GNSS spoofing localization based on differential code phase

Spoofing is a great threat to GNSS (Global Navigation Satellite System) based applications. Many effective spoofing detection methods have been proposed, while few effort is paid to spoofing localization, which is of equally importance. GNSS interference localization is mainly based on TDOA (Time Difference of Arrival) estimations and one widely adopted method to measure the TDOA is based on signal cross-correlation. This paper proposes a differential code phase (DCP) based technique to estimate the spoofing TDOA. The TDOA is estimated as the ratio between DCP and spoofing code frequency. The DCP based TDOA model and its estimation error model are mathematically formulated. Also, the performance comparison between the DCP based and the widely used cross-correlation based TDOA techniques is conducted based on simulation results. Results show the DCP based method can be more accurate in TDOA estimation.