PlanetiQ already provides NASA with ionospheric scintillation data, ionospheric total electron content measurements, and high-SNR GNSS radio occultation data under the program.

The expanded offering gives government researchers access to observations designed to improve understanding of precipitation processes, atmospheric structure, and Earth system dynamics. Polarimetric radio occultation extends traditional GNSS-RO by using dual-polarization receivers — capturing both horizontally and vertically polarized returns from circularly polarized GNSS signals. Because raindrops and snowflakes tend to flatten as they fall, the horizontally polarized component is slightly delayed relative to the vertical; measuring that phase difference yields information about rain and snowfall structure, melting layers, horizontal precipitation banding, and storm intensity variation.

PlanetiQ’s high-SNR receivers are central to the capability’s value for precipitation applications, where greater sensitivity to lighter precipitation and certain cloud structures is critical.

“As more researchers gain access to high-SNR PRO data, we expect both the scientific understanding and the potential operational uses of the technology for precipitation and severe weather monitoring to expand,” said Dr. E. Robert Kursinski, Chief Scientist of PlanetiQ.

Access through the CSDA program is available to NASA researchers, other U.S. government agencies, and international collaborators. PlanetiQ, founded in 2015 and based in Golden, Colorado, received NOAA’s largest-ever commercial satellite weather data contract in 2025, valued at $24.3 million, and holds a $15 million U.S. Air Force STRATFI contract for next-generation weather data from space.

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Announced June 17, Kestrel integrates Honeywell’s HG3900 MEMS Inertial Measurement Unit with an M-code receiver and a multi-GNSS receiver in a package the company says is 40 percent smaller and lighter than comparable EGI products on the market. The M-code capability provides access to the military GPS signal’s enhanced anti-spoofing and anti-jam protections, while the multi-GNSS receiver broadens the available constellation coverage under nominal conditions. When external signals are unavailable, the INS layer maintains self-contained navigation continuity.

The system is intended primarily for Group 2 and 3 collaborative combat aircraft and loitering munitions, where the combination of SWaP-C constraints and GNSS-denial risk is most acute, though Honeywell notes applicability to crewed platforms with similar constraints. The company claims up to 80 percent improvement in navigation accuracy over legacy systems and cost reductions of up to 50 percent — both figures are company-sourced. Kestrel will be available in non-ITAR configurations for international defense and commercial operators.

“This system helps operators maintain mission objectives in environments where legacy GPS systems are lagging behind,” said Matt Picchetti, vice president and general manager of Navigation & Sensors at Honeywell Aerospace. Honeywell has produced more than 60,000 EGI units since pioneering the technology in the mid-1990s.

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For Inertial Labs, the Virginia-based inertial navigation specialist acquired by VIAVI Solutions in 2025, that challenge has become the central driver of product development.

Speaking to Inside GNSS in Paris, Inertial Labs Sales Engineer Jackson Williams said his company has spent more than two decades refining inertial technologies while steadily expanding into sensor fusion and assured navigation. “We’re kind of a 25-year overnight success,” he quipped. The company started in 2001, based in Northern Virginia. “We also have manufacturing in Rapid City, South Dakota, and another R&D office in Kiev, Ukraine,” Williams said.

Over the past two decades, the company has evolved from a sensor manufacturer into a provider of complete navigation solutions. At the heart of that portfolio are gyroscopes and accelerometers, the foundational sensors that measure rotational and linear motion. Those are integrated into inertial measurement units (IMUs), which then form the basis of increasingly sophisticated inertial navigation systems.

Core competence

Williams summarized the company’s mission simply: “We do GPS&I, that is GPS plus inertial navigation, for autonomous vehicles. Starting with the base level sensors, we build our IMUs, and then create more complex inertial navigation systems out of those.” That focus has naturally led the company toward sensor fusion, using further data sources to constrain drift and improve overall navigation performance.

“Our main selling point and our kind of specialty is sensor fusion,” Williams said. “So we bring in aiding forms of data, such as air data computers, magnetometers for heading, fiber optic and man-time use, and low Earth constellation satellites for assured position and navigation and timing.”

Multiple aiding sources help constrain inertial drift and improve solution integrity. By fusing diverse, independent measurements, Inertial Labs seeks to maintain navigation performance in degraded environments, a sensor-diversity approach that Williams described as central to the company’s strategy.

“We bring in things like radio as well, line of sight, time of flight, time of arrival data,” he said. “We fuse these all together, curate them to our customers’ requirements, specifications, and support them when they’re on. We like to be very hands-on with our projects.”

Where it matters

Electronic warfare systems deployed particularly in Ukraine have demonstrated how vulnerable GNSS signals can be to interference. Modern assured-PNT architectures increasingly depend on multiple complementary sensors working together.

One example of a key aiding source is Inertial Labs’ miniature Air Data Computer (ADC). Designed for low size, weight and power consumption, the ADC provides airspeed, altitude and atmospheric measurements that can be fused with inertial data. For unmanned aircraft operating in dynamic flight conditions, those measurements provide an additional reference that helps maintain navigation accuracy during GNSS degradation or loss.

The war in Ukraine has also had a direct influence on product development. Inertial Labs’ Kiev office, originally established in 2006 as a conventional R&D center, now plays an important role in testing and validation. The value of that operational feedback has been significant. “All of our products are battlefield tested and qualified, vetted through our people in Ukraine,” he said. “And with everything that’s going on there, we’re getting a lot of feedback. That’s been a large factor in driving our innovation and our improvements in our devices.”

For many of the companies we met at Eurosatory, the war in Ukraine has become an unprecedented laboratory for navigation technologies. GNSS denial, electronic attack and contested electromagnetic environments have shifted inertial navigation from a backup capability to a central component of military positioning architectures.

Partnering in space

The emphasis on multiple, complementary navigation sources is also reflected in Inertial Labs’ work with the Iridium company. Iridium operates a global low-Earth-orbit (LEO) satellite constellation whose signals are increasingly being explored for resilient PNT applications. LEO-PNT satellites operating in low Earth orbit transmit significantly stronger signals than traditional medium-Earth-orbit GNSS constellations. Inertial Labs’ partnership with Iridium emerged publicly in 2026 with the introduction of IRINS, a system that combines Inertial Labs’ tactical-grade inertial sensors with Iridium’s LEO satellite capabilities.

Despite defense dominating current demand, Williams emphasized that commercial applications remain important. “Right now our main market obviously is the defense space and things of that nature,” he said. “But our IMUs are industrial grade up to tactical grade, so there is a portfolio, or a space in the portfolio for your commercial base use cases.”

He pointed specifically to the company’s LiDAR payload business. “That payload is called RESEPI and is used primarily in the commercial space, meaning farming, construction, things of that nature,” Williams said. Whatever the application, whether it’s about supporting battlefield autonomy, or infrastructure mapping and precision agriculture, the underlying requirement remains the same: reliable motion sensing and navigation in challenging environments.

Eurosatory 2026 showed clearly what our readers already knew – assured PNT is now a necessity rather than a specialized capability. Listening to Williams, a consistent case emerged: the future of navigation will not depend on a single sensor, signal or satellite constellation, but will require the ability to combine and interweave the widest available selection of them.

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SparkPNT’s initial lineup includes four product families. Facet FP is an IP67-rated modular GNSS receiver line available in seven configurations, built for serviceability and long-term upgradeability. TX2 is a quadband GNSS receiver supporting RTK and Galileo HAS for centimeter-level positioning, aimed at surveying applications, with an IP67 enclosure and integrated antenna. The SXM-E Reference Station is a continuously operating reference station with a web-based control interface capable of acting as an NTRIP caster. SXT and SXT-D GNSSDO units are timing products designed to deliver sub-1ns accuracy with enhanced frequency stability.

The company is positioning the line around open-source and customizable architecture rather than the proprietary ecosystems that have historically dominated high-precision positioning and surveying.

“For over twenty years, SparkFun has made cutting-edge electronics more accessible. With SparkPNT, we are applying that exact same philosophy to precision positioning,” said Glenn Samala, CEO of SparkFun Electronics. “We aren’t just launching a new line of GNSS products, we are launching an adaptable, future-proof PNT platform that gives industrial, logistics, robotic, and agricultural sectors commercial-grade precision at a fraction of standard costs—fully backed by a mature manufacturing powerhouse that knows how to deliver at scale.”

SparkPNT founder Nathan Seidle said the company’s goal is to open up a market segment built on closed systems. “For decades, the high-precision positioning and surveying markets have been dominated by proprietary ecosystems. Our goal is to provide field-ready high-precision systems that utilize an open-source and customizable architecture, putting true ownership in the hands of the user.”

SparkPNT is based in Boulder, Colorado.

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According to a Telegram post by Ukrainian Defense Ministry advisor Serhii “Flash” Beskrestnov on June 16, Guarantor was developed by the company Rossiysky Kupol LLC based in Simferopol, Crimea and first appeared in 2024 near Kharkiv—where at least one system was destroyed.

But recently in 2026, Russia began multiplying Guarantor deployment along the southern highway “land bridge” between Russian soil and Crimea to counter Ukraine’s destructive medium-range strike drones that have ravaged fuel truck logistics, causing a stark fuel shortage in Crimea.

In response, Ukraine’s military has released videos showing two strikes on individual trailers of Guarantor systems by the 422nd “Luftwaffe” Unmanned Systems Regiment—attached to the 17th Corps operating in central-southern Ukraine.

Beskrestnov describes an approach intended to interfere with a Starlink satellite’s reception of terminal uplinks by transmitting interference in the relevant Ku-band uplink channels:

“Technically, a Starlink satellite receives signals from terminals in the 14–14.5 GHz range. This range is divided into 8 channels, each 62.5 MHz wide. The Russians basically took 8 satellite dishes, pointed them at the satellite, and each dish transmits interference on its own channel.” Beskrestnov claims this can effectively “deafen” the satellite to terminals in the affected area.

He further details that each Guarantor system encompasses six trailers, each with capacity for two of the system’s eight rotating dish antennas, each of which is covered by egg-shaped domes. Implicitly, then, some trailers carry just one antenna. The antennas can be optionally dismounted, and the power-hungry system can either be sustained by trailer-mounted generators or from external sources.

Beskrestnov concludes each system can effectively deny Starlink access across “roughly 20 square kilometers.” Calculating backwards, this implies a circular radius of just over 2.52 kilometers, or 1.57 miles.

That suggests point defense of a local area, but the radius remains small enough that a Starlink-controlled drone with automatic target tracking could still acquire an optical lock from outside this defensive bubble on targets within the protected area, including Guarantor systems themselves. Indeed, optical lock-on seems possibly present in at least one of the videos released by the 422nd Regiment.

Russian Telegram drone blogger “Unmanned Brotherhood” claims Guarantor is causing Ukrainian forces to complain of “significant problems” but concedes the system has downsides: “the EW system is currently quite large and conspicuous, though this issue is expected to be rectified in the future.” Another Russian technical specialist, Sergei Trukhachev, told Russia’s TASS news agency that the system demonstrated “high effectiveness during local tactical operations.”

Beskrestnov claims the systems are being sold at the “absolutely magical” price of $1.5 million apiece. While that does not seem prohibitive by American standards, in consideration of the limited area protected, that price point may prevent deployment from being scaled to extend coverage over large areas like the hundreds of miles of highway in southern Ukraine under assault by Starlink-enabled drones.

That Ukraine itself is striking Guarantor systems suggests they are effective enough to be worth attacking, but nonetheless apparently vulnerable to strikes. Besides being targetable at distance with electro-optical guidance, the system’s high-power emissions could also make it vulnerable to emitter-location tactics, including electronic support measures, loitering munitions cued by RF detection, or purpose-built home-on-jam weapons.

Jamming a cloud of gnats

Starlink is notoriously difficult to jam compared to traditional geostationary satellites, for the same reason it is harder to swat a cloud of gnats than an individual fly: it consists of a network of over 10,000 low-Earth orbit satellites that are constantly moving at high speed. Although each satellite remains overhead for roughly five to seven minutes, Starlink’s network timing and beam/satellite management operate on short, synchronized intervals, and user terminals can transition among satellites as geometry changes, complicating attempts to focus jamming on a single moving spacecraft.

This means that a huge number of emitters would be needed to continuously jam Starlink over a wide area; for example, a study by China’s Zhejiang University and Beijing Institute of Technology estimated China would require at least 935 high-powered, or 2,000 low-powered, aerial jamming platforms to deny Starlink across an area the size of Taiwan, or 13,900 square miles.

With its focus on just one satellite at a time, it is not clear how well Russia’s Guarantor overcomes the Starlink “cloud of gnats” challenge. Is an external system continuously re-cueing the Guarantor jammers to target the next most relevant satellite as their orbital positions shift? And if Guarantor only jams one satellite at a time, does that really suffice to ensure another Starlink satellite is not also able to cover that area simultaneously?

It is also worth bearing in mind that Starlink’s jamming resistance extends beyond distributed targeting to other design characteristics, including the ability to adaptively null interference returns from areas generating jamming signals.

Intel on Rossiysky Kupol LLC

A Russian article in March 2025 provides additional details on a C-UAS “super EW” system developed by approximately 150 scientists at Rossiysky Kupol LLC, funded in part by local authorities in Crimea, and allegedly effective against UAS targets at a 20-kilometer radius, or 12.4 miles. Without otherwise mentioning satellite jamming, the article alleges this system “unintentionally suppressed” GPS signals in a neighboring European country, presumably Romania, and allegedly “prevented” an attack by 25 drones targeting a plant near Rostov.

The rise of satellite mega-constellations

It is instructive to observe Russia’s efforts to defend against a distributed satellite mega-constellation, because this technology is not destined to remain uniquely in American hands.

Russia itself is spending approximately $5.3 billion attempting to build a constellation of 292 satellites by 2030 called Rassvet, or “Dawn,” with plans to further scale to 900 satellites. Progress to date has been slow, with 16 operational satellites launched from Plesetsk, one of which has since failed.

Meanwhile, China is advancing three mega-constellations: the commercially oriented Qianfan, or “Thousand Sails,” aiming for 15,000 satellites; the state-owned GuoWang, or “National Network,” a dual-use constellation with 13,000 satellites; and the telecom-oriented Honghu-3, aiming for 10,000 satellites.

Implications for LEO constellation resilience

Guarantor is clearly no panacea. It cannot broadly overcome the distributed redundancy of the Starlink mega-constellation—a single system covering 20 square kilometers against a network of more than 10,000 satellites performing rapid handoffs is, at best, a pinhole defense. Yet the ability to shield a limited, high-value area can still be meaningfully preferable to having no defense at all, and Russian commanders appear to have drawn that same conclusion.

The more consequential lesson is strategic. Russia, China, and the United States all possess broader, not fully disclosed counterspace capabilities, but those tools are rarely available to tactical field commanders. What Guarantor represents is an attempt to bring satellite denial to the unit level—trading coverage breadth for deployability. As LEO mega-constellations multiply and become the backbone of battlefield communications for multiple powers, the tactical demand for localized counter-constellation tools will only grow. The U.S. and its allies, potentially facing adversary LEO networks of comparable scale within a decade, would be prudent to treat Guarantor not as a curiosity but as an early indicator of a new category of tactical electronic warfare.

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SkyBarrier is designed to jam all four major global navigation satellite systems simultaneously: GPS, GLONASS, Galileo, and BeiDou. HENSOLDT states the jamming effect covers both civilian and military signal variants, including encrypted signals, across the full range of currently relevant frequency and coding variants.

The system is built around rapid deployment: HENSOLDT says two operators can complete setup — including mast assembly and cabling — within minutes, with activation via a mechanical front-panel switch requiring no software configuration. The complete system consists of a single portable electronics unit, an extendable telescopic mast, and associated accessories.

HENSOLDT designed SkyBarrier for incremental upgradability, stating that new signal types can be added by replacing individual components rather than the full system. The company also notes a minimal physical interface profile — three hardware interfaces with no external data communication pathways — as a deliberate cybersecurity measure.

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PANOSETI — Pulsed All-sky Near-infrared Optical SETI — is a multi-institutional program led by researchers at the University of California, Berkeley. The system requires extremely precise time coordination across widely separated telescope nodes to detect fast-transient optical and near-infrared signals. Traditionally that level of synchronization has depended on fiber-based infrastructure such as White Rabbit, which is costly and impractical to deploy at remote observatory sites.

Using the u-blox ZED-F9T, the PANOSETI team demonstrated approximately 0.7 nanosecond standard deviation between 1PPS signals over a 1-kilometer baseline, with performance improving to around 200 picoseconds using filtering techniques — meeting or exceeding the requirements for next-generation distributed sensing systems.

“Achieving this level of synchronization without fiber is a significant step forward for distributed instrumentation,” said Dan Werthimer, Chief Scientist of the PANOSETI project at UC Berkeley. “It allows us to achieve the timing precision we need for our telescope array in locations where traditional fiber-based systems are not feasible.”

The u-blox announcement frames the result as extending beyond scientific research, pointing to applications in distributed sensor networks, remote timing systems, and resilience of critical infrastructure.

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The milestone centers on Qualinx’s QLX3xx — a reconfigurable GNSS SoC and Analog Front End targeting secure positioning, navigation, and timing applications, including resilient timing and synchronization networks and ultra-low-power GNSS receivers for connected edge deployments. The chip was designed, taped out, and manufactured entirely at GF’s Dresden fab using its FDX process technology. No design data or physical materials left the European Union at any stage of production.

“Our partnership with Qualinx marks the first operational milestone,” said Dr. Manfred Horstmann, SVP and General Manager at GF. “It shows that complex, security-relevant ASIC designs for aerospace, defense, and critical infrastructure can already be industrialized today using a fully European, trusted manufacturing path.”

Qualinx CEO Tom Trill characterized the flow as proof that full European manufacturing control is no longer theoretical. “This first secure product demonstrates that a fully European manufacturing path — from mask services to wafer production — is already a reality today,” he said, adding that the effort gives Qualinx complete control over IP, data, and supply chain within Europe.

The Dresden fab’s sovereign manufacturing capability is co-funded under the European Chips Act. GF says it aims to have a fully automated trusted European flow in place by end of 2026, with regular foundry engagements available to aerospace and defense customers starting in 2027. That roadmap will incorporate European IP partners, mask houses, and OSAT service providers.

GF is also working with Deutsche Telekom on a parallel effort to ensure that production data — from design and tape-out through manufacturing and quality — can be processed, transported, and stored entirely on European networks, cloud infrastructure, and data centers. The practices developed there are intended to feed directly into the scaling of the sovereign manufacturing model.

Qualinx, headquartered in Delft, Netherlands, was founded in 2015. The company’s proprietary Digital Radio Frequency technology implements traditional analog receive-chain functions in digital hardware, targeting GNSS, PNT, and PVT chipsets and modules for applications ranging from automotive and fleet to wearables and asset tracking.

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Murata had previously invested in Xona through WONDERSTONE Ventures, its corporate venture capital arm. The MOU moves the relationship downstream toward hardware, pairing Murata’s capabilities in high-frequency communications, sensors, timing devices and module design with Xona’s LEO-based PNT infrastructure.

Xona’s Pulsar service is built on a dedicated LEO constellation designed to deliver significantly stronger signals than conventional GNSS, with centimeter-level positioning accuracy, faster convergence times, reduced multipath error and improved performance in urban and indoor environments. Pulsar is designed for GNSS compatibility, enabling integration with existing user equipment as a complement rather than a replacement.

The two companies identified data centers and financial institutions requiring precise timing synchronization for 5G and 6G communications infrastructure, and off-road construction and agricultural machinery operating in environments where GNSS availability is limited, as near-term application targets.

Murata described the space domain as a new growth area, framing the partnership as part of a broader commitment to advancing positioning and timing synchronization as foundational technology across communications infrastructure, industrial equipment, mobility and consumer IoT. The company’s scale — it is among the world’s largest manufacturers of passive electronic components — gives the partnership potential reach across global industrial supply chains that few LEO PNT agreements to date have carried.

The announcement follows Xona’s appearance in GPS Innovation Alliance testimony before the House Energy and Commerce Subcommittee on Communications and Technology last week, where GPSIA executive director Lisa Dyer cited six Xona satellite launches planned for this fall and called on Congress to urge FCC approval of the company’s pending radionavigation-satellite service license application.

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What emerged was a detailed picture of a system that remains the world’s gold standard for civil and military PNT—operationally reliable, economically indispensable—but one whose modernization has fallen behind the pace of threat, and whose complement architecture is now the subject of a spectrum dispute with consequences well beyond the PNT community.

This account is based on the written statements submitted to the subcommittee by the five witnesses.

The five witnesses were Lisa Dyer, executive director of the GPS Innovation Alliance (GPSIA); Sam Matheny, chief executive of the newly launched Merkhet Solutions; Mariam Sorond, CEO and board chair of NextNav; Harold Feld, senior vice president of Public Knowledge; and J. David Grossman, vice president for policy at the Consumer Technology Association.

The constellation: strong record, narrowing margins

Dyer’s written statement provided the most technically grounded account of GPS’s current status.

The constellation has not experienced a system-wide outage since achieving full operational capability in 1995. The FAA reports GPS system availability at 99.9999 percent. Thirty-two satellites are on orbit, eight above the 24-satellite minimum required for global coverage. The Wide Area Augmentation System extends accuracy and monitors signal integrity across the National Airspace System.

Against that record, Dyer placed a more pressing set of facts. Eight of the 32 satellites are operating on a single string—one subsystem failure each from becoming non-operational. More consequentially, on April 17, 2026, the Space Force terminated the GPS Next Generation Operational Control System program, the long-delayed ground-segment effort that had run more than a decade behind schedule and triggered a Nunn-McCurdy cost breach. Dyer framed the cancellation as an overdue clearing of the path for rapid modernization, and for what she described as a more deliberate integration of commercial satellite PNT data into military operations.

She also documented a capability asymmetry that the subcommittee has not previously examined at this level of specificity. GPS III satellites deliver eight times the anti-jamming protection for military users over their predecessors. GPS IIIF satellites, when fielded, will deliver 63 times. Neither generation extends those protections to civil, commercial or scientific signals. Dyer argued the civil-signal gap carries national security implications precisely because aviation, maritime and surface transportation operators—sectors that depend on civil GPS signals—provide mission-critical logistical support to the Defense Department.

GPSIA submitted formal recommendations on GPS modernization to the defense subcommittees of both Appropriations Committees and both Armed Services Committees the week of the hearing. In September 2025, the Alliance sent a letter to Secretaries Hegseth and Duffy outlining a range of whole-of-government options for addressing jamming and spoofing.

Interference: from conflict zone to domestic runway

Witnesses presented interference as a problem that has moved decisively from theoretical to operational. Sorond cited two 2022 incidents on U.S. soil: a jamming event of unknown origin that shut down a runway at Dallas–Fort Worth International Airport and disrupted roughly 40 miles of airspace for nearly two days, and a separate unauthorized transmitter that interfered with GPS operations at Denver International Airport, affecting both aircraft and air traffic control. Feld’s written statement pointed to a more recent example: Russia’s jamming of the GPS systems aboard the RAF aircraft carrying UK Defense Minister John Healey as he returned from a visit to Estonia. Dyer referenced third-party data aggregating more than 55,000 reported GPS interference events in commercial aviation in 2025—a 24 percent increase over 2024—noting that while the majority occurred overseas and near active conflict zones, a portion occurred within U.S. airspace or on approaches to U.S. destinations.

Dyer was pointed on enforcement. The legal framework is not the problem—federal law already prohibits the manufacture, sale and operation of jamming equipment that interferes with authorized radio communications. In her written statement, she argued that the FCC and the Department of Transportation lack the budget and personnel to enforce those laws, coordinate a whole-of-government response, or adequately address the growing volume of incidents. She called on Congress to provide both agencies with the resources to meet their existing mandates.

The complement landscape: consensus on need, but not on method

Where the panel converged on the modernization and interference questions, it divided sharply on the path to a resilient complementary architecture.

Matheny testified on behalf of Merkhet Solutions, an independent company launched June 2 to commercialize the Broadcast Positioning System (BPS), a terrestrial PNT technology developed at the National Association of Broadcasters starting in 2021. BPS embeds timing and tower-location data within ATSC 3.0 transmission signals. A single tower provides traceable time; multiple towers enable positioning by the same multilateration geometry as GPS. The system requires no internet, satellite or cellular connectivity, operates on existing licensed broadcast spectrum, and supports passive, unlimited simultaneous reception.

Matheny cited a 2025 peer-reviewed NIST finding—produced under a 2024 cooperative research and development agreement—that BPS time-transfer performance is “comparable to or better than GNSS” and constitutes a “viable complementary PNT solution.” A Department of Transportation field trial with Dominion Energy, contracted in August 2025, is underway at a major East Coast substation, assessing BPS performance for grid timing applications. Merkhet currently has deployments in Washington, D.C., Baltimore and Denver. ATSC 3.0 is live in 80 markets reaching more than 75 percent of the U.S. population.

NextNav’s position was presented by Sorond. The company’s Pinnacle vertical-location service is operational in more than 4,400 cities, serves more than 90 percent of U.S. commercial buildings taller than three stories, and provides commercial Z-axis with deployments on all three national wireless carriers and FirstNet. NextNav holds more than 150 patents and describes itself as the largest license holder in the only band the FCC has designated for ground-based positioning.

The company has a petition pending before the FCC that it characterizes as a modernization of its existing licenses in the 902–928 MHz band, to support what it describes as a 5G-based horizontal PNT complement and backup to GPS, deployable on existing wireless infrastructure at no direct cost to taxpayers. The band supports a wide range of licensed and unlicensed operations — among them electronic toll collection systems such as E-ZPass, utility smart meters, home security alarms, agricultural sensors, RFID inventory systems and medical alert devices — that collectively represent decades of investment built on the FCC’s existing coexistence framework.

On the question of modernization, Feld argued that the petition does not update existing rules but asks the FCC to eliminate them—specifically, the protective conditions the Commission attached to the M-LMS licenses when it created them in 1995. That order explicitly acknowledged that Part 15 unlicensed devices had “developed and proliferated in this band and are providing services that are valuable and in the public interest,” and conditioned the new licenses on field testing to demonstrate no unacceptable interference. Feld wrote that NextNav has since “consistently requested that the FCC eliminate the rules protecting unlicensed operations in the band” rather than pursue the cooperative coexistence the 1995 order envisioned.

On the cost question, Feld wrote that the proposed transaction would exchange roughly 14 MHz of shared, low-power spectrum with a partial national footprint for 15 MHz of full-power, flexible-use national spectrum—rights that would be worth billions of dollars if acquired at auction. Feld wrote that, based on the company’s filings, PNT would occupy a small fraction of the resulting network capacity, with the remainder available for mobile carrier use. On the question of deployability, Feld wrote that the proposal would require development of new chips and new 5G standards before any commercial deployment—a process that would take years and depends on wireless carrier adoption that has not been secured.

Grossman characterized the proposal as a structural reconfiguration of the band’s operating environment, not a marginal technical adjustment, and argued that the record of innovation built on existing rules must be weighed against claims of future benefit.

The LEO tier: commercial systems advancing without Washington

Running through the hearing but never its explicit focus was the accumulating progress in commercial low Earth orbit PNT—the tier that may ultimately prove most consequential for complementary architecture.

Dyer described three U.S. companies in various stages of deployment. Iridium operates the first commercial LEO PNT system in the United States, with more than 70 partners across 25 states. TrustPoint is developing a C-band constellation designed for orbital, signal and frequency diversity relative to L-band GPS; three satellites are on orbit, four more in development, with commercial service targeted for 2027. Xona is broadcasting a new signal designed for compatibility with existing GPS receiver infrastructure, scaling manufacturing in California with six launches planned this fall. GPSIA formally recommended that Congress urge FCC approval of Xona’s pending radionavigation-satellite service license application (ICFS File No. SAT-LOA-2023-0711-00165).

Feld anchored the panel’s broader policy argument in the GPS-as-public-good framing, warning against any architecture evolution that would introduce tiered access, impose new costs on agricultural and rural users who rely on free GPS today, or allow the existing system to degrade in favor of proprietary alternatives. He called for privacy-by-design principles to be incorporated into next-generation PNT at the system level rather than addressed through post-hoc regulation.

The record as it stands

The hearing did not resolve the FCC proceedings it illuminated. Its contribution was to put the state of the U.S. PNT posture on the legislative record at a moment when three distinct tracks—GPS modernization, interference enforcement and complement architecture—are simultaneously in motion, each with its own pending proceedings and its own constituency of stakeholders whose written positions now form part of the official record.

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