Implications of a “system of Systems” Receiver

The US Global Positioning System (GPS) and the USSR (and later Russian) system Glonass have existed for decades. Europe is developing Galileo and China launched Beidou which was the first Regional Navigation Satellite System (RNSS) and then announced Compass, a Global Navigation Satellite System (GNSS). Japan is planning its own regional augmentation to GPS and Galileo known as the Quasi-Zenith Satellite System (QZSS). India has proposed the Indian RNSS (IRNSS). Most of the big space players all now have, or will launch, a Navigation Satellite System (or NSS – which includes both GNSS and RNSS). One of the advantages that new systems bring is that they provide simply “more satellites”. Various GNSS user groups can demonstrate that the more satellites and signals they have, the better. Indeed, the advantage that the “extra” Glonass satellites provided for RTK-GPS saw Topcon gain market share in the late 1990s. Now many manufacturers offer a GPS/Glonass product, and even offer GPS/Glonass/Galileo receivers (GPS World, 2009). So nominally, this rapid increase in satellite systems and constellations over the next 5 years means that ever more satellites and signals will be available, and a receiver that can exploit all of the new signals may be the “ultimate” in satellite positioning and navigation. The concept of the “System of Systems” (SoS), using as many systems as possible, is a relatively new one and deserves some examination. This paper looks at the new systems and tries to gauge if there is a genuine advantage in a SoS receiver, and how high-end users may benefit. THE NAVIGATION SATELLITE SYSTEMS Global Navigation Satellite Systems (GNSS)