Year: 2023
Type: conference-paper
Abstract: Long-range backscatter localization is a promising technology for the Internet of Things. Existing works cannot work well for distributed base stations and low-cost tags. We present LocRa, which provides accurate localization for long-range backscatter with distributed base stations. We present a novel method to extract accurate channel information and synchronize the phase of different base stations. To compensate for the frequency and phase error on low-cost tags, we combine multiple channel measurements and eliminate the error by aligning different channels. Finally, we exploit frequency domain characteristics of the backscatter signal to extend its bandwidth and improve the SNR, thereby enhancing the localization accuracy. We prototype LocRa tags using custom low-cost hardware and implement LocRa base stations on USRP. Through extensive experiments, we show that the localization error of LocRa is 6.8 cm and 88 cm when the tag is 5m and 50m away from the base station, which is 3.1× and 2.3× better than the state-of-the-arts methods.
Institution: Tsinghua University
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Awards: G6293625599, G6776778946, G8431760780
OpenAlex ID: W4380926540