Peter Thompson, Ph.D., CEO of NPL, left, with Jim McDonald, professor at the University of Strathclyde. (Image: NPL)
The National Physical Laboratory (NPL) has marked the inauguration of the first of three innovation nodes designed to enhance the United Kingdom’s capabilities in the development of time-critical technologies. The initiative is aimed at sectors such as transport, telecommunications, fintech and quantum with the application of accurate and precise timing.
In a collaborative effort between NPL and host organizations, including the University of Strathclyde, the University of Surrey and Cranfield University, the Innovation Nodes stand as a cornerstone of NPL’s National Timing Centre Programme. It represents the UK’s nationally distributed time infrastructure and offers secure, reliable, resilient and highly accurate time and frequency data. This infrastructure is crucial for the development of new technologies in time-critical 5G and 6G applications, next-generation automated factories and connected autonomous vehicles.
Throughout the development phase, the node sites at the Universities of Strathclyde, Surrey and Cranfield have hosted feasibility and demonstrator projects funded by Innovate UK, the United Kingdom’s innovation agency. These projects have benefited from technical consultancy and access to high-accuracy timing signals, which encourage the development of new products and services. These initiatives were created as an effort to establish an evidence base for redistributing positioning, navigation and timing (PNT) data to air and ground-based autonomous systems within a smart city infrastructure. This will ensure the safety, reliability and security of autonomous transport.
NPL welcomes collaboration with industry and academia to leverage the Innovation Nodes for access to traceable and high-accuracy timing signals and promises to stimulate further innovation and development in critical sectors.
Professor Paul Griffin of Strathclyde’s Department of Physics pointed out the vulnerabilities of GNSS to jamming and spoofing, underscoring the NTC’s mission to provide robust timing for the UK independent of GNSS. The initiative includes the use of atomic clocks at Anthorn in Cumbria, aligning with UTC through the NPL Time Over eLoran (NTOL) project, led by Chronos Technology. This project demonstrates the transmission of NPL’s timebase via eLORAN and its decoding by Strathclyde’s Power Networks Demonstration Center (PNDC), which is a significant advancement in securing the country’s timing infrastructure against potential threats.
u-blox has partnered with Cellular Tracking Technologies (CTT), a specialist in wildlife telemetry and Internet of Things (IoT) solutions, in an initiative aimed at conserving Antarctic wildlife.
The collaboration has introduced a cloud-based positioning solution to monitor the activities of Adélie penguins in Ross Island, Antarctica. The venture began when Point Blue, an American wildlife conservation organization, reached out to CTT to create a tracking mechanism that could study the movements of young Adélie penguins. These birds are among the five penguin species inhabiting Antarctica and are considered crucial for environmental studies due to their sensitivity to ecological shifts caused by climate change and human activities, such as commercial fishing.
Due to the challenging conditions in Antarctica, tracking penguins required a device that was lightweight, non-intrusive, energy-efficient, and cost-effective in terms of data transmission. This was particularly important given the small size of the penguins, their rapid movement, and their extended underwater dives.
u-blox provided its CloudLocate positioning service to meet these stringent requirements, which led to the development of CTT’s Penguin Iridium GNSS tracker. The tracker is fixed to the penguins’ backs and uses one of u-blox’s compact GNSS modules. The CloudLocate service processes the positioning calculation in the cloud rather than on the device to save energy and enable prolonged monitoring periods without the need for frequent device replacements.
The tracker operates by sending a concise 50 B message, which captures essential location data during the brief moments when a penguin surfaces for air. This level of efficiency is critical in minimizing the costs associated with satellite connectivity, which is often prohibitively expensive in such remote regions.
This partnership marks an advancement in wildlife conservation technology by allowing for non-invasive, continuous monitoring of Adélie penguins and providing vital data for assessing the impacts of environmental changes. CTT aims to extend this tracking solution to a wider range of wildlife research and conservation projects to demonstrate the potential for technological innovation to contribute significantly to ecological preservation efforts.
A plane carrying British Defense Secretary Grant Shapps had its satellite signal jammed as it flew near Russian territory, the government reported on March 14.
The government said that the Royal Air Force jet carrying Shapps, officials and journalists “temporarily experienced GPS jamming when they flew close to Kaliningrad” on a flight from Poland to the UK.
The Times of London, whose reporter was onboard, said that for about 30 minutes mobile phones could not connect to the internet and the aircraft was forced to use alternative methods to determine its location.
Kaliningrad is a Russian enclave bordered by Poland and Lithuania, home to the Russian Navy’s Baltic Fleet. Prime Minister Rishi Sunak’s spokesman, Dave Pares, said “the jamming didn’t threaten the safety of the aircraft at any point.” He added that it is not unusual for aircraft to experience electronic jamming near Kaliningrad.
infiniDome, a provider of GPS protection and resilient navigation solutions, has opened infiniDome USA, a new subsidiary designed to enhance service to the United States defense industry.
By establishing infiniDome USA, infiniDome aims to strengthen its relationships with U.S. customers, offering more localized support and ensuring that its innovative GPS protection technologies meet the specific needs and challenges faced by American aerospace and defense sectors.
infiniDome’s anti-jamming technology offers resilience and reliability to critical systems across a variety of sectors including defense, timing systems, aviation, and autonomous vehicles.
According to the company, infiniDome’s expansion to the U.S. comes in response to the critical need for enhanced proportional GPS security measures amidst the growing threats to GPS-dependent technologies. In direct correlation to government and industry projects, calling for small, light, “attritable” UAVs, protection for such platforms also must be proportional in size, weight, and cost.
infiniDome invites industry partners, customers, and media to learn more about infiniDome USA and its advanced GPS protection and navigation resiliency solutions at AUVSI Xponential 2024 in San Diego, which takes place April 22 to 25.
Saildrone has released its first aluminum Surveyor unmanned surface vehicle (USV) off the Austal USA production line in Mobile, Alabama. Chief of Naval Operations (CNO) Lisa Franchetti was on site to inspect the vehicle, ahead of these new USVs being tested under contract to the U.S. Navy.
The Surveyor USV is primarily designed for ocean mapping and maritime domain awareness. The wind, solar power and a diesel generator for long-range, long-endurance missions in the open ocean power it.
The Surveyor is equipped with the latest multibeam sonar technology, which enables it to map the seafloor up to a depth of 11,000 m. Additionally, it can carry defense and security payloads that are specifically designed to detect and respond to various maritime threats and challenges.
Upcoming Navy missions will focus on the ability of the Surveyor to deliver both surface and undersea intelligence for a range of high-priority applications, including anti-submarine warfare (ASW).
To meet the increasing demand for Surveyor USVs, Saildrone partnered with Austal USA, an Alabama-based ship manufacturer, to produce one Surveyor every six weeks, with the ability to scale up production as demand requires.
At 20 m long and weighing 15 tons, the Surveyor classifies as a medium USV, built to American Bureau of Shipping (ABS) Light Warship code. These first Surveyors are contracted to the U.S. Navy to test and evaluate Surveyor-class vehicles in multiple environments.
Abracon has partnered with u-blox to combine the u-blox ZED-F9P GNSS receiver module and the Abracon APXG6016GH full-band, multi-constellation active GNSS antenna. This pairing offers centimeter-level accuracy designed for a variety of industries such as precision agriculture and mobile robotics.
The APXG6016GH antenna is designed with a robust pre-filtered low-noise amplifier (LNA), which offers strong anti-interference performance in challenging environments. It supports multi-frequency reception, including L1, L2, L5, and L-band correction services, for robust signal reception and enhanced accuracy.
The u-blox ZED-F9P module is designed to provide precise and reliable performance in various applications. When combined with the Abracon APXG6016GH antenna, this module gives users access to accurate positioning data critical for demanding navigation tasks.
The Abracon APXG6016GH antenna features tightly grouped phase center variation with advanced multi-feeding technology, which provides consistent performance across various scenarios. Its compact and lightweight design makes it ideal for portability and UAV applications, providing users with flexibility and ease of integration.
Working in agriculture means facing a variety of challenges imposed by nature. Unfavorable weather conditions, such as irregular rainfall, strong winds and hail, are common obstacles for producers and companies involved in the sector. Additionally, a recent rise in solar flares has caused headaches for those who rely on precision agriculture technologies, such as satellite positioning technologies, to operate farm machinery.
Ionospheric scintillation is a phenomenon that causes rapid and irregular variations in the power of radio frequency signals that travel through the ionosphere, a region of the Earth’s atmosphere that has ionized particles, which makes it capable of reflecting and refracting radio signals, such as those used in satellite communications and GNSS.
These variations in the power of radio signals occur due to disturbances in the concentrations of free electrons in the ionosphere, which various factors, including solar activity, geomagnetic events and weather conditions in the upper atmosphere can influence. Fluctuations in the electron density of the ionosphere cause distortions in radio signals, leading to fluctuations in the signal’s power and phase. Some of the consequences of this phenomenon are almost imperceptible, such as a deviation of 1 m or 2 m in the position calculated by your cell phone’s GPS receiver. When it comes to precision farming, however, a few centimeters of error in machine positioning can severely impact operations by increasing input waste, reducing efficiency and decreasing production.
Many farmers, especially in Brazil, plant and harvest two crops a year, and rely on precision farming technology to sow and harvest quickly and accurately. With an estimated production of 317.5 million tons for the 2023/24 harvest, according to the Brazilian National Supply Company (Conab), these producers have buffer time to keep their machines idle. During planting and harvesting periods, farms often operate 24 hours a day, 7 days a week, and precise positioning via GNSS is essential for using solutions such as auto-steering and traffic control. When ionospheric scintillation affects the performance of location systems, it causes delays and inaccuracies, directly impacting the productivity of farms and damaging the operations’ efficiency and profitability.
To mitigate the impacts caused by ionospheric scintillation, as well as other problems that can affect receivers, farmers have several GNSS correction options at their disposal, such as precise point positioning (PPP) and real-time kinematics (RTK). These alternatives aim to increase positioning accuracy for high-precision applications and create different levels of resilience against ionospheric interference. However, it can still affect these services, causing errors in the receiver’s position calculations. In RTK systems, which rely on carrier phase measurements, scintillation can drastically impair positioning accuracy, especially at greater distances from the base station.
To overcome scintillation challenges, PPP positioning is a more reliable option. Unlike RTK, PPP estimates ionospheric errors at the receiver’s location and does not depend on corrections from a local base station. This allows users to achieve high precision anywhere within the global coverage area, regardless of the distance from the base station. In addition, PPP takes into account the immediate ionospheric environment, making it less sensitive to changes in atmospheric activity.
A study by Hexagon | NovAtel in 2020, analyzed the ionospheric activity in the central-western region of Brazil, comparing a standard RTK positioning solution and the PPP TerraStar-C PRO positioning solution, developed by NovAtel. A 24-hour data collection captured the nocturnal impacts of ionospheric activity and yielded some insights: while RTK position performance at 10 km from the base station was degraded for many hours, showing errors of up to 25 cm, the receiver using TerraStar-C PRO corrections continues to experience centimeter-level accuracy, with shorter maximum deviations of up to 10 cm.
In summary, ionospheric scintillation is a growing challenge for precision agriculture, affecting the productivity and efficiency of agricultural operations. To minimize its impacts, the adoption of correction services such as TerraStar-C PRO has proven to be a resilient and reliable solution, allowing farmers to continue their operations accurately and effectively, even in challenging conditions. The development of increasingly advanced precision solutions is crucial to ensuring the success of agriculture.
FrontierSI, a not-for-profit research organization specializing in positioning, geodesy, spatial infrastructures and rapid spatial analytics, has released a review of Australia’s resilient positioning, navigation and timing (PNT) policy to fortify the country’s PNT infrastructure. The review, expanded upon in a new white paper and technical report, was created in response to the increasing number of cyber threats.
“PNT is an essential utility we presently have no control over,” said Joshua Critchley-Marrows, FrontierSI’s space PNT lead. “Australia’s access to PNT is intrinsically linked to satellite-delivered services from foreign-owned and operated assets, such as the USA’s Global Positioning System (GPS). Investing in our infrastructure is crucial to ensure continuous access to this critical service that underpins nearly all aspects of our daily lives.”
According to FronteirSI, the reliance on foreign satellite systems exposes Australia to significant vulnerabilities, such as recent technological failures and cyber-attacks. These incidents emphasize the need for a self-reliant and robust PNT ecosystem capable of withstanding both unintentional and malicious disruptions.
FrontierSI aims to bolster PNT resilience by enhancing the systems’ robustness against disruptions and advocating for the development of assured, robust, augmented and alternative PNT solutions. The recommendations outlined in the white paper and technical report call for proactive measures, including legislative updates and supply chain risk assessments, to protect Australia’s critical infrastructure and economic vitality.
A roundup of recent products in the GNSS and inertial positioning industry from the March 2024 issue of GPS World magazine.
SURVEYING & MAPPING
GNSS Receiver Supports tilted measurement
PozStar P5 is a high-precision GNSS receiver. It is powered by a 1,408-channel multi-band GNSS receiver designed to improve surveying in the field. It is equipped with Bluetooth, WiFi and UHF radio. The inertial measuring unit (IMU) supports tilted measurement, which allows users to obtain quick initialization and accurate measurements with an inclination of up to 60°.
The receiver comes with radio connector options used in a frequency range of 410 MHz to 470 MHz and a 5-pin serial port, which allows for external radio system connectivity and NMEA data output. It is also weatherproof, rated IP67.
PozStar P5 can collect control and surveying data for RTK equipment to perform surveying, map input and drawing operations. The receiver can be used with PozPad, an Android-based RTK field software.
PozStar, pozstar.com
Lidar System Designed for aerial surveying
The TrueView 540 lidar system integrates lidar technology with LP360 3D point cloud processing software to enhance survey-grade lidar applications.
The system is designed to provide enhanced data density, accuracy, and precision for aerial surveying. It combines lidar, an accurate positioning and orientation system and a full-frame industrial camera in a compact, lightweight package. It is suitable for a variety of UAVs, including the DJI Matrice 350.
The TrueView 540 features high-precision lidar technology comparable to high-end industry-standard payloads in terms of range, density and accuracy. It will be made available through GeoCue and its authorized distributors. GeoCue, geocue.com
GNSS Solution Combined with Septentrio’s mosaic-X5 module
The SparkFun real-time kinematics (RTK) mosaic-X5 uses the multi-constellation, multi-frequency capabilities of the Septentrio mosaic-X5 module, which aims to improve accuracy and reliability in a variety of position applications.
The RTK mosaic-X5 is a 448-channel receiver that supports all four Global Navigation Satellite Systems (GNSS) — GPS, GLONASS, BeiDou and Galileo — and one of the two regional ones, NavIC. It can function as both an RTK base and rover, which allows users to achieve horizontal positioning accuracy down to 6 mm and updates at a rate of 100 Hz.
The device incorporates the Espressif ESP32-WROVER processor, which allows for high-speed processing and a variety of connectivity options. The ESP32 provides the device with USB-C, Ethernet-over-USB and an Ethernet to WiFi Bridge mode to ensure seamless integration into any project setup.
The device also has power flexibility, including USB-C, Power-over-Ethernet, and external DC sources, along with data logging in multiple formats such as RINEX and NMEA. Housed in a custom-designed aluminum case, the RTK mosaic-X5 features a comprehensive web server interface to simplify configuration and monitoring. SparkFun Electronics, sparkfun.com
Hybrid Mobile Mapping Solution Combines mobile scanning with a stationary mode
The X70GO SLAM laser scanner is designed for fast and efficient large-area surveys. It combines mobile scanning with a stationary mode to scan with high resolution to enhance overall surveying capabilities.
X70GO is a real-time 3D model reconstruction device that integrates an inertial navigation module, high-performance computer and storage system. It is equipped with a 360° rotating head, which, combined with the SLAM algorithm, can generate high-precision point cloud data. The built-in 512GB memory disk stores survey results and the dismountable handle has a 1.5-hour battery life.
A 12MP RGB camera offers texture information, while a visual camera aims to enhance the real-time preview with the GOapp. Mapping results can be generated immediately inside the scanner. Users can then color the points and improve their accuracy during post-processing with GOpost software.
The system comes with a hybrid scanning capability. The X-Whizz mode combines the advantages of SLAM mode with the resolution of a static scan, which eliminates the need for multiple scan stations. Users can move around the scene to collect the entire 3D point cloud without time-consuming cloud-to-cloud alignment.
The technology incorporated in the new scanner is designed to provide extended range, a higher number of points per second and advanced onboard processing algorithms. The SLAM laser scanner is well-suited for challenging environments and can be used in a variety of applications, including BIM, industrial sites, real estate, heritage preservation, tunnels and mining.
Users can add an RTK module to set a point cloud in a global coordinate system. This can support adding GNSS information to that from lidar and the inertial measurement unit (IMU) in the SLAM algorithm. In situations with limited GPS connectivity – such as indoors or in challenging environments – the system will rely on lidar and the IMU for positioning purposes. Stonex, stonex.it
Remote Sensing Payload Integrates with UAVs and other platforms
The RESEPI lidar Gen-II remote sensing payload instrument comes in three modes: aerial mode for comprehensive airborne data collection, mobile mode for dynamic vehicular data collection and a versatile handheld/backpack that aims to provide portability and ease of use for ground personnel.
The RESEPI lidar Gen-II has a 175% increase in computing power, designed to speed up processing and enhance efficiency during complex tasks. Its memory capacity has been increased by 700%, which allows for extensive data handling and improved system performance. The system’s 50% increase in storage capacity aims to facilitate longer durations of data collection without frequent offloads.
The Gen-II features seamless integration capabilities with UAVs and other platforms. The system’s sensor-agnostic design allows for external sensors to be easily integrated, including lidar and cameras. It also can compute point clouds, trajectories and solutions in real-time, which is critical in time-sensitive missions. The system can be used in a variety of applications including mapping, inspection, autonomous vehicles, navigation and robotics. Inertial Labs, inertiallabs.com
Mapping Software With upgraded cloud capabilities
The Correlator3D mapping software now has upgraded cloud capabilities. With its distributed processing capabilities, Correlator3D allows users to scale their processing to match individual operational needs.
With the upgrade, Correlator3D can process large mapping projects and deliver results from UAV, aircraft and satellite imagery. It features a software package – a patented, end-to-end photogrammetry solution — designed to generate high-quality geospatial data from a variety of sources, including satellite and aerial imagery and UAVs. The upgrade aims to improve the technology’s performance in diverse cloud scenarios.
Correlator3D is designed to provide aerial triangulation (AT) and generate dense digital surface models (DSM), precise digital terrain models (DTM), point clouds, orthomosaics, 3D models and vectorized 3D features. By using GPU technology and multi-core CPUs, Correlator3D offers enhanced processing speed to support the rapid production of large datasets. SimActive, simactive.com
MOBILE
Handheld GNSS Data Collector Ideal for construction surveying
TDC6 is a handheld GNSS data collector designed for high-performance construction surveying. The device allows contractors to work with more complex data sets more effectively in the field, connect to the office for on-the-spot approvals, and quickly communicate changes to field crews.
The small, rugged device offers integrated Wi-Fi and Bluetooth, built-in cameras and 5G compatibility in a lightweight, shock-, dust- and water-resistant package. The device integrates seamlessly with Trimble data collection applications, including Trimble TerraFlex GIS software and Trimble Access survey field software, as well as third-party apps such as Esri ArcGIS Field Maps. Trimble Geospatial, geospatial.trimble.com
Military-Grade Antennas Designed for mission-critical applications
This advanced military-grade antenna product line includes ruggedized GPS, manpack omni and vehicle omni antennas. The products are designed for mission-critical applications such as vehicle navigation, personnel communications, vehicle communications, electronic warfare, and jamming.
The antennas meet MIL-STD-810 to offer durability while adhering to strict quality standards. The antennas also are compliant with the Trade Agreements Act (TAA), which makes them suitable for government and defense applications.
Built to withstand tough conditions, these antennas feature heavy-duty construction and a rugged design for long-lasting performance in challenging environments. They are designed to perform in extreme weather conditions and on rough terrains.
Its robust construction and NATO/U.S. standard mounting options aim to simplify integration into various setups during critical operations. Fairview Microwave, fairviewmicrowave.com
Trimble SiteVision Software 5.0. (Image: Trimble)
Outdoor Augmented Reality System With 3D scanning capabilities
SiteVision Software 5.0 is a high-accuracy outdoor augmented reality system, now with a 3D scan tool. The new 3D scan tool allows users to use lidar sensors available on some Apple Pro devices. The Trimble DA2 GNSS receiver is designed to capture point clouds efficiently and accurately with a single handheld solution.
Users can visualize 3D scan data directly in the field with SiteVision’s augmented reality view. The software allows users to create as-builts of the job site on the go, measure and plan resource allocation, reduce scan times, supplement UAV data and more by combining scanning and precision in a mobile solution. The product aims to facilitate practical and accessible field-to-office workflows for surveyors, contractors and engineers.
Trimble Geospatial, geospatial.trimble.com
OEM
Two LTE Modules With integrated GNSS
The LTE-M cellular module series, the SARA-R52 and LEXI-R52, are designed to meet the needs of industrial applications requiring both positioning and wireless communication capabilities. Based on the u-blox UBX-R52 cellular chip, these modules are designed for a variety of internet of things (IoT) use cases, including both fixed and mobile applications.
The UBX-R52 chip is designed to simplify product design by reducing the need for additional components. It includes SpotNow, a positioning function developed by u-blox, which aims to provide location data with an accuracy of up to 10 m within a few seconds. This function is targeted at applications requiring occasional tracking, such as waste management, personal trackers and industrial machinery.
The chip’s uCPU feature allows the execution of custom software directly on the chip and eliminates the necessity for an external microcontroller unit (MCU). The smart connection manager (uSCM) is a feature designed to manage connectivity automatically, focusing on optimizing performance or minimizing power consumption under varying connection conditions.
The R52 series introduces the SARA-R520M10 combo module, which is equipped with an integrated u-blox M10 GNSS receiver. This module is designed to provide simultaneous GNSS and cellular connectivity, supporting applications that require continuous or periodic tracking with features such as low power consumption, improved time-to-first-fix (TTFF) and increased RF sensitivity.
Unlike many LTE-M modules that typically offer an RF output power of 20-21 dBm, the new R52 series modules offer a higher output power of 23 dBm to improve connectivity in difficult coverage areas. The LEXI-R52 offers the same functionalities as the SARA-R52 but comes in a smaller form factor, making it ideal for applications with space constraints, such as wearable technology.
These additions to u-blox’s LTE-M module portfolio are designed to address the integration of GNSS and wireless communication in industrial IoT applications, offering solutions for a range of use cases that require robust connectivity. u-blox,u-blox.com
UAV
GNSS-Denied Navigation Kit For challenging environments
This GNSS-denied navigation kit is designed to offer navigation capabilities in challenging environments. It combines UAV Navigation’s attitude and heading reference system (AHRS), the POLAR-300, with its Visual Navigation System, the VNS01, to offer advanced dead reckoning navigation capabilities with minimal drift.
The technology has error rates as low as 0% to 1% over covered distances. This is made possible by the kit’s visual-based technology, which allows for precise attitude and position estimation to stabilize flights in challenging conditions. The kit is equipped with advanced algorithms that can detect and counter sophisticated spoofing and jamming techniques to offer reliable and secure navigation, even in the face of potential signal disruptions. The kit can be used in both civil and defense sectors.
UAV Navigation-Grupo Oesía, uavnavigation.com
Lidar UAV Solution Offers immediate access to terrain information
The lidar UAV mapping solution combines the WingtraOne GEN II UAV with a newly developed lidar sensor. This integration aims to advance UAV lidar efficiency, increase accuracy and simplify integration.
The solution incorporates a Hesai scanner, Inertial Labs IMU and NovAtel GNSS receiver designed to optimize data acquisition and reduce the need for post-processing strip alignment. This advancement offers immediate access to precise terrain information following each flight and enhances the efficiency of mapping and photogrammetric analysis in various sectors.
One of the key features of the lidar system is its reduced field time, with no calibration needed and a one-minute initialization process. The Wingtra lidar application and the system’s automated features offer a streamlined data capture process, which makes it accessible even to those new to lidar technology.
The solution offers a vertical accuracy of 3 cm from a 60 m flight height, with leading point density in its class. The WingtraOne GEN II’s design and automated flight patterns offer consistent results across different pilots. Wingtra, wingtra.com
MACHINE CONTROL
GNSS Smart Antenna Designed for industrial environments
AntaRx-Si3 is a GNSS/INS smart antenna housed in an ultra-rugged enclosure, designed for straightforward installation on machinery such as agricultural robots. It combines Septentrio’s centimeter-level GNSS positioning with an inertial measurement unit (IMU) within the same enclosure as the GNSS antenna, which uses FUSE+ technology.
The AntaRx-Si3 is designed for challenging industrial environments where GNSS signals are at risk of obstruction, such as under heavy foliage. The antenna’s exterior is crafted from impact-resistant polycarbonate with an IP69K rating and can withstand significant shocks, vibrations, and harsh environmental conditions.
It uses Septentrio’s GNSS+ algorithms to offer advanced multipath mitigation to operate in environments where satellite signals could be reflected off surrounding machinery or structures, such as silos. The antenna delivers high update rates and low latency positioning, which are crucial for the control loops of autonomous movements or rotations. Septentrio, septentrio.com
3D Machine Control Software Suitable for construction sites
The Leica MC1 software platform is designed to guide and automate machine control solutions.
Leica MC1 machine control software continues to evolve toward achieving a smart digital reality, with features such as Modify Models and surface logging. It compares the design model to the actual position of the machine’s cutting edge, such as the bucket or blade edge. The technology aims to assist operators in positioning machinery to achieve the planned design while allowing for a live digital representation of the progress. The software automatically controls the position of the machine’s cutting edge.
It is carried by the rugged hardware platform, the Leica MCP80 panel and MDS Series docking station, offering an interchangeable panel between machines on a job site. The MC1 platform is supported by the cloud-based Leica ConX productivity platform to offer more efficient management of heavy construction projects.
Leica Geosystems, part of Hexagon, leica-geosystems.com
Abracon has introduced a new series of GNSS RF antennas designed to elevate location-based services with enhanced accuracy and precision. This new lineup aims to outperform conventional GPS technologies by offering faster signal acquisition, improved tracking capabilities and reduced power consumption.
The antennas support a full spectrum of bands, including L1, L2, L5, and L-band data correction services. It can be used in a variety of sectors — such as agriculture, surveying, the Internet of Things (IoT), mapping, defense and aviation.
The technology is designed to meet the rigorous demands for precise location data across various applications. These antennas offer multi-band and multi-constellation support to ensure broad compatibility. With centimeter-level accuracy, these antennas are crucial for aerospace, defense, asset tracking, geolocation, precision agriculture and industrial IoT.
The civil infrastructures behind safety-critical applications in aviation, maritime and terrestrial navigation rely heavily on global navigation satellite system (GNSS) signals. The civil GNSS signal structures are vulnerable to spoofing attacks, which can endanger public safety.
In this work, the authors introduced an optimal cumulative position-domain innovation (CPI) monitor to detect spoofing by accumulating tracking errors embedded in the spoofer’s signal. The authors also derived relationships between missed detection probability, tracking error magnitude and monitor run time to show that even with decimeter-level tracking error, the monitor can detect spoofing with a low probability of missed detection in less than 1 minute.
The team of researchers evaluated the performance of the CPI monitor for both white and time-correlated (colored) tracking errors. To compute protection levels and detect short-duration spoofing, researchers proposed a complementary solution separation (SS) monitor to implement in sequential, overlapping windows to compare the integrated INS/GNSS position solution against an inertial navigation system (INS) coasting solution. The INS-only coasting element allows the system to maintain positioning continuity after detection, albeit at lower accuracy, as the INS drifts.
The experimental results indicate that implementing a CPI monitor can dismiss the conjecture that INS-based spoofing detection is susceptible to slowly deviating counterfeit signals. It was found that if the duration of the spoofing event exceeds a minimum time defined by the variance and time constant of the tracking error, the spoofer’s target tracking error can be detected.
Birendra Kujur, Samer Khanafseh and Boris Pervan; “Optimal INS Monitor for GNSS Spoofer Tracking Error Detection.”
Space-Time Adaptive Processing
Antenna arrays and spatial processing techniques are among the most effective countermeasures against GNSS signal interference. In this paper, the authors propose a new array concept, space-time adaptive processing (STAP), that consists of spatially distributed subarrays small enough to fit inside the non-metallic parts of an automobile. The device is designed to be installed in bumpers or side mirrors.
During the experimental testing, the authors used beamforming algorithms for the array to perform against jammers in the GPS L5 and Galileo E5a bands. The authors composed a GNSS jamming scenario to compare conventional space adaptive processing (SAP) methods and the new STAP method using real-life measurements in a dynamic scenario. In this simulation, the car was rotated 360° throughout the complete measurement. The comparison between the received signal quality demonstrated an improvement for wideband signals.
The results demonstrate that the performance of the STAP was dependent on the number of taps analyzed in the testing simulation that included different fractional delays. Overall, the research showed STAP could outperform SAP implementation in applications requiring robust tracking, as it was able to process all satellites for an additional 12 seconds.
Marius Brachvogel, Michael Niestroj, Michael Meurer, Syed N. Hasnain, Ralf Stephan and Matthias A. Hein; “Space-Time Adaptive Processing as a Solution for Mitigating Interference Using Spatially-Distributed Antenna Arrays.”
Enabling RTK Positioning Under Jamming
New GNSS applications demand high position accuracy and resilience against radio frequency interference. Separately, these demands can be fulfilled by multi-antenna systems using spatial filtering and carrier-phase positioning algorithms, such as real-time kinematics (RTK), respectively. However, combining these approaches creates a severe issue: the spatial filtering induces a phase offset into the measured carrier phase leading to a loss of position accuracy.
This paper presents a new approach to compensate for the phase offset without knowing the antenna array radiation pattern or the direction of arrival of the signals. The proposed algorithm was tested in two different scenarios using an in-house software receiver in combination with the RTKlib — an open-source program package for GNSS positioning — that was used to estimate an RTK solution. In the first scenario, the signal power of a jammer from a constant direction of arrival (DoA) was raised stepwise. In the second scenario, a jammer with constant signal power was moved around the receiver antenna array. For both scenarios, the proposed algorithm was compared with a multi-antenna system not compensating for the phase bias and with a single antenna processing.
It is most suitable in situations where a medium-to-high precision (dm to cm) solution must be resilient to interference. A very high precision solution (cm to mm), comparable with a geodetic receiver accounting for antenna phase center variations, cannot be achieved with this algorithm.
In this paper, the signal recording and processing time was limited to less than half an hour. The carrier-phase offset produced by the proposed algorithm may become larger over longer observation times. Evaluating this is part of future work.
Tobias Bamberg, Andriy Konovaltsev and Michael Meurer; “Enabling RTK Positioning Under Jamming: Mitigation of Carrier-Phase Distortions Induced by Blind Spatial Filtering.”
Several layers of defense can be implemented in a GNSS receiver to improve its performance in the presence of interference. These layers include the use of pre-correlation mitigation techniques, post-correlation quality indicators to screen measurements and fault detection and exclusion (FDE) at the position solution level.
This paper provides a characterization of the interactions between these layers of interference mitigation and a measurement quality check. Data collected in the presence of increasing levels of jamming were processed using different interference mitigation techniques, including robust interference mitigation (RIM) and the adaptive notch filter (ANF). A software-defined radio (SDR) approach was used, and measurements were generated by considering five interference-mitigation techniques. Position solutions were then computed using a forward-backward approach for receiver autonomous integrity monitoring (RAIM). Signals from GPS, Galileo and BeiDou were processed and both single and dual-constellation solutions were analyzed.
The results demonstrated that interference mitigation allowed the receiver to track a larger number of signals even in the presence of high levels of jamming power. This increased measurement availability was then effectively exploited by RAIM techniques to provide more reliable solutions. Measurements from several constellations further improved the reliable availability of the position solutions.
Ciro Gioia and Daniele Borio; “Multi-layered Multi-Constellation Global Navigation Satellite System Interference Mitigation.”
OxTS’ GNSS-aided inertial navigation systems (INS) are now supported on the NVIDIA DRIVE autonomous vehicle (AV) development platform. The software plug-in, developed in-house by OxTS using the NVIDIA DriveWorks SDK, runs on the NVIDIA DRIVE AGX Orin developer kit.
The plug-in gives developers using NVIDIA DRIVE the ability to feed OxTS GNSS/INS data directly into the platform to access accurate reference localization data as ground truth and validate the performance of the other sensors or algorithms under test.
A GNSS/INS is only one of several sensors required for an AV to operate. These sensors create a vast amount of data that must be synchronized, calibrated and centrally processed for the vehicle to operate safely. The OxTS GNSS/INS offers precision time protocol (PTP) time synchronization and can serve as the reference to calibrate all the other sensor data back for data analysis.
The OxTS RT3000 series is the GNSS/INS device supported on the NVIDIA DRIVE platform. It is currently being used as an advanced driver assistance system (ADAS) and vehicle dynamics ground-truth reference system for automotive test and validation teams across the globe.
The NVIDIA DRIVE platform is built on the DRIVE Orin system-on-a-chip and can process up to 254 trillion operations per second (TOPS) of sensor data from a variety of camera, lidar and radar devices.
