Effect of Frequency Domain Anti-Jamming Filter on Satellite Navigation Signal Tracking Performance

Abstract

Among the satellite navigation anti-jamming techniques, frequency domain anti-jamming (FDAJ) filter is a simple-realized method to suppress multi-tone continuous wave, sweep continuous wave and narrowband interference quickly and efficiently, without convergence problems, so it has been widely utilized to the GNSS receivers in practice. FDAJ filter will distort useful navigation signal while suppressing interference, when it is inserted into a receiver. The effect of the FDAJ filter on the observation quality of navigation signal is worth attention, especially now that more and more high-precision receivers use anti-jamming filter. In this paper, the FDAJ filter is modeled as a band rejection filter ideally firstly. Then the impact of FDAJ filter on pseudo-code tracking accuracy and the output signal-to-noise ratio (SNR) is derived, based on the mathematical models of the receiver tracking loop phase detector and loop filter. At the end, according to the mathematical simulation and analysis, it is showed that the FDAJ filter will not cause tracking error bias for pseudo-code phase, but a decline of tracking accuracy and output SNR.