Exploiting GNSS Array Processing to exclude Non-Line-Of-Sight Signals in a Real-Time Vector Tracking Algorithm

Kurzfassung

This paper describes the architecture of a vector-tracking algorithm, using a real-time Global Navigation Satellite System (GNSS) array-antenna receiver, which is based on an Error-Position-State formulation as proposed in (Lashley, 2009). The tracking algorithm is tested and validated in real-time scenarios, which includes a simulative GNSS environment in the laboratory, as well as outdoor testing, whereby the functionality of the system can be determined. In order to improve the robustness of the receiver an exploitation of the Direction of Arrival (DoA) measurements is implemented, which allows the exclusion of unauthentic or unwanted signals in the Kalman Filter updating process. An error vector based on comparison and statistically testing of the measured DoAs against the expected DoAs (Meurer et al., 2016), which can be obtained by geometric calculation of the receivers position and attitude, is generated and contains information about the credibility of each tracking channel. Manipulating the measurement covariance matrix of the central navigation Kalman filter with this error vector will decrease the contribution of incredible channels not only to the Position/Velocity/Timing (PVT) solution, but also to the tracking loops, because of the vector tracking feedback.