Global navigation satellite system (GNSS) signals are vulnerable to radio frequency interference (RFI) and spoofing. RFI detection has become trivial with many detection algorithms available and built into GNSS receivers; this is not the case with spoofing. GNSS spoofing can involve generating false GNSS signals with one or more altered components of GNSS satellite transmissions: radio frequency (RF) carrier, pseudorandom noise codes, and/or the broadcast navigation messages. We present GNSS interferometric reflectometry (GNSS‐IR) signature‐based defense: a new methodology to defend wireless space‐based positioning, navigation, and timing (PNT) transmissions against spoofing by leveraging existing, fixed GNSS receivers used in GNSS‐dependent critical infrastructure and key resource sectors. GNSS‐IR signature‐enabled defense provides spoofing and RFI detection without any changes to existing architecture by conducting input validation of GNSS receiver observables against the generated GNSS‐IR truth calibration signatures. This paper includes an overview of the theory, methodology, and results of live‐sky signature variability experiments.

中文翻译：

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GNSS干涉反射法基于签名的防御

全球导航卫星系统（GNSS）信号容易受到射频干扰（RFI）和欺骗的影响。RFI检测变得无足轻重，GNSS接收器内置了许多可用的检测算法。欺骗并非如此。GNSS欺骗可能涉及生成带有GNSS卫星传输的一个或多个更改部分的虚假GNSS信号：射频（RF）载波，伪随机噪声代码和/或广播导航消息。我们介绍了基于GNSS干涉反射法（GNSS‐IR）签名的防御：一种新方法，可利用依赖于GNSS的关键基础设施中现有的，固定的GNSS接收器来防御欺骗的无线空基定位，导航和定时（PNT）传输和关键资源部门。通过针对生成的GNSS-IR真值校准签名对GNSS接收器观测值进行输入验证，启用GNSS-IR签名的防御功能可以在不对现有体系结构进行任何更改的情况下提供欺骗和RFI检测。本文概述了实时天空签名变异性实验的理论，方法和结果。