GVU Technical Report Number: GIT-GVU-09-07

Title: Using In-Home Power Lines to Extend the Range of Low-Power Wireless Devices

Authors: Erich P. Stuntebeck, Thomas Robertson, Gregory D. Abowd, Shwetak N. Patel

Abstract: This work demonstrates the feasibility of using existing in-home electrical wiring to extend the operational range of certain wireless devices. Specifically, a wireless keyboard operating at 27 MHz, which has an operational range of 1.5 – 2 meters on its own, was extended to work throughout a 3-story 4,000 square foot / 371 square meter home by coupling the antenna port on its receiver to the power lines. Coupling between the keyboard and the power lines occurred over the air, and coupling at the receiver was accomplished capacitively by simply wrapping a wire connected to the receiver’s antenna port several times around a standard electrical device cord plugged into a wall socket. This phenomenon of the power line as a communications infrastructure for cheap and low-power wireless devices has a variety of interesting potential avenues of research in the home.