SlimWiFi: Ultra-Low-Power IoT Radio Architecture Enabled by Asymmetric Communication

To communicate with existing wireless infrastructures such as Wi-Fi, an Internet of Things (IoT) radio device needs to adopt a compatible PHY layer which entails sophisticated hardware and high power consumption. This paper breaks the tension for the first time through a system called SlimWiFi. A SlimWiFi radio actively transmits on-off keying (OOK) modulated signals. But through a novel asymmetric communication scheme, it can be directly decoded by off-the-shelf Wi-Fi devices. With this measure, SlimWiFi radically simplifies the radio architecture, evading power hungry components such as data converters and high-stability carrier generators. In addition, it can cut the transmit power by around 18 dB, while keeping a similar link budget as standard Wi-Fi. We have implemented SlimWiFi through PCB prototype and IC tape-out. Our experiments demonstrate that SlimWiFi can reach around 100 kbps goodput at up to 60 m, while reducing power consumption by around 3 orders of magnitude compared to a standard Wi-Fi transmitter.