Ground-based alternative to GPS achieves 10 cm accuracy – Physics World - physicsworld.com

Grounded: illustration of however SuperGPS would beryllium rolled retired successful a city. (Courtesy: TU Delft/Stephan Timmers)

Researchers successful the Netherlands person created a ground-based alternate to planetary outer navigation systems (GNSSs) – claiming that it could connection a acold greater positioning and timekeeping accuracy successful cluttered municipality environments. The team’s SuperGPS strategy uses an atomic-clock clip awesome that is distributed utilizing existing optical and microwave telecommunications technologies. The squad includes researchers from the Free University of Amsterdam, Delft University of Technology, and the institution VSL.

A GNSS specified arsenic GPS comprises a “constellation” of satellites that broadcast signals to devices connected the crushed specified arsenic mobile phones. The signals archer the instrumentality wherever the satellites are and however agelong the signals took to scope the device. The instrumentality uses this accusation to cipher its location. High accuracy is achieved by having an atomic timepiece onboard each satellite.

However, for a GNSS to enactment the instrumentality connected the crushed indispensable beryllium capable to person signals from astatine slightest 4 satellites, which tin beryllium hard erstwhile the idiosyncratic is indoors oregon surrounded by gangly buildings. Furthermore, awesome reflections from buildings tin degrade the accuracy of a GNSS. This is not lone a interest for navigation systems; GNSS timing signals are utilized to synchronize telecommunications networks and different systems.

Distributed signal

With these problems successful mind, Christian Tiberius and colleagues created SuperGPS arsenic a ground-based alternate to GNSS. Like a GNSS satellite, SuperGPS uses a clip awesome from an atomic clock. This awesome is distributed to basal stations utilizing fibre optics. The basal stations past broadcast the clip signals to idiosyncratic devices utilizing a high-bandwidth microwave signal. High bandwidth makes it imaginable for the strategy to weed-out signals that are reflected from buildings. Because microwave bandwidth is successful abbreviated supply, this is done utilizing respective idiosyncratic low-bandwidth signals to make a virtual precocious bandwidth that is astir 8 times wider than a GNSS signal. What is more, the signals utilized by SuperGPS are compatible with existing mobile telephone technology.

To trial their design, the squad installed six basal stations implicit an country of 660 m² connected the Delft campus. They recovered that their strategy could execute an accuracy connected the bid of 10 cm, which is amended than that achieved by GNSSs successful galore municipality environments.

The squad accidental that SuperGPS could payment a scope of applications including automated vehicles, quantum connection and next-generation mobile connection systems. The strategy could besides beryllium utilized arsenic a captious back-up to existing GNSSs and could signifier the ground of nationalist timing networks.

The probe is described successful Nature.