Orthcatter: High-throughput In-band OFDM Backscatter with Over-the-Air Code Division

Explore a cutting-edge conference talk on Orthcatter, a groundbreaking in-band OFDM backscatter system that achieves higher throughput while consuming fewer spectrum resources. Delve into the innovative over-the-air code division technique that enables cancellation of co-channel interferences, addressing the core challenge of in-band backscatter communication. Learn about the unique approach of constructing quasi-orthogonal backscatter codewords by swapping subcarriers of excitation OFDM symbols and implementing this design passively with a double side-band symbol construction method. Discover the two-step interference cancellation scheme that significantly improves reliability. Examine the impressive prototype test results, showcasing Orthcatter's ability to achieve a throughput of 248kbps and a BER of 10^-4 under OFDM WiFi exciter, surpassing state-of-the-art in-band and side-band backscatter systems. Gain insights into the system's enhanced exciter-to-tag communication range, which is three times that of prior OFDM backscatter systems.

NSDI '24 - Orthcatter: High-throughput In-band OFDM Backscatter with Over-the-Air Code Division