GPS Jamming and Spoofing: How Modern Conflicts Degrade PNT

Satellite navigation became infrastructure without anyone voting on it. Aircraft, ships, cell towers, power grids, financial networks, precision munitions, and small drones all lean on the same faint signals from medium Earth orbit. For two decades that dependence was mostly a theoretical concern raised in conference papers and threat briefings. Since 2022 it has become an operational fact, visible on public flight-tracking maps and in airline safety bulletins.

The war in Ukraine, Russian activity around Kaliningrad and the Baltic, the conflicts involving Israel, Iran, and their neighbors, and the contest in the Black Sea have produced the largest sustained interference with global navigation satellite systems (GNSS) seen outside a test range. Some of it is aimed at weapons. Much of it spills onto civil aviation and shipping that have nothing to do with the fight.

This article walks through why GNSS signals are so easy to disrupt, how jamming differs from spoofing and meaconing, what the public record shows about recent incidents, what the effects look like for military and civil users, and what the detection, mitigation, and policy responses are. It relies only on open sources, and where numbers are cited they are attributed to whoever produced them.

How GNSS signals work, and why they are weak at the receiver

GPS, Russia's GLONASS, Europe's Galileo, and China's BeiDou all work on the same basic principle. Each satellite carries precise atomic clocks and broadcasts a signal that encodes the time of transmission along with data describing the satellite's orbit. A receiver measures when each signal arrives, converts the delay into a range (a "pseudorange," because the receiver's own clock is not perfect), and solves for four unknowns: three position coordinates and its own clock error. That is why a receiver needs at least four satellites in view for a full solution.

The timing part matters as much as the positioning part. Many users who never look at a map still depend on GNSS: cellular base stations, electric grid synchronization equipment, data centers, and financial systems use GNSS receivers as a cheap, accurate source of Coordinated Universal Time. Positioning, navigation, and timing (PNT) is the umbrella term, and timing is the piece most often forgotten.

A whisper from 20,000 kilometers

GPS satellites orbit at roughly 20,200 kilometers altitude. By the time the civil L1 C/A signal reaches the ground, the GPS interface specification (IS-GPS-200) sets the minimum received power at about -158.5 dBW, or roughly -128.5 dBm. For comparison, the thermal noise in the couple of megahertz of bandwidth a basic receiver uses sits near -111 dBm. In plain terms, the signal arrives well below the noise floor. Inside GNSS describes typical carrier-to-noise density values of roughly 37 to 45 dB-Hz for an L1 C/A receiver, which translates to a signal-to-noise ratio of roughly -21 to -29 dB across the front-end bandwidth.

Receivers recover the signal anyway because of spread-spectrum processing. Each satellite modulates its signal with a known pseudorandom code. The receiver generates a local replica and correlates it against the incoming noise, which concentrates the satellite's energy and pushes everything else down. That processing gain is what makes GNSS work at all, and it also sets the ceiling on how much interference a receiver can tolerate. A jammer close to the receiver does not need to be powerful in absolute terms. It only needs to deliver more energy in-band than the correlation gain can overcome, and a transmitter tens of kilometers away has an enormous geometric advantage over a satellite more than 20,000 kilometers away.

Known structure, open formats

The second weakness is that civil GNSS signal structures are published. That openness is the reason a cheap chip in a phone can use GPS, and it is also the reason a capable adversary can generate signals that look authentic. The civil signals carry no cryptographic authentication in their legacy form. Galileo has introduced an open service navigation message authentication capability, and the U.S. military M-code signal is encrypted, but the overwhelming majority of receivers in civil aircraft, ships, vehicles, and infrastructure still process unauthenticated civil signals.

Jamming, spoofing, and meaconing

All three are forms of electromagnetic attack (EA) against PNT, one of the three divisions of electromagnetic warfare alongside electromagnetic support (ES) and electromagnetic protection (EP). Older U.S. doctrine used "electronic warfare" and "electronic attack"; current joint doctrine uses "electromagnetic."

Jamming

Jamming is the transmission of energy in the GNSS bands to drown out the real signals. It is a denial technique. The receiver loses lock, reports degraded accuracy, or stops producing a solution. Jamming is relatively easy to detect because the receiver knows something is wrong: signal-to-noise ratios drop, satellites disappear, and integrity flags change.

Jammers range from small "personal privacy devices" plugged into a vehicle lighter socket to truck-mounted military systems. RUSI researcher Thomas Withington, quoted by The Defense Post in 2023, pointed to the Russian R-330Zh Zhitel as an example of a system whose coverage includes the GNSS bands and suggested that "the problem may well be the sheer power of the jamming signal that can be brought to bear."

Spoofing

Spoofing is the transmission of counterfeit GNSS signals designed to be accepted as genuine. It is a deception technique. A successful spoofer captures the receiver's tracking loops and then walks the reported position or time away from the truth. Unlike jamming, the receiver may report a confident, healthy solution that happens to be wrong. University of Texas aerospace engineering professor Todd Humphreys described the difference in a 2024 NPR interview: "Instead of just jamming the signals and breaking the links with GPS satellites, they're spoon-feeding them false signals."

In practice, much of the wide-area spoofing seen since 2023 is crude by laboratory standards. It often places victims at a fixed false location, such as an airport, rather than generating a carefully consistent false trajectory. That crudeness makes it easier to recognize after the fact, but it does not make it harmless. Aircraft and ship systems were built on the assumption that GNSS is either present and correct or absent, and the "present but wrong" case is where the design assumptions break.

Meaconing

Meaconing is an older term from the radio-beacon era. It refers to intercepting and rebroadcasting navigation signals, with or without delay, so that a receiver computes a position or bearing based on the rebroadcast rather than the original source. Applied to GNSS, a meaconer records the real satellite signals at one location and replays them elsewhere. The signals are authentic in structure, including any encryption, so meaconing is a way to attack receivers that cannot be fooled by a synthetic spoofer. Its limitation is that the replayed signals carry an extra delay and the geometry of the recording site, which a well-designed receiver can sometimes detect.

Ukraine and Russia: PNT as a front-line contest

The war in Ukraine is the clearest public example of GNSS interference as a routine combat function rather than an exotic capability. Both sides jam, both sides adapt, and both sides field weapons designed to keep working when satellite navigation is degraded.

Density of Russian electromagnetic warfare

In its May 2023 report "Meatgrinder: Russian Tactics in the Second Year of Its Invasion of Ukraine," the Royal United Services Institute (RUSI) assessed that Russian electromagnetic warfare remained potent, with "at least one major system covering each 10 km of front." The same report estimated Ukrainian unmanned aircraft losses at approximately 10,000 per month, a figure that covered all causes of loss but that RUSI tied closely to Russian jamming and spoofing of drones. These are RUSI estimates based on field research, not official figures, and they describe a particular period of the war.

Effects on Western precision munitions

In May 2024, The Washington Post reported on confidential internal Ukrainian assessments, prepared between fall 2023 and April 2024 and shared with Western supporters. According to the Post's reporting, the success rate of U.S.-designed Excalibur GPS-guided artillery shells fell over a period of months to less than 10 percent hitting their targets. The same reporting described Joint Direct Attack Munition (JDAM) kits losing effectiveness within weeks of their introduction in early 2023, with hit rates improving after manufacturers supplied upgraded guidance, and described jamming causing guided rockets from HIMARS launchers to miss by 50 feet or more in some cases. These are one party's internal assessments as relayed by a newspaper, and they describe a snapshot, not a final verdict.

The lesson the U.S. defense community drew is not that GPS-aided weapons are useless. It is that a weapon whose accuracy depends on uninterrupted GNSS during terminal guidance can be degraded by a capable adversary, and that the degradation can happen faster than acquisition timelines can respond. Kits that tightly couple GNSS with inertial measurement, that use anti-jam antennas, or that add terminal seekers fare better, at higher cost.

Adaptation on the other side

Russia has faced the same problem with its own long-range drones. Ukrainian officials and radio specialists have publicly described Shahed-type (Geran) drones recovered with controlled reception pattern antennas (CRPAs), multi-element arrays that can steer nulls toward jammers. According to reporting that cited Ukrainian air force spokesperson Col. Yuriy Ihnat and radio specialist Serhii "Flash" Beskrestnov, these included a Russian 12-element antenna known as Kometa and later Chinese-made arrays, with a 16-element version reported after earlier 8-element types. As Ihnat put it, "If there were previously eight channels, now there are 16, which means our electronic warfare systems must suppress them." A NATO Joint Analysis and Lessons Learned Centre publication has also addressed Kometa CRPA manufacturing in Russia.

The Baltic region and Kaliningrad

Since 2022, the airspace and sea lanes around the Baltic have seen persistent GNSS interference that European officials attribute to Russia, particularly to systems around the Kaliningrad exclave and in western Russia. Russia has not acknowledged responsibility for interference affecting civil users.

Aviation effects

The most concrete public example is Tartu, Estonia. In late April 2024, two Finnair flights diverted after GPS interference, and Finnair suspended its service to Tartu from April 29 to May 31, 2024. The reason was specific: Tartu's approach procedures at the time required a GPS signal, and the airport lacked the ground-based alternatives that larger airports have. Finnair's Director of Operations said, "as the approach to Tartu currently requires a GPS signal, we cannot fly there in the event of GPS interference." Estonia's foreign minister described the interference as part of Russia's hostile activities, and Lithuania's foreign minister compared it to someone switching off a driver's headlights at night.

The problem did not go away. Lithuanian public broadcaster LRT reported in June 2025 that aircrew reports of GPS interference in January 2025 were about ten times the level of January 2024, before declining in the following months. In the same reporting, Lithuanian parliamentary speaker Saulius Skvernelis said the interference stems from Russian efforts to protect Kaliningrad from potential air attack and that the protection zone extends beyond the region's borders. LRT also noted that thirteen EU member states had asked the European Commission to act, describing the interference as "systematic and deliberate action by the Russian and Belarusian regimes."

On August 31, 2025, a chartered aircraft carrying European Commission President Ursula von der Leyen experienced GPS jamming on approach to Plovdiv, Bulgaria. A Commission spokesperson confirmed the jamming and said the aircraft landed safely. Bulgarian authorities said they suspected Russian interference, and the Kremlin denied it. The Financial Times reported that the crew used paper maps.

Maritime effects and mobile emitters

Interference over the Baltic is not limited to land-based sources. In an analysis of Baltic interference in 2024 and 2025, Spire, which operates a commercial satellite constellation that collects radio-frequency data, described an October 2024 episode in which aircraft navigation integrity indicators collapsed over parts of the sea while most aircraft in the region were unaffected. Spire cited Gdynia Maritime University monitoring that recorded 84 hours of GNSS disruption over six months, 29 of them in October, with stretches of up to seven hours in which GPS, GLONASS, Galileo, and BeiDou were all disrupted. Spire assessed that the spatial pattern was more consistent with ship-borne jammers in international waters than with fixed sites on land.

The Eastern Mediterranean and Middle East: aviation spoofing at scale

Northern Iraq, September 2023

In late September 2023, the flight operations community OPSGROUP began collecting reports from crews on airway UM688 in northern Iraq, near Erbil, Sulaymaniyah, and Baghdad, close to the Iranian border. Aircraft received spoofed GPS signals that caused their navigation systems to show positions far from reality. OPSGROUP documented at least 20 cases in the initial period. In one widely reported case, an Embraer Legacy 650 lost GPS on both the aircraft and the crew's tablets, its inertial reference system also failed, and it ended up roughly 80 nautical miles off course. Crews resolved the situations with help from air traffic control, but one aircraft came close to entering Iranian airspace without clearance. The FAA issued a warning on September 28, 2023, citing safety-of-flight risk to civil aviation.

The detail that alarmed operators was the inertial failure. OPSGROUP's analysis explained that modern inertial reference systems take periodic GPS updates to bound their drift. If the GPS is simply jammed, the inertial unit coasts from its last good position. If the GPS is spoofed, the inertial unit may accept the false position as truth and update itself accordingly. Crews reported both inertial units losing position and, in some cases, aircraft clocks being corrupted. One technical pilot's advice, quoted by OPSGROUP, was to "disable GPS inputs at the very beginning of spoofing," which assumes the crew recognizes it in time.

Israel and the Eastern Mediterranean

After the October 2023 Hamas attack, the Israel Defense Forces confirmed that they were restricting GPS for defensive purposes, against the threat of guided rockets, missiles, and drones. Researchers including Humphreys and his students traced spoofed signals in the region to an Israeli military airbase, according to NPR's 2024 reporting. The false signals frequently placed receivers at Beirut's international airport. The effects reached airliners over the Eastern Mediterranean, ships near Israeli and Lebanese ports, and consumer apps on the ground.

Scale in 2024

OPSGROUP convened a GPS spoofing workgroup in July and August 2024 and published its final report in September 2024. The report stated that "on average 1500 flights per day are now spoofed, versus 300 in Q1/Q2 of 2024," and listed affected regions including the Mediterranean, the Black Sea, Russia and the Baltics, the India and Pakistan border, the Middle East, and western Ukraine. In a survey of about 2,000 crew members conducted by the workgroup, roughly 70 percent rated the impact of GPS spoofing as very high or extreme.

Maritime position anomalies: the Black Sea and beyond

Ships were among the first civil victims of documented wide-area spoofing, and maritime data offers one of the best public records of it because of the Automatic Identification System (AIS). AIS transmits a vessel's GNSS-derived position, so when GNSS is spoofed, the AIS track shows it to the world.

Gelendzhik, 2017

On June 22, 2017, the master of a vessel off Novorossiysk in the Black Sea reported that his GPS showed the ship more than 32 kilometers inland, at Gelendzhik Airport. The incident was reported through the U.S. Maritime Administration, and AIS traces showed about 20 vessels displaying the same false location.

The C4ADS analysis

In April 2019, the Washington-based nonprofit C4ADS published "Above Us Only Stars," an analysis of AIS and other public data. It identified nearly 10,000 suspected spoofing events affecting more than 1,300 civilian vessels over roughly two years, with clusters in the Black Sea, the Eastern Mediterranean near Syria, the Gulf of Finland, waters off Vladivostok, and Russian territorial waters. C4ADS also reported a correlation between some spoofing events and the movements of Russian President Vladimir Putin, suggesting that spoofing was being used for VIP protection.

2024 and 2025

The pattern widened as conflicts spread. Lloyd's List reported in April 2024 that on a single day, 117 cargo vessels falsely appeared at Beirut-Rafic Al Hariri International Airport and 45 appeared at Cairo International Airport, and that 227 vessels in the Black Sea showed disrupted AIS positions across multiple land locations on another day. Lloyd's List Intelligence analysts linked the activity in different regions to different suspected actors, including Israeli forces in the Eastern Mediterranean, Russia in the Black Sea, and Iran or Iran-linked groups in the Red Sea and Gulf.

During and after the June 2025 strikes involving Israel, Iran, and the United States, interference spiked in the Persian Gulf and the Strait of Hormuz. Maritime intelligence firm Windward, as reported by Freight News, described a 60 percent surge in GPS interference over one weekend, with about 1,600 vessels affected and, at peak, nearly a quarter of vessels in the region disrupted within a 24-hour window. QatarEnergy suspended night-time sailings near Mesaieed because of safety concerns.

Effects on military and civil users

Military users

For military forces, GNSS interference is an expected condition, and doctrine and training already assume it. The issues are degree and cost. Precision munitions lose accuracy if their anti-jam margin is exceeded. Small drones that depend on commercial GNSS modules lose their ability to hold position, return home, or reach a waypoint. Forces that rely on GNSS timing for communications networks and cryptographic synchronization can lose links.

Civil aviation

Civil aircraft are designed around a navigation architecture where GNSS is one of several sources, alongside inertial reference systems and ground-based aids such as VOR, DME, and ILS. Jamming generally produces a recognized loss of GNSS, and crews revert to other means. The problems documented by OPSGROUP, the FAA, and EASA include:

Loss of area navigation capability on routes or approaches that depend on GNSS, as at Tartu.
Corruption of inertial reference positions when spoofed GNSS updates are accepted.
False terrain awareness and warning system alerts, including pull-up warnings, when the aircraft believes it is somewhere it is not.
Corrupted aircraft clocks and timing, which can affect other systems that use time.
Degraded ADS-B position reports, which affect surveillance by air traffic control and other aircraft.
Higher workload for crews and controllers, particularly in busy airspace near conflict zones.

Maritime

Ships integrate GNSS into the electronic chart display, AIS, the gyrocompass correction, and often the autopilot. Spoofing can move the ship's own displayed position, shift other vessels' AIS positions, and affect collision-avoidance calculations. In crowded waters such as the Strait of Hormuz, the Suez approaches, or the Bosporus, a bridge team that loses trust in GNSS has to fall back on radar and visual navigation at a time when traffic density gives little margin for error.

Timing users on the ground

Ground-based timing users are the least visible group. A cell site or substation that loses GNSS can usually hold time on a local oscillator for a period that depends on the quality of that oscillator. A spoofed timing receiver is worse than a jammed one because it can steer the local clock to a wrong time without raising an alarm. This is the scenario that drove much of the U.S. federal policy work on PNT resilience.

Detection and mitigation

No single technology makes a receiver immune to interference. The practical approach is layered: reduce how much interference reaches the receiver, make the receiver better at telling real from fake, give it other ways to navigate when GNSS is unreliable, and build the monitoring to know where interference is occurring.

Antennas: CRPAs and null steering

A conventional GNSS antenna receives from the whole sky. A controlled reception pattern antenna uses multiple elements and signal processing to shape its gain pattern, steering nulls toward interference sources and, in more capable designs, steering beams toward satellites. Because jammers usually sit near the horizon and satellites are distributed across the sky, a CRPA can suppress a small number of jammers by tens of decibels while keeping enough satellites in view. The number of elements roughly limits how many independent interference sources the array can null, which is why the move from 8-element to 16-element arrays on Shahed-type drones was treated by Ukrainian officials as significant.

M-code and military receivers

M-code is the modernized GPS military signal. It is encrypted, which addresses spoofing by making counterfeit signals hard to generate, and it was designed to improve resistance to jamming compared with legacy military signals. M-code-capable satellites have been in orbit for years. In 2020, GPS World reported that 21 operational GPS satellites were M-code capable, including the first GPS III satellites.

The constraint has been the rest of the system. In its September 2024 report "GPS Modernization: Delays Continue in Delivering More Secure Capability for the Warfighter" (GAO-24-106841), the Government Accountability Office noted that DoD has spent more than 20 years developing M-code and that the ground control and user equipment segments have repeatedly slipped. The first increment of Military GPS User Equipment, the chips and cards that process M-code, was approaching its final tests, but GAO reported newly discovered deficiencies, integration challenges across the military departments, and risks to schedule. Until M-code receivers are fielded broadly across platforms and munitions, the protection the signal offers remains partly theoretical for many units.

Sensor fusion with inertial navigation

Inertial navigation systems measure acceleration and rotation and integrate them to track position. They cannot be jammed or spoofed by radio, but they drift, and the rate of drift depends heavily on sensor quality and cost. GNSS bounds that drift. The combination, usually through a Kalman filter, gives the best of both: GNSS supplies long-term accuracy, and the inertial unit supplies short-term continuity and a reference against which GNSS measurements can be checked.

The September 2023 Iraq incidents show the trap. If the fusion logic trusts GNSS too much, a spoofed GNSS input contaminates the inertial solution, and the system loses its independent reference. Better integration means checking GNSS measurements against the inertial prediction and rejecting jumps that are physically implausible.

Beyond inertial units, other sensors add independence:

Terrestrial radio aids such as DME, VOR, and ILS in aviation, and the case for preserving them, which every major aviation body has made.
Vision-based and terrain-referenced navigation, comparing camera or radar data against stored maps.
Signals of opportunity, including low Earth orbit communications satellites and terrestrial broadcasts, which researchers have demonstrated as positioning sources.
Stable local clocks, such as oven-controlled crystal oscillators and chip-scale atomic clocks, which let timing users hold time through outages.

Receiver-level spoofing detection

Receivers can look for spoofing in several ways: checking whether all signals arrive from the same direction (a single transmitter) rather than from different satellites, watching for sudden jumps in signal power or clock offset, cross-checking constellations and frequencies against one another, and using authenticated signals where available, such as Galileo's open service navigation message authentication. None of these is perfect on its own, and many fielded civil receivers implement few of them. The DHS Resilient PNT Conformance Framework, discussed below, was written partly to give buyers a common way to describe what level of resilience they need.

Monitoring networks

Knowing where interference is happening is a mitigation in itself, because it lets operators plan routes and fuel, issue notices, and coordinate responses. Several kinds of monitoring are now in use:

Crowdsourced ADS-B analysis. Aircraft broadcast navigation integrity and accuracy indicators in their ADS-B messages. GPSJam, built by John Wiseman, aggregates these from the community-run airplanes.live and ADS-B Exchange receiver networks and maps the share of aircraft reporting low accuracy each day. Its own FAQ notes the limitations: it cannot distinguish jamming from spoofing, effects at altitude may not reach the ground, and coverage depends on where aircraft fly and receivers exist.
AIS analysis. Maritime analysts such as Windward, Lloyd's List Intelligence, and C4ADS use AIS anomalies, such as ships "appearing" at airports or in circular patterns, to detect spoofing at sea.
Space-based RF collection. Commercial operators such as Spire and others collect radio-frequency data from low Earth orbit and publish analyses of interference patterns, including attempts to localize emitters.
Government reporting channels. The U.S. Coast Guard Navigation Center accepts GPS problem reports, air traffic control and NOTAMs carry aviation reports, and European authorities coordinate through EASA and EUROCONTROL.

Regulatory and policy responses

Responses fall into two broad groups: operational guidance for aviation and maritime users who must deal with interference now, and longer-term policy aimed at reducing dependence on a single source of PNT.

Aviation advisories, 2022 to 2025

EASA first issued Safety Information Bulletin 2022-02 on GNSS outages and alterations on March 17, 2022, weeks after Russia's full-scale invasion of Ukraine, and has revised it several times since, including in July 2024. The bulletin covers pilot and controller procedures, reporting, operator risk assessment, and the importance of retaining conventional navigation aids. EASA and EUROCONTROL have also set up a joint task force on the issue.

In the United States, the FAA issued Safety Alert for Operators (SAFO) 24002 in early 2024. It distinguished jamming from spoofing, warned of "possible loss of situational awareness and increased pilot and regional ATC workload issues," and advised crews to check NOTAMs, plan fuel contingencies, monitor equipment for discrepancies, use conventional navigation aids, be prepared to operate without GPS, and report disruptions promptly.

On March 25, 2025, three United Nations agencies, the International Civil Aviation Organization (ICAO), the International Telecommunication Union (ITU), and the International Maritime Organization (IMO), issued a joint statement urging states to protect radionavigation satellite services from harmful interference. The statement called for states to prevent interference with civil and humanitarian use, strengthen the resilience of systems that depend on satellite navigation, maintain conventional navigation infrastructure as a backup, improve coordination among regulators, aviation and maritime authorities, defense, and enforcement agencies, and establish reporting mechanisms. ICAO Secretary General Juan Carlos Salazar noted that interference "can impact aircraft operations far beyond the immediate affected area."

EASA and the International Air Transport Association (IATA) followed a May 2025 workshop in Cologne with a joint plan organized around four areas: better reporting and monitoring, prevention and mitigation (including export and licensing controls on jamming equipment and technical work to reduce false terrain warnings and speed receiver recovery), retention of conventional navigation infrastructure and contingency procedures, and improved civil-military coordination and data sharing. According to GPS World's coverage of the plan, GPS signal loss events increased by 220 percent between 2021 and 2024.

Executive Order 13905

In the United States, the main policy instrument is Executive Order 13905, "Strengthening National Resilience Through Responsible Use of Positioning, Navigation, and Timing Services," signed on February 12, 2020. The order defines "responsible use" of PNT services as the deliberate, risk-informed use of those services so that their disruption or manipulation minimally affects national security, the economy, public health, and critical functions of the federal government.

Among its provisions, the order:

Directed the Secretary of Commerce to develop and make available PNT profiles that help organizations identify systems that depend on PNT, detect disruption and manipulation, and manage the associated risk, with the profiles to be reviewed and updated over time.
Directed the Secretary of Homeland Security to develop a plan to test the vulnerabilities of critical infrastructure systems to PNT disruption and manipulation.
Directed agencies to incorporate the profiles into contracting requirements for PNT-dependent systems, with a role for the Federal Acquisition Regulatory Council.
Required the Departments of Defense, Transportation, and Homeland Security to reference the profiles in updates to the Federal Radionavigation Plan.
Called for pilot programs with critical infrastructure owners and operators and for a coordinated research and development plan for alternatives to GNSS-based PNT.

NIST produced the Foundational PNT Profile, NISTIR 8323, in February 2021 and replaced it with Revision 1 in January 2023. The profile applies the five functions of the NIST Cybersecurity Framework (Identify, Protect, Detect, Respond, and Recover) to PNT dependence. NIST is explicit that the profile is voluntary and that following it "will not necessarily protect organizations from all PNT disruption or manipulation."

DHS work

The Department of Homeland Security's Science and Technology Directorate, working with the Cybersecurity and Infrastructure Security Agency, developed the Resilient PNT Conformance Framework, now at version 2.0. It defines four levels of resilience for PNT user equipment, so that buyers can specify what behavior they need under disruption and manipulation. DHS later transitioned the framework to the IEEE, where it forms the basis of IEEE P1952, "Standard for Resilient Positioning, Navigation and Timing (PNT) User Equipment." A line from DHS describing the framework's philosophy captures the shift in thinking: GPS and PNT receivers "need to be treated more like computers rather than radios."

DOT work on complementary PNT

The Department of Transportation has led the federal effort to assess technologies that could complement or back up GPS. In January 2021, DOT released a report on a 2020 field demonstration, run by the Volpe National Transportation Systems Center at NASA's Langley Research Center and Joint Base Cape Cod, that evaluated 11 candidate technologies against 14 criteria. The report concluded that mature, commercially available technologies could support timing when GPS is unavailable, that no single system can replace GPS for positioning and navigation, and that a diverse portfolio offers the best path to resilience.

DOT published its Complementary PNT Action Plan in September 2023. According to Volpe, DOT awarded more than $7 million to nine technology vendors in June 2024 for a rapid phase of field testing, completed that testing in June 2025, presented initial results at an interagency workshop in August 2025, and delivered a final report on the first rapid phase in March 2026.

FCC

The Federal Communications Commission adopted a Notice of Inquiry on alternative PNT technologies in March 2025. Chairman Brendan Carr framed the issue directly: "Continuing to rely so heavily on one system leaves us exposed." The inquiry sought comment on space-based options in medium and low Earth orbit, terrestrial systems, and receiver technology resistant to jamming and spoofing, along with the spectrum, security, and international coordination questions those options raise.

What to watch

The open record since 2022 supports a few plain conclusions. GNSS interference is now a normal feature of conflict, not an edge case. It spills far beyond the battlefield into civil aviation, shipping, and potentially ground infrastructure. Spoofing, not just jamming, is happening at scale against civil users. And both attackers and defenders are adapting faster than formal acquisition and certification processes typically move.

Several developments are worth tracking:

M-code fielding. Whether DoD closes the gaps GAO identified and gets M-code receivers into platforms and munitions at scale, not just into test articles.
Anti-jam proliferation. How quickly CRPA technology spreads to cheaper drones and munitions, and whether export controls on both jammers and anti-jam antennas have any measurable effect.
Civil avionics standards. Whether certification standards evolve to require better spoofing detection, faster post-spoofing recovery, and fewer false terrain warnings, as the EASA and IATA plan contemplates.
Retention of ground-based aids. Whether states keep enough VOR, DME, and ILS infrastructure to serve as a backup, given the cost pressure to retire it.
Complementary PNT decisions. Whether DOT's testing and the FCC's inquiry lead to concrete decisions on terrestrial or LEO-based alternatives, including spectrum.
Timing resilience in critical infrastructure. Whether operators actually use the NIST profile and DHS framework to find and fix GNSS timing dependencies before an incident does it for them.

For program offices and engineers, the practical takeaway is that assumed GNSS availability should be treated as a design risk, not a baseline. Requirements, test plans, and operational assessments that do not include degraded, denied, and deceived PNT conditions are not testing for the environment that current conflicts are actually producing. What specific military capabilities exist beyond what is described in public sources is not publicly known, and this article does not speculate about it.