Device-free human activity recognition plays a pivotal role in wireless sensing. However, current systems often fail to accommodate signal transmission through walls or necessitate dedicated noise removal algorithms. To overcome these limitations, we introduce TRTAR: a device-free passive human activity recognition system integrated with a transmissive reconfigurable intelligent surface (RIS). TRTAR eliminates the necessity for dedicated devices or noise removal algorithms, while specifically addressing signal propagation through walls. Unlike existing approaches, TRTAR solely employs a transmissive RIS at the transmitter or receiver without modifying the inherent hardware structure. Experimental results demonstrate that TRTAR attains an average accuracy of 98.13% when signals traverse concrete walls.
@article{arxiv.2401.05170,
title = {TRTAR: Transmissive RIS-assisted Through-the-wall Human Activity Recognition},
author = {Junshuo Liu and Yunlong Huang and Jianan Zhang and Rujing Xiong and Robert Caiming Qiu},
journal= {arXiv preprint arXiv:2401.05170},
year = {2024}
}