1
Return

Fast OFDM Wi-Fi Backscatter Systems Based on Composite Channel Decoupling

delete2026-08-06
delete0
PRE
AI
Y
Yimeng Huang
C
Chenhong Cao
L
Longzhi Yuan
Y
Yuguang Fang
W
Wei Gong
DOI:10.1109/twc.2026.3719274delete
deleteOriginal
deleteOriginal request for help
deleteShare
deleteSave
Abstract

Abstract

En 中文
Improving transmission efficiency is a key objective in OFDM WiFi backscatter systems. A promising direction is sub-symbol-level tag modulation, which embeds more tag data within each OFDM symbol. However, we observe that fine-grained tag modulation is coupled with channel variation, which distorts the cascade structure between the two channels, transmitter-to-tag and tag-to-receiver, making the conventional channel estimation method in WiFi ineffective. Although recent systems have explored new channel estimation methods, their accuracy is limited and the modulation redundancy remains necessary. To address this problem, we present Fascatter, a high-throughput OFDM WiFi backscatter system that enables single-sample-level tag modulation without modulation redundancy. The key enabler is a new channel estimation method that independently estimates the two channels at per-subcarrier granularity. We construct channel observations from the LTF fields and reference symbols, and accurately solve the two channels through matrix decomposition. We further introduce polynomial smoothing and multi-symbol fine-tuning modules to improve estimation robustness. Experimental results demonstrate that the channel estimation results are close to the actual channel responses, and our method shows robust performance under a variety of complex channel conditions. In particular, Fascatter achieves a throughput of up to 15.9 Mbps, which is at least <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$3.2\times $ </tex-math></inline-formula> over state-of-the-art systems.
Keywords:
OFDM WiFi backscatter
channel estimation and equalization
single-sample-level tag modulation

Journal

IEEE Transactions on Wireless Communications cover
IEEE Transactions on Wireless Communications
IF:
10.7
Papers:
1.3W
Citations:
5.3W

Organization

C
city university of hong kong
Scholars:
4.6K
Papers: 2.7K
Citations: 2
U
University of Science and Technology of China
Scholars:
1.5W
Papers: 5.3K
Citations: 11.3W
Cited Papers

Cited Papers

Citing Papers

Citing Papers