Fast Interference Detection Aided Notch Filter and Switched Tracking Loop for Mitigating Pulsed CWI in GNSS Receiver

摘要

The GNSS signals are vulnerable to radio frequency interferences. Among these interferences, continuous wave interferences (CWIs) are able to jam the GNSS signals. After pulse-modulation, the CWIs further cause the useful signal losses. To smooth the effects of useful signal losses, a notch filter with detection algorithm based on power switching tracking loop is proposed. The algorithm uses a time domain detector in order to reduce the computation cost. What's more, the periodically switches of the notch filter and the tracking loop are able to smooth the fluctuations of the Doppler frequencies and positioning estimation. A series of tests show that the method mitigates the effects of pulsed CWIs and improves the anti-jamming capability of the receiver.