What is the main difference / benefit of BDS vs. other GNSS? I have read somewhere that BDS can track and provide feedback on users. Do you have any information about this? And if so, do other GNSSs have this capability? Thanks
Beidou has no particular advantage over other GNSS apart from possibly the relatively large number of GEO's and IGEO's positioned suitably for Chinese use (increased availability). Having more GNSS available (such as Beidou and Galileo) is good for users due to the increased availability in challenging environments such as urban canyons. Typically a receiver needs to track 4 signals from a given constellation in order to report a PVT solution, which in high obscuration environments could be impossible. However a multi-GNSS receiver could report a position by tracking 4 satellites (again) but they could all be from different constellations (or any combination such as 2 GPS, 1 GLONASS and 1 Beidou) thus high obscuration environments are less challenging due to increased availability. All GNSS systems are unaware of the positions of their users. Of course once a user's position is known another system can easily transmit this information for tracking purposes.