Vector tracking technology is one of the key technologies of satellite navigation. As the threat of spoofing interference to satellite navigation security is increasing enormously, the influence of spoofing interference on vector receivers must be better understood to improve the anti-spoofing capability of vector tracking technology. This paper focuses on the influence of spoofing interference on three typical vector tracking loops. This study derives the mean tracking error caused by spoofing interference and the loss of lock conditions in the tracking loops. The analysis results were verified using a signal source simulator and a software receiver. The results show that spoofing interference can lead to non-zero mean tracking errors, reduce loop tracking accuracy, and even cause loop lock loses. Vector receivers can use this feature to improve anti-spoofing abilities.

Intermediate spoofing can impact most off-the-shelf Global Navigation Satellite Systems (GNSS) receivers, therefore low cost detection of such spoofing is very important to protect the reliability of the GNSS receivers used in critical safety and financial applications. This paper presents two strategies to analyze attacks by intermediate spoofing attackers to identify the weaknesses of such attacks. The analyses lead to a code and carrier phase consistency detection method with simulation results showing that this method can indicate the receiver when spoofing has occurred. The method can be used by most receivers, is inexpensive, and requires only a small software upgrade.