Wi-fi backscatter

TLDR

RF‑powered computers compute and communicate solely from harvested RF energy, but existing solutions require a dedicated gateway to access the Internet. We present Wi‑Fi Backscatter, a novel system that bridges RF‑powered devices with the Internet. By reusing existing Wi‑Fi infrastructure, we built a hardware prototype that demonstrates the first communication link between an RF‑powered device and commodity Wi‑Fi devices. Using off‑the‑shelf Wi‑Fi hardware, we achieved communication rates up to 1 kbps over ranges of up to 2.1 m, suggesting that this capability could enable rapid deployment of RF‑powered devices and ubiquitous connectivity through nearby Wi‑Fi‑enabled mobile devices.

Abstract

RF-powered computers are small devices that compute and communicate using only the power that they harvest from RF signals. While existing technologies have harvested power from ambient RF sources (e.g., TV broadcasts), they require a dedicated gateway (like an RFID reader) for Internet connectivity. We present Wi-Fi Backscatter, a novel communication system that bridges RF-powered devices with the Internet. Specifically, we show that it is possible to reuse existing Wi-Fi infrastructure to provide Internet connectivity to RF-powered devices. To show Wi-Fi Backscatter's feasibility, we build a hardware prototype and demonstrate the first communication link between an RF-powered device and commodity Wi-Fi devices. We use off-the-shelf Wi-Fi devices including Intel Wi-Fi cards, Linksys Routers, and our organization's Wi-Fi infrastructure, and achieve communication rates of up to 1 kbps and ranges of up to 2.1 meters. We believe that this new capability can pave the way for the rapid deployment and adoption of RF-powered devices and achieve ubiquitous connectivity via nearby mobile devices that are Wi-Fi enabled.