NSL: Monitoring the Performance of GNSS

GNSS Integrity and Signal Monitoring Observatory (GISMO)

GISMO has been developed to meet the needs of organisations that provide GNSS-based products and services reliant on a minimum level of performance from GNSS.

GISMO provides a full analysis of GNSS positioning and timing for any particular application, providing metrics on a 24/7 basis. This software suite can operate with any GNSS network which provides dual frequency code and carrier data.

By combining monitoring with prediction, GISMO can also identify scheduled black-spots in GNSS accuracy and integrity, which can affect service availability, as well as unscheduled events which affect continuity of service.

GISMO produces graphical and descriptive results, which can either be displayed online, or used to generate periodic reports. The system is capable of the following distinct monitoring services.

Satellite availability, accuracy and integrity
Signal reception and signal quality statistics
Identification of faults and failures
Record of published NANUs
Comparison of NANU information and monitored GPS constellation behaviour
Satellite range error analyses
Station error analyses and modeling
Predicted satellite availability, accuracy and integrity
Comparison between predicted and observed values
Ensuring GPS is meeting the criteria specified within "Global Positioning System Standard Positioning Service (GPS SPS) Performance Standard - 2008"
Ensuring GPS is meeting the criteria specified within "ICAO SARPS (2006), Annex 10: International Standards and Recommended Practices"

Example GPS Errors

GISMO can monitor the performance of GPS recorded at any tracking network worldwide. The animation demonstrates the deterioration of GPS for a period covering a few hours observed at a number of reference stations distributed globally.

Although GPS is typically performing at the sub-5m level, errors of several km can occur.

Web Design Company: QuantumCloud