Protocol Stack and System Software Optimization for Energy Efficient Wireless Embedded Systems

The widespread use of battery-operated embedded systems with wireless communication capabilities (e.g., PDAs, palmtop computers, cell phones, networked sensors, etc.) has generated significant research interest in energy efficient design techniques. This paper provides an overview of techniques developed at University of Bologna, in cooperation with several industrial partners, for battery lifetime optimization by means of an energy aware usage of system communication and computation resources. We distinguish between techniques aiming at minimizing energy dissipation of the wireless network interface and those aiming at saving energy while targeting the whole system, for those cases where a decrease of network adapter energy might be erased by an increase of system energy. Measurements on real experimental settings provided energy savings ranging from 20 to 70% with respect to the use of stateof-the-art MAC layer power management techniques available inmost commercial wireless network adapters.