TY - JOUR
T1 - Efficient Subcarrier-Level OFDM Backscatter Communications
AU - Du, Caihui
AU - Yu, Jihong
AU - Yan, Zhenyu
AU - Ren, Ju
AU - Zhang, Rongrong
AU - Li, Yun
N1 - Publisher Copyright:
© 2002-2012 IEEE.
PY - 2025
Y1 - 2025
N2 - Most of the existing OFDM backscatter systems adopt phase-modulated schemes to embed tag data, suffering from symbol-level modulation limitation, heavy synchronization accuracy reliance, and small tolerability to symbol time offset (STO) / carrier frequency (CFO) offset. We introduce SubScatter, the first subcarrier-level frequency-modulated OFDM backscatter which is able to tolerate bigger synchronization errors, STO, and CFO. The unique feature of SubScatter is our subcarrier shift keying (SSK) modulation. This method pushes the modulation granularity to the subcarrier by encoding and mapping tag data into different subcarrier patterns. We also design a tandem frequency shift (TFS) scheme that enables SSK with low cost and low power. Furthermore, we design SubScatter+ that shows these advantages while providing an even higher throughput without requiring more subcarrier patterns. We prototype and test SubScatter and SubScatter+, and the results show that our systems outperforms prior works in terms of effectiveness and robustness. Specifically, SubScatter has 743kbps throughput that is 3.1 times and 14.9 times higher than RapidRider and MOXcatter, respectively. It also has a lower BER under noise and interferences which is over 6 times better than RapidRider or MOXcatter. Moreover, our proposed SubScatter+ could increase the throughput of SubScatter by 30%.
AB - Most of the existing OFDM backscatter systems adopt phase-modulated schemes to embed tag data, suffering from symbol-level modulation limitation, heavy synchronization accuracy reliance, and small tolerability to symbol time offset (STO) / carrier frequency (CFO) offset. We introduce SubScatter, the first subcarrier-level frequency-modulated OFDM backscatter which is able to tolerate bigger synchronization errors, STO, and CFO. The unique feature of SubScatter is our subcarrier shift keying (SSK) modulation. This method pushes the modulation granularity to the subcarrier by encoding and mapping tag data into different subcarrier patterns. We also design a tandem frequency shift (TFS) scheme that enables SSK with low cost and low power. Furthermore, we design SubScatter+ that shows these advantages while providing an even higher throughput without requiring more subcarrier patterns. We prototype and test SubScatter and SubScatter+, and the results show that our systems outperforms prior works in terms of effectiveness and robustness. Specifically, SubScatter has 743kbps throughput that is 3.1 times and 14.9 times higher than RapidRider and MOXcatter, respectively. It also has a lower BER under noise and interferences which is over 6 times better than RapidRider or MOXcatter. Moreover, our proposed SubScatter+ could increase the throughput of SubScatter by 30%.
KW - Backscatter communication
KW - IoT
KW - OFDM
UR - http://www.scopus.com/inward/record.url?scp=85215364577&partnerID=8YFLogxK
U2 - 10.1109/TMC.2025.3529265
DO - 10.1109/TMC.2025.3529265
M3 - Article
AN - SCOPUS:85215364577
SN - 1536-1233
JO - IEEE Transactions on Mobile Computing
JF - IEEE Transactions on Mobile Computing
ER -