The Racelogic DGNSS RTK Base Station is designed to improve positional accuracy of VBOX's and other compatible GNSS systems by calculating and transmitting differential correction data. By setting up the Base Station in a known position, it is able to accurately monitor the difference between its known position and the position that it is calculating from GNSS satellite signals.
The difference is then transmitted via radio to allow a remote GNSS system to correct its position. The differential correction message can be broadcasted in RTCM v2, RTCM v3, RTCM v3.2 MSM4 and MSM7, or proprietary RTK formats using an internal or mast mounted radio modem transmitter. Depending on the type of base station and roving unit used, position accuracies of up to 2 cm (95 % CEP) are available.
The 95 % CEP value refers to the Circular Error Probable. For example, in the case of the RTK enabled base station in conjunction with an RTK enabled VBOX III, VBOX 3iS or VBOX 3i, the GPS position calculated will be within a 2 cm radius of the true position 95 % of the time.
The image below shows the results of static positional data from VBOX systems with and without local DGPS corrections.
- The red plot shows position scatter from a non-corrected VBOX.
- The blue plot shows position scatter from an SBAS corrected VBOX.
- The green plot shows position scatter from an RTCM (40 cm) corrected VBOX.
- The purple plot shows position scatter from a 20 cm corrected VBOX 2 series product.
- The yellow plot shows position scatter from an RTK (2 cm) corrected VBOX 3 series product.