Energy implication of various VoIP codecs in portable devices

Current portable devices e.g. cell phones, PDA´s and laptops are mainly Wi-Fi capable. Users can make efficient use of these devices by running various applications. Among these, the Voice over Internet Protocol (VoIP) application is very popular. As new models of these devices emerge, they are increasingly power hungry in terms of processing and communication. As a result, battery lifetime is one of the most critical performance parameters. This paper presents experimental studies on the energy depletion characteristics of VoIP applications when using various codecs in an IEEE 802.11 Wireless LAN setting. The effect of high, medium and low bandwidth codecs on battery life is studied and an adaptive algorithm is proposed that switches codecs in the middle of an active call based on remaining battery life.