Most modern technology, including smartphones, runs on GPS. But the system may be more vulnerable to failure than you think. The US has no backup technology for geolocation, which means that failures or interference could be catastrophic. Russia has threatened destruction GPS satellites and recently faulty GPS signals temporarily closed a Dallas airport.
Fortunately, companies are stepping in to monitor GPS. NextNav recently signed a deal to provide new technology called TerraPoiNT that backs up GPS, using existing LTE and 5G networks. “TerraPoiNT’s signal is over 100,000 times stronger than GPS, and its signal encryption makes it more resistant to jamming and spoofing,” Ganesh Pattabiraman, CEO of NextNav, told Digital Trends in an interview. It’s an intriguing statistic – and a glimpse into how we can (and should) protect GPS.
GPS provides positioning, navigation, timing and location services for mobile phones. Its widespread availability has made it a global utility that is an integral part of industries and infrastructure ranging from the power grid to 911 emergency services to financial transactions. But, Pattabiraman said, the system is “incredibly vulnerable” to interference — including glitches and spoofing.
Sam Brown, a professional radio engineer who runs a radio frequency blog at One SDRsaid in an interview that GPS communications receivers are often disrupted using readily available and inexpensive jammers.
“A jammer will send out a signal that interferes with signal reception, and as a result, the GPS receiver will not be able to provide location information,” he added.
In a recent example, problems with GPS signals led to flights being grounded at the Dallas/Fort Worth International Airport. The problem was traced to a mysterious source of interference and the airport closed for two days.
Possible foreign interference is another problem. Russia has boasted that it can take out the satellites that provide our GPS.
“An incident such as a major solar flare or damage to commercial satellites could potentially take out many essential services we rely on every day,” said Pattabiraman. Therefore, the U.S. federal government has recognized the importance of implementing alternative PNT technologies to ensure GPS resiliency, including through an executive order to “engage the public and private sectors in identifying and promoting responsible use of PNT services.
Alex Damato, acting executive director of the GPS Innovation Alliance, an industry group, said in an interview that his organization takes a technology-neutral stance when it comes to backup GPS solutions.
However, he said GPSIA agrees that “the best strategy for achieving a resilient PNT service is to pursue multiple technologies to promote diversity in the PNT functions.” It is also essential that backup solutions are capable of providing equivalent capabilities and performance comparable to GPS technologies and are driven by each industry’s PNT requirements rather than government mandates.
Part of the problems with GPS stem from its design as a relic of the Cold War. GPS was designed for military use in conflict zones where civilian networks weren’t available — firing missiles a thousand miles through the upper atmosphere or helping aircraft carriers cross the ocean, Integrated Roadways founder and CEO Tim Sylvester said in an interview. It was never intended to help pedestrians and vehicles navigate quiet urban areas.
“This mismatch in design versus use means that GPS has several key flaws, such as low accuracy and high latency,” Sylvester said. These challenges are a product of the GPS signals coming from satellites thousands of miles away, and the drawbacks are a consequence of physics that cannot be solved.”
GPS has its drawbacks when it comes to a new generation of self-driving cars. GPS’s low accuracy means you can’t use it effectively to know what lane someone is in, which is a big deal when driving, and high latency means your position information gets worse if you move quickly, which is also a big problem when driving, Sylvester said. Because GPS comes from thousands of miles away, in urban areas with lots of tall buildings, the accuracy is even worse because the tall buildings block satellites that aren’t exactly in the right position to transmit past the buildings.
“These limitations completely contradict the use of GPS for connected and autonomous vehicles, which require high accuracy, low latency and reliable operation in dense urban areas given how dense urban areas are where all the traffic is,” said Sylvester. “Just as newspapers were replaced by online news, GPS has been a great springboard, but it’s time to move beyond that. In fact, most apps are already ignoring GPS and quietly replacing it with alternatives like Bluetooth, but this is usually hidden from the user, as the user cares about good service, not how they get it.”
The coming wave of autonomous vehicles may require a better location system. Sylvester said the most promising alternative to GPS for connected and autonomous vehicles is called APNT. PNT stands for “position, navigation, telemetry.” Depending on who you ask, the “A” can stand for assisted, augmented, insured, alternate, or other near-synonyms.
APNT is built into local infrastructure, including cell antennas, Bluetooth beacons, Wi-Fi, or other “alternate” means to position, navigate, and receive vehicle telemetry.
“These methods have been cobbled together over the past 15 years using a combination of smartphone components and readily available communication methods, and while they’re great for tourists who wander Market Street or Times Square trying to find a sub-$30 sandwich, cost, their ad hoc nature means they can’t be relied upon for autonomy,” Sylvester said.
Integrated Roadways has developed Smart Pavement, which builds the APNT capabilities directly into the road, using high-precision road sensors and supported by an ultra-low latency edge network, “so that any road upgraded with Smart Pavement will have all the APNT capabilities needed for connected and autonomous vehicles built into the roadway and designed from the ground up as a reliable, secure, industrial-grade network that delivers the features needed for next-generation mobility demands,” said Sylvester
NextNav’s system isn’t the only option for GPS backup. Max Perez, the vice president of research and security solutions at ColdQuanta, said in an interview that Quantum Positioning Systems (QPS) have the potential to serve as an alternative to GPS. Quantum properties feed the positioning system and unlike GPS, QPS does not require constant calibration with outside signals to work.
“A QPS only needs to know the starting point to function and can calculate how fast it traveled, how long and in what direction to determine its current position,” Perez said. “Quantum Positioning Systems (QPS) would improve GPS around the world as it provides significantly improved navigational security. Use cases for QPS include navigation for aircraft, submarines, self-driving cars and more. Advantages of QPS over GPS include accuracy, no satellite dependence, indoor use and less vulnerability to hacking.”
Damato said the GPS industry is rapidly innovating and developing solutions that make GPS more accurate and resilient. These solutions include GPS receivers, the satellites that provide these GPS signals, and the ground control segment that tracks and monitors GPS performance.
“A major modernization of the GPS constellation is underway which, when completed, will yield dozens of new satellites offering significantly greater accuracy and improved anti-jamming capabilities,” he added.