Navigation Positioning and Tracking
To achieve the best performance of any positioning system, it is essential to consider all aspects of the system from the reference stations to the system users and the transmission of data between them. Through the development of operational systems, we have studied defined and evaluated algorithms for all areas of GNSS and dGNSS positioning systems.
At the reference station end, we have developed tools to allow multipath site surveys to be performed. In addition, we have defined all of the algorithms required for conventional or network differential GNSS.
For any augmentation system, it is necessary to transmit correction data to the system users. We have considerable experience with designing transmission schemes for this data channel using state-of-the-art techniques for data coding, compression and encryption.
For ultimate positioning performance, it is essential to minimise all error components. We have studied, defined and implemented schemes to counteract the effects of the ionosphere and troposphere.
At the user end, we have defined positioning algorithms for a wide range of systems, encompassing GNSS, dGNSS and integrated systems. Depending upon the application, we are able to select the best-suited approach, whether filtered or unfiltered, to fit the requirements of the target user. We have developed algorithms for RTK positioning that have been demonstrated operationally with dual-frequency GPS, and through the development of the Galileo Constellation Simulator, have also been demonstrated with multi-frequency Galileo.