Experimental validation of GNSS repeater detection based on antenna arrays for maritime applications

In this work, we present an antenna array-based algorithm to detect GNSS repeater and/or spoofing attacks with an experimental validation. With an array receiver capable of measuring the impinging ranging signals direction of arrival in terms of azimuth and elevation, it is possible to estimate the antenna platforms attitude. The fact that this information is computed (w.r.t. a reference frame) during the position calculation is used. We propose an algorithm aiming to find the relation between both representations. This mapping defines the receiver’s attitude in terms of pitch, roll and yaw angle. The residual of this mapping is used to construct a quality metric for the mapping. If a threshold is undershot, spoofing/repeating is indicated. The performance is demonstrated using software simulations. To show the capabilities under realistic conditions, a test platform is described. It consists of a real-time array receiver and a sampling device enabling post-processing. A maritime measurement campaign including two vessels—one acting as receiver and the other acting as transmitter—is portrayed. Finally, the real-time and post-processing performance of the algorithm is evaluated.