An efficient algorithm for determining the correspondence between DFREI and σ_DFRE for a dual-frequency multi-constellation satellite-based augmentation system

Global navigation satellite systems (GNSSs) will broadcast two open signals for civil aviation within the next ten years. Satellite-based augmentation system (SBAS) providers are currently developing the dual-frequency multi-constellation (DFMC) SBAS interface control document (ICD) to take advantage of the four GNSSs and two signals. In order to ensure the interoperability, a SBAS provider is allowed to determine the correspondence between DFREI and σ_DFRE based on the performance of its service within the frame of the ICD. Considering that the search space of the correspondence determination is too larger, an algorithm is proposed, which reduces the search space by decorrelating DFREIs. The evaluation based on real data shows that the effect of quantitation error resulted from the correspondence determined by the algorithm to SBAS service performance is neglectable, indicating that the algorithm is efficient. The algorithm could be of value for SBAS providers to design the correspondence.