US Patent 11385356 System for detecting signal spoofing by monitoring for abnormal divergence in pseudorange values

A spoofing detection system including at least one antenna, a receiver and a controller is provided. The at least one receiver is in communication with the at least one antenna to receive detected satellite signals. The controller is configured to determine raw pseudorange values from the received satellite signals. The controller is further configured to apply at least one first filter on the raw pseudorange values to generate at least an output of first filtered pseudorange values. The controller is also conjured to compare an output of the first filtered pseudorange values with one of the raw pseudorange values and second filtered pseudorange values from a second filter. The controller is further configured to determine if spoofing is present in the received satellite signals based on a determined divergence between the output of first filtered pseudorange values and one of the raw pseudorange values and the second filtered pseudorange values.