An Improved Method for Strength and Carrier to Noise Ratio Controlling in Repeater GNSS Spoofing

Abstract Global Navigation Satellite System (GNSS) spoofing is an effective method for suppressing the unmanned air vehicle (UAV) threat. However, spoofing the unauthorized UAV is a complex task, it is necessary to maintain the signal strength and carrier to noise ratio (CNR) in the rational range. In this paper, an improved signal strength and CNR controlling method based on ranging radar and (APL) is presented. the range between the spoofing transmitter and UAV is measured by ranging radar, and the gain difference between the spoofing and authentic signal are considered by the APL, the spoofing signal strength and CNR are adaptive adjusted based on the measuring value of ranging radar and searching results of the APL. A numerical example is presented to demonstrate the efficiency of the method. Compared with the previous methods, the proposed method not only improves the signal strength stability, but also improves the CNR stability, and the effective range based on the method can cover all areas under arbitrary incident angle of spoofing signal.