Dynamic voltage-frequency scaling in body area sensor networks using COTS components

Body area sensor networks (BASNs) have implicit stringent power requirements to meet battery life and form factor expectations, especially in long-term medical monitoring applications. The largest power consumer in BASNs is typically the wireless transceiver, so recent research has focused on increasing on-node signal processing to reduce the number of bits for wireless transmission. This shift increases the importance of power efficient signal processing. Given that the processing workloads and throughput requirements can change dynamically in a BASN, dynamic voltage-frequency scaling (DVFS) becomes an attractive option for providing the necessary processing rate with the minimum power. However, commercial off the shelf (COTS) components typically used in BASN nodes are not designed for DVFS. This paper characterizes the DVFS capabilities of a COTS processor commonly used on BASN nodes – the TI MSP430 – and explores the usefulness of these capabilities within the context of BASN applications.