Global navigation satellite systems (GNSS) are being the target of various jamming, spoofing, and meaconing attacks. This paper proposes a new statistical test for the presence of multiple spoofers based on range measurements observed by a plurality of receivers located on a rigid body platform. The relative positions of the receivers are known, but the location and orientation of the platform are unknown. The test is based on the generalized likelihood ratio test (GLRT) paradigm and essentially performs a consistency check between the set of observed range measurements and known information about the satellite topology and the geometry of the receiver constellation. Optimal spoofing locations and optimal artificial time delays (as induced by the spoofers) are also determined.Exact evaluation of the GLRT requires the maximum-likelihood estimates of all parameters, which proves difficult. Instead, approximations based on iterative algorithms and the squared-range least squares algorithm are derived. The accuracy of these approximations is benchmarked against Cramér-Rao lower bounds.Numerical examples demonstrate the effectiveness of the proposed algorithm and show that increasing the number of GNSS receivers makes the attack easier to detect. We also show that using multiple GNSS receivers limits the availability of optimal attack positions.

全球导航卫星系统（GNSS）已成为各种干扰，欺骗和暗中攻击的目标。本文基于位于刚体平台上的多个接收器所观测到的距离测量结果，提出了一种新的统计测试，用于检测多个踏板的存在。接收器的相对位置是已知的，但是平台的位置和方向是未知的。该测试基于广义似然比测试（GLRT）范例，并且实质上在观察到的距离测量值的集合与有关卫星拓扑和接收机星座几何的已知信息之间执行一致性检查。还确定了最佳欺骗位置和最佳人工时延（由欺骗者诱发）。GLRT的精确评估需要所有参数的最大似然估计，这被证明是困难的。取而代之的是，得出基于迭代算法和平方范围最小二乘算法的近似值。这些近似值的准确性以Cramér-Rao下界为基准。数值示例证明了该算法的有效性，并表明增加GNSS接收器的数量使攻击更易于检测。我们还表明，使用多个GNSS接收器会限制最佳攻击位置的可用性。数值算例表明了该算法的有效性，并表明增加GNSS接收器的数量使攻击更易于检测。我们还表明，使用多个GNSS接收器会限制最佳攻击位置的可用性。数值算例表明了该算法的有效性，并表明增加GNSS接收器的数量使攻击更易于检测。我们还表明，使用多个GNSS接收器会限制最佳攻击位置的可用性。