Artist’s rendition of a GPS-IIR satellite in orbit. (Image: GPS.gov)
The U.S. Space Force has announced the decommissioning of GPS satellite SVN-47 (PRN-22), which officially took place Jan. 18. The satellite has been unusable since Dec. 2.
SVN-47 was a replacement satellite in the second generation of GPS satellites (GPS-IIR), launched Dec. 21, 2003.
The announcement was made in a Notice Advisory to NavStar Users (NANU 2022001) issued by NAVCEN, U.S. Coast Guard.
The designation PRN-22 will be used to bring SVN-41 back in to the active constellation. After 2200 Zulu on Jan. 2o, GPS will transition SVN-41 (PRN-22) into the broadcast almanac for all satellites, and SVN-41 will resume transmitting L-band signals. The almanac transition, accomplished one satellite at a time, will require approximately 24 hours to complete.
A second NANU emphasized that “Before, during, and after transition SVN-41 (PRN22) will remain unusable until further notice.”
SVN-41, the sixth of the GPS-IIR satellites, was launched on Nov. 10, 2000, and set to active service a month later on Dec. 10. It was decommissioned in July 2021.
A roundup of recent products in the GNSS and inertial positioning industry from the January 2022 issue of GPS World magazine.
Surveying
Base Station
Receives all available GNSS signals
Photo: Trimble
The Trimble R750 GNSS modular receiver is a connected base station for use in civil construction, geospatial and agricultural applications. The R750 provides high-accuracy base-station performance, giving contractors, surveyors and farmers more reliable and precise positioning in the field. The R750 also can be used to broadcast real-time kinematic (RTK) corrections for a wide range of applications, including seismic surveying, monitoring, civil construction, precision agriculture and more. Access to all available satellite signals provides improved performance and reliability when used with a Trimble ProPoint GNSS rover. ProPoint gives users improved performance in challenging GNSS conditions, with improved signal management.
Trimble, trimble.com
Flight Planning
Updated for safer UAV surveying
Photo: Microdrones
The mdCockpit app was designed for professional drone users to make it easy to plan, monitor, change and control flights from an Android tablet. The updates in version 2021.3 include features that improve flight safety and give more options for surveying with an aim to deliver a premier solution for planning, monitoring, adjusting, analyzing and controlling professional drone flight missions from a tablet. Updates include an improved flight editor, flight data collection and drone configuration. Drone pilots can download mdCockpit through the Google Play store.
Microdrones, microdrones.com
OEM
LTE Module
With 2G fallback for Latin America
Photo: Telit
The LE910S1-ELG LTE Cat 1 module is designed for internet of things (IoT) applications in Latin America that need a combination of performance, affordability and voice support in a compact form factor. It provides 2G fallback, making it suitable for areas that have not upgraded to 4G. With an embedded GNSS receiver, the cost-optimized LE910S1-ELG is suitable for tracking applications such as fleet management, stolen-vehicle tracking and recovery, and other mobile IoT applications that need to maintain a reliable connection when moving around in a country, region or multiple regions. The power-saving embedded GNSS receiver enables the use of GNSS positioning even when the cellular modem is switched off.
Telit, telit.com
Flex Power
Capability now on constellation simulator
Photo: Spirent
A new positioning, navigation and timing (PNT) test capability commonly referred to as programmable power — or flex power — is available on the Spirent GSS9000 constellation simulator and can be applied to existing scenarios. Flex power is the reallocation of transmit power among individual signals in GPS satellites, providing a countermeasure against GPS jamming. Spirent simulators fully support programmable power for M-code, Y-code and C/A (coarse acquisition) code.
Spirent, spirent.com
GNSS Module
Automotive qualified with INS and dead reckoning
Photo: STMicroelectronics
The Teseo-VIC3DA is the latest member of the Teseo module family, designed for vehicle positioning. It combines the Teseo III GNSS integrated circuit with the 6-axis MEMS inertial measurement unit (IMU) and dead-reckoning software to provide super-high-resolution motion tracking for advanced vehicle navigation and telematics applications. Teseo III offers robust positioning capabilities by simultaneously receiving signals from GPS, Galileo, GLONASS, BeiDou and QZSS constellations. The module enables competitively priced in-car navigation, fleet management and insurance-monitoring applications.
STMicroelectronics, st.com
PNT Platform
Protects critical infrastructure from GNSS vulnerabilities
Photo: ADVA
The scalable aPNT+ platform meets the latest guidelines for resilient positioning, navigation and timing (PNT), providing end-to-end control and timing network visibility for robust protection against the catastrophic risks that PNT disruption poses to national security and essential assets such as power grids. Even without GPS or GNSS timing, the solution provides an intelligent, end-to-end self-recovery system designed around a three-fold framework, integrating multi-layer detection, multi-source backup and multi-level fault-tolerant mitigation.
ADVA, adva.com
Timing Antennas
IP67-compliant for outdoor and marine environments
Photo: RadioWaves
A new series of GPS/GNSS timing antennas cover the L1 and L5 GPS bands, providing axial ratio and higher accuracy for the reception of satellite timing signals and reference frequencies for enhanced phase synchronization in precision network deployments. Their high gain, low noise figure of 2-dB and high out-of-band rejection allows for use of longer and cost-effective cables for easy and flexible installations. Built-in surge protection supports a wide range of GNSS including GPS, GLONASS, BeiDou and Galileo, as well as Iridium.
RadioWaves, radiowaves.com
Mapping
Imaging System
Designed for utility and infrastructure mapping
Photo: Geocue
True View 435 is an economical platform for utility-grade mapping, with superior ground-capturing capabilities for lightly vegetated areas. The next-generation compact 3D imaging system has the sensitivity needed for infrastructure mapping. Its position and orientation system is the Applanix APX-15, achieving accuracy of better than 5 cm RMSE and precision of better than 5 cm at 1 sigma.
GeoCue, geocue.com
Long-Range Scanner
Includes integrated GNSS receiver
Photo: Riegl
The VZ-2000i long-range 3D laser scanning system combines user friendliness with fast, accurate data acquisition. The flexible system includes an integrated GNSS unit for a high-accuracy real-time kinematic (RTK) solution. Other peripherals and accessories include a SIM card slot for 3G/4G LTE, WLAN, LAN, USB and other ports. A new processing architecture enables execution of different background tasks onboard in parallel to the simultaneous acquisition of scan data and image data, such as point-cloud registration, georeferencing and orientation via an integrated inertial measurement unit.
RIEGL, riegl.com
Transportation
Vehicle Antennas
Designed for Intelligent connected cars and trucks
Photo: Harxon
Two new GNSS antennas are designed for vehicles equipped with advanced sensors, controllers, actuators and other devices. They are enabled for intelligent information exchanges between the vehicle and everything (V2X), connecting autos with GNSS, 5G, Wi-Fi, ultra-wideband and more. The integrated antennas support dedicated short-range (DSRC) and cellular vehicle-to-everything (C-V2X) communication, embedding a premium GNSS antenna with high gain for consistent and reliable precise positioning service. They also allow for multiple input and output of data to achieve swift internet download speed in 5G networks.
Harxon, harxon.com
NVIDIA AV Support
Receiver now supported on autonomous platform
Photo: NovAtel
The PwrPak7-E1 GNSS receiver is now supported on the NVIDIA Drive Hyperion autonomous vehicle (AV) development platform. Selected for its robustness and precise position output, the PwrPak7-E1 will be offered with NVIDIA’s autonomous driving test fleets worldwide. Drive Hyperion is a fully operational, production-validated and open AV platform that reduces the time and cost required to outfit vehicles with autonomous driving and artificial intelligence (AI) features. The PwrPak7-E1 also is now compatible with NVIDIA’s DriveWorks v4 software release.
Hexagon | NovAtel, novatel.com
Splitter
Provides signals to two GNSS receivers
Photo: Tallysman
The TW162A automotive-grade smart power GNSS signal splitter supports the full GNSS spectrum: GPS/QZSS-L1/L2/L5, QZSS-L6, GLONASS-G1/G2/G3, Galileo-E1/E5a/E5b/E6, BeiDou-B1/B2/B2a/B3 and L-band correction service frequency band. It offers fail-over and fault-identification features. The splitter accepts power from all attached GNSS receivers; if one receiver fails, the next attached receiver automatically provides power to the splitter and antenna. If the antenna fails and does not draw current, all connected receivers will sense a current draw lower than 1 mA, indicating an antenna fault. The TW162A offers high performance in terms of noise figure, isolation and linearity.
Tallysman, tallysman.com
ADS-B Receiver
Enhances airport situational awareness
Photo: uAvionix
The pingStation 3 integrates 978 MHz and 1090 MHz ADS-B receivers, a GPS receiver, an antenna and a power-over-Ethernet (POE) interface into an easy-to-install, rugged weatherproof enclosure. With a selection of non-proprietary and industry-standard data interfaces, such as JSON and ASTERIX CAT 021, pingStation 3 is designed to integrate into a multitude of end-user applications, including airport displays, UAS Ground Control Stations (GCS), Unmanned Traffic Management (UTM) Solutions, and Flight Information Displays (FID). When paired with the VTU-20 airport vehicle ADS-B transmitter, pingStation 3 improves the situational awareness of ATCs and the safety of airport operations by reducing the risk of runway incursions.
uAvionix, uavionix.com
UAV
Defense UAS
Flexible UAV and control software combined
Photo: Ascent AeroSystems
Ascent AeroSystems’ Spirit coaxial unmanned aerial system (UAS) offers a versatile and durable system for mission-critical operations. With a modular, plug-and-play payload design, the Spirit’s open architecture allows operators to add or upgrade software to unlock new operating capabilities without the need to design or develop a new aircraft. Autonodyne’s additive software solution allows the Spirit to perform autonomous tasks either individually or as a team with multiple vehicles, from a single operator and control station.
Ascent AeroSystems, ascentaerosystems.com
Autonodyne, autonodyne.com
Evaluation Kits
Now include mosaic Septentrio modules
Photo: ArduSimple
Two Septentrio modules are being integrated into ArduSimple’s new evaluation kits — the mosaic-X5 GNSS module and the mosaic-H heading module. The new kits make resilient centimeter-level positioning easily accessible for testing and prototyping. ArduSimple’s kits provide triple-band real-time kinematic (RTK) GPS/GNSS as a plug-and-play solution for the most popular development platforms such as Arduino, STM Nucleo, Raspberry Pi, Ardupilot and Nvidia Jetson. It enables developers of robotics, UAVs and autonomous systems to try out mosaic, a unique module offering the latest high-performance GNSS positioning technology.
Septentrio, septentrio.com; ArduSimple, ardusimple.com
Geospatial Data
Drones as a service
Photo: Beagle
A drone network solution offers on-demand imagery to customers in Germany at resolutions up to 50 times higher than available from commercial satellite data providers. The Beagle M drone and sensors can deliver image data at 1-cm per pixel many times faster than satellites and regardless of cloud coverage. The company’s charging hangars enable quick flights. After completing an autonomous inspection flight (up to 200 km on a single charge), the drone returns to its hangar where it charges for its next mission. The drone takes just 90 minutes to become fully charged, and can then advance to its next mission without any physical contact between operator and aircraft.
Beagle Systems, beaglesystems.com
A PNT expert suggested that my piece titled “Opposite and Complementary: eLoran is part of the solution to GNSS vulnerability” in our November 2021 issue could be augmented with information not currently available on the proposed eLoran capability. This expert also questioned my statement that eLoran “does not have any common failure modes with GNSS” and pointed to potential common threats such as from cyberattacks, physical attacks, and space weather.
Matteo Luccio
I welcome such feedback on the contents of these pages — and agree that in this case some hard questions are warranted. So, in the interest of further exploring the use of eLoran, I pose some questions, hoping that its advocates will provide answers. I know that at least some of them will not shy away from this challenge.
Please note that I wish to keep the discussion on positioning, not the easier question of timing, because that was the primary focus of my article. I also wish to address long-term outages (weeks or months), which would have a greater impact on the United States.
Some of these questions have been addressed, at least in part, in various studies and proposals, most of them now more than a decade old. So, it would be helpful to update those answers and consolidate them in the pages of this magazine.
1. Accuracy specifics. While my November article stated that eLoran would have a two-dimensional accuracy of “better than 20 meters, and in many cases, better than 10 meters,” is that RMS, 95%, or some other statistic?
2. Performance standard. GPS provides a commitment to users in a published performance standard. What specific measures of positioning accuracy, integrity and continuity would you recommend the proposed eLoran system be committed to provide (using the architecture described in the answer to Question 6)?
3. Coverage. Would you recommend this eLoran positioning performance hold for the entire United States (including Alaska, Hawaii, Puerto Rico and other territories), only for the “lower 48” states, or only parts of these 48 states?
4. Current users. By number of users, the predominant common current civil uses of GNSS for positioning are consumer devices (mostly cellphones). By contribution to the U.S. economy, the predominant uses are high-precision applications. For what fraction of these uses would eLoran positioning be adequate? Could an eLoran receiver and antenna fit in today’s consumer devices?
5. Future uses. Emerging civil uses of GPS for positioning include autonomous ground and air vehicles, navigation to space and in space, and lane-accurate car navigation. Which of these could be served by eLoran?
6. Architecture. To maintain accuracy during a prolonged GPS outage, eLoran would require reference stations to calibrate time-varying propagation errors, as well as a certain number of transmitters for good nationwide geometry and for redundancy, ensuring service even if a transmitter is attacked or is taken off-line for maintenance. What architecture would you recommend to achieve this?
7. Infrastructure cost. What would be the cost of installing the required transmitters, power supplies, reference stations, communication links and control system for the architecture described in the answer to Question 6? Can you reference a recent and independent estimate? To a ballpark figure, what cost fixed-price contract would you accept to implement it? Similarly, what would be the annual costs for operating and maintaining this infrastructure?
8. Impact. eLoran transmitters are large and high-power. Providing positioning across the United States could require building some of them from scratch or significantly reconstructing old Loran sites. What issues — such as environmental, aviation safety and security — would this raise, and how would you recommend they be addressed?
9. Receivers. Assuming all the above were achieved, it would accomplish nothing unless eLoran receivers were widely purchased, installed and used. How much would that cost? Who would pay? Should we assume that “if we build it, they will come”?
10. Alternatives. Given the widespread development of other positioning technologies over the past decade, much has changed since the earlier recommendations for eLoran. How do we know that eLoran is the right investment — or even a needed part of the solution or needed system in a system of systems — for the future of U.S. PNT?
Common threats to GNSS and eLoran could include the following:
1. Cyber attacks. Given that GPS’s OCX is said to be the most cybersecure system built by the U.S. Department of Defense, how would eLoran’s control system be even more cybersecure than OCX, to avoid a common cyber-vulnerability?
2. Physical attacks. Given concerns about possible physical attacks on GPS satellites, which move at multiple km/sec 20,000 km from Earth, would it not be easier to physically attack eLoran transmitters, which are stationary, terrestrial, in remote locations, and hundreds of feet tall and require massive power sources?
3. Space weather. GPS is potentially vulnerable to severe space weather that could damage satellites or temporarily hinder signal propagation from space to Earth. However, severe space weather could also damage the power grid upon which megawatt eLoran transmitters rely. How would eLoran service be protected from the effects of severe space weather, such as a Carrington Event?
Send me your thoughts at the e-mail address below, with “eLoran” in the subject line.
RINEX 4.00 (2021) is a major revision of the format document to modernize the navigation message files to be able to accommodate the new navigation messages from all the GNSS constellations, as well as system data messages such as ionospheric corrections, Earth orientation parameters and system time offsets.
The RINEX Working Group Chair Ignacio Romero provided an explanation to the GNSS community about the new RINEX 4.00 format that explains changes from previous RINEX versions.
The new format is also described in detail on the IGS Format and Standards page. For more information on the RINEX updates and activities, visit the RINEX WG Page.
The IGS adopted RINEX 4.00 during its 59th Governing Board Meeting on Dec. 7, 2021.
The U.S. Space Force has released a graph illustrating the GPS Enterprise Roadmap. The roadmap provides timelines for all the different elements of the GPS enterprise through the end of fiscal year 2028.
The link includes proposed changes for IS-GPS-200, IS-GPS-705 and IS-GPS-800 related to RFC-467 (2021 Proposed Changes to the Public Documents), as well as updated briefing charts for the 2021 GPS Public Interface Control Working Group (ICWG).
The updated documents reflect changes discussed at the 2021 Public ICWG on Sept. 29, 2021.
John Deere has revealed a fully autonomous tractor ready for large-scale production. The machine combines Deere’s existing 8R tractor, a TruSet-enabled chisel plow, a GPS-based guidance system, and new advanced technologies.
The autonomous tractor has six pairs of stereo cameras, which enable 360-degree obstacle detection and the calculation of distance. Images captured by the cameras are passed through a deep neural network that classifies each pixel in 100 milliseconds and determines whether the machine continues to move or stops, depending on whether an obstacle is detected. The autonomous tractor continuously checks its position relative to a geofence, ensuring it operates where it is supposed to, and is within less than an inch of accuracy.
John Deere Operations Center Mobile provides access to live video, images, data and metrics on a mobile device. Using the app, farmers can swipe from left to start the machine. While the tractor is working, the farmer can leave the field to focus on other tasks, while monitoring the machine’s status.
The app allows a farmer to adjust speed, depth and more. In the event of any job quality anomalies or machine health issues, farmers will be notified remotely and can make adjustments to optimize the performance of the machine.
Unveiled at the 2022 Consumer Electronics Show in Las Vegas on Jan. 4, the autonomous tractor will be available to farmers later this year.
NextNav’s Pinnacle 911 will deliver Z-axis capabilities with floor-level accuracy for wireless 911 calls in more than 4,400 cities and towns across the United States.
NextNav has entered into an agreement with one of the nation’s largest wireless carriers, not yet named, to deliver vertical location for Enhanced 911 (E911), using NextNav’s Pinnacle 911.
Pinnacle 911 leverages the barometric sensors already available in phones, tablets and other devices to deliver “floor-level” altitude measurements that exceed the FCC mandate for 3-meter accuracy. The Pinnacle service compares device data to local conditions, subtracting the weather and other factors to leave behind a highly accurate altitude measurement.
NextNav altitude stations create a hyperlocal model of environmental conditions. The precisely surveyed, high-density network delivers “floor level” real-time altitude data nationwide.
NextNav’s dedicated, managed network makes Pinnacle available throughout metropolitan areas, providing comprehensive coverage that scales to meet a variety of use cases.
The delivery of vertical location to public safety answering points (PSAPs) nationwide will improve emergency response in the United States. It enables first responders to accurately locate wireless 911 callers in multi-story buildings, enhancing both safety and response times, and helping to save lives.
With NextNav’s Pinnacle 911 reaching more than 4,400 cities and towns in the United States, including 90% of buildings above three stories, implementation of the service will exceed the Federal Communication Commission’s (FCC) Z-axis requirement for nationwide E911.
“For over two decades, one of public safety’s key needs has been 3D geolocation information — especially floor-level vertical location,” said Ganesh Pattabiraman, CEO of NextNav. “Partnering with one of the nation’s largest wireless carriers to deliver precise, Z-axis information will not only improve geolocation information for PSAPs, but save lives by reducing emergency response times by more than 80%. This adoption of our Pinnacle technology for 911 marks a historic step forward for communities around the nation, and public safety as a whole.”
In an independent evaluation by the Cellular Telecommunications and Internet Association commissioned by the FCC, Pinnacle was able to deliver floor-level accuracy (defined as ±3 m) 94% of the time, consistently exceeding the 80% benchmark set by the FCC.
NextNav’s Pinnacle service enables applications and technologies that rely on precise altitude data across industries, including public safety, mobile apps and gaming, lone worker tracking as well as out-of-home retail experiences.
NextNav’s extensive list of existing partners and customers includes AT&T FirstNet, Intrepid Networks, 3am, TRX Systems, Qualcomm, Bosch, Unity and Unreal Engine.
Hemisphere GNSS has announced another Vega heading and positioning OEM board using the Lyra II and Aquila chipsets.
The Vega 60 GNSS board fits industry-standard 46 x 71 mm form factors with a 60-pin connector. It can be used to replace more expensive and lesser abled 60-pin boards with either single- or dual-antenna capabilities.
Hemisphere’s Lyra II and Aquila application-specific integrated circuit (ASIC) designs provide the ability to simultaneously track and process more than 1,100 channels from all GNSS constellations and signals including GPS, GLONASS, Galileo, BeiDou, QZSS, NavIC, SBAS and L-band. The ASIC technology offers Vega 60 scalable access to every modern GNSS signal available.
Cygnus interference mitigation technology is also a standard feature, providing built-in digital filtering capabilities and spectrum analysis. This provides enhanced anti-jamming as well as interference detection and mitigation.
“We are excited for the opportunity to introduce our Vega 60 board,” said Miles Ware, director of marketing at Hemisphere. “Vega 60 brings our industry-leading heading and position solutions to an OEM board footprint with very few affordable upgrade paths.”
Spirent Communications plc has chosen Navmatix s.r.o., a Czech-based company that provides cloud infrastructure for real-time data delivery, to provide cloud infrastructure for its GNSS Foresight service.
Spirent GNSS Foresight is a cloud-based service delivering real-time data on the availability and quality of GNSS signals. The solution accurately forecasts when and where GNSS positioning and navigation will be most reliable through a combination of high-definition maps and precise orbital modelling. This makes it possible to obtain a clear picture of the operating environment at a moment’s notice.
GNSS Foresight will ultimately allow unmanned vehicles, air taxis and drones to operate beyond-visual-line-of-sight (BVLOS) safely.
The GNSS Foresight service enables flight in challenging environments by calculating GNSS availability for every meter, every second, from 1-100 meters altitude, for up to three days into the future. (Image: Spirent Communications)
Navmatix will provide the cloud infrastructure required to deliver GNSS forecast data as real-time data via an API. Navmatix will be deploying full operational and developmental support, including hosting for collection and processing the GNSS forecast data through its content delivery network (CDN). The CDN allows the end user to efficiently query, comprehend and interact with the data. Navmatix will handle the foundational infrastructure of the project, a significant phase in expansion of the company as a whole.
“Spirent Communications are pioneers in GNSS test and assurance solutions, and the Spirent GNSS Foresight service expands our solutions to help autonomous systems reliably use GNSS,” said Jeremy Bennington, vic president of PNT Assurance. “Navmatix has built a framework that can deliver mission-critical services, which is also reliable and scalable. We’re excited to be partnering with Navmatix and look forward to growing Navmatix’s CDN to support the growth of Spirent GNSS Foresight solution throughout its complete lifecycle.”
Because of the amount of data generated, the architecture delivers a robust and sophisticated solution, according to Navmatix. Being entirely cloud based, it allows for continual updates and remote access. The cloud infrastructure will provide the tools necessary to deliver Spirent GNSS Foresight services to Spirent customers worldwide.
Navmatix offers managed infrastructure solutions for the operation, development and ongoing maintenance of GNSS services worldwide.
Esri has released ArcGIS IPS, an indoor positioning system. ArcGIS IPS adds a blue dot to indoor maps, enabling users to locate their current position inside a building in the same way GPS enables outdoor location indicators.
ArcGIS IPS is designed to enable new use cases to improve on-site experiences, workplace operations and efficiencies. It uses an alternative technology to enable real-time positioning inside buildings that unlocks a variety of use cases, the company said.
Use cases inside buildings include:
real-time localization and positioning
real-time navigation and wayfinding
live location sharing and tracking
live location tracking
location data capture and analytical insights
real-time localization and positioning.
ArcGIS IPS is available for users of ArcGIS Indoors, an indoor mapping system for smart building management, and ArcGIS Runtime SDKs, which enables the indoor positioning capability in custom-built apps.
Image: Esri
ArcGIS IPS comes with the mobile ArcGIS IPS Setup app, which allows collection of radio signals from Bluetooth Low Energy (BLE) beacons inside buildings to enable an indoor positioning system. It can make use of an existing or new beacon infrastructure and is vendor agnostic.
ArcGIS IPS geoprocessing tools are also included to set up and author an IPS environment in ArcGIS Pro.
Users can navigate to specific points of interest — places, assets or people — in real time. This requires an existing app based on ArcGIS Runtime to support routable networks. ArcGIS Indoors can also display the route to a destination.
Radio altimeters are critical in aircraft landing systems. (Getty image). (Photo: guvendemir/E+/Getty Images)
As most GNSS industry insiders already know, the Federal Communications Commission (FCC) has licensed adjacent GNSS L1 protection frequencies to Ligado Networks (formerly Lightsquared) for its nationwide 4G-LTE network.
Many objections emerged as expected this second time around from government agencies, industries and U.S. forces — yet the roll-out is still underway, pending actual interference occurring. This all in an attempt to find communications bandwidth for many emerging commercial radio applications.
Now, as 5G C-Band 3.7–3.98 GHz wireless phone networks begin their FCC approved roll-out, the Federal Aviation Administration (FAA) has apparently lodged an unanticipated objection on the grounds that cross-interference could compromise aircraft radar altimeter and wireless communications that operate at 4.2 to 4.4 GHz in the C-band.
While 5G wireless has already been operating in many parts of the world without reports of interference with aircraft systems, the FAA appears to be taking a more conservative approach to how aviation in the United States should co-exist with the new 5G phone wireless system. The FAA has proposed imposing an exclusion zone around airports for 5G wireless networks — which apparently have already been operating with reduced power in these areas — until cooperative operation has been proven.
Now along comes a new C-band wireless network (SkyLink) aimed at providing high-integrity unmanned aircraft systems (UAS) command and control (C2). The SkyLink company uAvionix has also developed a C-band Control & Non-Payload Communications (CNPC) radio for UAS applications.
Together with Thales, uAvionics recently tested its radio with its SkyLink radio network. The network has been qualified in accordance with the RTCA DO-377 standard for a network management system that monitors network and radio link health, and the radio has been developed to the draft FAA Technical Standard Order (TSO) C-213A to support critical UAS operations.
The network uses new DO-362A-compliant SkyLink C-band radios, integrates certifiable aviation-grade hardware and software, uses frequency agility, and provides critical fault monitoring and control capability. The objective is to obviate the loss of the C2 link with the vehicle, and thereby enable beyond-visual-line-of-sight (BVLOS) operations without an FAA waiver.
It’s unclear whether the emergence of the C-band network — approved by both the FAA and FCC — will play a role in the current phone network interoperability issue. However, uAvionix reports that several sites in the United States and offshore are either rolling out C-band SkyLink networks or evaluating doing so.
North Dakota already has an ISM-band SkyLink network at its UAS test site that will shortly transition to C-band.
The Choctaw Nation in Oklahoma under an FAA program seeks to enable BVLOS operations through a C-band C2 network.
New Mexico State University will use a Skylink C2 network around Las Cruces airport for small UAS (sUAS) operations and testing to overcome anticipated interference from nearby Air Force and Space Force operations.
The Tillamook UAS test range in Oregon has already installed the first ground site of a SkyLink network.
The University of Alaska at the Fairbanks UAS test site will use uAvionics radios for testing large, heavy UAS operations.
In Canada near the Jonesburg airport, a Skylink C2 network will support the safety case for BVLOS pipeline inspection operations for the oil industry.
While many of these new networks are not yet fully online, the use of frequency hopping, safety-monitored C-band, and certifiable transmissions for UAS command and control appears to be moving forward rapidly. Because the FAA is supporting this testing phase, it seems inevitable that large-scale C-band network rollout for UAS C2 will happen eventually.
5G phone networks, wireless UAS command and control, and aircraft safety systems essential for landing will need to find a way to co-exist and provide reliable, sustained service to their respective customer bases. Look for much more to develop in this ongoing tussle between industry groups and agencies who appear to have little in common, other than grudgingly sharing a crowded radio spectrum.
Galileo Second Generation Batch#1A satellites. (Image: ESA).
Successful European Cooperation
Galileo is Europe’s civil global satellite navigation constellation and a major success, being the world’s most precise satnav system and offering meter-scale accuracy to more than two billion users around the globe.
The signature of the Financial Framework Partnership Agreement (FFPA) on June 22, 2021, further strengthened effective cooperation between the European Commission (EC), the European Union Agency for the Space Program (EUSPA), and the European Space Agency (ESA) — key to successfully achieving a crucial EU Space Program component like Galileo in the current EU Multi Financial Framework (2021–2028).
The EC is the program manager, with EUSPA acting as the exploitation manager and ESA as the system development prime.
Stable Service Performance
Galileo continues to deliver excellent service performance every month in a safe, secure and seamless manner. Delivery of Galileo services is managed by EUSPA, as the Galileo service provider, with industrial partner SpaceOpal, the Galileo service operator prime contractor. The performance of Galileo services is independently monitored by the Galileo Reference Center (GRC) and regularly published on the GNSS Service Center (GSC) web portal at www.gsc-europa.eu — both agencies were developed by GMV. The security of the Galileo System is monitored by the Galileo Security Monitoring Centers (GSMC), operated by EUSPA.
With 22 satellites in service, the open service is already delivering more than 99% availability of PDOP <= 6 worldwide. This, together with the excellent ranging accuracy, suggests that most Galileo dual-frequency users are typically experiencing positioning accuracy in the order of only 2 to 3 meters.
Timing users also continue to receive accurate (in the order of 5 ns) access to Galileo System Time, which they can trace to Universal Coordinated Time (UTC) through the corresponding offset parameters transmitted by the satellites.
The SAR/Galileo service, contributing to COSPAS/SARSAT, continues to deliver both the Forward Link Service (FLS) and the Return Link Service (RLS) with more than 99% availability, allowing users in distress not only to issue an alert and be located within a few minutes, but also be notified that the alert was successfully processed and rescue is on the way. The SAR/Galileo control center is located in Toulouse (France) and operated by CNES under the authority of EUSPA. The excellent performance of the service has been demonstrated both through several rescue exercises and real-life emergencies.
Performance of Galileo positioning services. (Credit: EUSPA)
Performance of Galileo positioning services. (Credit: EUSPA)
Galileo Launch 11
Soyuz launcher VS-26 lifted off from French Guiana with the first pair of Galileo Batch 3 satellites on Dec. 5, 2021, at 01:19 CET. This marks the 11th Galileo launch of operational satellites in 10 years: a decade of hard work by Europe’s Galileo partners and European industry. With these satellites, the robustness of the constellation has increased, guaranteeing a higher level of service.
Thanks to an upgrade of the Ground Control Segment, the Launch and Early Orbit Phase has been for the first time conducted directly from the Galileo Control Center, rather than requiring an external mission control site. This version of the ground segment increases overall reliability and cybersecurity and opens the way to significant expansion of the Galileo constellation, allowing command and control of up to 38 satellites. The development has been performed by an industrial consortium led by GMV, harnessing state-of-the-art technology using the latest solutions on the market.
Galileo launch 11 from Europe’s spaceport in French Guyana. (Photo: ESA)
On Route to Full Operational Capability
This year will pave the way toward Full Operational Capability of Galileo services.
Industrial prime contractor OHB Systems has nearly completed production of the additional 10 recurrent satellites belonging to Galileo Batch 3. Six of them are undergoing final acceptance testing at the ESA satellite test center, and the other four are under integration at the satellite prime facilities.
Preparation for Launch 12 has already started, with the satellites’ acceptance for a launch date planned in the first months of 2022, followed by Launch 13 in autumn. This is leading toward completion of the Galileo constellation, providing an increased availability of the Galileo signal in space for both GNSS and search-and-rescue users.
Performance of Galileo timing and search-and-rescue services. (Credit: EUSPA)
Performance of Galileo timing and search-and-rescue services. (Credit: EUSPA)
From 2023 onward, the remaining Batch 3 satellites will be launched with the new Ariane 62 launch vehicle, a variant of Ariane 6 with two strap-on solid boosters. The launcher is undergoing the final stages of development, led by prime contractor ArianeGroup.
The Galileo Ground Mission Segment will undergo a complete technological refresh, including hardware virtualization and porting of several million lines of code, performed by an industrial consortium led by Thales France. A series of improvements will be introduced to increase system resilience, including an extended mode of operation to improve service continuity and robustness.
Cybersecurity monitoring of all the ground assets will be introduced as an overlay to the current ground infrastructure. The upgrade will undergo a rigorous level of qualification testing followed by worldwide deployment in a seamless way in both Galileo control centers, in both Galileo security monitoring centers, and at all remote locations without affecting continuity of service.
The service facilities that contribute to the delivery of Galileo services (the European GNSS Service Center, the Galileo Reference Center, and the SAR data service providers) will also evolve to support not only the transition from Initial Services to Full Operational Capability, but also the early roll-out of service evolutions. In this regard, extensive work is ongoing to deliver an exciting set of improvements, some of which are already in development or testing, to reach the users in the year to come:
Improvements of the I/NAV signal to increase robustness and time-to-first-fix, while assuring full backward compatibility with legacy receivers.
OS Navigation Message Authentication (OS-NMA) to support applications that require trust in the authenticity of the data transmitted by the Galileo satellites (a public observation campaign was launched in November 2021 to engage stakeholders and collect their feedback before moving to the initial service provision).
An initial phase of the High Accuracy Service, delivering corrections in the Galileo E6 signal and over terrestrial network to allow users to perform precise point positioning over Europe; test signals were already transmitted with promising results.
A Search and Rescue Beacon Command Service complementing the SAR Return Link, providing improved capabilities to timely locate beacons under authorized emergency situations (such as the disappearance of Flight MH370 in the Indian Ocean in 2014).
A first implementation of an Emergency Warning Service over Europe, allowing the authorized national emergency-management authorities of the EU Member States to relay alert messages through Galileo signals, which can reach target areas even in case of disrupted terrestrial communications (such as due to floods or earthquakes).
Galileo worldwide ground segment. (Credit: ESA)
Second Generation in the Making
The FFPA will bring Galileo to the next level with the development of the second generation, a further step forward with the use of many innovative technologies to guarantee the system’s unprecedented precision, robustness and flexibility.
In parallel to the completion of the first generation of Galileo, Europe has conducted in recent years preparation activities for the Second Generation (G2). Elaborating on market, user and exploitation needs collected by EUSPA, ESA identified a number of system evolution scenarios, which were discussed among relevant EU stakeholders to select the second-generation mission and services baseline to build the system infrastructure.
The evolution of Galileo capabilities will not only provide better services through advanced technical solutions identified by ESA, but will also ensure continuity of service and backward compatibility for
first-generation legacy users.
Two parallel contracts to develop and manufacture each of the six Galileo Second Generation Batch#1 satellites were kicked off in the first half of 2021 with Thales Alenia Space (Italy) and Airbus Defence & Space (Germany). The new G2 satellites will be constructed on a short time scale, with their first launch via Ariane-62 expected in less than four years, allowing them to commence operations in space as soon as possible. Both contracts have already undergone preliminary design reviews.
Development of the G2 satellites is supported by the Galileo Payload Test Bed, which provides an early proof-of-concept of the advanced G2 payload architecture. These satellites will provide, among others, the following key innovations:
Reconfigurable fully digital navigation payload.
Point-to-point connection between satellites by Inter-Satellite-Link for command and control and ranging functionalities.
Electric propulsion for orbit-raising capabilities.
Advanced jamming and spoofing protection mechanisms to safeguard Galileo signals.
System and Ground Segment definition studies, together with the associated technology pre-developments, have been performed, leading to the definition of the preliminary design and technical requirement baseline for the G2 system, a project involving most of Europe’s space industrial partners.
The G2 In-Orbit Validation Ground Segment and System Test Bed have been defined and relevant procurement procedures are ongoing, with these objectives:
G2 Batch#1 satellites launch and early orbit phase, in-orbit testing and enhanced legacy services provision.
G2 new capabilities in-orbit validation, including prototyping and validation of all the novel technologies that can exploit the full capabilities of the G2 Batch#1 satellites.
Galileo Second Generation Batch#1B satellites. (Image: ESA).
Definition activities for the G2 Initial Orbit Capability (IOC) are progressing well and are expected to converge in the first half of 2022, in order to establish the future roadmap for new G2 services provision in the years to come.
2022 will be a key year for the evolution of Galileo Second Generation activities, through the consolidation of the first batch of G2 satellite design and development activities and the start of development of associated G2G IOV Ground Segment and System Test Beds.
A bright future awaits Galileo, both through the completion of its Final Operational Capability and the start of evolution towards Galileo Second Generation.
Guerric Pont is Galileo Exploitation Program manager for the European Union Agency for the Space Program (EUSPA).
Marco Falcone is Galileo First Generation Project manager for the European Space Agency (ESA).
Miguel Manteiga Bautista is Galileo Second Generation Project manager for the European Space Agency (ESA).
