Gnss signal authenticity verification using carrier phase measurements with multiple receivers

Abstract

Structural interference signals can severely jeopardize the performance of GNSS receivers which may lead to serious consequences for scores of applications. This type of interference is designed to be very similar to the authentic GNSS signals; therefore, it is very difficult for a conventional receiver to discriminate them from genuine observations. This research focuses on the application of a carrier phase capable dual antenna receiver (or two spatially separated receivers) to allow authenticity verification and reliable measurements classification. Assuming that all counterfeit PRNs originate from the same source, the proposed method identifies fake measurements based on their time invariant carrier phase double differences. The proposed detection procedure is based on a combination of GLRT and graph theory formulated to classify counterfeit and authentic signals and to reduce the authenticity verification time. Simulations and real-data processing results verify that the proposed technique can successfully classify the authentic and counterfeit measurements within a few minutes. The real-world performance of this method has also been verified on carrier phase capable GNSS receivers. The theoretical analyses and processing results show that the performance of this technique improves as the observation interval or receiver antenna spacing increases.