With mobile video increasingly becoming an important driver of mobile device usage, the battery consumption of mobile devices will be dominated by video delivery and playback. In this paper, we develop battery efficient video download techniques that vary video download rate dynamically, including stopping video download at times, depending on mobile device buffer levels and the channel conditions experienced, to maximize battery life while ensuring no degradation in user experience. The proposed dynamic download rate adaptation techniques enable the base station to adapt the MIMO transceiver configurations to reduce battery load required by MIMO components on the mobile device. In order to further enhance battery life, we propose to utilize video bit rate adaptation, in addition to download rate adaptation and MIMO reconfiguration.
The proposed battery aware bit rate adaptation techniques take into account the mobile device battery and buffer levels, and network load and channel conditions experienced, to maximize battery lifetime (hence video viewing time) while ensuring desired level of video experience (measured in terms of video quality and stalls experienced). We propose a new metric termed "video experience longevity (VEL)" which quantifies theperformance of the proposed bit rate adaptation techniques in terms of video viewing time and video experience. Extensive experiments conducted under variable channel conditions and network load demonstrate that the proposed battery aware video delivery techniques can significantly outperform other video delivery techniques in terms of battery lifetime and VEL metric (for bit rate adaptation techniques) while ensuring desired level of video experience.