Adaptive-Buffer Power Save Mechanism for Mobile Multimedia Streaming

Wireless networks are becoming a part of everyday life for many people. When a mobile device has wireless LAN capability, multimedia content can be streamed over a wireless network to that device. However, a major disadvantage of all mobile devices is their limited battery lifetime. Multimedia streaming puts extra pressure on the battery, causing it to discharge faster. In some cases, streaming tasks cannot be completed purely because the battery of the device becomes fully discharged, which causes significant user dissatisfaction. Consequently, it is necessary to devise mechanisms to enable longer battery lifetime in order to support complex applications such as those involving mobile multimedia streaming. This paper proposes an adaptive-buffer power save mechanism (AB-PSM) for increasing the battery life of mobile devices during multimedia streaming. This increase is achieved by controlling how and when data is sent over a wireless LAN. AB-PSM introduces an additional buffer which hides data from the station it is intended for, allowing it to return to sleep and consequently saving power. Data is eventually delivered in one of the station´s following attempts to receive it. Tests involving AB-PSM have been performed and show good results in terms of significant increases in battery lifetime. The comparison between AB-PSM and the IEEE 802.11 legacy power save mechanism shows important increases in battery lifetime of more than 100%.