One of the top dogs in the mil-spec UAV world, General Atomics Aeronautical Systems Inc. (GA-ASI) has developed and built several jet-powered demonstration UAVs known as the MQ-20 Avenger, which is currently being used to test out new U.S. Navy communications systems. Derived from the MQ-1 Predator and MQ-9 Reaper, the Avenger is equipped with a Pratt & Whitney turbofan jet engine, allowing it to reach speeds of around 400 Knots at an altitude of up to 50,000 ft.
Predator C Avenger UAV. (Photo: GA-ASI)
After extensive testing since its first flight in April 2009, a larger extended range (ER) version began test flights in 2016. The extended range version has longer wings and an increased fuel capacity with a range of 2,000 miles and an endurance of 20 hours. Avenger has several stealth features, including an S-shaped engine exhaust and an internal weapons bay for precision weapons and sensor packages, similar to the F-22 Raptor and F-35 Lightning front-line fighters. Another recent project saw F-35 technologies passed onto the same jet-powered UAV platform.
The recent Navy communications trials were used to prove the new space-based comms capability and to remotely adjust Avenger’s autonomous internal navigation system while in flight. The aircraft has been designed for long-range, high altitude, speedy, autonomous penetration of enemy areas and this latest capability allows operations where the run-in-to-target phase can be redirected in the very last minutes of an attack. Enemy radar tracking and defenses might, therefore, be misaligned at a crucial phase of an incoming drone alarm without sufficient time to re-align and protect the actual target.
Space-based communications, in this case, used signals via the Proliferated low-Earth orbit (LEO) system of satellites, which is reportedly a mil-spec LEO constellation of communications. satellites — somewhat related to the orbits of the Space-X commercial Starlink LEO internet satellite system.
While we are in the military domain, a recently displayed Chinese development is being claimed to be a jet-powered ‘mothership’ UAV. The concept is that the carrier aircraft travels longer distances and releases a swarm of short-range drones when within range of their target(s) — a possible mock-up of such a vehicle was shown before a recent Chinese airshow.
Jiu Tian mothership UAV mock-up. (Photo: Chinese internet)
The center section of the UAV appears to be detachable or has large opening doors – the Chinese and English inscriptions on it imply that it is a module for carrying drones. There have been other reports that Chinese military thinking includes the deployment of large swarms of drones to attack multiple targets simultaneously. However, The Jiu Tian UAV does not come with a stealthy design.
In light of the recent competition between the U.S. and China, an article about the new U.S. Air Force B-21 stealth bomber has been published. The article suggests that, given the F-35 stealth fighter-bomber’s exceptional stealth capabilities and its ability to carry and release multiple weapons from an internal bay, the B-21 may already face obsolescence.
So then, why not re-purpose the B-21 to be a drone-carrying mothership that could, while undetected, penetrate enemy defenses to release swarms of U.S. attack drones?
B-21 next generation Stealth bomber. (Photo: U.S. Air Force)
Currently, a part of the U.S. three-pronged nuclear delivery deterrents alongside submarines and ballistic missiles, the Air Force believes that the role of the existing B-2 Spirit bomber is not obsolete, and the B-21 should become operational as planned in the 2030s with its new stealth and suite of high-end technology sensors and control systems.
The concept of a Chinese “mothership” is designed to transport drone swarms close to targets before launching them. Additionally, there may be a stealthy response from the US, utilizing low-Earth orbit (LEO) satellites for space-based communications to adjust the routing of autonomous drones. This approach raises the question of whether it could be used to deceive drone defenses during the terminal phase of an attack. These solutions are complex but could significantly enhance the effectiveness of future military drone operations.
ANELLO Photonics has successfully closed its Series B funding round to advance the development of its silicon photonic optical gyroscope (SiPhOG) technology for navigation in GPS-denied environments.
This funding round was co-led by Lockheed Martin, Catapult Ventures and One Madison Group, with participation from several other investors, including New Legacy, Build Collective, Trousdale Ventures, In-Q-Tel (IQT), K2 Access Fund, Purdue Strategic Ventures, Santuri Ventures, Handshake Ventures, Irongate Capital and Mana Ventures.
ANELLO’s SiPhOG technology integrates high-precision optical fiber gyro performance onto a silicon photonics platform. This innovative solution boasts a low drift rate of less than 0.5° per hour, a compact size comparable to a golf ball, and low power consumption. Additionally, it is designed to withstand shock and vibration while remaining cost-effective compared to traditional fiber-optic gyroscopes.
The technology is tailored for various autonomous applications across multiple sectors, such as land vehicles, UAVs, underwater vehicles, construction and agriculture equipment.
In the context of defense and national security systems, ANELLO’s solutions have demonstrated impressive performance in GPS-denied environments. According to the company, the system can navigate 100 km with less than 100 m of lateral error without relying on GPS and maintains accuracy within 0.1 m over distances of 0.8 km in orchard environments where GPS signals are limited.
ANELLO’s SiPhOG technology aims to bridge the gap between high-performance, expensive sensors such as fiber-optic and ring laser gyros and low-cost, less precise MEMS gyros. This strategic positioning addresses the increasing demand for cost-effective yet high-performance navigation sensors in the expanding autonomous navigation market.
The funding is anticipated to enhance ANELLO’s manufacturing capabilities and product development to meet its goal of delivering reliable navigation solutions for environments where GPS signals are weak or unavailable. These environments include construction sites, agricultural fields, trucking operations, robotics, unmanned aerial and underwater vehicles, autonomous vehicles, as well as defense and national security applications.
IT’S ALL PHYSICS. How things work, that is. Well, maybe a little chemistry too in some cases. I might be a little biased in my opinion given that I’m an applied physicist by training. Radio? Satellite navigation? Yes, the principles of their operation are all governed by physics. Many physicists of my generation started out as radio tinkerers. I’ve recounted in this column before that I built my first radio (from a kit) when I was 14 (not counting the crystal radio that my father helped me to put together when I was 8 or 9). I built a few more during high school, got into radio astronomy as an undergraduate and did a Ph.D. in the application of very long baseline (radio) interferometry to geodesy.
The great American physicist Richard Feynman was also a radio tinkerer in his youth. He recounts in one of his autobiographical books how he used to fix radios. Since he would approach the task of repairing each non-functioning set by first contemplating why it wasn’t working, he got the reputation of fixing radios by thinking!
One of Feynman’s special abilities was in explaining how things worked. In fact, he has been called “The Great Explainer.” He authored what is arguably the best physics textbooks ever produced: The Feynman Lectures on Physics. The three-volume set, developed from his Caltech lectures to undergraduates between 1961 and 1964, covers mechanics, radiation, electromagnetism, matter and quantum mechanics. Many students and practicing physicists have learned or relearned aspects of physics from the famous “red books.” Many more will now thank Caltech, which recently put the Lectures online for anyone to read.
In the February 2016 column, we learned about the development of a microprocessor-controlled multi-element GNSS antenna array for interference rejection. While there are many textbooks that describe how multi-element antennas work, Feynman explains their operation in his Lectures from first principles–from the principles of physics. The phenomenon governing the behavior of antennas with multiple elements is called interference.
If we combine two electromagnetic waves, they will interfere with each other with a result that depends on the relative phase (or phase difference) of the waves. The waves might reinforce each other leading to a larger net amplitude, called constructive interference, or partially or fully null each other out, called destructive interference. When we apply this concept to the signals transmitted by a pair of antennas making up an array in a horizontal plane, we find that the array has directionality. That is, if we space the antennas by one-half wavelength of the signal to be transmitted and feed the antennas in phase (zero phase difference), we will transmit a strong signal in the directions perpendicular to the baseline connecting the antennas (say east-west) and no signal in the orthogonal directions (north-south). If we use this antenna pair for receiving, we will have a null in the reception pattern to the north and to the south and will be insensitive to signals arriving from those directions. And as Feynman describes in his lectures, by adding more antennas to the array and “some cleverness in spacing and phasing our antennas,” we can have a fairly narrow pattern null in a chosen direction. In the case of a GNSS antenna array, that direction might be that of a jamming signal and so we can null out the jammer and maintain a positioning capability.
There is more to it in developing a practical microprocessor-controlled GNSS antenna array, but it starts with the physics.
WingXpand, a U.S. provider of autonomous smart planes with artificial intelligence (AI) threat detection capabilities, has collaborated with RTX’s Raytheon. The partnership aims to enhance the capabilities of WingXpand’s smart planes, which already feature a library of AI algorithms designed to provide soldiers with real-time threat identification.
Enhanced threat detection
The smart planes’ open systems architecture allows for the seamless integration of organic and third-party applications and payloads, designed for mission flexibility as threats and tactics evolve. Raytheon’s advanced infrared technology seeks to enhance the capabilities of WingXpand’s smart planes by improving their ability to detect and identify potential threats at greater distances. This integration allows tactical ground units and command leadership to receive more precise, real-time information about their surroundings, facilitating faster and more informed decision-making in the field.
New VTOL capability
In addition to the Raytheon collaboration, WingXpand has introduced a new vertical takeoff and landing (VTOL) capability for its xRAI smart plane. This feature expands the operational versatility of the aircraft, which is designed to be compact enough to fit in a backpack. The VTOL option allows the xRAI to take off and land vertically, making it ideal for operations in tight spaces and challenging environments. WingXpand’s smart planes can be used in both defense and civil missions.
The GPS World team touched down in Stuttgart, Germany, for INTERGEO 2024, held from Sept. 24-26.
This year’s expo and conference, which attracted more than 17,000 visitors from 121 countries and featured 579 exhibitors, showcased solutions to address critical global issues such as climate change, urbanization and GNSS jamming and spoofing.
Ray Weatherbee, CEO, Stonex USA, and Tim Carolin, Account Executive, GPS World. Photo: GPS World Staff
GPS World Publisher Brian Kanaba and Account Manager Tim Carolin made their debut at the show, joining veteran Editor-in-Chief Matteo Luccio. The team had the opportunity to explore the expansive show floor, experiencing firsthand the latest innovations from around the world. With three floors of exhibits, Kanaba, Carolin and Luccio engaged with partners and established valuable connections with industry leaders. Their attendance highlights GPS World’s dedication to remaining at the forefront of geospatial technology and trends, emphasizing a strong commitment to collaboration and innovation within the industry.
GPS World staff: Matteo Luccio, Editor-in-Chief, Brian Kanaba, Publisher, and Tim Carolin, Account Executive. (Photo: GPS World Staff)
Inertial Labs has introduced its latest GPS-aided inertial navigation system (INS), the INS-DM-FI. Designed with tactical-grade fiber-optic gyroscope (FOG) technology, the system is engineered to meet the demanding requirements of land, marine and aerial platforms.
The INS-DM-FI is a robust, IP68-rated system specifically developed for challenging environments. It offers comprehensive protection against electromagnetic interference and integrates multiple advanced capabilities, including an INS, attitude and heading reference system (AHRS), motion reference unit (MRU) and FOG IMU-based technology. An optional embedded air data computer (ADC) allows for precise determination of position, velocity and orientation for mounted platforms.
The system can deliver precise measurements of horizontal and vertical displacements and absolute orientation (heading, pitch, and roll) in both static and dynamic conditions. The system’s IMU incorporates tactical-grade FOG and MEMS accelerometers for high-precision data collection. It supports multiple GNSS receivers, including NovAtel OEM7, u-blox F9 and Septentrio mosaic-H series, which can process signals from all GNSS satellites.
The INS-DM-FI includes an optional air data Computer supported by two barometers and is compatible with external systems like the Stand-Alone Magnetic Compass (SAMC). The system’s design incorporates the latest sensor fusion filter, anti-jamming and spoofing algorithms, navigation capabilities and comprehensive calibration software.
Silicon Sensing Systems has been contracted by the German Aerospace Centre (DLR) to supply two miniature Pinpoint (CRM200) gyroscopes for the Martian Moons eXploration (MMX) mission. This mission will travel to Mars to survey the two moons that orbit the planet.
The gyroscopes will be installed on the rover vehicle set to explore Phobos — the larger of Mars’ two moons — to collect crucial surface samples. The Pinpoint gyroscopes are designed to detect any unintended movement of the rover on unfamiliar terrain. Depending on the initial assessment of the drivetrain, which includes the gyroscopes, an optional safety module may be activated in the software. This module will automatically prevent instability during the rover’s driving sessions.
Pinpoint completed TID testing at 17kRad Radiation and Proton tests (up to 68 MeV/proton), demonstrating the gyro’s suitability for space requirements.
The size of a small fingernail, at approximately 5mm by 6mm, PinPoint is the smallest gyro in Silicon Sensing’s MEMS product range. This low-drift, single-axis angular rate sensor can be used in various applications. When integrated, these sensors can precisely measure angular rate across multiple axes — any combination of pitch, yaw and roll —while consuming little power.
The MMX mission is conducted by the Japanese Space Agency (JAXA) to explore Mars’ two moons, with contributions from NASA, the European Space Agency (ESA), CNES and the German Aerospace Center (DLR). CNES and DLR are jointly developing a 25-kg rover for the mission. The spacecraft is expected to arrive in Martian space approximately one year after departing from Earth and will then enter orbit around Mars.
It will then move into a quasi-satellite orbit (QSO) around the Martian moon Phobos to collect scientific data, drop the rover and gather a sample of the moon’s surface. After observation and sample collection, the spacecraft will return to Earth carrying the material gathered from Phobos. The current schedule has a launch date in 2026, followed by a Martian orbit insertion in 2027 and a return to Earth in 2031.
Sikorsky, a Lockheed Martin company, and Rain, a provider of autonomous aerial wildfire containment technology, successfully demonstrated how an autonomous Black Hawk helicopter can be commanded to take off, identify the location and size of a small fire and then accurately drop water to suppress the flames.
At Sikorsky headquarters in Stratford, Connecticut, the Rapid Wildfire Response Demonstration showcased the integration of Sikorsky’s MATRIX flight autonomy with Rain’s wildfire mission autonomy system to suppress a fire in its early stages.
Representatives from NASA, the Federal Emergency Management Agency (FEMA), the Defense Advanced Research Projects Agency (DARPA), the Los Angeles County Fire Department, the Orange County Fire Authority and the philanthropic and impact investment community witnessed the demonstration as part of a two-day wildlands firefighting meeting to discuss autonomy.
During the 30-minute flight demonstration, guests used a tablet to command the Black Hawk aircraft to take off, search for and find the fire and then drop water from a Bambi Bucket slung 60 ft beneath the aircraft. Each of three successive water drops extinguished a 12-inch-diameter propane-fueled fire ring emitting a 3-to-6-inch-tall flame, demonstrating the precision of the Rain fire perception and targeting capability. The Rain system also rapidly adjusted the flight path to account for an 8-to-10-knot crosswind during each water drop. Sikorsky safety pilots in the Black Hawk cockpit monitored the flight controls but were hands-off until the aircraft landed.
Trimble has expanded support for The HALO Trust, the world’s largest humanitarian landmine-clearance nonprofit organization. Trimble is donating an additional 175 Trimble Catalyst GNSS systems, including Trimble DA2 GNSS receivers, to help The HALO Trust further its demining operations worldwide.
Building on the impact of the ongoing collaboration, Trimble’s latest donation will support the expansion and productivity of The HALO Trust’s mine clearance teams. The Catalyst GNSS system provides The HALO Trust with a solution for deploying precise mapping capabilities to large field teams across broad geographic areas. More field teams can now be equipped with the necessary tools to safely and efficiently clear landmines, thereby accelerating the pace of landmine clearance globally.
Since receiving Trimble’s product donations and the Trimble Foundation Fund-directed grant, The HALO Trust has made significant progress in landmine and unexploded ordnance (UXO) clearance. From January to September 2024 alone, The HALO Trust cleared 802 minefields and battlefields, covering a total area of 10,400 acres across 12 war-torn countries. During this period, 31,209 landmines and other Explosive Remnants of War (ERW) were safely destroyed — all accurately mapped using the Trimble Catalyst GNSS system. The HALO Trust’s use of Trimble technology has significantly improved operational efficiency and provided essential data for safe land reclamation and development. According to The HALO Trust, the accuracy and reliability of Trimble’s technology have been crucial in ensuring the safety and success of demining operations in areas severely affected by conflict, such as Ukraine, Angola and Sri Lanka.
This is my 300th and last “Innovation” column in GPS World. I have mixed feelings about stopping the column. I’ve really enjoyed doing it for the past 35 years, but editorial deadlines can be difficult to meet sometimes, especially when I’ve got other things to get done or if they come in the middle of a vacation.
To rephrase the old adage, editorial deadlines wait for no one. Looking back, I don’t know how I managed to initially produce six and then 10 columns each year, along with all my other duties as a university professor. Mind you, as I’ll soon discuss, most of the articles in the columns were authored by others. My job mostly was to edit the articles to help the authors tell their stories in a particular GPS World style and sometimes to improve their submitted figures. Additionally, in 2006, I started to write a sidebar called “Insights” to provide some basic background material about each column’s topic. A few years ago, I became editor-in-chief of the Institute of Navigation’s journal NAVIGATION, which takes up a bit of my time, along with lecturing and managing a research team. So, at 75, I thought it might be a good time to lessen the load a little bit.
In this last column, I’m going to tell the story of how “Innovation” came to be and review some of the column’s developments over the years.
How it all began
In the fall of 1989, GPS World’s founding editor, Glen Gibbons, approached Dave Wells, Ph.D., a fellow faculty member in the then Department of Surveying Engineering at the University of New Brunswick (UNB) – about assisting with a “technology/product development column” in the magazine he was about to start. Glen wanted it to provide “an analysis and commentary on the research, development, product issues and needs of the GPS community.” And, since GPS World readers would have marked differences in their knowledge and expertise in the GPS area, “the column should deal with issues that have broad application and interest and are presented in terms that are accessible to as wide a range of readers as possible,” Glen said in a letter to Dave.
Glen had heard about Dave’s (and UNB’s) early involvement with GPS. When I came to UNB in 1981, UNB was already carrying out some of the first theoretical studies on how GPS could be used by surveyors and geodesists for precise positioning. Shortly afterwards, UNB participated in some of the first surveys using the Macrometer V-1000 and Texas Instruments TI 4100 receivers and developed software to process the resulting data. In 1983, Dr. Gerhard Beutler from the Astronomical Institute of the University of Bern came to UNB on a sabbatical and began developing his own GPS data processing software that would eventually become the Bernese GNSS Software or just “Bernese” to those in the know. Somehow, in between our GPS algorithm and software development, teaching, mentoring graduate students and other duties, we managed to self-publish the first textbook on GPS, Guide to GPS Positioning. With a publication date of December 31, 1986, it went on to sell more than 12,000 copies in the English version alone. It was also translated into Chinese, Spanish and Vietnamese. So, perhaps it is not surprising that Glen came to knock on UNB’s door when he was starting up his magazine.
Getting back to Glen’s letter, he went on to say, “It would be possible to handle the preparation or presentation of the column in one of several ways: We could identify a single person who would have primary responsibility for writing all the columns and whose byline would appear on them; we could have a person act as the coordinating editor responsible for obtaining suitable contributions from various authors; or we could establish a collective or institutional editorship with column responsibilities shared among a pool of contributors.”
The letter arrived in early November 1989, and Dave, I and Alfred Kleusberg, Ph.D., who was a research fellow in the department (and subsequently a professor), began to discuss whether we wanted to take on the responsibility for the column and, if so, how we would manage it. I shortly departed to the University of Bern, where I would spend the better part of two months during my first sabbatical. Communication had to take place using e-mail, although phone, telefax and telex were also possible. Universities had e-mail before most other organizations thanks to BITNET (known initially in Europe as the European Academic and Research Network or EARN), a computer network that predated the Internet. My BITNET e-mail address was lang@unb or [email protected]. As I recall, the personal part of the address was limited to at most four characters. So, when UNB joined the Internet, I basically kept the same e-mail address: [email protected]. I talked about GPS and the Internet in the November 1995 edition of the column. But I’m getting ahead of myself.
FIGURE 1: First page of Dave Wells’ notes from December 31, 1989 on how UNB would manage the “Innovation” column. (Photo: GPS World archives)
That December, the three of us more or less agreed that we would handle the column in some form. From Switzerland, I sent Dave a list of 12 possible topics for the column, but I added the rider: “Note that I am not necessarily volunteering to write any of the articles.” As we know, things turned out a little differently. During the university’s Christmas break, after I returned to Fredericton, we met at Dave’s house to discuss how we would manage the column in more detail. We met on New Year’s Eve — a Sunday afternoon — and decided that Alfred Kleusberg and I would manage the column as co-editors, with Dave serving as one of the inaugural members of the magazine’s Editorial Advisory Board. The column editorship was to be a blend of the second and third of Glen’s suggestions. The task wasn’t supposed to be too onerous. After all, the magazine was to be published bimonthly. Lots of time to get someone to write an article and for Alfred and I to edit it. Or so we thought. And the column was to be called, simply, “Innovation.” I don’t recall who came up with the name — whether it was one of the three of us or Glen, but the notes from that Sunday afternoon meeting have “Innovation” written at the top of the first page (see FIGURE 1). Ideally, as per Glen’s suggested guidelines, column articles were to be tutorial in style or written in a way that they could be understood, for the most part, by non-experts in the field.
At that Sunday afternoon meeting, we decided that Dave and Alfred would write the article for the first column. It was an introduction to GPS and some possible applications titled “GPS: A Multipurpose System.” With a couple of iterations of the article back and forth with Glen via fax (GPS World didn’t have e-mail until a few years later) and a figure delivery by FedEx, the column debuted in GPS World, Volume 1, Issue 1, January/February 1990.
It used three different positioning scenarios to explain how GPS could provide positioning accuracies from a Selective Availability-constrained 100 meters down to the sub-centimeter level. It also outlined GPS’s ability to determine platform attitude with multiple antennas and its use for accurate time transfer. There was a brief introductory couple of paragraphs, which would be a column standard (later extended to a sidebar). That first introduction went as follows:
“‘Innovation’ will be a regular column in GPS World and will comment on GPS technology, product development, and other issues and needs of the GPS community. Coordinating editors are Alfred Kleusberg, Ph.D. and Richard Langley, Ph.D. both of the Department of Surveying Engineering at the University of New Brunswick in Fredericton, New Brunswick, Canada, as is David Wells, Ph.D., co-author of this initial column.
“The first few columns will introduce GPS World readers to GPS technology. This first column focuses on the many capabilities of GPS. The next column will look at the flip side — what are the limitations of GPS? ‘Innovation’ will discuss some intriguing questions in future columns: Why is the GPS signal so complicated? How have surveyors been able to use it to get such accurate results? How serious is selective availability? We will also devote columns to exploring in depth some of the issues raised in this column: GPS and electronic charts, GPS and geographical information systems and prospects for using GPS and GLONASS together. We welcome readers’ comments and topic suggestions for future columns.”
That introduction listed the topics for the first year of “Innovation.” They were written by Alfred, me, both of us, or other researchers at UNB and, in one case, by colleagues at the Canadian Hydrographic Service. We had a very positive response to our first few column articles, so Glen kept us on, but at some point in 1990, he told us the magazine was going to 10 issues a year. There were just too many GPS-related developments to be covered in just six issues. So now there would be a monthly column except for the July/August and November/December issues.
In the second year, Alfred and I continued to write some tutorial articles for the column, but we started to invite others to submit articles, which we would then edit for style and space, and that became the tradition. Over the years, we have had hundreds of leaders in GNSS technology development and applications pen articles. In the second and third years of the column, for example, we featured articles by Stephen DeLoach on precise real-time dredge positioning, Jack Klobuchar on ionospheric effects on GPS, Edward Krakiwsky on GPS vehicle location and navigation, Yehuda Bock on continuous monitoring of crustal deformation, Keith D. McDonald on GPS in civil aviation, David Coco on GPS as satellites of opportunity for ionospheric monitoring, Derrick Peyton on using GPS and remotely-operated vehicles to map the ocean, Oscar Colombo and Mary Peters on precision long-range DGPS for airborne surveys, Adam Freedman on measuring the Earth’s rotation and orientation with GPS, Christian Rocken and Thomas Kelecy on high-accuracy GPS marine positioning for scientific applications, Marvin May on measuring velocity using GPS, Thomas Yunck describing a new chapter in precise orbit determination, and Gregory Leger on using GPS-equipped drift buoys for search and rescue operations. And the list goes on and on.
As I mentioned, in the second year of GPS World, there were 10 issues. That changed in 1993, when the magazine went to 12 issues a year, but the September and December issues were “Showcase” issues featuring more industrial news and announcements of new products. It was also to include “The Almanac” — an update on the GNSS constellations, which I also looked after. Eventually, the “Showcase” issues became regular issues but with “Innovation” replaced by “The Almanac” at the “back of the book.”
Figure 2A Different eras of “Innovation” throughout the years; the January 1993 edition (left) and the January 2000 edition (right). (Photo: GPS World archives)
The column look changed a few times over the years, typically coinciding with magazine makeovers, with the logo changing from the original 3D terrain graphic to a logo of people with stuff in their hands starting in January 1999, to a “bits” logo from January 2001, to a somewhat plain format from September 2003, with the “Insights” sidebar and my photo from April 2006, to a circle photo from November 2015, and with a new photo from January 2016. FIGURES 2A, 2B and 2C show representative column snapshots for each era.
Figure 2B Different eras of “Innovation” throughout the years; the January 2003 edition (left) and the September 2003 edition (right). (Photo: GPS World archives)
FIGURE 2c Different eras of “Innovation” throughout the years; the April 2006 edition (left) and the February 2016 edition (right). (Photo: GPS World archives)
The tutorials
As I mentioned earlier, right from the beginning of “Innovation,” we decided to have essentially two types of articles in the column: discussions of recent advances in GPS (and later GNSS) applications and related technology written by guest authors and tutorials explaining the fundamentals of GNSS including how the three main components of GNSS work: the satellites, the control segment and the user equipment. Here is a list of some of the tutorials written by the UNB team (mostly me) that were featured in “Innovation”:
GPS: A Multipurpose System (January/February 1990)
The Limitations of GPS (March/April 1990)
Why is the GPS Signal So Complex? (May/June 1990)
The Issue of Selective Availability (Sept./Oct. 1990)
Comparing GPS and GLONASS (Nov./Dec. 1990)
The GPS Receiver: An Introduction (Jan. 1991)
The Orbits of GPS Satellites (March 1991)
The Mathematics of GPS (July/August 1991)
Time, Clocks, and GPS (Nov./Dec. 1991)
Basic Geodesy for GPS (February 1992)
The Federal Radionavigation Plan (March 1992)
Precise Differential Positioning and Surveying (July 1992)
The GPS Observables (April 1993)
Communication Links for GPS (May 1993)
GPS and the Measurement of gravity (Oct. 1993)
RTCM SC-104 DGPS Standards (May 1994)
NMEA 0183: A GPS Receiver Interface Standard (July 1995)
Mathematics of Attitude Determination with GPS (Sept. 1995)
A GPS Glossary (Oct. 1995)
GPS and the Internet (Nov. 1995)
The GPS User’s Bookshelf (Jan. 1996)
Coordinates and Datums and Maps! Oh My! (with Will Featherstone; Jan. 1997)
The GPS Error Budget (March 1997)
GPS Receiver System Noise (June 1997)
GLONASS: Review and Update (July 1997)
The UTM Grid System (Feb. 1998)
A Primer on GPS Antennas (July 1998)
RTK GPS (September 1998)
The GPS End-of-Week Rollover (Nov. 1998)
The Integrity of GPS (March 1999)
Dilution of Precision (May 1999)
GPS, the Ionosphere, and the Solar Maximum (July 2000)
Navigation 101: Basic Navigation with a GPS Receiver (October 2000)
Getting Your Bearings: The Magnetic Compass and GPS (Sept. 2003)
GPS by the Numbers: A Sideways Look at How the Global Positioning System Works (April 2010); this was the 200th “Innovation” column.
As you can see, the tutorials became fewer as the years went by. As my research career expanded, I just didn’t have the additional time to write more tutorials. I had taken over sole responsibility for the column in 1997, shortly after Alfred Kleusberg left UNB to pursue a career opportunity in Germany.
However, the tutorial columns were (and still are) popular judging by the comments sent to GPS World and the number of citations for some reported by Google Scholar. For example, the one on dilution of precision has been cited in papers, theses, and reports 837 times to date. While not as many as a paper on an important medical breakthrough, it’s not a bad record for an article on a navigation topic.
Changes at the top
The column has seen four changes of editorial leadership at GPS World. Glen Gibbons, the founding editor, stepped down as editor-in-chief in July 2005 and shortly afterward started up his own publishing company to produce the magazine Inside GNSS. Alan Cameron took over the job in 2006, and subsequently became the magazine’s publisher and editor-at-large. Tracy Cozzens became the senior editor in 2019 with responsibility for “Innovation,” and then Matteo Luccio became editor-in-chief of the magazine in May 2021. I’m happy to say I got along well with all of these “bosses,” and they continued to put up with me even when I got the column in at the last moment. Additionally, the magazine’s various art directors over the years have always made the column look good.
However, after I took over sole responsibility for the column, there were no changes at the bottom. So, I’ve ended up being the longest serving GNSS rapporteur or editor, with Glen and Alan and Tracy having retired at different epochs during the past decade. In addition to the column, I have contributed a number of shorter articles to the magazine and the GPS World website over the years, sometimes joined by colleagues from different organizations, in particular the German Aerospace Center.
A bit of my own history
I wasn’t going to bother with an “Insights” sidebar for this last column. The column isn’t about a single topic that needs any background information. But you might be wondering how I got this gig as the “Innovation” editor (apart from what I’ve already told you) or got my job at UNB for that matter. So, I’m repurposing the “Insights” sidebar from the February 2016 issue of GPS World, in which I talk a bit about antenna arrays and my own radio tinkering. It doesn’t mention that after getting my Ph.D., I spent two years at MIT as a postdoctoral fellow working under the famous physicist Irwin Shapiro on analyzing lunar laser ranging data to uncover subtle changes in Earth’s rotation due to the fluctuating winds of its atmosphere. Even as a graduate student, I was involved with satellite navigation and helped to uncover a bias in the coordinate system used by the U.S. Navy Navigation Satellite System, commonly known as Transit, by comparing station coordinates with those I obtained in my very long baseline interferometry research. I’ve always been a radio nerd both in my day job and as an avid shortwave radio hobbyist. So, it is not too surprising that I got involved with GPS and then GNSS (including ionospheric studies) and established a GNSS research group at UNB with some stellar graduates over the years.
And there you have it. It only remains for me to thank all of the authors who have shared their research and understanding of the many facets of GNSS in the column over the past three-and-a-half decades, the staff at GPS World for getting the column into the print and later the electronic editions on the Web, the readers whose positive feedback encouraged me to keep the column going, and to my wife, Marg, who let me spend the long hours on the column when I should have been attending to things around the house. So, now, to paraphrase a much better journalist than I: Goodbye, and good luck.
The November 2024 issue of GPS World features Professor Richard Langley’s 300th and final “Innovation” column. His first one appeared in the January/February 1990 issue, the magazine’s very first. In celebration of Richard’s decades-long contribution to GPS / GNSS / PNT, we are publishing a selection of testimonials and photos from some of his colleagues and friends, gathered by his former students Sunil Bisnath and Attila Komjathy. Click here to read the testimonials.
Successful launch of the 59th and 60th BDS satellites on Sept. 19, 2024. (Photo: International Cooperation Center of China Satellite Navigation Office)
Upholding the principles of “superior construction, excellent management, and substantial development,” the BeiDou Navigation Satellite System (BDS) implements multifaceted strategies to ensure uninterrupted and stable system operations and services, with its backup satellites launched into orbit as per the scheduled plan in 2024. Concurrently, research on next-generation BDS technology upgrades and related technological trials for integration with low-Earth orbit (LEO) positioning, navigation and timing (PNT) systems are vigorously promoted, further enhancing international collaboration and propelling the continuous advancement of BDS in the new era.
1. System operation and services
All figures provided by the author.
BDS currently consists of 45 operational satellites in orbit, delivering services through 15 BDS-2 and 30 BDS-3 satellites. Since May 2023, five BDS-3 backup satellites have been launched to bolster system resilience.
According to the monitoring data from the International GNSS Monitoring and Assessment System (iGMAS) and the International GNSS Service (IGS) in 2024, BDS achieves a service availability of 100% and exhibits a single satellite signal continuity of 99.991% per hour, with signal-in-space accuracy surpassing 0.9 meters (95%), broadcast ephemeris accuracy surpassing 0.2 m (95%), single frequency three-dimensional positioning accuracy of the B1C signal better than 6 m (95%, global average), and the B1C/B2a dual-frequency three-dimensional positioning accuracy superior to 3 m (95%). The timing accuracy is noted to be better than 10 ns (95%). The performance of the BDS PNT service has consistently met all performance requirements.
Figure 1 illustrates the spatial signal accuracy of the BDS B1C signal. Figure 2 presents the broadcast orbit accuracy of the BDS B1C signal. Figure 3 showcases BDS’ global positioning accuracy for both single-frequency and dual-frequency.
Through the BeiDou Satellite-Based Augmentation System B1C (BDSBAS-B1C) and the BeiDou Satellite-Based Augmentation System B2a (BDSBAS-B2a) signals, BDS offers single-frequency BDSBAS service that meets APV-I requirements and a dual-frequency multi-constellation service that meets CAT-I requirements for China and surrounding regions. The ionospheric grid model has been persistently refined to enhance the performance of the satellite-based augmentation services at the peripheries. Evaluation results reveal that the BDSBAS service attains a single-frequency positioning accuracy of 1.29 m (95%) horizontally and 1.99 m (95%) vertically, and a dual-frequency positioning accuracy of 0.77 meters (95%) horizontally and 1.41 m (95%) vertically.
BDS disseminates precise orbit and clock difference corrections and inter-code biases via the precise point positioning (PPP)-B2b signal, providing PPP services to China and surrounding areas. Evaluation results indicate that the BDS-only precise point positioning accuracy is 0.16 m (95%) horizontally and 0.22 m (95%) vertically, with a convergence time of less than 20 minutes.
In 2024, building upon its PNT services, BDS actively offers diversified specialized services, including regional short message communication, global short messaging, and international search and rescue. The number of user terminals for regional short message communications continues to grow. Based on inter-satellite links, global short messaging services can provide users with global random-access capabilities. These services have been applied in projects such as the Einstein Probe mission, the SVOM satellite in collaboration with France, and gravitational wave detection satellites, achieving instant return of global detection data. While six medium-Earth orbit (MEO) satellites are equipped with international maritime search and rescue payloads, the BDS return link enables transmission with a communication delay of less than 12 seconds, and a success rate of 96.82%, suitable for distress alert feedback, disaster information broadcasting and other multi-application scenarios.
The stable BDS operation ensures the consistent and rapid improvement of application industries and the expansion of application scenarios. In 2023, the total output value of China’s satellite navigation and location-based service industries reached more than RMB 530 billion, marking a growth of more than 7% compared to 2022.
2. System construction and development
In May 2023, a backup geostationary orbit (GEO) satellite was launched, followed by two additional MEO backup satellites launched in December 2023, featuring upgraded global short message communication capacity and enhanced intelligent payload technologies. These backup satellites have successfully completed in-orbit testing and are now ready to provide services as needed. In September 2024, another pair of MEO backup satellites, equipped with innovative atomic clocks and a new type of inter-satellite links, were deployed. These backup satellites improve system reliability and service performance and facilitate experimental validation for next-generation satellite technology upgrades.
To continuously enhance system service performance, BDS has developed precision and stability enhancement plans for both the ground control system and the in-orbit satellite support system. Efforts include intensifying satellite-based and ground-based multi-source data fusion analysis, conducting regular assessments of constellation and ground system statuses, and improving fault automatic diagnosis, response efficiency, and intelligence capacity.
China is actively promoting the integrated development and experimental validation of BDS and LEO satellite navigation augmentation systems. Leveraging several test satellites within the under-construction LEO constellation, experiments including GNSS+LEO FPPP have been conducted. Results demonstrate that GNSS orbit determination accuracy is better than 5 cm (1σ), and clock error determination accuracy is superior to 0.15 nss (1σ). With signal enhancement from two to three LEO satellites, PPP positioning accuracy reaches 0.3 m with a convergence time at the minute level, thereby enhancing high-precision service performance and reducing PPP convergence time.
In May 2023, China successfully launched the first BDS-3 GEO backup satellite. (Photo: International Cooperation Center of China Satellite Navigation Office)
3. International coordination and cooperation
China has been deeply involved in international satellite navigation. Since 2023, China has actively participated in a series of events under the United Nations framework, including the ICG-17 and the United Nations Workshop on the Application of Global Navigation Satellite Systems, contributing to the global advancement of satellite navigation. China has engaged in deep collaboration with system providers from the United States, Russia and the European Union to facilitate compatibility and interoperability, covering navigation signal structures, time systems, coordinate frameworks, test and assessment. Meanwhile, discussions are held with regional navigation satellite systems and emerging systems on topics of mutual interest, such as high-precision services and emergency alert services. In 2024, the BDS timing service was officially included in the Time Bulletin by the Bureau International des Poids et Mesures (BIPM), signifying international recognition of the ability to provide precise and reliable standard time services globally.
China continues to expand its international partnership with BDS. In recent years, events including the BDS/GNSS Global Partner Forum, the China-Africa BDS Cooperation Forums, the China-Arab States BDS Cooperation Forums, the China-Central Asia BDS Cooperation Forums, the International Training Workshop on BDS Technologies and Applications in the Belt and Road Countries and Regions and the International Summit on BDS Applications have been held to share the benefits of BDS/GNSS applications globally.
BDS will continue to uphold the vision of “a first-class navigation satellite system developed by China and dedicated to the world.” It will make every effort to ensure the stable operation, steady upgrades, and advancements of the system, as well as in-depth research in technologies such as low-orbit PNT and lunar PNT, furthering the commercialization, industrialization, and internationalization of BDS applications
Citing a need for better “positioning, navigation and timing (PNT) resilience, availability and continuity,” a market consultation document from the EU’s Joint Research Center (JRC) says establishing a resilient PNT ecosystem is essential for “…EU autonomy, the economy’s overall resilience and EU global standing.” Therefore, creating this system-of-system ecosystem “… should be considered a critical priority for the EU.”
According to the JRC, complementary (or continuous) PNT, or C-PNT, is the combination of existing space assets (GNSS) and future services that can work together in the multi-system ecosystem. This extends the service to areas where GNSS is not available and increases overall resilience.
The JRC document goes on to say, “The first step towards the creation of such a C-PNT ecosystem is the deployment of the terrestrial timing backbone.”
Such a backbone would:
Interconnect existing Member States (MS) National Metrological Institutes (NMI) and National Research and Education Networks (NREN) architectures into a pan-European network.
Maintain and (if possible) enhance the existing use cases (NMI, NREN and their existing commercial customers) and enable time connections to critical entities (CE), as regulated by the directive on the resilience of critical entities, while also promoting GNSS for additional resilience.
Enable the commercial utilization of timing backbone to enhance EU competitiveness and enable further growth.
Responsibility for navigation issues with the European Union is somewhat dispersed. The European Radio Navigation Plan is developed as a staff working document published by the European Commission’s Director General for Defense, Industry and Space (DG DEIFS). This directorate implements the EU Space Programme, which is, in turn, managed by EUSPA, an EU executive agency.
At the same time the European Space Agency’s Navigation Directorate is responsible for “…positioning, navigation, and timing services of the European satellite navigation system Galileo and the augmentation system EGNOS” under agreement with EC. It is also responsible for ”…exploring future applications of navigation technologies for science and daily life.”
This latter includes the Navigation Innovation and Support Program (NAVISP). And while space is an important consideration in NAVISP, the program has funded some decidedly non-space projects such as the UK’s MarRINav effort which focused on terrestrial PNT, and development of an eLoran antenna for handheld devices.
The Joint Research Center supports a wide range of EU stakeholders for PNT efforts including DG DEFIS, ESA, member states, and pan-European organizations.
A “market consultation” may not seem to many as an affirmative step toward establishing a timing backbone for Europe. Experienced observers, though, point to the wealth of documentation both ESA and DG DEFIS have produced on the need for PNT resilience and the benefits that will accrue to member nations.
“The EU is very consultation and consensus-driven,” says timing expert Magnus Danielson at Net Insight. “So, you are not going to see the kind of top-down orders to do things as you might for a single state. Some of these decisions are made by each member state, as they should be. I am sure (European) Commission and ESA officials have seen what Sweden has done with distributed timing clocks operated by Netnoed, what the U.K. NPL is doing with its clock network, and are concerned about Russian jamming and spoofing in Ukraine and the Baltic. It’s pretty easy to connect the dots and make reinforcing PNT for Europe’s critical infrastructure and applications a priority. Working with the EC-JRC to develop this has been rewarding. Here’s hoping they move quickly enough. Several member states and friendly neighbors have already responded positively, and I sure the market consultation feedback will aid in moving decisions forward.”
The concept of a system-of-systems approach to resilient PNT that is underpinned by network timing is not a new one. The 2008 U. S. National PNT Architecture articulated such an approach, though it was never implemented. In 2020 the RNT Foundation expanded on this idea in a paper advocating a U.S. national resilient timing architecture using signals from space, fiber, and terrestrial broadcast. China’s National Timing Service Center adopted a similar strategy. Media reports indicate China has completed or will soon complete its High Accuracy, Ground-based Timing System with 20,000km of fiber, 295 timing stations, and nation-wide eLoran service.
The EU is asking for input about a European Timing Backbone and is interested in hearing from anyone, whether or not they are EU citizens.*
