Power-efficient streaming for mobile terminals

Wireless Network Interface (WNI) is one of the most critical components for power efficiency in multimedia streaming to mobile devices. A common strategy to save power is to switch WNI to active mode only when network activity is expected. In streaming systems, this approach is problematic because data are typically received continuously. One solution is to transmit data packets as bursts, which leaves WNI more time between bursts in standby mode. However, that subjects bursty transmission in high peak rates, which leaves it prone to congestion. In this paper, we study theoretically and empirically the impact of burst length and peak transmission rate for observed packet loss and delay characteristics as well as potential energy savings in a Wireless Local Area Network (WLAN) environment. We outline and implement a test system with adaptive burst length to achieve improved trade-off between power efficiency and congestion tolerance.