GuardRider: Towards Sustainable Backscattering System over WiFi in the Wild

TL;DR

GuardRider is a novel WiFi backscatter system that uses an optimization algorithm for RS codes, enabling reliable and adaptive low-power communication in unpredictable WiFi environments, verified through hardware prototypes and experiments.

Contribution

It introduces an RS code optimization algorithm tailored to WiFi traffic patterns, improving backscatter reliability and simplicity in wild conditions.

Findings

Significant reduction in bit error rate and frame error rate.

Achieved around 99% error rate reduction in field experiments.

Demonstrated practical hardware implementation with FPGA.

Abstract

The WiFi backscatter communications offer ultra-low power and ubiquitous connections for IoT systems. Caused by the intermittent-nature of the WiFi traffics, state-of-the-art WiFi backscatter communications are not reliable for backscatter link or simple for tag to do adaptive transmission. In order to build sustainable (reliable and simple) WiFi backscatter communications, we present GuardRider, a WiFi backscatter system that enables backscatter communications riding on WiFi signals in the wild. The key contribution of GuardRider is an optimization algorithm of designing RS codes to follow the statistical knowledge of WiFi traffics and adjust backscatter transmission. With GuardRider, the reliable baskscatter link is guaranteed and a backscatter tag is able to adaptively transmit information without heavily listening the excitation channel. We built a hardware prototype of GuardRider using a customized tag with FPGA implementation. Both the simulations and field experiments verify that GuardRider could achieve a notably gains in bit error rate and frame error rate, which are hundredfold reduction in simulations and around 99% in filed experiments.