High-accuracy augmented positioning services will become the new normal

Guy Buesnel PNT Security Technologist, Spirent

The need for better positioning authentication and proof of location.

There is a growing focus on the integrity of GNSS data. New message authentication schemes like the Galileo Open Service Navigation Message Authentication (OSNMA) and the CHIMERA authentication scheme being developed for GPS will allow user equipment to differentiate between authentic and fake Galileo and GPS signals.

In their efforts to reduce carbon footprint and verify the provenance of goods (identifying illegal fishing, for instance), the supply chain sector will be looking to authentication technologies like these to provide reliable proof of position – as well as to enable more efficient trajectories.

High-accuracy augmented positioning services will become the new normal

In 2022, we will see new efforts from chipset providers and OEMs to offer highaccuracy augmented positioning services to enable centimetric accuracy. This will also help to improve the reliability of PNT signals for a variety of applications, including surveying, mapping, precision agriculture, asset management, UAV, construction, robotics, and more— applications that traditional GNSS is just not accurate enough to support.

Week number rollover fallout will continue

We will continue to come across Week Number Rollover incidents and reports in 2022. Whilst the event was known about and oh-so predictable – on 6th April 2019 the GPS satellite system reached the end of its second epoch, with the 10-bit week number encoded in its data stream resetting from 1,024 to zero, and a number of systems encountered problems on the date of the rollover. And there are more to come.

This is because some manufacturers have squeezed more lifespan into their receivers by using pivot dates to start counting the 1,024 weeks from the date the firmware was compiled, rather than from the first day of the second GPS epoch – meaning that more Week Number Rollover issues will come to light during this coming year. It’s very simple to test for Week Number Rollover issues using a GNSS simulator, helping to prevent any undesired behaviour in time-dependent systems.