === 101 === Power consumption is one of the most challenging aspects in designing wearable sensors for motion tracking, as power must be saved without sacrificing sensitivity, specificity, and latency. In this thesis, we propose a vertical suite of techniques for building power-efficient wearable motion sensing systems. First, we propose a new motion recognition method based on edit distance, which is able to recognize each action over a wide range of motion amplitudes while lending itself to power management techniques at other levels. Of the three power management methods we propose for prolonging the battery life, the first is tiered hysteretic threshold, which increases sensitivity at the lower tier to wake up the next higher tier only when it deems necessary. Thus, the second power management method is adaptive thresholds, which adjusts the threshold levels automatically over time to adapt to the specific users. The third power management method exploits specific features of the wireless protocol, Bluetooth 4.0 Low Energy Technology (BLE), in integrating our tiered hysteretic and adaptive thresholding techniques to make our system energy-efficient while being directly compatible with smartmobiles without the high Rx power during idle listening. Experimental results validate the ability to recognize motions with high accuracy. These three power management methods help motion application reduce power consumption, thereby enhancing the wearability of our body sensor systems.