Design of 100 muW wireless sensor nodes on energy scavengers for biomedical monitoring

Wireless sensor nodes span a wide range of applications. This paper focuses on the biomedical area, more specifically on healthcare monitoring applications. Power dissipation is the dominant design constraint in this domain. This paper shows the different steps to develop a digital signal processing architecture for a single channel electrocardiogram application, which is used as an application example. We aim for less than 100μW power consumption as that is the power energy scavengers can deliver. We follow a bottleneck-driven approach, the following steps are applied: first the algorithm is tuned to the target processor, then coarse grained clock-gating is applied, next the static as well as the dynamic dissipation of the digital processor is reduced by tuning the core to the target domain. The impact of each step is quantified. A solution of around 11μW is possible for both radio and DSP with the electrocardiogram algorithm.