WISPCam: An RF-Powered Smart Camera for Machine Vision Applications

Sustained exponential improvements in the energy efficiency of microelectronics has recently enabled us to build battery-free camera systems that are powered entirely by propagating radio waves. This paper describes primitive machine vision applications built using this highly constrained, battery-free camera system. After describing the WISPCam system and its constraints, we show how to leverage onboard computation capabilities to compress data transmit as much as possible. Then we demonstrate application of WISPCam for face detection/recognition. To that end, we use WISPCam to capture (relatively) high resolution images of faces, without ever capturing a full frame at high resolution. This example application illustrates the issues that arise in partitioning a demanding vision application across mobile hardware that is highly constrained in power, storage, computation, and communication.