Photo: Courtesy of oneNav.
As warfare becomes more high-tech and billions continue to be invested into smart weapons, an Achilles’ heel has emerged in America’s defense capabilities – the 50-year-old GPS L1 signal.
GPS L1 interference is happening in conflict zones around the world and is thwarting even the most advanced weapons on the battlefield. In Ukraine, Russian forces are jamming American weapons, including drones and missiles that rely on GPS, a major blow to Ukraine’s counteroffensive.
This interference isn’t limited to the battlefield. Russia is also accused of interfering with civilian aircraft GPS systems throughout Eastern Europe, as evident in more than 40,000 flights experiencing navigation issues over a six-month period. GPS interference is also taking place in and around other conflict zones in the Middle East.
However, what is most worrying are experts’ concerns about the resilience of GPS in the event of any potential Chinese escalation around Taiwan. China has increased its military activities around the island in recent years and its warships are accused of interfering with civilian airplanes’ GPS systems throughout the Asia Pacific. GPS jamming is already being used as a weapon in today’s wars and we should be prepared for it to be used in the conflicts of tomorrow.
The prevalence of GPS interference is due in part to America’s reliance on outdated GPS technology that can easily be compromised by our adversaries. First invented more than 50 years ago, these initial GPS signals – known as L1 – played an essential role in bringing this technology to billions of people around the world. However, the development of new and superior signals – especially those in the L5 band – has made these legacy signals outdated.
Modern L5-band signals are cleaner, higher-quality, and broadcast at higher power using higher bandwidth – all attributes that increase its resilience to jamming. Additionally, they incorporate coding gain and error correction, enhancing their resilience against multipath interference.
However, despite these superior signals being broadcast from satellites for the past decade, the L5 band is not fully utilized in our modern technology devices – including those used on the battlefield.
Currently, most civilian and some military devices use hybrid or dual-frequency signals, meaning a combination of both L1 and L5. In theory, upgrading from L1 to dual frequency should improve performance, but the reality is that our devices still overwhelmingly rely on outdated L1 signals, even in a hybrid system.
This is because dual-frequency processors, including those which are L5 compatible, must obtain the L1 signal before accessing L5. Meaning that, despite utilizing the modern GPS L5 signals, current devices are constrained by legacy L1 signals – and the vulnerabilities that come with them. Currently, if such devices lose the L1 signal, rarely can they acquire and navigate by L5 alone. In a conflict zone, this can be the difference between mission success and failure.
While America’s military operates its own dedicated GPS signal, known as M Code, many allies cannot access these signals. The same is true for many military contractors, relied upon for crucial services such as logistics and supply chains. Third-party contractors and the owners and operators of our national critical infrastructure (energy, rail, ports, aviation, etc.) do not have access to classified military receivers and completely rely on civilian GPS signals – the same signals that are being jammed in conflict zones around the world. Any suggestion that the military is not affected by interference with civilian GPS signals is simply incorrect.
Photo: Courtesy of oneNav.
Recent advances in technology can reduce our reliance on L1 signals while providing a low SWaP (space, weight and power) solution that improves GPS performance, reliability, and most importantly, safety and security.
GPS technology developer oneNav has successfully developed L5-direct™, a new GPS product category capable of directly acquiring and tracking L5-band signals without first having to acquire L1.
The benefits of direct acquisition of L5 signals are enormous, particularly for developers of defense technology. These signals offer superior performance in difficult-to-navigate areas such as urban canyons and tree-covered regions and are broadcast from 46 satellites operated by the U.S. and our allies, providing more than sufficient global coverage.
Most importantly, these signals are 30x harder to jam and interfere with compared to the original L1. This means these modern signals will have a significantly smaller interference radius when encountering future L5 jamming transmissions – essentially creating a much smaller target for bad actors to attempt to interfere with that would require approximately 20x more power to jam the same area.
Multiple field studies in GPS-contested environments confirm the resilience of L5 signals. Most recently, an April 2024 field study conducted by oneNav near the Polish/Russian border compared the performance of L1 and L5 signals in areas with frequent GPS interference. While researchers observed widespread jamming of L1 signals across the region, from Finland to Turkey, signals that directly acquired the L5 band demonstrated immunity to L1 jamming.
The resilience of L5-direct™ to widespread jamming in Ukraine should be a blueprint for countering GPS jamming in other conflict zones. As the war in the Middle East risks expanding and tensions continue to rise around Taiwan, GPS resilience must be front and center when considering defense tech capabilities.
L5-direct™ provides the opportunity to better protect our most essential military technologies from bad actors looking to exploit outdated L1 technology, and it provides far more accurate PNT services in the process. This technology can also be used in industries where GPS systems are under assault, such as aviation, where the operational and financial stakes of GPS interference are enormous.
oneNav’s silicon-proven L5-direct™ technology is currently available for evaluation and integration by chip developer partners and is compatible with a wide range of defense tech devices including drones, artillery shells and handheld radios, and for personal location devices such as smartwatches, low-power trackers and more.
If you would like to learn more about the next generation of location services, please visit oneNav.
Steve Poizner is the CEO of oneNav, Inc., a GPS technology development company.
