Bursting: Increasing Energy Efficiency of Erasure-Coded Data in Animal-Borne Sensor Networks

Observing the (social) behavior of animals and especially bats contributes to improved epidemic forecasts and improved protection of rare or endangered species. For this task, animal-borne sensor nodes are powerful tools since they allow collecting more information at less influence to the species compared to traditional radio telemetry. However, as bats are inherently small vertebrates, a strict weight limit of 2 g is dictated for attached sensor nodes. To acquire enough data, the sensor nodes must achieve a runtime of at least two weeks, which demands a rigorous energy management. As the data transmission is the most energy hungry task, minimizing the energy demand in this segment is a key to achieve the desired runtimes. In this paper we present a novel technique that enables bursts of erasure coded data without sacrificing reliability (in a wildlife setting). To keep data losses at a minimum, our approach exploits the characteristics of the erasure channel and combines encoded packets in smart way. We evaluated this approach extensively with experiments, field tests and a theoretical analysis. The results show a decreased energy demand by 30.177 % to 36.951 % while the data rate is increased up to a factor of 4 at the same time.