Influence of the time-delay of correction for BDS and GPS combined real-time differential positioning

Real-time differential (RTD) positioning can achieve a real-time metre-lever positioning based on the differential correction data from a nearby reference station. However, the time-delay of correction data is generally unavoidable when receiving it from the reference station in real-time. Multi-global navigation satellite system combined positioning has the advantages of improving the positioning availability, continuity and accuracy; however, it remains unknown whether it can effectively overcome the time-delay of differential correction in RTD positioning. This Letter focus on the tolerance of time-delay for differential correction in BeiDou global navigation satellite system (BDS) and global positioning system (GPS) combined RTD positioning. Based on a set of static data and a set of dynamic data, the performances of BDS standalone, GPS standalone and BDS and GPS combined RTD positioning by 15 kinds of time-delay of the differential correction data were studied and compared. The numerical results show that, BDS and GPS combined RTD positioning can tolerate longer time-delay of the corrections than BDS or GPS standalone positioning for the same requested positioning accuracy.