Detection of deception signal used to deceive geolocation receiver of a satellite navigation system

1. A method of detecting a deception signal associated with a satellite navigation system, comprising:

receiving the deception signal with a receiver normally used for the satellite navigation system;

calculating at least type of observable data from data provided by the deception signal and data provided by the receiver;

wherein the observable is at least one type of observable data from the group of: time offsets, pseudorange residuals, Doppler residuals, and velocity of the receiver calculated from the deception signal;

storing a consecutive series of observable values; and

monitoring the stored observable values to determine if there is an abrupt change in the observable values.

2. The method of claim 1 , wherein the satellite navigation system is a GPS system.

3. A method of detecting a deception signal associated with a satellite navigation system, comprising:

receiving the deception signal with a receiver normally used for the satellite navigation system;

calculating time offsets between the time provided by the deception signal and the local time of the receiver;

storing a consecutive series of time offset values; and

monitoring the stored offset values to determine if there is an abrupt change in the offset values.

4. The method of claim 3 , wherein the satellite navigation system is a GPS system.

5. The method of claim 3 , further comprising the step of determining whether the change is in the direction of additional time delay.

6. A method of detecting a deception signal associated with a satellite navigation system, comprising:

receiving the deception signal with a receiver normally used for the satellite navigation system;

calculating the pseudorange residuals;

storing a consecutive series of pseudorange residual values; and

monitoring the stored pseudorange residual values to determine if there is an abrupt change in the values.

7. The method of claim 6 , wherein the satellite navigation system is a GPS system.

8. The method of claim 6 , further comprising the step of determining whether the change exceeds a predetermined threshold value.

9. A method of detecting a deception signal associated with a satellite navigation system, using a mobile receiver, comprising:

receiving the deception signal with a receiver normally used for the satellite navigation system;

determining the velocity of the receiver;

calculating the Doppler residuals associated with the deception signal and the receiver;

storing a consecutive series of Doppler residual values; and

monitoring the Doppler residual values to determine if there is an abrupt change in the values.

10. The method of claim 9 , wherein the satellite navigation system is a GPS system.

11. The method of claim 9 , further comprising the step of determining whether the change exceeds a predetermined threshold value.

12. A method of detecting a deception signal associated with a satellite navigation system, using a mobile receiver, comprising:

receiving the deception signal with a receiver normally used for the satellite navigation system;

calculating a velocity of the receiver from a previous location and a current location as determined from the deception signal;

storing a series of velocity values; and

monitoring the velocity values to determine if there is an abrupt change in the values.

13. The method of claim 12 , wherein the satellite navigation system is a GPS system.

14. The method of claim 12 , further comprising the step of determining whether the change exceeds a predetermined threshold value.

15. A detector for detecting a deception signal associated with a satellite navigation system, comprising:

a processor programmed to receive data in the deception signal from a receiver normally used for the satellite navigation system;

to calculate at least type of observable data from data provided by the deception signal and data provided by the receiver;

wherein the observable is at least one type of observable data from the group of: time offsets, pseudorange residuals, Doppler residuals, and velocity of the receiver calculated from the deception signal;

memory for storing a consecutive series of observable values; and

wherein the processor is further programmed to monitor the stored observable values to determine if there is an abrupt change in the observable values.