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  • Greenland is twisting and stretching, GNSS data shows

    Greenland is twisting and stretching, GNSS data shows

    Greenland is being twisted, compressed and stretched, according to researchers in the Department of Space Research and Space Technology of the Technical University of Denmark (DTU Space). As a result, the entire island has shifted northwest over the past 20 years by about 2 centimeters per year.

    GNSS data shows plate tectonics and movements in the bedrock caused by the melting of large ice sheets, reducing pressure on the subsurface. The pressure is easing both because large amounts of ice have melted in Greenland in recent years, and because the bedrock is still affected by the enormous ice masses that have melted since the peak of the last Ice Age around 20,000 years ago.

    Horizontal land motion observed by the 58 GNET stations used in this study, processed in the IGS14 reference frame. Their location is shown by the colored circles together with their labels. The boundaries of Greenland's drainage basins are shown in green with numbers (1) to (7b). The Greenland Ice Sheet (GrIS) is represented in white and peripheral glaciers in Greenland (GrPG) and Arctic Canada (CanPG) are highlighted in black and purple respectively. (Image: Study authors)
    Horizontal land motion observed by the 58 GNET stations used in this study, processed in the IGS14 reference frame. Their location is shown by the colored circles together with their labels. The boundaries of Greenland’s drainage basins are shown in green with numbers (1) to (7b). The Greenland Ice Sheet (GrIS) is represented in white and peripheral glaciers in Greenland (GrPG) and Arctic Canada (CanPG) are highlighted in black and purple respectively. (Image: Study authors)

    The new measurements are based on 58 GNSS stations placed around Greenland. They measure Greenland’s overall position, elevation changes in the bedrock, and how the island is shrinking and stretching. The movements are causing Greenland to both expand and contract horizontally. The effect is that Greenland’s area is currently being “stretched out” and becoming slightly larger in some regions, while others are being “pulled together.”

    ”Overall, this means Greenland is becoming slightly smaller, but that could change in the future with the accelerating melt we’re seeing now,” said DTU Space postdoc researcher Danjal Longfors Berg, lead author of the article in the Journal of Geophysical Research.

    It is the first time the horizontal movements have been described in such detail.

    ”We have created a model that shows movements over a very long timescale from about 26,000 years ago to the present. At the same time, we have used very precise measurements from the past 20 years, which we use to analyze the current movements. This means we can now measure the movements very accurately,” Berg said.

    Important for surveying and navigation

    The new research provides useful information about what happens when climate change hits the Arctic with accelerating speed, as is the case in these years.

    ”It’s important to understand the movements of landmasses. They are of course interesting for geoscience. But they are also crucial for surveying and navigation, since even the fixed reference points in Greenland are slowly shifting,” Berg said.

    The GNSS stations are owned by the Climate Data Authority under the Ministry of Climate, Energy and Utilities. They are used for research purposes and operated in collaboration with DTU Space. The research is conducted under the DTU Space research center Center for Ice-Sheet and Sea-Level Predictions (CISP).

  • Adaptive model shields real-time positioning from ionospheric chaos

    Adaptive model shields real-time positioning from ionospheric chaos

    For users relying on centimeter-level accuracy — such as surveyors, engineers and autonomous systems — ionospheric disturbances can mean system downtime and significant losses. Traditional network real-time kinematic (NRTK) positioning methods assume smooth ionospheric conditions and thus fail during active solar periods.

    To meet these challenges, a research team from Wuhan University and Guangzhou Hi-Target Navigation Tech Co. Ltd. developed an NRTK positioning model capable of maintaining centimeter-level accuracy under intense ionospheric disturbances.

    This approach could serve as the foundation for next-generation, self-correcting navigation systems that operate reliably under any atmospheric condition.

    The study (DOI: 10.1186/s43020-025-00179-4), published in Satellite Navigation on Oct. 6, introduces a dual-optimization framework that integrates real-time ionospheric indices with adaptive functional and stochastic models. By learning from disturbance patterns and automatically recalibrating user-side algorithms, the system dramatically enhances GNSS reliability during the ongoing solar cycle peak — offering a key safeguard for positioning technologies in low-latitude regions most vulnerable to ionospheric turbulence.

    The innovation centers on leveraging the rate of the total electron content index (ROTI), a key indicator of ionospheric activity, to dynamically adjust both ionospheric residual estimation and observation weighting. When the system detects disturbances, it automatically reduces the influence of affected satellites and refines error models in real time.

    Using data from Hong Kong’s Continuously Operating Reference Station (CORS) network — one of Asia’s most active low-latitude regions — the researchers found that ROTI showed a strong positive correlation (0.91) with ionospheric interpolation errors and a negative correlation (–0.9) with signal-fixing rates.

    Compared to conventional NRTK methods, their adaptive “Method B” improved horizontal and vertical positioning accuracy by 37.6% and 41.6%, respectively. Moreover, it achieved a stable 84% average fixing rate, even during equinoctial months when ionospheric scintillation is strongest. The results reveal not just a technical upgrade but a practical solution for real-time navigation across regions frequently affected by solar-induced ionospheric noise.

    “Our method essentially teaches GNSS systems to think smarter under stress,” said Xiaodong Ren, senior researcher at Wuhan University and lead author of the study. “By allowing the model to ‘sense’ and adapt to space-weather disturbances in real time, we’ve moved beyond static correction systems toward intelligent positioning. This is crucial not only for maintaining accuracy but also for ensuring resilience as solar activity intensifies.”

    He added that this approach could serve as the foundation for next-generation, self-correcting navigation systems that operate reliably under any atmospheric condition.

    This adaptive NRTK framework marks a significant leap forward for industries that depend on precise, real-time location data — from autonomous driving and drone surveying to precision agriculture and infrastructure monitoring, Ren said. By integrating live ionospheric monitoring into everyday positioning workflows, it ensures continuous accuracy even when solar storms strike.

    Future developments may combine the model with artificial intelligence and multi-constellation GNSS networks to further enhance forecasting and resilience. As Earth moves through one of its most active solar cycles, Ren said, such innovations will be essential to keeping navigation, communication and automation systems firmly on course.

  • U-blox launches firmware-upgradeable GNSS chips with low power consumption

    U-blox launches firmware-upgradeable GNSS chips with low power consumption

    U-blox has launched the UBX-M10150-KB chip and the MAX-M10N module, the first M10-platform GNSS hardware designed with firmware upgradeability. Both products run the new SPG 5.30 firmware, introducing Low Energy Accurate Positioning (LEAP) — a mode that reduces power consumption by up to 50 percent while maintaining superior positioning accuracy.

    Designed for battery-powered devices, the new chip offers ultra-low power consumption of just 8 mW in continuous tracking. The new products are suitable for vehicle, people and pet tracking, as well as livestock monitoring and wearable applications.

    The UBX-M10150-KB and MAX-M10N extend the capabilities of the M10 family beyond previous ROM-based products. With SPG 5.30, they offer a set of new technical features: LEAP replaces cyclic tracking mode to achieve significant energy savings including external LNA power cycling, and RTCM corrections input supports positioning accuracy down to the sub-meter level. In addition, the firmware adds data logging and geofencing functions, enabling more autonomous tracking and monitoring directly on the device.

    By combining these improvements with firmware upgradeability, the new hardware provides a future-proof solution. Customers can benefit from future firmware releases that deliver ongoing performance enhancements and new functionality throughout the product lifecycle, the company said.

    Both products include lifetime access to AssistNow Predictive Orbits and Live Orbits, which accelerate start-up times and improve positioning performance when using small antennas or operating in weak-signal environments. The EVK-M102 evaluation kit and u-center 2 software are available to simplify the design-in phase for developers.

    The UBX-M10150-KB and MAX-M10N, running SPG 5.30 firmware, are available as engineering samples now and will be fully available later in this month.

  • RIN conducts survey on maritime GNSS interference

    RIN conducts survey on maritime GNSS interference

    The Royal Institute of Navigation (RIN) Maritime Working Group is investigating GNSS jamming and spoofing in the maritime sector, starting with a survey. The survey is “aimed at anyone in the maritime sector who has experienced GNSS interference and who can provide us with further information on the impact that it is having,” the group stated.

    Interference have been pervasive for years now in areas such as the Baltic Sea and the Black Sea. In the Strait of Hormuz alone, almost 1,000 ships per day experience GNSS interference, impacting crew safety and the security of their cargo. Collisions and groundings are a very real threat, with the Frontier Eagle and MSC Antonia accidents being the most recent examples.

    The RIN will be producing a report similar to the September 2024 OPSGROUP report that focused on GPS spoofing in the aviation sector.

    The survey is available on the RIN website.

  • Emlid launches GNSS receiver line to simplify precision positioning

    Emlid launches GNSS receiver line to simplify precision positioning

    Emlid has introduced a new generation of all-band RTK receivers including the Reach RX2, Reach RS4 and Reach RS4 Pro. They are built for surveyors, GIS specialists and construction teams seeking reliable, high-accuracy positioning with consumer-level ease of use. This EU-based developer of high-precision GNSS receivers and software is on a mission to make professional-grade precision simple, fast and scalable.

    The Reach RS4 and RS4 Pro mark a significant step forward from previous Emlid models, combining rugged engineering with faster workflows and uncompromised accuracy. The flagship Reach RS4 Pro introduces innovative camera-vision technology that blends traditional RTK with visual positioning to cut survey time and simplify work in complex environments.

    Image: Emlid
    Image: Emlid

    Both receivers support all-band RTK reception (L1/L2/L5/L6) across every major satellite constellation, ensuring consistent performance even under canopy or in urban canyons. An integrated antenna system with diversity LTE, dual-band Wi-Fi and Bluetooth provides a clean GNSS signal and stable fix, while the Emlid multi-band radio system — up to 2W and interoperable with third-party gear — offers flexible correction transmission at 450MHz and 915MHz for both licensed and licence-free use.

    Further enhancements include next-generation IMU tilt compensation that initializes up to five times faster than before, a durable magnesium alloy body with IP68 protection, and Made for iPhone certification enabling smooth integration with iOS applications such as Esri ArcGIS. A new quick-release survey pole mount ensures fast and accurate setups, even when tilted.

    AR-based stakeout and measurement from images. Building on the RS4 platform, the RS4 Pro adds dual factory-calibrated full-HD cameras that enable augmented reality (AR) stakeout and measurement from images. The AR interface projects geometries directly in the Emlid Flow app, guiding users intuitively to stakeout points. The image-based measurement feature allows for accurate coordinate capture from photos, which is ideal for hard-to-reach places such as facades or active roadways. Together, these vision-based tools streamline fieldwork and reduce reliance on total stations in difficult conditions.

    For users prioritizing mobility, the Reach RX2 delivers professional RTK performance in a compact, plug-and-play format. Like its larger counterparts, it supports all-band RTK signals and features a second-generation IMU tilt compensation system for level-free measurements. A new quick-release mount enables rapid setup in the field.

    Designed for GIS, construction and asset management teams managing multiple projects, the Reach RX2 integrates seamlessly with Esri ArcGIS for data collection and Pix4Dcatch for mobile terrestrial scanning.

    Complete field-to-office workflow. Emlid’s product ecosystem — including the Emlid Flow mobile app and Emlid Flow 360 cloud platform — creates a complete field-to-office workflow for professionals who value simplicity without sacrificing precision. The system enables companies to assign surveying tasks to non-surveyor teams, reducing training requirements while maintaining professional accuracy standards.

  • NextNav moves toward commercializing its 5G cellular PNT solution

    NextNav moves toward commercializing its 5G cellular PNT solution

    NextNav Inc. has successfully advanced its NextGen PNT solution commercialization path operating on standard 5G network equipment. The development represents a major milestone toward a widescale commercial 5G-powered 3D PNT solution. The company is showcasing its solution this week at Mobile World Congress in Las Vegas, booth #96.

    “This latest achievement highlights the seamless integration of NextNav’s technology and 5G, reinforcing the scalability and practicality of a resilient terrestrial complement to GPS,” said Sidd Chenumolu, chief business development officer. “We have proven the technology with standard 5G equipment and look forward to the opportunity to completing the final steps to commercialization.”

    NextNav completed demonstrations using Lekha Wireless Solutions 5G base stations with positioning reference signals (PRS) enabled. The partnership with Lekha Wireless Solutions, a commercial 5G infrastructure equipment supplier, brings PNT capabilities in the NextNav spectrum band.

    The demonstration delivered accurate timing and positioning information via PRS transmissions while simultaneously delivering both downlink and uplink data transmissions. These capabilities align tightly with NextNav’s broader solution of utilizing standards-based 5G PRS in lower 900 MHz band spectrum for terrestrial PNT and combining it with barometric pressure sensors for vertical accuracy.

    “Demonstrating these capabilities on commercial 5G equipment is a critical step towards integrating this solution into networks, a hallmark of NextNav’s 3D PNT architecture,” said NextNav Co-Founder and CTO Arun Raghupathy. “It shows that our PNT solution can be deployed efficiently using existing 5G equipment, delivering accurate timing and positioning information along with simultaneous 5G data.”

    At MWC Las Vegas, NextNav will showcase these developments as well as an interactive demonstration of the company’s Pinnacle technology, highlighting how vertical location transforms government, public safety, and commercial applications.

  • Savvy Navvy charts integrated into CPAC Systems’ new product line

    Savvy Navvy charts integrated into CPAC Systems’ new product line

    Marine technology company Savvy Navvy will provide its chart solution to CPAC Systems for integration into CPAC’s Marivue product line, the companies announced.

    The Marivue product line offers infotainment, connectivity and display technology for recreational vehicles and marine applications, including pontoons and watersports vessels.

    “Integrating Savvy Navvy into the Marivue product line strengthens our ecosystem with a proven, user-focused navigation solution,” said Håkan Stigeberg, director of marine segment at CPAC Systems.

    Jelte Liebrand, CEO and founder of Savvy Navvy, said the integration aims to modernize chartplotters through cutting-edge technology. The system allows users to plan routes on their phones and transfer them to onboard displays.

    Savvy Navvy has recorded more than 3 million downloads globally. The application provides routing based on real-time data including departure time, chart information, weather conditions, tides, boat specifications and local regulations.

    The company launched Savvy Integrated less than 12 months ago to integrate its charts and features into built-in boat management systems.

  • SkyWire from Microchip makes it easier to compare clocks across locations

    SkyWire from Microchip makes it easier to compare clocks across locations

    Microchip Technology’s new SkyWire is a time measurement tool embedded in its BlueSky Firewall 2200. It’s designed to measure, align and verify time to within nanoseconds even when clocks are long distances apart. The technology enables highly scalable and precise time traceability to metrology labs to protect critical infrastructure systems.

    Network clocks are the backbone of critical infrastructure operations, with the precise alignment of clocks becoming increasingly important for data centers, power utilities, wireless and wireline networks and financial institutions.

    For critical infrastructure operators to deploy timing architectures with reliability and resiliency, their clocks and timing references must be measured and verified to an authoritative time source such as Coordinated Universal Time (UTC).

    With the BlueSky GNSS Firewall 2200 and SkyWire technology, geographically dispersed timing systems can be compared to each other and compared to the time scale systems deployed at metrology labs within nanoseconds. Measurement of clock alignment and traceability to this level has typically only been done between metrology labs and scientific institutes.

    With Microchip’s solution, critical timing networks for air traffic control, transportation, public utilities and financial services can achieve alignment within nanoseconds between its clocks to protect their infrastructure no matter where the clocks are located.

    “To ensure timing systems are delivering to stringent accuracy requirements, it’s important to measure and verify in an independent manner relative to UTC as managed by national laboratories and traceable to the Bureau International Poids et Mesures (BIPM),” said Randy Brudzinski, corporate vice president of Microchip’s frequency and timing systems business unit. “With the new SkyWire technology solution, we’re making UTC more widely accessible so that large deployments of clocks can be independently measured and verified against each other across long distances.”

    The concept originated as an extension to the National Institute of Standards and Technology’s (NIST’s) pre-existing service called Time Measurement and Analysis Service (TMAS), which is utilized by entities that are required to maintain an accurate local time standard. The BlueSky GNSS Firewall 2200 with SkyWire technology provides a commercial off-the-shelf (COTS) product to enable critical infrastructure operators to connect with the NIST TMAS Data Service for large-volume clock deployments.

    “At NIST, our goal is to enable the most accurate time to support our country’s infrastructure,” said, Andrew Novick, NIST engineer. “Our TMAS Data Service, in conjunction with commercial hardware, provides a scalable solution for anyone who needs traceable and accurate timing.” 

    Nations around the globe can replicate this solution using Microchip’s SkyWire technology capabilities within its TimePictra software suite, which delivers similar features and functionality as that provided by the NIST TMAS Data Service. Metrology labs, government agencies and enterprises worldwide can deploy TimePictra software suite and the BlueSky GNSS Firewall 2200 with SkyWire technology and have their own end-to-end solution for traceable time measurement, alignment and verification. 

    The TimePictra software suite provides customers with support to deploy BlueSky GNSS Firewalls at scale.

  • ProStar and Bad Elf team up on global mapping tech

    ProStar and Bad Elf team up on global mapping tech

    ProStar’s PointMan software will now be bundled with Bad Elf’s high-precision GNSS receivers for worldwide sales. PointMan Precision Mapping provides a powerful cloud and mobile precision mapping solution to surveyors and geospatial intelligence systems (GIS) professionals.

    This strategic partnership expands the market reach of both companies and directly addresses the growing demand for a complete mapping solution in the utility and critical infrastructure industries.

    By combining Bad Elf’s advanced GNSS receivers with ProStar’s patented precision mapping solution, utility owners, contractors, municipalities and engineering firms are able to capture, record and visualize the precise location of critical infrastructure at a low cost and with a complete solution.

    Bad Elf delivers accurate, compact, lightweight and cost-effective GNSS solutions compatible with a broad range of third-party vendors. Together with PointMan, the bundled solution provides customers with a comprehensive, ready-to-deploy precision mapping solution designed to reduce costs, improve efficiency and accelerate industry adoption.

  • Royal Navy trials quantum navigation systems with University of Sussex

    Royal Navy trials quantum navigation systems with University of Sussex

    The UK Royal Navy‘s Disruptive Capabilities and Technologies Office (DCTO) recently teamed up with scientists from the University of Sussex to test new navigation sensors developed to reduce reliance on GPS navigation.

    The ultra-sensitive quantum sensors measure tiny variations in the Earth’s magnetic field, offering a new way to pinpoint locations when satellite signals are jammed or unavailable.

    “We are excited and pleased to have supported this first sea trial with the University of Sussex and its quantum magnetometer technology,” said Commander Matt Steele, from DCTO. “We are also grateful to our colleagues in the Hydrographic Exploitation Group for providing one of its vessels and crew to provide a test platform.

    “To ensure it can resiliently operate in GNSS-denied and degraded environments, the Royal Navy continues to explore and accelerate the development of alternative means of navigation, such as this magnetic sensor, while positioning itself as a pioneer ‘quantum-enhanced navy’.”

    “GPS or GNSS signals are highly vulnerable to disruption: they can be jammed or spoofed, and they fail entirely underground, underwater, or in heavily obstructed environments,” said Tom Coussens, Research Fellow in Quantum Science and Technology at the University of Sussex. “This vulnerability has serious economic and operational consequences. While alternative systems such as inertial navigation and visual recognition exist, none simultaneously meet all critical requirements: long-term positional accuracy, weather independence, and resistance to jamming.”

    In the trials, a team from the university worked with the Royal Navy’s Hydrographic Exploitation Group who survey waters, recording details of depth, seabed objects and composition. The university used its Optically Pumped Magnetometers in open waters, with the trials taking place from His Majesty’s Naval Base Portsmouth.

    In addition to navigation, they also successfully mapped surrounding magnetic signatures, pointing to new methods for detecting vessels, undersea features, and potential hazards.

  • ESA honors Rohde & Schwarz for contributions to satellite navigation over 30 years

    ESA honors Rohde & Schwarz for contributions to satellite navigation over 30 years

    The European Space Agency (ESA) marked 30 years of European satellite navigation with a celebration Sep. 2 at its research and technology center. The event honored key contributors who have shaped the journey of systems like Galileo and EGNOS, which have positioned Europe as a global leader in satellite navigation.

    Among the honorees was Rohde & Schwarz, recognized for the excellence, commitment and long-standing partnership leading to the success of European satellite navigation programs over the past three decades.

    Javier Benedicto kicks off the celebration of 30 years of satellite navigation. (Photo: ESA)
    Javier Benedicto kicks off the celebration of 30 years of satellite navigation. (Photo: ESA)

    The event brought together institutional and industrial partners, ESA Member State representatives, and leading figures in satellite navigation. The celebration revisited pivotal milestones in Europe’s satellite navigation history and looked ahead to future innovations.

    A highlight of the evening was the award ceremony led by ESA Director of Navigation Javier Benedicto, who, alongside past directors, presented accolades to organizations and partners instrumental in this success story.

    Rohde & Schwarz’s recognition underscores their role in advancing European satellite navigation technology. Their contributions have been vital in the development and operational success of Galileo and EGNOS, systems that have revolutionized positioning, navigation, and timing services across Europe and beyond.

    The event not only celebrated past achievements but also set the stage for the future of European satellite navigation, with discussions around upcoming initiatives and advancements. For Rohde & Schwarz and other honourees, the evening served as both a celebration of past achievements and a call to continue building a connected, resilient, and sustainable future in space.

    “Thirty years of satellite navigation is a testament to shared vision, determination to push technology boundaries, and intense, long-term collaboration,” said Rob Short, director of Business Development at Rohde & Schwarz. “We are honoured to have contributed to this remarkable achievement. Congratulations to everyone who made this milestone possible.”

  • Calian GNSS launches advanced antennas for high-precision operations

    Calian GNSS launches advanced antennas for high-precision operations

    Calian GNSS, a leader in high-precision antenna technology, has introduced the Accutenna 4 (AC4) antenna family for increased accuracy, reliability and performance across the full GNSS spectrum.

    Based on a novel stacked composite patch antenna element, the AC4 element combines a robust and compact, full band quad-feed design, in half the weight of current patch antennas on the market. Its highly efficient radiating element and precise phase pattern associated with Calian’s proven eXtended Filtering (XF) technology will deliver clean and accurate signals, even in today’s crowded RF environment.

    Whether it’s surveying, autonomous systems, precision agriculture or defense, the AC4 ensures users can rely on GNSS data when it matters most.

    Designed with precision applications in mind:

    • Full GNSS band coverage. Supports GPS, Galileo, BeiDou, GLONASS, SBAS and correction services in one antenna, making it a versatile, future-proof solution.
    • Accutenna 4 technology. Four-feed compact stacked composite patch antenna minimizes multipath interference and keeps the phase centre stable, ensuring centimetre-level accuracy.
    • Lightweight, rugged options. Available as embedded (85 g) and in multiple mounting styles for diverse applications, from embedded systems to demanding field use.
    • Noise rejection. Integrated Extended Filtering (XF) technology blocks interference from new LTE and other signals that can disrupt GNSS performance.

    With the Accutenna 4, Calian GNSS expands its portfolio, reinforcing its role as a partner for organizations that depend on precision GNSS antenna innovation.