Power Estimation using the Hogthrob Prototype Platform

This thesis is placed in the context of the Hogthrob project, whose goal is to monitor key aspects of a sow lifecycle using a sensor network. A sensor network is defined as a collection of sensor nodes equipped with processing and communication capabilities. So far, sensor nodes have been designed using commonly available components chosen to accommodate the needs of a general purpose sensor network application. In contrast, we choose to follow a holistic approach and allow specific application requirements to dictate the relevant decisions at all levels of the sensor network design, including both hardware and software. We need to consider a very large design space: e.g., what micro-controller to use? what radio to use? Do we need hardware accelerators? How to best support duty cycling? The key problem is how to explore this design space: How to evaluate the impact of a design decisions on the application in terms of functionality and performance? This thesis attacks this problem. We first describe the application requirements in the context of Hogthrob. In the first part of this thesis, we analyze two prominent sensor network applications already deployed. We review the sensor nodes available today and discuss their relevance in the context of Hoghtrob. We focus on the issue of power consumption which is critical and will thus drive many of our design decisions. We discuss how to estimate power consumption in a sensor network. In the second part, we describe how to explore the design space for the Hogthrob application. We describe the design of the Hoghtrob sensor node prototype and we detail how to estimate power consumption using this platform. Finally, we discuss as future work how to apply this power estimation technique to explore the design space for the Hogthrob sensor nodes on a chip.