Sustainable medium access control: Implementation and evaluation of ODMAC

Harvesting small-scale ambient energy constitutes a promising source of power for wireless embedded devices. Due to the unpredictable nature of the harvested energy, adaptive radio duty cycling can lead to a long-term sustainable operation. In energy constrained conditions, very low duty cycles are vital to guarantee the sustainability of the system; whereas, in the opposite case, the system should use the energy surplus to increase the application performance. In this paper, we implement and evaluate On-Demand MAC (ODMAC), the first receiver-initiated MAC protocol specifically designed for energy harvesting applications. In particular, we provide a basic yet fully operational implementation of ODMAC for the Texas Instruments´ MSP430 microprocessor family. Furthermore, we verify the theoretical results of our previous work by achieving sustainable operation of an energy harvesting node in various cases of energy input using a real test-bed.