Server Controlled Power Management for Wireless Portable Devices

Acquaviva, Andrea ; Simunic, Tajana ; Deolalikar, Vinay ; Roy, Sumit

HP Development Company

关键词: low-power;    wireless;    multimedia;   

RP-ID  :  HPL-2003-82

学科分类：计算机科学（综合）

美国|英语

来源: HP Labs

【 摘 要 】

In this report we present a new power management infrastructure developed for the Linux operating system release running on the HP's SmartBadge4 wearable computer. Based on this infrastructure, we implemented a new methodology for optimizing the energy consumption of wireless portable devices. The server knowledge of the workload is exploited to efficiently drive the wireless interface of the client during data transfer over the wireless channel. We tested our methodology on HP's SmartBadgeIV wearable device running a HP's MPEG4 streaming video application. Using our technique we measured energy savings of more than 67% when no power management is used on the WLAN interface. In addition, we save as much as 50% of energy with respect to using power management implemented as a part of the 802.11b standard. All of the energy savings are obtained with no performance loss on the video playback.