Prime position: Industry explores alternative PNT solutions

The Collins Aerospace NavHub-100 (part of its MAPS Gen II solution) installed in a vehicle. (Collins Aerospace)

The benefits of global navigation satellite systems (GNSS) are ubiquitous. They provide the positional information for navigation systems in modern military command-and-control (C2) systems and for civilian cars and smartphones, as well as highly accurate timing crucial to banking, transport, stock markets, utilities, and military operations.

The overall output of GNSS is known as position, navigation, and timing (PNT). Having reliable, trusted, and assured PNT (APNT) is fundamental to the successful execution of nearly every aspect of modern military operations, from a section commander knowing team members are on the battlefield to guiding the most sophisticated weapon systems and controlling autonomous platforms.

There are four major GNSS: the 31-satellite GPS constellation, which is being upgraded with a third-generation space segment; the 24-satellite Russian GLONASS, which was refurbished in 2012; the 24-satellite European Union Galileo system; and the Chinese BeiDou system. The Japanese Quasi-Zenith Satellite System (QZSS) and Indian Navigation with Indian Constellation (NavIC) regional systems can be added to these.

However, the vulnerability of GNSS has become increasingly apparent. Apart from kinetic attack and accidental collision with space debris, the systems are open to electronic attack. The signal is very weak, with the transmitters being described as having the wattage of a refrigerator light bulb. It is therefore vulnerable to jamming, interference, and spoofing – the attempted deception of the receiver by broadcasting incorrect signals that will alter the positional or the timing information or both.

Instances of jamming or spoofing, such as during major NATO exercises and in Ukraine before major hostilities erupted, are well documented. There have even been instances of inadvertent interference with GPS, notably in the US.