We recently completed a project in partnership with Frontier SI to test new Satellite Based Augmentation Systems (SBAS) GNSS receivers. SBAS technology allows the error in a GNSS position to be corrected in real time based on a correction signal received directly from the satellites. Consequently, there is not need for a base station, real time link, or post processing.

Test site for SBAS receivers in Northern Tasmania
Our aim was to test how well the SBAS receivers would work when attached to a UAS and if more accurate positions could be used to improve the accuracy of orthophotos generated via direct georeferencing. Tests were performed in an agricultural context, using a multi spectral camera where timely and accurate data are necessary to track crop health.

False colour orthoimage derived from SBAS receiver test
We found that the SBAS systems worked and could provide more accurate GNSS data in real time compared to the standard navigation grade data recorded on the UAS, but suffered from a long convergence time and were not as accurate as traditional Real Time Kinematic (RTK) solutions. Further development of the SBAS enabled GNSS receivers is ongoing to address these issues.
The results from the project are part of the SBAS economic benefits report.