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This is an introduction to the August 2023 Innovation article, “Far Out: Positioning above the GPS constellation”

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On October 25, 1997, a defense satellite was launched from Cape Canaveral on an Atlas rocket with a Centaur upper stage. The Centaur went into an elliptical geosynchronous transfer orbit with an apogee close to geostationary orbit radius before releasing the satellite. Bolted to the side of the Centaur was an instrument package containing a GPS digital sensor. This piggyback device was part of an experiment by students at the U.S. Air Force Academy to test some of the concepts of GPS navigation for high-altitude spacecraft.

The sensor captured 40-millisecond samples of GPS L1 signals collected by a patch antenna. The digital samples were downlinked to a ground station in Colorado Springs where they were subsequently processed. The equipment successfully operated from November 3 until at least November 9. During that time, GPS signals were detected across a wide range of altitudes above the GPS constellation including at times when the Falcon Gold antenna was only in view of a GPS satellite’s transmitting antenna sidelobes. The downlinked data was carefully archived. The Falcon Gold experiment was discussed by Thomas Powell of the Aerospace Corporation in an article he wrote for this column in October 1999 entitled “The View from Above: GPS on High-Altitude Spacecraft.”

Fast forward a couple of decades. Researchers at the University of Minnesota are taking a fresh look at the Falcon Gold data using some innovative analysis tools, which may prove beneficial for processing GNSS data from receivers on other satellites flying above the GNSS constellations even all the way to the Moon. In this quarter’s Innovation column, they tell us about their work and its potential benefit.

This Falcon Gold data study is a great example of how archived GNSS data can be reanalyzed with fresh insight and new techniques to milk even more and better results from the data. Another important example is the wealth of data that has been acquired by the International GNSS Service since beginning operations in 1994. The data in the archive is reprocessed from time to time to produce a more consistent long product set for analysis of sources of systematic error and to improve its ultimate accuracy. This results in a better understanding of Earth system dynamics, for example, including plate tectonics. The data from many other GNSS instruments flown in space is also archived allowing look backs for further and more detailed analyses. This includes my GPS Attitude, Positioning, and Profiling (GAP) instrument on the CASSIOPE scientific satellite, now part of ESA’s Swarm constellation. Researchers continue to produce interesting scientific results from the GAP data. So, it’s not always necessary to generate fresh data for a study – useful data may already exist. What’s old can indeed be new again!

ANELLO Photonics has released its GNSS inertial navigation system (INS), which is designed for reliable long-term GPS-denied navigation and localization.

Powered by ANELLO’s optical gyroscope technology and artificial intelligence-based sensor fusion engine, the ANELLO GNSS INS delivers robust, high-accuracy positioning and orientation for applications such as agriculture, construction, trucking, and autonomous vehicles.

The ANELLO GNSS INS comes equipped with unaided heading drift of less than 0.5°/hr, dual multi-band real-time kinematic capable GNSS engines, ASIL-D ready automotive qualified CPU, automotive 2-wire Ethernet, and dual high-speed CAN FD interfaces.

It also features dual RS-232 interfaces, hardware precision time protocol, IEEE 802.1AS. The ANELLO GNSS INS is IP68 waterproof, as well as resistant to dust, salt spray and chemicals.

In a biological preserve in Mexico’s Campeche State, a team of archaeologists have documented pyramids, palaces, a ball court and other remains of an ancient city they call Ocomtún, reported the New York Times.

Archeologists surveyed the site for six weeks in May and June, finding  50-foot-tall (15.2-meter-tall) structures resembling pyramids, as well as pottery and Mayan engravings they believe date to between 600 and 900 AD. The team determined the city was likely abandoned more than 1,000 years ago.

Mexico’s National Institute of Anthropology and History (INAH) hailed their findings late last month, saying they discovered the ancient city in “a vast area practically unknown to archaeology.”

“I’m often asked why nobody has come there, and I say, ‘Well, probably because you need to be a little nuts to go there,” said Ivan Sprajc, the survey’s lead archaeologist and a professor at a Slovenian research center, ZRC SAZU. “It’s not an easy job.”

Surveying the area has been revolutionized over the last decade by lidar — allowing researchers to survey densely forested areas that are difficult to explore on foot. Archeologists were able to use airborne lasers to pierce through dense vegetation and reveal the ancient structures and human-modified landscapes beneath.

INAH described the site as having once been a major center of Mayan life. Surrounded by wetlands, Ocomtún includes pyramids, plazas, elite residences and “strange” complexes of structures arranged almost in concentric circles, Dr. Sprajc told CNN.

“For example, we have several very curious architecture complexes of structures which are arranged in almost concentric circles. So, we are only guessing what this could be. Perhaps marketplaces,” he added.

Mexico’s National Institute of Anthropology and History team plans to return next year for further investigation.

China’s BeiDou GNSS is newer, has more features, is more accurate, and has more satellites in the skies of more nations than the venerable U.S. GPS, according to Sarah Sewall, Executive Vice President for Strategic Issues at IQT.

More than that, it is one example of “a new form of great power competition that most in the U.S. government don’t recognize,” she said. China is providing superior precision, navigation, and timing information to enhance its diplomatic, economic and military power and the United States cannot afford to cede this area of longstanding advantage.

In a recent paper published by Harvard’s Belfer Center for Science and International Affairs, “China’s BeiDou: New Dimensions of Great Power Competition,” Sewall and co-authors Tyler Vandenburg and Kaj Malden outline their finding that China’s version of GPS is part of a longstanding effort to join the technological ranks of leading nations and leverage its capabilities to achieve geopolitical advantage in many areas.

“First, the global reach of BeiDou ensures that the Peoples’ Liberation Army is no longer dependent on another nation’s satnav. China’s economy — and those of other nations relying on BeiDou — can continue to function even if GPS is degraded or denied,” Sewall stated. “This may increase Beijing’s incentives to attack other national satellite capabilities.”

“BeiDou is also an economic driver for the Chinese economy and innovation. The output of China’s commercial space and navigation services industry has increased by tens of billions in the last decade, and new applications such as precision agriculture and self-driving cars show no sign of slowing,” Sewall continued.

The focus of Sewall’s paper, though, is the way BeiDou supports China’s Belt and Road and Digital Silk Road initiatives to gain influence and leverage around the world. She points out that in cases where BeiDou provides the most accurate positioning, navigation, and timing (PNT) data, particularly in the global south, China may be able to hold much of another nation’s economy hostage.

The BeiDou constellation has more satellites than GPS or any other system. It also has more than ten times the monitoring stations in other countries than have been deployed for GPS. As a result, in many places, particularly in the developing world, BeiDou’s accuracy is much better.

Her assessment of BeiDou’s technical superiority received some unexpected support recently from a government advisory board on GPS. It reported that “GPS’s capabilities are now substantially inferior to those of China’s BeiDou,” and urged the administration to regain U.S. leadership in the field.

Being newer and more advanced makes it easier for China to encourage other nations to use BeiDou signals and purchase specialized equipment, especially when equipment purchases are heavily subsidized by the Chinese government.

This is important because systems such as GPS and BeiDou provide more than just directions to the nearest coffee shop. Their precise PNT signals are used for everything from synchronizing cellphone networks and industrial machine controls, to time stamping financial transactions, and coordinating electrical grids. GPS has been called “the silent utility” because signals are used in almost every technology.

“It is very difficult for government leaders in the developing world to turn down discounted infrastructure and opportunities for economic development,” Sewall said. “Even if they know that tying that infrastructure to Chinese signals may give the CCP [Chinese Communist Party] a future on/off switch to their economies.”

The West and the United States in particular, faces challenges confronting China’s efforts with BeiDou, according to Sewall.

“Many in government equate national power with military power, but that’s a narrow and insufficient formulation, particularly in the 21^st century,” Sewall said. “American officials under appreciate China’s efforts to create commercial technology dependencies abroad. The United States has left a vacuum in the developing world that our industry is seemingly unable to fill in the face of competition from Chinese firms that are heavily supported by their government.”

Sewall describes a Chinese “tech stack” being exported that include BeiDou services as part of Belt and Road and Digital Silk Road. It is comprised of a hierarchy of equipment that includes network cables, servers, and cell phones.

“We don’t really have a democratic approach to help foreign nations make meaningful technology choices. We risk ceding global infrastructure to China if we fail to help Western firms offer their own integrated products and services to the developing world,” she said.

If we recognized this new form of great power competition, America could easily leap frog China in areas such as satellite navigation, said Patrick Diamond, a member of the President’s Advisory Board on GPS.

“We could provide higher accuracy GPS and make signals much more secure though internet delivered authentication,” Diamond said. “We could offer complementary terrestrial systems to GPS that would give other nations their own sovereign source of precise time and location while at the same time cooperating with our signals from space.”

“Competing effectively with China in the coming decades will require Americans to think more holistically,” Sewall said, “from realizing that GPS is not just about the military and space, to understanding that national power is more than the ability to prosecute war.”

u-blox has released the LEXI-R4, a module customized for size-constrained application requirements. The device is suitable for small asset trackers, such as pet and personal trackers, micro-mobility devices, and luggage tags.

The LEXI-R4 module supports all LTE-M and NB-internet of things (IoT) bands, with an RF output power of 23 dBm. It is natively designed to support GNSS AT commands, and its dedicated port enables easy integration with any u-blox M10-based GNSS module, such as the MIA-M10.

Additionally, the module can connect to additional positioning services, such as AssistNow and CellLocate.

The compact size of the module, measuring 16 mm x 16 mm, results from a 40% footprint reduction in dimensions compared to the previous u-blox SARA-R4. Due to its small size, remaining space could host larger antennas, which can improve RF performance, or accommodate larger-size batteries.

Another feature of the LEXI-R4 is its 2G fallback capability. Whenever LTE-M/NB-IoT coverage conditions are not optimal, it continues to function by falling back onto a 2G network. The company said this feature could be helpful in countries where LTE-M/NB-IoT networks have yet to be fully deployed.

“Seen & Heard” is a monthly feature of GPS World magazine, traveling the world to capture interesting and unusual news stories involving the GNSS/PNT industry.

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Bikes get tricked out

Snik Bike is a new app-paired tracking device designed to help users track their bikes if they are lost or stolen, reported North Shore News. Snik Bike Security Co-founder Fraser Vaage developed Snik Bike after having two of his bikes stolen. Snik equips any bike with a rechargeable location device that can be installed in five minutes or less. After pairing the device, the bike is automatically registered with Project 529, which is an online bike registration service. Vaage emphasized that while this device is not a ride-tracking software, such as Strava, it acts as an odometer, tracking overall mileage. The battery is only activated when a bike is stolen, Vaage said, therefore, it’s unlikely Snik will run out of battery. However, if it does, the device diverts to AirTag technology as a backup.

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Lighthouses no more

With the wide adoption of GNSS, lighthouses on U.S. shorelines are no longer needed for navigation. To preserve these properties, the General Services Administration has been transferring ownership of the lighthouses to anyone willing to preserve them, reported The Guardian. This year, six lighthouses are being offered to federal, state or local government agencies, non-profits, educational organizations or anyone willing to make them publicly available for educational, cultural, or recreational purposes.

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Location data ad weather resiliency

A Southern Methodist University research team, led by Nicos Markris, measured Dallas’ resilience by recording anonymous cell phone location data among residents in the Dallas metroplex before, during, and after the February 2021 North American winter storm. Measuring a city’s resilience is critical for planning responses to future events and uncovering potential vulnerabilities. By averaging location data, Makris and his team outlined the movement patterns of Dallas residents during a typical week. They compared the normal movement patterns to those during and after the week of the winter storm to determine when Dallas started getting back to normal.

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GPS mitigates natural disasters

NASA’s Jet Propulsion Lab (JPL) is testing new ways to detect tsunami-like ocean waves before they cause catastrophic damage. The GNSS Upper Atmospheric Real-Time Disaster Information and Alert Network (GUARDIAN) is a new experimental monitoring system that can use data from clusters of GPS and other satellites to detect deadly waves triggered on Earth. Radio signals from GNSS are examined by scientific ground stations around the world. That data is then reviewed by the JPL’s Global Differential GPS network to help mitigate disasters. The GUARDIAN is still evolving and may be used in the future to develop early warning strategies, according to the United Nations’ International Committee on GNSS.

Wildfires have recently spread across Greece, Italy, Spain, Portugal, Algeria, Tunisia and Canada, causing mass environmental and economic damage as well as human casualties. Scientists have warned that wildfires are becoming more frequent and more widespread.

In response, an upgraded version of the World Fire Atlas from the European Space Agency (ESA) is now available. The atlas provides a detailed analysis and map of wildfires across the globe.

Rising global temperatures and the increased extreme weather has led to a surge in the number of wildfires rapidly consuming extensive areas of vegetation and forested lands.

Considering the severe wildfires, ESA has reopened its World Fire Atlas which offers an insight into the distribution of individual fires taking place at a global scale.

Through its interactive dashboard, users can compare the frequency of fires between countries as well as analyze the evolution of each wildfire taking place over time. The atlas was first available in 2019 and it supported both European civil protection agencies and firefighters.

The dashboard uses night-time data from the sea and land surface temperature radiometer (SLSTR) on board the Copernicus Sentinel-3A satellite. Working like a thermometer in the sky, the sensor measures thermal infrared radiation to take the temperature of Earth’s land surfaces which is used to detect the fires.

Data from the Copernicus Sentinel-3B satellite will be added to the atlas in December.

Over the previous seven years, data from the World Fire Atlas show a substantial number of fires detected in Portugal, Italy, Greece, France and Spain.

Data also shows that Canada has experienced 11,598 fires during the first seven months of this year alone. This is a 705% increase compared to fires detected over the same period of the previous six years. Canada is currently battling the country’s worst wildfire season on record, with more than 10 million ha of land burned, which is said to increase in the coming weeks.

The Japan Meteorological Agency (JMA) has reported that on July 10-17, data from GNSS signals indicated continuing minor inflation at shallow depths beneath Mount Ioyama, located on the northwest flank of the Karakuni-dake stratovolcano in the Kirishimayama volcano group in Japan.

Shallow volcanic earthquakes were recorded and vigorous fumarolic activity was visible at the fumarolic on the south side of Mount Ioyama. The alert level remained at two, on a five-level scale, and the public was warned to stay 1 km away from Mount Ioyama.

This JMA report was noted on July 18 in the Weekly Volcanic Activity Report, which is a cooperative project between the Smithsonian Institution’s Global Volcanism Program and the Volcano Hazards Program of the U.S. Geological Survey. The report is updated every Wednesday and averages 16 reported volcanoes.

Innoviz Technologies, a lidar technology company, and the BMW Group, a manufacturer of vehicles and motorcycles, have collaborated on a B-sample development phase for a new-generation of lidar. Under the development agreement, Innoviz will develop the B-samples based on its second-generation InnovizTwo lidar sensor to enable Level 3 automated driving capabilities.

“Lidar is one of the critical technologies underpinning Level 3 or even higher automated functions,” Nicolai Martin, BMW Group’s SVP of driving experience, said. “Optimizing lidar technologies and costs are the major challenges in order to bring Level 3 highly automated driving into the mainstream.”

The companies already have been working together for a few years on an existing program that includes the first deployment of lidar-enabled highly automated technology on the BMW 7 Series, which will launch later this year.

In addition to the lidar solution for the BMW 7 Series, the BMW Group and Innoviz have started the first phase of development for a lidar-based minimal risk maneuver system (MRM). The MRM acts as a secondary safety driving decision platform that will leverage the InnovizTwo lidar sensor to manage real-time driving decisions.

Anyone keeping up with my columns may know that I have been highlighting the geodesy crisis and programs that advance the science of geodesy (July 2020, November 2022, December 2022, and March 2023). On June 13-15, I had the privilege of participating in a working group event convened by the Geomatics Emerging Scientist Consortium for Education, Research and Capabilities Enhancement (GEO-ESCON). The GEO-ESCON, established in the summer of 2022, is a multi-university consortium serving the need of the Office of Geomatics of the National Geospatial-Intelligence Agency (NGA) for personnel with advanced geomatics expertise, a sustainable pipeline of critical geomatics skillsets, and capabilities enhancement in geomatics and other applied sciences. The 15-member consortium is led by The Ohio State University (OSU), which serves as GEO-ESCON’s managing higher education partner.

GEO-ESCON is part of OSU’s Battelle Center for Science, Engineering and Public Policy in the John Glenn College of Public Affairs. As stated in an OSU press release, OSU was selected for its role with GEO-ESCON because of its longstanding commitment to geodetic education — its collegiate geodetic program is the oldest in the United States and offers undergraduate and graduate degrees in both geodetic engineering and geodetic science.

OSU is home to more than 80 researchers across six colleges who focus on core research and development aspects of geospatial science and technology, including geodesy, remote sensing, photogrammetry, GIS, positioning, navigation, and timing (PNT), computer vision, mobility, smart cities, data analytics, autonomous systems (UAS, UUS and UGV), medical imaging, and precision agriculture.

The GEO-ESCON consortium is designed to create a geographically distributed, multi-disciplinary network of universities to educate the federal geomatics workforce at advanced levels and provide opportunities for applied research and technology development. Higher education institutions are invited to participate in GEO-ESCON based on their capabilities in geomatics. As of July 18, the consortium has 15 members and two additional universities are in the process of becoming members. Click here for all GEO-ESCON member institutions.

GEO-ESCON convened the June Geomatics Challenge Working Group to discuss pressing geomatics challenges and discuss potential solutions. The event facilitated dialogue between representatives from NGA’s Office of Geomatics and academic attendees on geomatics challenges of national priority that could result in actionable proposals to address the challenges. The working group enables representatives of GEO-ESCON member institutions to gain a deeper understanding of NGA’s geomatics priorities, build relationships with NGA leaders, collaborate with colleagues at other institutions, and provide recommendations to GEO-ESCON and the NGA. There were 47 academic participants representing 14 universities.

NGA aims to encourage institutions with varied expertise to propose solutions that achieve greater outcomes through collaborative work. The agency provided six broad categories of geomatics challenges for discussion. See the image below for the categories of interest.

Proposals submitted in response to the June Geomatics Challenges Request for Proposals (RFP) will be eligible for funding consideration and selected activities are expected to be awarded before the fall semester.

The word “tradecraft” in the categories of interest was intriguing. In general, tradecraft refers to the skills, techniques, and practices used by professionals in various fields to carry out their work effectively and discreetly. During World War II, however, the term became associated with spy work and now is mostly used to refer to the techniques and procedures of espionage. NGA is concerned with the dramatic drop in the number of individuals pursuing careers in geodesy — that is, the geodesy crisis in the United States.

Event attendees were asked to prioritize the topic(s) that most interested them, so that they could join a small group on the topic to identify issues, and discuss approaches, solutions, and potential actions for the challenge. Several universities had multiple representatives, so they selected different topics aligned with their individual interest.

The meeting had professional workshop facilitators, technical advisors, NGA subject matter experts (SME), and student recorders. Facilitators encouraged the full participation of all attendees to elicit a range of viewpoints and generate previously unconsidered solutions that could bridge differences in approach — resulting in solutions that were supported by many.

The small groups aligned with a specific challenge utilized the expertise of technical advisors — experts in geomatics or related fields with considerable industry, government, and/or research experience — who supported the development and maturation of proposed Geomatics Challenge solutions. The role of technical advisors was to work with the other leaders in their small group to encourage the full participation of all attendees and mentor the groups toward the generation of novel solutions. I was a technical advisor for the “unified height” topic.

NGA’s SME participated in the working group activities and provided additional context for the individual topics, and other unclassified details related to the Geomatics Challenges.

To capture the discussions at the group meetings, student recorders took detailed notes during the small group discussions. The recorders were graduate students — primarily in geodesy or other STEM fields — and they did an excellent job of capturing the discussion, action items, and potential proposals.

As previously stated, individuals self-selected the topic that interested them but over the course of the three-day meeting individuals were asked to participate in other Geomatics Challenge small groups to provide constructive critiques to produce the best research projects. This was an excellent concept that, in my opinion, helped to improve draft proposals and identify new collaborative projects.

As an example, the need for a unified height system that defines, assesses and correlates all height measurement processes became very evident when individuals participating in the “remote sensing and geophysics” topic engaged with the “unified height” topic members. This joint-topic group meeting helped form new partnerships and formulate new proposals.

The GEO-ESCON and the participating institutions have an ambitious schedule of submitting and awarding the grant proposals before the end of the government’s fiscal year. That said, the participants appeared to be up to the challenge and prepared to make it happen. For obvious reasons, I cannot describe any of the projects discussed, but I will highlight them when they become available for public distribution.

For now, I would like to state that GEO-ESCON is a great program, and it supports the advancement of the science of geodesy and geomatics. I believe that integrated and collaborative organizations are necessary for the successful development of geospatial products and services, and GEO-ESCON is the epitome of this concept. If you believe your institution would benefit from joining this consortium, I encourage you to visit their website to learn more or reach out directly to GEO-ESCON’s team (geoescon@osu.edu). Click here to subscribe and stay up to date on GEO-ESCON news.

In conclusion, as in my previous column, I would like to remind everyone that geodesy is the foundation for all geospatial products and services.