GNSS intermediate spoofing detection via dual‐peak in frequency domain and relative velocity residuals

GNSS intermediate spoofing is a big threat to GNSS‐dependent services because of its strong concealment. When the carrier Doppler of the spoofing signal is not locked to that of the authentic signal, such spoofing will result in the presence of dual‐peak in the signal spectrum. In the absence of interference, there should be no dual‐peak. In the multipath scenario, dual‐peak may exist, but the number of dual‐peaks and relative velocity residual magnitudes of dual‐peak signals are different from those in the spoofing scenario. Therefore, an intermediate spoofing detection technique based on dual‐peak in frequency domain and relative velocity residuals is proposed in this study, which can not only detect spoofing but also distinguish spoofing scenario from the multipath scenario. Fast Fourier transform based methods are used to detect the dual‐peak and extract the Doppler difference of the dual‐peak, and the relative velocity residual calculation based on Doppler differences is derived. The performance of this approach is evaluated both analytically and experimentally: simulation results show spoofing false alarm probability in the multipath scenario is small, which indicates that spoofing scenario and multipath scenario can be well distinguished; and the effectiveness is verified based on the Texas Spoofing Test Battery (TEXBAT).