Energy Efficient Communication in Multi-Radio PANs

Dynamic switching between multiple radio interfaces has been shown to reduce power consumption and increase battery lifetime in mobile devices. In this paper, we first present empirical data measured on Sony UMPC and iPhone in a personal area network (PAN) environment to emphasize the need for dynamic multi-radio switching. We then present a collaborative power management architecture and design protocols that balance between performance and energy efficiency by exploiting energy characteristics of different radios. A prototype that implements the protocols is developed on a laptop and evaluated on a PAN testbed. Empirical results using typical MP3 workloads show a 32% reduction in the total platform energy consumption on the laptop and 72% reduction in energy consumed due to radio activity. Moreover, analysis shows that for UMPC and iPhone, potentially 2 to 4- fold reductions on platform energy consumed by radio activities could be achieved.