A wave of GPS jamming and spoofing has sent commercial airliners and business aircraft off-course while flying over the Middle East and northern Europe, raising concerns about the safety of air travel worldwide. Intelligence analysts widely believe the interference originates from hostile states including Iran and Russia and their surrogates.
In airspace where jamming occurs, aircraft operators experience a degradation of their Global Navigation Satellite Systems (GNSS) as receivers cannot latch onto satellite signals. Spoofing involves sending out bogus satellite signals to deceive GNSS receivers into computing erroneous position, navigation, and timing information.
Jamming and spoofing have become common in military conflict zones, such as in the Middle East and over the Black Sea. Israel first suffered from GNSS service denial when the Russian forces in Syria operated some powerful jamming systems. The war in Ukraine also created a wide area of airspace where operators cannot trust the GNSS signals.
The capability of armed forces to deny access to the GNSS service prompted some countries to invest in technologies aimed at enabling their military forces to continue their reliance on GNSS-based navigation. The U.S. operates the GPS navigation system, which uses a dedicated constellation of medium Earth orbit (MEO) satellites.
GPS anti-jamming systems protect against deliberate jamming and interference for GPS receivers. When the GPS signal gets to the surface of the Earth, stronger radio frequency (RF) energy can overpower it. A tiny jammer with a power of around 10 watts for up to 30 kilometers (19 miles) of line of sight can interfere with an unprotected code receiver.
Until recently, armed forces mainly have used anti-jamming systems, but increasingly the civil aviation sector has realized it needs protection from GPS service denial.
In early 2024, the frequent disturbances to GPS systems in the Middle East and Ukraine prompted an effort of the civil aviation regulatory bodies to address possible solutions to the worsening problem. In January, the International Air Transport Association and European regulator EASA hosted a meeting at the latter’s Cologne, Germany, headquarters.
Multiple aerospace and defense groups have risen to the challenge of applying technology that generally has originated in the military sector to protect civil aircraft.
Industry Innovates to Block Jammers and Spoofers
Most of the major technological companies have begun investing in anti-jamming systems. For instance, RTX group business Collins Aerospace now offers a system that can integrate with a GPS receiver or operate on a standalone basis. It secures GPS signals in dense electromagnetic environments and rejects spoofed GPS signals. Sister company Raytheon also offers a portfolio of anti-jamming systems to guard against a variety of hostile jammers.
UK-based group Cobham has developed an anti-jamming system that combines advanced controlled radiation pattern array (CRPA) antenna technology with intelligent digital signal-processing techniques. The company has actively developed the technology for more than a decade.
In Canada, NovaTel’s GPS Anti-Jam Technology has been used in combat conditions to deliver an assured positioning, navigation, and timing (APNT) solution that protects navigation systems from radio frequency interference and jamming. In the U.S., Mayflower Communications Company offers its NavGuard Anti-Jam Systems.
According to Israeli defense and industry sources who talked with AIN on condition of anonymity, Russia is helping Iran to upgrade its electronic warfare (EW) capabilities including GPS denial capabilities. Israel and its allies have closely monitored the development and remain concerned about the prospect of GNSS disruption against civil aviation as a means of covert warfare in tandem with threats such as those posed by Iranian surrogate Houthi forces to shipping in the Red Sea.
The same source indicated that Russia has shared with Iran lessons it learned from EW and GPS denial operations in Syria while Israel’s air force attacked Iranian-related targets in the neighboring country. Those and earlier incidents have affected the operation of Israeli civil aircraft. The Russians have also passed along lessons learned from GPS-jamming actions in its conflict with Ukraine.
Israel Deploys Protection Against Iranian and Russian Threats
The proliferation of Russian-made GPS jamming systems in the Middle East led to the equipage of Israeli military aircraft with anti-jamming systems. In 2021, the Israeli air force revealed that advanced anti-jamming capability developed by Israel Aerospace Industries (IAI) has been integrated with EW defensive systems used by different squadrons. The system is the ADA Anti-Jam GPS System, designed to protect GPS/GNSS navigation from jamming
The technology now appears on platforms including F-16 fighters and multiple drones. The ADA system has demonstrated operational maturity and several undisclosed international customers use it on various airborne, land, and marine platforms. IAI now offers the technology to civil and military customers.
According to IAI, the ADA system maintains assured positioning, navigation, and timing (PNT) by overcoming GPS jamming and ensuring that the platform can continue to operate with consistent GNSS availability. ADA uses advanced digital signal processing techniques to provide high levels of immunity, even in severe and dynamic multi-jammer scenarios.
The ADA equipment’s modular architecture supports both Multi-GNSS and GPS M-Code. Systems can support either an integrated immune GNSS receiver or an independent RF add-on through RF connection to any third-party GNSS receiver (GPS, IRNSS, GLONASS, Galileo), thereby allowing a plug-and-play approach to installation.