%0 Journal Article %A Jian Wen %A Hong Li, %A Mingquan Lu %T A Flexible GNSS Spoofer Localization System: Spoofing Discrimination and Localization Method %D 2022 %R 10.33012/navi.511 %J NAVIGATION: Journal of the Institute of Navigation %P navi.511 %V 69 %N 1 %X Global navigation satellite systems (GNSS) are vulnerable to spoofing attacks. To shut down a spoofer, it is necessary to locate the spoofer first. Many spoofer localization systems use long cables for the synchronization of multiple receivers. However, a flexible spoofer localization system free from cables is sometimes essential so the receivers can move freely and are flexible to deploy. This paper solves two major problems in developing such a system: spoofing discrimination without requiring synchronization and having an effective method using asynchronous raw measurements with no other assistance. First, this paper proposes to use the extended pseudorange double-difference method to discriminate spoofing signals. The performance is then analyzed and the effectiveness is verified. Then, a quasi-synchronization spoofer localization method (QSSL) is proposed, and it is verified that its localization performance can attain the Cramer-Rao lower bound. Above all, a field experiment demonstrates the effectiveness of the proposed methods and the feasibility of such system. %U https://navi.ion.org/content/navi/69/1/navi.511.full.pdf