Hexagon│NovAtel’s OEM7 GNSS receivers have successfully tracked Xona Space Systems PULSAR signals generated by a simulator from Spirent Communications. This test proved NovAtel GNSS receivers can track a Spirent simulated L-band signal identical to the PULSAR signal broadcast by Xona’s low-Earth orbit (LEO) satellites.
The Xona LEO signals will complement GNSS, improving resiliency, security, and precision for positioning, navigation and timing (PNT).
“Using Spirent’s simulated PULSAR signal, we have successfully tested our receiver’s capability to track the L-band signal planned to be broadcast from Xona’s LEO satellites,” Sandy Kennedy, VP of innovation at Hexagon’s Autonomy and Positioning division, said. “The OEM7 is a powerful platform, designed for both resiliency and flexibility; it is exciting to test our forethought by trialing this new signal type.”
It has been a wild decade, with so many players in the autonomous vehicle (AV) market, all striving for a leg up. Until the dominant design of present AV stacks emerged, there was no small amount of experimentation and less-than-successful alternate approaches. For instance, there was one big-name player that initially sought to create an AV solution without GNSS. Reality set in, and they soon embraced GNSS as an essential component.
Gordon Heidinger, segment manager, automotive and safety critical systems at Hexagon’s Autonomy and Positioning division, has had a front-row seat from which to observe, and contribute to the evolution of AV.
“I’ve been in the automotive industry for 20 years, all the way from OEMs like Chrysler to tier ones like Harman,” Heidinger said. “I’ve worked on the engineering side, on the project management side, and have now joined Hexagon | NovAtel to help further their involvement in the automotive industry. NovAtel was there for aviation 20 years ago, helping develop systems for planes to take off and land autonomously — we have a deep bench when it comes to applying such expertise for vehicular autonomy.”
NovAtel has long provided GNSS and IMU products and solutions, as well as real-time positioning services. Each are key elements of AV sensor stacks and overall autonomy solutions. Parent company Hexagon has multiple divisions contributing to intelligent transportation — on both the front end and back end.
The Front End
AV systems require highly reliable and smart sensor stacks that typically include cameras, radar, lidar and sonic sensors; these provide the relative positioning for advanced driver assistance systems (ADAS), which are becoming commonplace for newer vehicles. There are also implementations that include GNSS/IMU for navigation and lane keeping.
“Lane keeping is possible to a limited degree with combinations of the other sensors; however, you need GNSS to let you know where you truly are for autonomous driving,” Heidinger said. “Are you on the right freeway lane in Ottawa, or is this an exit ramp? This was a big problem with today’s simple single frequency solution; a car can assume highway speeds on an exit ramp, not realizing it was an exit ramp.”
Only with the absolute precise positioning that GNSS provides, and a high-definition map, level 4 autonomy — and potentially level 5 someday — could be achieved. With current sensor stacks, when the car is moving, it can reliably detect the other cars moving in its vicinity. Furthermore, vehicle-to-vehicle (V2V) solutions are being developed and tested, which enable a vehicle to share data about where it is going, its speed and acceleration, and its current location. We may remain far from full autonomy until such solutions are broadly deployed, however we will see some of the vehicle-to-everything (V2X) solutions sooner than later.
Various developers and departments of transportation around the world are testing short range V2X communication systems.
“We would need real-time construction zone updates,” Heidinger said. “It would be tough to do lane keeping if a construction site closes or diverts lanes during the course of a day. Or if cameras detect crashes, or blocked lanes, this will need to be broadcast immediately and continuously in real-time.”
A representative example of a production high precision positioning system was demonstrated at the recent Consumer Electronics Show 2023 (CES 2023). ZF Friedrichshafen AG (ZF) has developed ProConnect — a dedicated short-range communication (DSRC) solution that enables positioning and communication for use in applications with roadside infrastructure, such as traffic lights. It can be scaled to include other over-the-air alerts that could include first responder vehicle proximity and construction site status. At CES, the GNSS positioning was demonstrated with an autonomous vehicle platform from Hexagon.
“The precise map and the real-time updates from V2V and V2X systems all need precise absolute positions to relate objects to each other,” Heidinger stated. The question then becomes “…how reliable and trustworthy is that solution”?
There are international automotive-grade requirements such as the ISO 26262 standard for electrical/electronic systems, and automotive safety integrity levels. For instance, ASIL-B(D), and cybersecurity standard ISO/SAE 21434. The latter provides protection against external access without authorization.
“The level of reliability required is extremely high,” Heidinger said. “After all, these are human lives, in metal boxes hurtling along at highways speeds. There are ASIL standards that call for a probability of 10-8, or 1 in 100 million, in an hour that the system is wrong. These levels of reliability need to apply to electronic components, communications, and the availability of the GNSS positioning solution to really automate any type of vehicles. You’ll encounter similar AV standard references to five-nines, or 99.999%.”
Positioning Services
Heidinger explained that for most aspects of autonomy, GNSS can be “good enough”, even just to a foot. However, uncorrected, GNSS can never meet even those needs — achieving an accuracy of a few meters at best. Then there is the matter of reliability. Augmentations like real-time kinematics (RTK) and precise point positioning (PPP) apply broadcast “correctors” that can yield centimeter positions. RTK is not practical for broad areas or highway and road networks as it requires dense infrastructure and two-way communication with the vehicle, which can introduce security challenges.
Solutions for autonomy are typically PPP. While there are many applications of PPP that use clock, orbit and ionospheric model data broadcast from geostationary L-band satellites, for applications such as surveying, mapping, maritime and agriculture, this would not meet the reliability requirements for AV. The Achilles heel of broadcast PPP is that the satellites are usually limited in number and positioned over the equator; the vehicle can often lose sight of these. Instead, PPP services, such as that provided by NovAtel and others, are tapped by vehicles via mobile internet connections; this means cellular networks. While cellular services can often meet reliability goals, there are still vast areas of highways where availability is sparse.
The other challenge for PPP is the convergence time needed to get reliable sub-foot precision.
“No one wants to wait five minutes or more for it to converge,” Heidinger said. “By processing data from semi-dense networks of reference receivers, our PPP can converge rapidly enough to be ready to roll as soon as you start driving.”
The Back End
A free-for-all of autonomy is not going to happen on highways and roads that are not precisely mapped and kept up to date.
“There are visions of crowd sourcing map updates from the sensors in cars,” Heidinger said.
Crowd-sourced data is not systematic enough, though, and could be inconsistent. After all, there are privacy considerations, and how many vehicle owners would be willing enough to participate?
There are numerous mapping and imaging “buggies” plying road and highway networks on an ongoing basis; this could provide a base layer. But how precise? The specific applications these mapping buggies support may not need high precision. And operators may not be willing to invest in high precision/accuracy. The precision of the 3D maps would need to be higher than the target range of the AV systems. The technology exists and is broadly used for various applications in the form of centimeter precision 3D mobile mapping — at highway speeds. Such systems with lidar scanners, cameras, and positioning solutions can include GNSS, IMU, wheel speed encoders, and SLAM lidar for enhanced position stabilization. An example is the Pegasus TRK from Hexagon | Leica Geosystems.
GNSS is the key component — the provider of precise absolute positioning. When people drive, they are the sensor stack, and they are (mostly) aware of the context of where they are and can see and hear what is going on around them. Before we can hand over the driving duties to machines, and fully accept any autonomous driving technology, it will not only need to be as smart and aware as humans, but much better and more aware than humans. Autonomy sensor stacks can tell a car what it is doing, and what other things are doing in its immediate vicinity, but without a precise map, and knowing precisely where it is in real-time, a car would be still tip-toeing around in a fog of uncertainty.
Q & A with Peter Soar, Business Development Manager, Military and Defense, Hexagon | NovAtel. Read more from this cover story here.
U.S. Army m2A3 Bradley Fighting Vehicle prepares for a platoon live-fire exercise at Pabradė Training Area, Lithuania, Oct. 13, 2022. It has a GAJT anti-jamming antenna. (Image: U.S. Army National Guard photo by Sgt. Lianne M. Hirano)
What have been the advances since you began deliveries of the GAJT-710ML?
The original signal plan for GAJT-710ML was GPS L1 and GPS L2 only, with specific capability to use civil, P(Y) and M-Codes. GAJT-710ML as delivered in 2019 addressed GPS L1, Galileo E1, QZSS L1, GPS L2, QZSS L2. The version delivered provides situational awareness by jammer power level – by automatic gain control (AGC), as well as jammer direction-finding to the most powerful jamming signal. We are in the process of improving GAJT-710ML to be able to give simultaneous directions to multiple jammers.
Meanwhile, deployment of GAJT-410ML has started. This is a 4-element version of the same technology as GAJT-710ML but for smaller platforms. By using an internal junction box, the user can install this GAJT with just one small RF cable penetrating the vehicle armor. The latest GAJT version is GAJT-AE2. This UK-built board-level product is also able to use the strong L5 signals.
We have also launched the Robust Dual Antenna Receiver (RoDAR). Our engineers put an anti-jam algorithm directly on our OEM7 dual-antenna receivers (OEM718D and OEM7720).This is for the very small platforms that cannot carry a full GAJT. It only provides one null (as it has two antennas) although it does so simultaneously on L1 and L5 and related GNSS signals.
NovAtel’s GAJT are commercial off-the-shelf (COTS) products. How does that help you with exports?
GAJT products are built in Canada (mainly) and the UK and are subject from source to the Controlled Goods Program of Canada and UK Export controls respectively, but are not subject to U.S. International Traffic in Arms Regulations (ITAR) until shipped to the United States. RoDAR is based on OEM7 receivers which are free from export controls and because only one null is created per frequency, the RoDAR configuration is also free from export controls.
Once goods controlled by Canada or the UK land in the United States, or are incorporated into an already ITAR controlled system, then they become subject to the ITAR. Being COTS helps with export classifications because GAJT is dual-use. For example, it is used in oil and gas exploration. One of the ways that we work with the U.S. Department of Defense and other departments is via Hexagon U.S. Federal, which is a U.S.-proxied organization that can operate at classification levels beyond what other Hexagon units can.
Has the form factor remained essentially the same, and will it remain the same, while you upgrade the electronics?
The GAJT-710ML form-factor remains unchanged. This is important because the installation schemes take time to design and the customer likes continuity in the area. We intend for follow-on products —which will naturally be better performing, lower volume and lower power — to have an optional interface that will allow mounting on existing installation schemes. GAJT-410ML and the other products are smaller.
Hexagon says that its anti-jam technology increasingly emphasizes protecting GPS signals against Cyber Electromagnetic Activities (CEMA) from the advanced armed forces of nations. What are some examples and in what direction is anti-jam technology evolving?
Most conflicts of the previous generation were “asymmetric” in terms of the military technology deployed by each side. Now we see more conflicts between advanced armed forces which are more symmetric and expect that to continue. Anti-Jam technology is evolving to encompass all the GNSS signals and other PNT sensors that are being used by allied defense forces. This includes added GPS signals (beyond L1 and L2) as well as GNSS, L-Band corrections, SBAS and other emerging PNT signals. One task for us is to discern users’ requirements. Even within NATO there are different national policies as to which signals and sensors are essential/desirable/not to be used.
On the operations floor of the GPS Master Control Station at Schriever Space Force Base in Colorado, Luccio looks at feeds from a worldwide network of monitor stations and ground antennas. (Image: U.S. Space Force photo by Dennis Rogers)
The young operators on duty at the GPS Master Control Station, at Schriever Space Force Base in Colorado, receive feeds from a worldwide network of monitor stations and ground antennas, monitor the GPS satellites, and send them commands as needed. This month’s cover story features excerpts of an interview with their commander, Lt. Col. Robert O. Wray, about the training and duties of his team members, the challenges they face, and what brought him to his current assignment.
Hexagon | NovAtel has released the 7.09.00 firmware with a precise timing protocol (PTP) feature, enabling users to synchronize accurate time from GNSS with other devices and sensors on a shared network.
The 7.09.00 firmware’s PTP feature brings stable timing to a user’s other sensor systems connected through a local network to best support positioning, navigation and timing (PNT) and automotive and autonomous applications.
The firmware includes SPAN GNSS+INS technology improvements — including a secondary INS solution for built-in redundancy and reliability in challenging conditions. The enhancements are available on all OEM7 cards and enclosures, including all PwrPak7 and CPT7 enclosures variants.
The 7.09.00 firmware also features improvements to the time to first fix, a secondary SPAN solution for a more accurate and reliable GNSS+INS output and more.
The 7.09.00 firmware is not for precision agriculture applications and is not supported on NovAtel’s SMART antenna products.
One of a small army of PhytoPatholoBots (PPB) developed by Cornell University and deployed to four grape breeding programs across the United States. These autonomous robots will roll through vineyards, using computer vision to gather data on the physiological state of each grapevine. They use a NovAtel SMART antenna. (Image: Allison Usavage / Cornell University)
One GNSS receiver widely used in autonomous ground vehicles is Hexagon | NovAtel’s SMART7 antenna. Matteo Luccio, GPS World’s editor-in-chief, discussed the product and its applications with Haley Lawrance, Senior Positioning Product Manager, Agriculture for Hexagon | NovAtel.
Luccio: “How do you differentiate your SMART antennas from your other GNSS receivers?”
Lawrance: “The reason why the SMART antenna portfolio has been so attractive within the agriculture market and to our autonomy customers specifically, has been the ease of integration and the high performance it provides. GNSS positioning is just one part of an autonomous system, and the autonomous integrators don’t necessarily have the volume of machines out of the gate that would justify the development time for them to integrate the OEM components.
With NovAtel’s SMART antennas, they only need to consider the single cable harness that will run power and communications to and from the receiver – and a single mount point on the vehicle. The SMART antennas offer a waterproof and rugged enclosure, designed to withstand the demanding environments typical for agriculture – and help accelerate our customers’ time to market.”
Luccio: “Is there some standard, as there is for cars, that enables developers of autonomous systems to easily plug your system into theirs?”
Lawrance: “We support a variety of communication protocols – serial, CAN, Ethernet, and Wi-Fi. For autonomy, Ethernet tends to be the most common option for communication with the GNSS receiver – especially when using features that require more bandwidth, such as our SPAN GNSS+INS sensor fusion solution that leverages an inertial measurement unit.
NovAtel’s_OEM7_driver, built for the Robot Operating System (ROS), is a great option because it makes it even quicker for them to integrate and allows the receiver to essentially plug-and-play into the ROS environment with minimal development. For CAN, we support both J1939 Transport and Extended Transport Protocol and NMEA 2000 if they would like to communicate onto an existing bus they are using on the vehicle.”
Luccio: “What about the ease of integration on the software side?”
Lawrance: “We have a very large library of proprietary NovAtel-formatted logs that are available in binary and ASCII, which provide flexibility and allow customers to customize a unique set of logs that provide the data they are interested in. This could be anything from information on which satellites are being used in the solution, to the roll and pitch of the vehicle, or status information from the receiver. NovAtel receivers also output in standard formats, such as NMEA 2000 and NMEA 0183, that consolidate the data that they are most likely to need, such as position, velocity, and quality indicators.”
Luccio: “What markets do your SMART antennas target?”
Lawrance: “Broadly speaking, the SMART antenna product line was designed specifically for agriculture use cases and environments. Customers include agriculture OEMs, aftermarket integrators that develop retrofit precision ag solutions, and autonomous solution providers.
Within that product line, we have SMART7 and SMART2, with different performance options that allows us to scale the best product solution for each application. For high-performance semi-autonomous or autonomous applications that need centimetre-level accuracy – even in highly variable terrain and challenging GNSS-obstructed environments, SMART7 is the best fit – together with SPAN GNSS+INS and TerraStar-C PRO Correction Services or RTK.
For additional positioning redundancy on an autonomous vehicle, SMART2 can be used together with SMART7 – meaning there are two different, independent GNSS hardware, software, and positioning solutions running in parallel. This allows autonomous machinery manufacturers to utilize both positioning solutions in parallel for an additional layer of protection.”
Inertial Labs has released a remote sensing payload instrument. The Resepi Hesai XT32 laser is designed for accurate remote-sensing applications. The Resepi laser can be used with commercially available lidar scanners, including Velodyne, Quanergy, Ouster, RIEGL, LIVOX and Hesai, as well as with UAVs.
Resepi is completely modular, so users have full control for customization. The remote sensing device uses a GPS-aided inertial navigation system with NovAtel RTK/PPK single- or dual-antenna GNSS receiver, integrated with a Linux-based processing platform. It also comes with a 2 TB USB memory drive and has an embedded Wi-Fi cellular modem.
Resepi has 3-5 cm point-cloud accuracy and can reach heights of more than 200 m above ground level. It is compatible with most UAV models; however, it is typically used with DJI M300, DJI M210 or DJI M600 models.
The device is suitable for scanning and mapping, precision agriculture with lidar, simultaneous localization and mapping (SLAM) algorithm development, utility inspection and construction site monitoring. Resepi-supported software includes Hexagon NovAtel, PCPainter and PCMaster.
JCB has launched its Fastrac iCON tractor to the public featuring the Hexagon | NovAtel’s SMART7 GNSS receiver. The tractor also offers optional TerraStar Correction Services driving the iCONNECT precision technology package and offering operators an easy-to-use customizable experience.
The SMART7-I included in the new Fastrac iCON tractor is a rugged, waterproof, all-in-one GNSS smart antenna designed and tested specifically for the agriculture industry.
Connectivity is with Wi-Fi and Ethernet. TerraStar and RTK corrections provide the centimeter-level accuracy required for any farming application. With multi-constellation and multi-frequency capabilities, it is a dependable solution for farms with treelines and obstructions that may impede satellite signals.
With the availability of TerraStar Correction Services, operators can have the highest accuracy and year-over-year repeatability globally. TerraStar offers fast, consistent positioning through the planting, spraying and harvest cycle with 99.999% uptime and availability.
“The iCON tractor is designed around the farmer. We wanted a GNSS solution farmers can rely on that stands up to harsh agriculture environments while providing the accuracy to support our precision technology,” said Greg Fitton, general manager, Fastrac Sales at JCB. “We chose NovAtel as our GNSS experts because of their demonstrated reputation for quality, cutting-edge technology and performance, and their willingness to adapt to our needs.”
Interview with Sara Masterson, Director, Positioning Services, Hexagon’s Autonomy & Positioning division, Hexagon | NovAtel
The accuracy of GNSS receivers continues to increase thanks to new satellites and signals, improved antennas, etc. How is that changing the role of correction services?
For sure, the accuracy of GNSS receivers and antennas is improving. However, most applications still require a higher level of accuracy than what is available from an uncorrected position even with the positioning improvements brought by new constellations and signals. GNSS corrections are still required to enable, say, lane-level accuracy, or sidewalk-block accuracy for autonomous driving or mobile phone applications and for off-road autonomy applications such as construction, mining, agriculture — these all still require centimeter-level accuracy that is enabled through GNSS correction services.
Corrections also help by improving the availability and reliability of a solution. In the future, corrections will play a key role in adding integrity to enable functionally safe solutions that are required for new applications, such as autonomous driving.
There are many options for corrections — local, regional and global, ground-based and satellite-based, public and private, etc. Which of them are generally best for which applications and conditions?
That depends very much on the user and the application. There are many new correction services in the market. Some are free, some are commercial services. Even now we see in agriculture that WAAS is sufficient for some broadacre-type applications. So, we will continue to see a range of applications, some of which will be satisfied with the level of performance from a free service and others that will be looking for the better performance and service level guarantees that come with commercial services.
If something is not working when you are using a free service, there’s no one to call. With commercial services, you get responsive customer support and you pay for higher levels of performance and service availability. In many applications, especially those that involve autonomy or safety applications, you cannot afford to have downtime, or your machine just stops working, which costs money. So, many applications are still going to be needing the performance and service level guarantee that commercial services offer.
How does TerraStar fit into this range of options? What industries and applications are you targeting?
TerraStar has a range of services that enable us to target many industries and applications. Agriculture, of course, is one of the key applications for our services and we have customers using TerraStar for mobile mapping, UAVs and new autonomy-based applications. We are also involved with some interesting Hexagon joint projects that use TerraStar corrections for mine train automation and surveying and construction.
Our entry-level TerraStar-L service is still better in performance to many of the free services or to an SBAS-type service in terms of accuracy, but it is available globally, including regions where you don’t have other options. It also provides better pass-to-pass and year-over-year repeatability, as well as very quick reconvergence time if there are any issues with GNSS outages.
Our flagship offering is the TerraStar-C PRO service. That’s where we just introduced the “RTK from The Sky” technology, bringing the performance down to converging to two and a half centimeters in three minutes. That, too, is available globally which makes it a real game changer for customers in many different applications, because they can start to look at that service as an alternative to RTK and without the added connectivity logistics that an RTK solution brings.
Our RTK assist solutions are good augmentation solutions for customers who still primarily need RTK but experience some RTK correction outages – RTK ASSIST bridges through those outages. So, we have a wide range of service offerings in the portfolio that can address the positioning needs of many applications.
Photo: Hexagon | NovAtel
Will the reasons for having a base and rover setup decrease sharply?
Use of base and rover setups is already decreasing and being replaced by both PPP and network RTK solutions. There are applications where RTK still makes sense, such as those that have very tight vertical requirements and many survey applications. Another Hexagon division, Hexagon’s Geosystems division, incorporates TerraStar correction data into their new SmartNet Global offering as a seamless service that provides both SmartNet RTK plus TerraStar for either bridging outages or independent PPP operation, depending on the project’s location and whether they’re within range of SmartNet coverage.
There will be many applications that continue to benefit from a combination of the two technologies. However, as the PPP services, like TerraStar, continue to improve by reducing convergence time and providing highly reliable solutions, users in those applications can be confident that the standalone PPP solutions meet their performance needs and bring many additional benefits such as consistent, global coverage and performance.
Is TerraStar completely receiver agnostic?
TerraStar is currently only compatible with NovAtel’s GNSS hardware. Going forward, through the work that I referenced with autonomous driving and mass-market applications, we will be providing TerraStar services in industry-standard formats, depending on the inter-operability requirements coming from those applications. We expect that there will be demand for dual sourcing of corrections and interoperability between chipsets that are used in vehicles, for example. For those applications, we will be developing TerraStar services that are compatible with hardware from other GNSS manufacturers.
Hexagon | NovAtel’s CPT7 integrates a GNSS receiver and an INS to deliver up to centimeter-level accuracy. (Photo: Hexagon | NovAtel)
We discussed mobile mapping with Bryan Leedham, product manager of enclosures and post-processing software, NovAtel, Autonomy & Positioning division, Hexagon.
How do you define mobile mapping?
It is getting broader in scope, as more folks find reasons to map the world. The key goal is to capture reality from mobile platforms to build a digital representation of reality for some large area, such as a city, a road or a factory. Most of the time, that means from a ground vehicle on public roads.
It’s also safer and faster than traditional surveying because you don’t have to stop traffic or dodge it.
Right! In an ideal world, rather than spending days setting up traditional survey equipment, you could strap some sensors on a mobile platform and gather accurate map data in minutes.
What are the key remaining technical challenges?
Picture one of Google’s or Waymo’s mapping vehicles. The first sensors that come to mind are GNSS, inertial, lidar and radar. Each of those has its own unique strengths and weaknesses. The first technical challenge that remains is to mature each of those technologies for a lower enough cost that it’s affordable.
Right now, mobile-mapping vehicles are quite expensive, especially in areas where some of these sensors will struggle more than others. To map very dense urban spaces — with underground areas, overpasses and tall buildings where GPS is challenged — you need a very strong localization system that can survive those conditions for however long it takes to drive through them. If I’m building a car to map rural Alberta, I could choose much cheaper sensors than if I were trying to map downtown Chicago every week.
On the flip side, you must deal with the massive amounts of data collected.
Yes, that is a very large challenge. Lidar data, in particular, is guilty of generating very large point clouds. It’s a balancing act. More accurate and higher resolution maps require lidar sensors with even denser point clouds. So, you need data management and sufficient processing power to get accurate results quickly.
What are the key technical challenges in sensor fusion?
Sensor fusion is how we approach the goal of mapping as accurately as possible in increasingly difficult environments. On their own, GNSS receivers struggle in obstructed areas but, when you pair them with other sensors, they become very complementary.
Lidar and cameras, for example, are quite good at measuring the distance to nearby objects and at classifying them, but they have no idea where they are relative to one another. Likewise, if you let an IMU [inertial measurement unit] sit in your car, it will no longer know its location. However, once you give it a position update, it is very good at maintaining a trajectory over a short period of time. When you combine absolute and relative localization, all the sensors play to their own strengths.
What is NovAtel’s SPAN software?
It stands for synchronous position, attitude and navigation. It is the sensor-fusion software that combines the GNSS, inertial and whatever other sensors. It is based on core NovAtel GNSS receiver software. We can use NovAtel receivers in combination with IMUs from a wide range of manufacturers and, in the future, hopefully, other sensors from a variety of manufacturers as well.
SPAN started with blending just GNSS and inertial but we’re now researching how to bring in such things as lidar and cameras. Autonomous Stuff, another Hexagon company, works on the greater sensor fusion using SPAN as well.
The launch of Xona’s test satellite begins a new era of innovation in assured PNT, with NovAtel receivers demonstrating early support of Xona’s signals
Hexagon | NovAtel has signed a memorandum of understanding with Xona Space Systems to collaborate in the positioning, navigation and timing (PNT) development of Xona’s new low-Earth orbit (LEO) constellation.
LEO constellations offer a new avenue of assuring PNT by providing stronger signals with satellites closer to Earth and improved positioning accuracy with rapidly changing geometry, NovAtel explained. Additional constellations and a larger number of available satellites improve visibility in cases where parts of the sky are obstructed by buildings and other obstacles.
Also, as the threat of unintentional or malicious jamming and spoofing increases, it becomes important to consider alternative sources of PNT and resiliency methods, the companies said.
“Precise and robust PNT forms the foundation for safe operation of modern applications such as automotive and autonomy,” said Brian Manning, CEO of Xona. “We are thrilled to be collaborating with NovAtel to demonstrate the benefits that our combined technologies can bring to these markets and many more.”
Xona’s new constellation will transmit encrypted signals on two frequencies, both offering authentication, further building new levels of resilience against malicious interference. NovAtel is an early adopter of Xona’s signals and an industry leader in resilient assured PNT.
“This agreement accelerates the future of alternative PNT,” said Sandy Kennedy, vice president of innovation at Hexagon’s Autonomy & Positioning division. “Our collaboration will demonstrate the complete assured PNT ecosystem that Xona has envisioned, and of which NovAtel is very excited to be part.”
Xona and NovAtel will be presenting innovations in assured PNT and the future of GNSS at the Autonomy & Positioning Reality Summit during HxGN LIVE Global in Las Vegas, June 20-23.
Hexagon | NovAtel’s GAJT-710ML installed on a U.S. Army vehicle. Photo: U.S. Army Futures Command
We asked Dean Kemp, Ph.D., director of Marketing, Aerospace and Defense for Hexagon’s Autonomy & Positioning division, a few questions.
How do jamming and spoofing threats change?
Jamming and spoofing methods change as new interference-causing technologies become available. As such, it’s vital for us to continuously evaluate potential sources of threats and provide the highest possible level of resiliency to interference in our solutions.
Have new threats emerged in the past six weeks in connection with Russia’s invasion of Ukraine?
Evidence is emerging that electronic-warfare systems capable of high-power jamming and spoofing across wide areas are being used within Ukraine. Fortunately, there have been no known impacts on allied forces. However, knowing that the technology is in place and in use highlights the importance of assured positioning, navigation and timing (APNT) and our contribution to building resiliency in allied forces’ equipment against the potentially destabilizing effects of jamming and spoofing.
How do you define APNT?
We use APNT to describe measurements that are always accurate, available and reliable. Our anti-jamming, anti-spoofing and other resilience-building capabilities provide trusted and available PNT information at the level of accuracy requested.
When did you introduce GPS Anti-Jam Technology (GAJT)? How do you define it?
GAJT was introduced in 2011 and is our leading APNT solution. GAJT units are utilized worldwide across land, sea and air, with rapid deployment supported by commercial off-the-shelf solutions and short lead times. GAJT provides jamming protection of satellite-based navigation and precise timing receivers from intentional jamming and unintentional interference whatever your application. Product variants provide features to best support anti-jamming capabilities for the warfighter, national infrastructure, low-SWaP platforms and other mission-critical applications.
What are the key differences between the GAJT-710ML, the GAJT-710MS and the GAJT-410MS?
The GAJT-710 is designed for land vehicles (ML variant) and marine vessel platforms (MS variant) with up to six simultaneous nulls to protect against jamming signals and interference. The next generation of GAJT-710 includes jammer direction-finding and a silent mode to reduce its thermal signature. The GAJT-410 maintains the high levels of interference-rejection performance in the 710 but in a lower size, weight and power (SWaP) design, with three simultaneous nulls, for both land and marine variants. It also utilizes a single RF cable to provide clean power, data and protected GPS signal. The GAJT-410 enables APNT while also reducing the need for platform modifications or armor penetration.
The GAJT-AE extends jamming and interference protection to unmanned and autonomous applications. Using an external CRPA antenna, the GAJT-AE offers flexibility of integration into space-constrained platforms.
Is the GAJT-AE-N Anti-Jam Antenna receiver-agnostic?
We designed our GAJT product line to be receiver-agnostic and compatible with legacy and modern GNSS receivers. This flexibility results in GAJT being ideal for civil and military applications, including SAASM and M-code systems.
How does your GNSS Resilience and Integrity Technology (GRIT, launched in 2020 November) relate to your GAJT antennas?
GRIT is a firmware suite for our OEM7 receivers that expands their situational awareness and interference mitigation tools. GRIT includes our Interference Toolkit (ITK) along with spoofing detection to identify when your GNSS signal may be under threat. It also empowers the user to develop interference location algorithms through time-tagged snapshots of data samples to characterize the RF environment around your operations. GRIT, alongside GAJT, forms the foundation of our APNT strategy in providing accurate and always-available PNT.
Do you have any recent contracts with the U.S. Department of Defense or the militaries of other NATO countries to supply GAJT antennas?
Our GAJT product portfolio has been sold in large quantities to military and civil organizations for many years, successfully proving itself in the field. In 2020, we achieved a milestone of more than several thousand units shipped worldwide, making it one of Hexagon | NovAtel’s more successful years.
