Image: Lockheed
What’s New: More recognition that a systems approach to PNT is needed.
Why It’s Important: GPS is vulnerable, and no one thing can take its place as a low SWAP-C capability.
What Else to Know:
- This is not a new idea. DOD published a PNT Strategy in 2018 that called for a multi-layered approach.
- There are way more civilian users than military. Civilians need multiple backups as well.
- US DOT in a January 2021 report that the nation needs multiple methods to source PNT and, based on the demo they completed, those include signals from space, terrestrial broadcast, and fiber.
‘No silver bullet:’ Military will need multiple systems to back up GPS
Each technique available now or in the foreseeable future for what is known as alt-PNT comes with a need to make size, weight, power and cost trade-offs based on what type of platform is being used, according to experts.
WASHINGTON — As Defense Department concern grows about the increasing ability of adversaries to disrupt GPS satellite signals, experts warn that there is no one-size-fits-all alternative to meet military needs for positioning, navigation and timing (PNT) capabilities.
Radio-frequency (RF) signals broadcasted from Global Positioning System satellites can be used by a wide variety of platforms for almost an infinite number of military missions — ranging from helping a soldier navigate an all-terrain vehicle in an unfamiliar landscape to steering an airborne missile to its target.
The problem, as is being demonstrated every day in conflict zones such as Ukraine and Gaza, is that GPS RF signals are weak and easily jammed — or, perhaps worse, spoofed to fool users into going to or looking at the wrong place. For example, in March a plane carrying UK Defence Minister Grant Shapps from Poland back to Britain lost GPS near Kaliningrad due to suspected Russian jamming — something that his spokesperson said is not unusual over Russia’s Baltic coast.
