Adaptive Antenna Array Coupling for Anti-Jamming GNSS Real-Time Kinematic Applications

A system of two Antenna Arrays (AA) designed to receive the Global Navigation Satellite Systems signals is described in this paper. The received signals are utilized for highprecision correlation interferometry direction finding based on the Real-Time Kinematic (RTK) approach. Since the groundbased receivers usually operate in the presence of natural or intentional interferences, the AAs have to be Adaptive (AAA) so that they implement spatial filtering of the interfering signals. This paper presents the architecture of the considered RTK system with the AAAs, the Linearly Constrained Recursive Least Squares algorithm of the AAA weights calculation and an accurate phase estimation method for the AAA output signals. The computer simulation of two rectangular 3-by-3 AAAs demonstrates that such a system is able to suppress up to 8 interferences in the case when the Signal-to-Interference Ratio is equal to -90 dB. The proposed phase unwrapping and averaging procedure ensures more accurate phase differences estimation compared to the standard unwrap methods. The obtained accurate phase differences enable a reliable interferenceprotected direction finding via the proposed system.