Alternative Navigation Systems to GPS

Graphic: NOAA

Last week, a Russian government official announced on state television that Russian ASAT capabilities could wipe out 32 NATO GPS satellites. That’d leave users around the world without access to navigation services…and US weapons systems without a compass. 

Sitting ducks? As of Nov. 11, there were 26 operational GPS satellites out of 31 total in orbit. That number has been as high as 32, hence the Kremlin’s threat. The satellites supply both civil and government navigation data. 

  • Russia’s recent ASAT strike kaboomed one of their own defunct satellites ~480km above Earth. GPS is far higher, at ~20,200km. 

The US-run GPS system isn’t the only version of a satellite navigation, or satnav, system: Russia has GLONASS, China has BeiDou, and the ESA launched two additions to their Galileo satnav constellation earlier this week. Regional satnav systems build on GPS by boosting accuracy in more targeted areas of the world. 

  • GPS is the most-used system globally, with ~4B users as of 2019, per the US Air Force.
  • Galileo has ~2.3B users globally, ESA reports.

Alternatives to GPS…and don’t say maps: Luckily, GPS is not the only mechanism we have for navigation. The Pentagon is developing other Positioning, Navigation, and Timing (PNT) systems, mulling contingency plans should something go awry with GPS. Magnetic navigation, inertial sensing, and navigation by the stars are all on the table.

And the DoD isn’t the only entity developing alternative PNT systems. Academic researchers are exploring new satnav possibilities, too. In November, UC Irvine researchers published evidence that they had used signals indicating the location and movement of Starlink satellites to pinpoint a location on Earth (building on similar research published by UT Austin professors). 

  • The Irvine researchers’ method gave a location within ~8 meters. GPS is accurate from an upper bound of ~5 to as little as 0.3 meters.
  • Zak Kassas, lead author of the study, said that this form of navigation will increase in accuracy as SpaceX rounds out its constellation.

Others to watch: South Korea plans to spend $3.1B to develop a Korea Positioning System made up of eight satellites. And Xona Space Systems recently raised $8M to fly a demonstration mission of its PNT payload. The California startup intends to build an alternative to GPS in LEO. 

Payload’s takeaway: The ‘push’ to develop GPS alternatives stems from threats to the legacy system and operational risks. But there’s also a ‘pull’ for more accurate navigation systems. Mission-critical, hyper-accurate positioning data could benefit all manner of fleet operators, from launch vehicles to self-driving cars to drones.

Related Stories

How the ISS National Lab Went Commercial

The US’ highest scientific laboratory is changing with the times.


The Space Industry’s Climate Impact: Part 1

Space technology benefits humanity every day, from scientific understanding to the nuts and bolts of supporting the systems that enable life as we know it, but some advocates worry regulators are not paying enough attention to the potential downsides of a bustling space economy.  


Exclusive: Euroconsult Values 2022 Space Economy at $464B

In its flagship Space Economy Report published this morning, Paris-based Euroconsult finds that the space market grew 8% in 2022. This report is the gold standard for market intelligence on the end-to-end space economy, from upstream manufacturers to downstream service providers and end users across civil, military, and commercial space.  The space value chain… …as […]


Space Markets: The Year in Review

The key theme for aerospace within financial markets has been the bifurcation of performance between the traditional aerospace and defense (A&D) sector and space SPACs.  Despite the broader market’s abysmal performance this year, traditional A&D companies have outperformed phenomenally. Companies like Lockheed Martin, Raytheon, Northrop Grumman, and BAE Systems are trading 15%–37%+ YTD. The sector […]