The main function of GP-Cloud is to detect the anomaly in the GNSS signals and classify them. GP-Cloud supports anomaly/interference/event classification into the following classes:


Spoofing


This alarm is raised when the system detects a signature of false GNSS signals in data coming from GP-Probe TGE2. 

Interference with certain types of modulation and signal structure can cause significant degradation in the positioning/time accuracy of GNSS receivers. Such interference may be classified as spoofing. Our general approach is as follows:

  • If the interference reduces the reception quality of GNSS signals, it is jamming. 
  • If the interference causes significant errors in pseudorange, Doppler, etc, it can be classified as spoofing. As it may cause a GNSS receiver to output incorrect coordinates and time.



Jamming

Interference causes a decrease in SNR and the number of visible satellites. GNSS receiver either fails to produce a navigation solution at all or produces it with minor errors.



Interference

Interference is detected by analyzing the RF spectrum and power in the GNSS bands. But it does not affect the reception quality of GNSS signals.



Anomaly

The system detects abnormal behavior of GNSS signals that are not typical for a particular data source. Classification of anomalies is not possible due to insufficient data



Low Position Accuracy

This status is displayed when the accuracy of coordinates generated by a receiver surpasses the defined limits. Coordinate accuracy is calculated as the difference between the GNSS receiver coordinates and a reference position set in GP-Cloud.




PPS Offset

Certain modifications of the GP-Probe come with a built-in module for measuring PPS phase errors. By connecting the PPS output of your time server to the PPS input of the GP-Probe, you can continuously monitor the accuracy of your time synchronization system. In GP-Cloud, you can define PPS accuracy limits. If these boundaries are surpassed, a "PPS Offset" event will be detected and you will receive a notification in real-time.



Hardware Error

All GPSPATRON equipment is designed with an automatic hardware error detection system.
If a problem occurs, GP-Cloud displays the "Hardware Error" status with the error code and description of the reason behind the error.



Offline

Detected when the data source is disconnected for more than 10 seconds.