Integrity of the Trimble CenterPoint RTX Correction Service

In this contribution a new integrity monitoring system for the Trimble CenterPoint RTX Fast positioning service is introduced, that will allow RTX correction data to be used in safety-critical applications. The system monitors the integrity of the RTX correction data by computing carrier phase observation residuals for 20-25 independent monitoring station per RTX Fast service area, currently Europe and North America. Based on these residuals integrity checks are performed both on all newly generated corrections before broadcasting as well as on already broadcast corrections received by the monitoring stations. In case out-of-tolerance corrections are detected, the corrections are flagged as not usable. In addition when the outof-tolerance correction is detected with already broadcast correction data a corresponding alarm flag is sent to the user within seconds. In addition to describing the overall integrity concept and the new integrity monitoring modules, the accuracy of the RTX Fast corrections is assessed and examples of real-life integrity events are discussed.