Study by U.S. government agency responsible for maintaining national time scale shows that Satelles provides a signal that is independent of GNSS and delivers exceptional timing stability
Following a detailed performance study in 2020, the U.S. National Institute of Standards and Technology (NIST) determined that Satellite Time and Location (STL) is a reliable source of timing highly consistent with Coordinated Universal Time (UTC). The secure STL services are provided by Satelles Inc.
STL is based on a signal independent from GPS and other GNSS. The STL service was able to deliver this consistent performance in a deep indoor environment where GNSS signals did not reach.
The results of the study were shared by Elizabeth Donley, chief of the Time and Frequency Division at NIST, in a keynote speech at the Workshop on Synchronization and Timing Systems (WSTS) conference on April 1.
Donley articulated the details of the NIST study, in which a GPS-disciplined clock and a Satelles EVK-2 evaluation unit with a quartz oscillator were compared to UTC for 50 days. In this evaluation, the GPS device received its signal from an outdoor antenna, whereas the Satelles device was connected to an indoor antenna in a deep indoor environment where GNSS signals were not able to reach.
Time deviation calculations estimated the stability of the two signals with respect to the UTC time scale. Based on one day of averaging, the GPS instability was less than two nanoseconds, and the STL instability was only slightly higher at under three nanoseconds (see chart). These measurements demonstrated that STL delivers stability comparable to GNSS and does so in an indoor location where GPS signals usually cannot penetrate.
Image: NIST
STL delivers a positioning, navigation and timing (PNT) service from satellites in low Earth orbit (LEO) to back up or augment GPS and other GNSS. The evaluation by NIST confirms that users of PNT-reliant applications can obtain accurate and reliable timing without using GNSS.
“We are thrilled that NIST has performed these independent tests that confirm what we have long known, which is that STL delivers an independent timing source that is reliable and highly consistent with UTC,” said Gregory Gutt, president and CTO of Satelles. “This report complements and reinforces the findings of the U.S. Department of Transportation, which identified STL as a top-ranked PNT system in its technology demonstration report released earlier this year, and showed STL to be the only solution that demonstrated a wide-area timing capability that works indoors and out.”
In its closing days, the Trump administration issued several new policy documents affecting positioning, navigation and timing (PNT) issues.
Some have questioned the long-term impact of these, given the significant policy differences between the previous and current administrations. Yet policies in relatively non-controversial areas such as PNT are generally developed by career personnel who tend to remain in place from administration to administration. While they must adhere to the philosophical tenets of extant elected officials, these policies tend to endure longer than others.
Even if this weren’t the case, considering the wealth of other issues the new administration is grappling with, these new policies could remain in force for some time, even if the new regime ultimately decides to change them.
Several themes run through many of the documents. These include:
Space-based PNT is vulnerable and must be protected.
The first of these late-term documents to be published was the National Space Policy issued on Dec. 9, 2020. Highlights and possible impacts for the PNT community include:
A goal to “Promote and incentivize private industry” could have implications for low-Earth orbit (LEO) PNT services.
A goal to “Increase the assurance of national critical functions” could include GPS/PNT resilience.
A pledge to “Safeguard space components of critical infrastructure” undoubtedly includes GPS. The section also has ominous statements about U.S. responses to purposeful interference and tasks the Defense and Homeland Security secretaries with having those responses ready.
Another pledge to “Maintain and Enhance Space-based Positioning, Navigation and Timing (PNT) Systems” is followed by eight explanatory paragraphs, many of which repeat previous policy. One new item is a promise to invest in detection and mitigation of harmful interference. A mention is also made of the need for multiple and diverse PNT sources, and responsible use of PNT, echoing the February 2020 Executive Order on the subject. Both of the latter two mentions were in the context of critical infrastructure and mission essential functions versus the security of the nation and economy as a whole.
Congress mandated a GPS backup technology demonstration in 2017, and $10 million was subsequently provided for that purpose. Various internal government delays resulted in the project not getting underway until March 2019. It concluded about a year later.
While some people have been critical, it is important to remember the report documents 11 vendor demonstrations, not engineering tests. Technologies were demonstrated in different locations and under differing conditions.
There is no silver bullet for meeting the nation’s needs. It must be a system of systems.
Also, the amount of effort and equipment in the demonstrations depended in some cases upon infrastructure available and the amount of money the government and vendors were able to spend. This meant that at least one technology was “demonstrated” mostly by explaining the concept, and other vendors were able to only partially demonstrate their technologies.
All of that said, the report offers valuable information about how America should make its national PNT much more resilient and reliable. First, it reinforces DOT’s message that there is no silver bullet for meeting the nation’s needs. It must be a system of systems. Second, the report goes further and says what that system of system should look like: “Those technologies are LF and UHF terrestrial and L-band satellite broadcasts for PNT functions with supporting fiber-optic time services to transmitters/control segments.”
From a policy perspective, this is a huge step forward. It resolves previous ambiguity and positions the nation to establish a resilient PNT architecture, one that will do more than be a “GPS backup.” It will be an architecture that will better support current applications and better enable emerging ones like autonomy, 5G and “NextG.”
Published one hour and fourteen minutes before the end of the administration on inauguration day, this plan was mandated as part of the February 2020 Executive Order on responsible use of PNT. By taking a comprehensive look at how we can do better, it provides an interesting outline of the challenges associated with America’s current over-reliance on GPS. While not a policy or directive document, it does suggest two or three departments and agencies that might be tasked with addressing each challenge.
It also addresses the need for interference detection and monitoring, and diverse sources of PNT.
This directive was published five days before the end of the administration and replaced the previous policy, 2004’s NSPD-39.
While the old policy calls for performance monitoring of GPS signals, the new one also has investment in interference detection and monitoring as a goal.
Perhaps the most significant change in the new policy was the absence of the words “backup capability” and the lack of a mandate for DOT to lead its establishment. Yet the policy hammers home multiple times the need for more than GPS as a source of PNT. And it doesn’t abandon the idea of government involvement in making that happen.
In addition to reinforcing Executive Order 13905 on responsible use of PNT, the directive defined a new (for presidential policies) term. “Alternative PNT Service” was described as “a PNT service that has the capability to operate completely independent of, or in conjunction with, other PNT services.” The directive goes on to say that “Multiple, varied PNT services used in combination may provide enhanced security, resilience, assurance, accuracy, availability and integrity. An alternative PNT service allows a user to transition from the primary source of PNT signals in the event of a disruption or manipulation.”
And while the policy does not say the government will establish or support an alternative PNT service, it comes pretty close. One of its goals is “Invest in… as appropriate, alternative sources of PNT for critical infrastructure, key resources, and mission-essential functions.”
It goes on to task the departments of Defense, Homeland Security and Transportation with making that happen.
So “backup” is out, “alternative PNT” is in. We agree words are important and are happy to have the new words. Let’s hope the new administration will match the new words with action (as appropriate).
In a report issued on Jan. 14, the Department of Transportation (DOT) outlined the results of its GPS Backup Technology Demonstration project. As officials had previously projected, it called for a system-of-systems approach using multiple complementary technologies.
The report called for an architecture that included signals from space in the L-band, terrestrial broadcasts in the ultra high frequency (UHF) and low frequency (LF) spectra, and a fiber backbone to synchronize and feed precise time to terrestrial transmitters.
The demonstration project and report were mandated by Congress in legislation passed in late 2017 and funded in early 2018. Delays within the administration resulted in the project beginning in early 2019.
Monty Johnson of OPNT demonstrates precise time transfer through 100 kilometers of spooled fiber-optic cable. (Photo: RNT Foundation)
Demonstrations
Of 21 firms that offered to demonstrate their wares, 11 were selected. They were:
Echo Ridge LLC and Satelles Inc. Satellite-based PNT technologies using the S and L bands, respectively.
OPNT B.V. and Seven Solutions S.L. Fiber-optic time transfer using the White Rabbit Precision Time Protocol technology.
TRX Systems Inc. Dead reckoning technology with inertial measurement units and localized map matching supplemented with ultra-wideband beacons.
Hellen Systems LLC and UrsaNav. eLoran that uses LF transmissions.
Serco Inc. Medium frequency R-mode.
NextNav LLC. Metropolitan beacon system using UHF frequencies.
PhasorLab Inc. and Skyhook Wireless Inc. Both use Wi-Fi frequencies. Phasorlab uses a dedicated network of transmitters. Skyhook leverages existing Wi-Fi access points.
Five of the demonstrations were conducted at Joint Base Cape Cod, with the remainder at NASA’s Langley Research Center in Virginia.
Timing demonstrations were assessed for system:
coverage (service availability) within an “appropriate area” (wireless systems only)
accuracy and stability across an appropriate area
long-term accuracy and stability of time transfer to a fixed location
time transfer availability and accuracy to a fixed location under challenged GPS signal conditions.
Positioning was evaluated for:
coverage within a defined region
2D and 3D dynamic positioning service availability and accuracy
availability and accuracy of static positioning
long-term availability and accuracy of static positioning
long-term availability and accuracy of static positioning under challenged GPS signal conditions
DHS work referenced
The report also mentions an earlier set of demonstrations done by the Department of Homeland Security (DHS).
In December 2018, DHS’s Science and Technology Directorate performed the work through the Homeland Security Systems Engineering and Development Institute. The project “demonstrated a combination of position and timing use cases for dynamic vs. static and indoor vs. outdoor applications, along with a time-transfer use case for critical infrastructure applications.” Systems from Locata Corp, NextNav, and Satelles were evaluated.
The DoT report says that eLoran was not part of the DHS effort because of the lack of transmitters in the area. However, “DHS had previously studied eLoran performance under a Cooperative Research and Development Agreement (CRADA) with Harris Corporation and UrsaNav and had an understanding of its capabilities.”
A report of DHS’ December 2018 work is not publicly available, though DOT says it was used to inform their efforts.
The 437-page DOT report is filled to the brim with detailed information about the project, individual technologies, and demonstration results.
The Executive Summary says that, in addition to the findings from the DHS December 2018 effort (which were not listed), the DOT demonstration had four key findings:
All TRL-qualified vendors offered showed PNT “performance of value” and one showed value in all scenarios.
Neither eLoran company succeeded in the Static Basement Timing scenario.
R-mode ranging did not meet the minimum technical readiness level (TRL) of 6.
Deployment effort and coverage (infrastructure per unit area) are significant cost factors.
Addressing the needs of critical infrastructure owners and operators, the report concluded the needed “technologies are LF and UHF terrestrial and L-band satellite broadcasts for PNT functions with supporting fiber optic time services to transmitters/control segments.”
Reactions and way forward
Government officials and industry observers alike have welcomed the report, though it does leave some questions on the table.
One is about other national PNT needs. The congressional tasking was to report on GPS backup technologies for critical infrastructure and national security. The Jan. 14 report focuses on critical infrastructure needs. Information on national security requirements, some of which is classified, was provided to Congress separately by DHS and the Department of Defense.
“Economic and homeland security are sometimes considered by agencies and Congress as subsets of national security, sometimes not,” according to one analyst. “So, we don’t know if the needs of first responders, delivery services, civil government agencies, and other essential users were ever formally considered. The good news is that the combination of systems identified, if implemented and made available to all, would likely meet the needs of most.”
Other open issues are about implementing the report’s recommendations.
Some have been quick to point out that the demonstrations were to inform the government, not part of a procurement.
“If this was for an acquisition, it would have been done differently,” said one government retiree. “Rather than having vendors set up and operate the equipment, government evaluators would have been much more hands on. And they would have made every effort to do all the trials at the same location.”
Going forward, cost will also an important factor, as mentioned in the report’s key findings. “Depending on who you want to serve and where, the costs of different technologies vary by orders of magnitude,” said one provider.
Reaction from those involved with the demonstration project has been generally upbeat with praise for DOT’s effort and anticipation of more progress.
Typical were comments from Ganesh Pattabiraman, CEO at NextNav, who appreciated the real-world scenarios DOT used in the project. Regarding next steps he said, “We look forward to working with Congress on implementing the report’s recommendations.”
Speakers include Diana Furchtgott-Roth Deputy Assistant Secretary for Research and Technology; ship captains from Maersk Lines; and representatives from the National Security Council, the Maritime Administration and U.S. Coast Guard.
While GPS jamming and spoofing is a problem in many transportation and critical infrastructure sectors, it is often most visible in maritime. This is because the Automatic Identification System (AIS) used for collision avoidance and traffic management for major vessels transmits location data based on GPS inputs.
These transmissions are received by coastal networks and satellite systems. AIS data is often freely available to the public or easily accessed.
Ships in Russian waters being spoofed to inland airports, vessels in Chinese ports reporting they are inland and circling government buildings, and ships in one part of the world transmitting their location as thousands of miles away and circling in the ocean off northern California are three of the highest provide examples in recent years.
In 2019, the U.S. Coast Guard brought interference with GPS signals as an “urgent issue” to the International Maritime Organization.
In February, President Trump issued an Executive Order on responsible use of positioning, navigation and timing. This workshop is part of the federal government’s efforts, as a part of the order, to educate the public about vulnerabilities associated with over-reliance on GPA.
The 60th meeting of the U.S. Civil GPS Service Interface Committee was held Sept. 21-22, utilizing a virtual meeting platform. This was an opportunity for anyone in the world with access to a computer to attend these public meetings of the U.S. Civil GPS Program.
For readers who were unable to attend, a synopsis of the meeting is provided below. The full agenda and presentations are available for download from the GPS.gov website.
The meeting of the CGSIC is an annual event, free and open to the public, conducted to provide updates from U.S. GPS program officials and ensure effective information exchange between the U.S. government and civil GPS users. The two-day meeting is hosted by the U.S. Department of Transportation (DOT) and the Coast Guard Navigation Center (NAVCEN). DOT serves as the civil lead for GPS and chairs the CGSIC in this capacity. NAVCEN is assigned duties as Deputy Chair and Executive Secretariat for the CGSIC.
Subcommittees of the CGSIC for Timing, International Information, and Surveying-Mapping-Geosciences held meetings on Sept. 21, and a summary of these meetings was presented during the CGSIC plenary session conducted on September 22nd.
Major General John E. Shaw, Combined Force Space Component Commander, U.S. Space Command, and Commander, Space Operations Command, U.S. Space Force, provided the keynote for this year’s plenary session. This address was followed by comments from Colonel Curtis Hernandez, Director of National Security Space Policy on the National Space Council and briefings from a variety of other government agencies.
This year’s meeting was replete with briefings from all over the world including an explanation in the International Information Subcommittee of COVID-19 Tracking in South Korea from the Deputy Director of the Korea Ministry of the Interior and Safety.
Everett Hinkley from the U.S. National Forest Service spoke in the Surveying, Mapping and Geosciences Subcommittee showing how the National Remote Sensing Program supports a variety of business areas of the Forest Service including how they are tracking the spread of the Mountain Pine Beetle infestation in our nation’s forests.
The Timing Subcommittee provided an engaging presentation on the current and future plans of the National Institute of Standards and Technology’s new Network Time Services.
Presentations during the plenary session focused on the operational status of the GPS constellation and ground control system modernization, U.S. Space-Based PNT policy, GPS augmentation systems, U.S. engagement with other international GNSS providers, PNT resiliency efforts, as well as a variety of topics related to the status and progress of ongoing GPS programs in the U.S. government.
If you have suggestions for topics to include in upcoming CGSIC meetings, would like to present a topic, or if you found information from past meetings useful and would like to hear more, please contact us via our Navigation Center “contact us” form. Please be sure to select “Civil GPS Service Interface Committee (CGSIC)” from the pull-down menu.
From a GPS operational perspective, civilian non-aviation users can submit GPS-related inquiries or report signal interference or degradation to the U.S. Coast Guard Navigation Center online or to the 24-hour watch desk at 703-313-5900.
Civil aviation users within the United States should contact the Federal Aviation Administration for GPS user support. The GPS Operations Center at Schriever Air Force Base, Colorado, is the Department of Defense lead for operational issues and questions from military users of GPS.
Rick Hamilton CGSIC Executive Secretariat GPS Information Analysis Team Lead U.S. Coast Guard Navigation Center
The letter highlights what appears to be different characterizations of the engineering information in the FCC’s record, and suggests that these contrasting statements “support a careful re-examination of the bases of the Ligado Order and a stay of the decision while that occurs.”
“GPSIA appreciates your continued interest and efforts in this proceeding, and your willingness to consider whether a stay of the Ligado order may be appropriate,” the letter states. “As the record in this proceeding makes clear, sound technical analyses were conducted on Ligado’s network by DOT — a neutral third-party U.S. government expert on GPS. Further evaluation of those analyses should prompt the Commission to set aside the Ligado order so that its understanding of the DoT ABC Report can be better aligned with the authors of the report.”
Hold on Third FCC Chairmanship. In a related report, the chairman of the Senate Armed Services Committee Sen. Jim Inhofe (R-Okla.) on July 28 placed a hold on the nomination of O’Rielly to another five-year term chairing the commission.
Inhofe said he would block O’Rielly until the nominee “publicly commits to vote to overturn the current Ligado order,” according to a report from Space News.
“Over the past few months, I have sent letters, held hearings and called countless officials to highlight what we all know to be true: the FCC’s Ligado order is flawed and will lead to significant harm to our military and the thousands of individuals and businesses that rely on GPS,” Inhofe said.
Last week, 27 members of the U.S. House Agriculture Committee sent a letter to Federal Communications Commission (FCC) Chairman Ajit Pai. In it, they urged him to reconsider the FCC’s decision to allow Ligado Networks to operate a terrestrial nationwide network that the executive branch says will cause harmful interference to GPS signals for many users.
This concern and opposition from a sector not traditionally engaged in GPS or positioning, navigation and timing (PNT) issues is just one example of how the FCC’s decision — rather than putting the issue to rest — has instead recruited a whole new set of actors from across multiple sectors for the opposition.
Many observers don’t see this as surprising.
According to one observer, previously it was easy for many to assume the FCC would reject Ligado’s proposal. The entire executive branch had been vehemently opposed for years. So had aviation groups, the weather community, geospatial interests and some satellite communications concerns. With such opposition from so many important quarters, it was reasonable for many to assume they need not become involved. Now that the FCC has acted to the contrary, these interests have become well energized.
The FCC decision also empowered opponents to educate and recruit others who don’t normally think or worry about GPS and PNT issues, folks like farmers and agricultural interests.
As one insider said, “The existing opposition can now go to just about anyone in any sector and say, ‘This is going to happen and it will harm your operation. There are no ifs, ands, or buts. The FCC has decided’.”
Photo: Avalon_Studio/E+/Getty Images
Agriculture’s reliance on GPS
Agriculture is a good example. While not the sector that first springs to mind when most people think about GPS, farming has become dependent on augmented GPS for precisely and automatically driving machinery, minimizing fertilizer and pesticide use, and a wide variety of other productivity gains over pre-GPS operations.
“GPS is critically important to the commercial agriculture, mining, forestry and rural manufacturing industries. In fact, GPS has become the single most significant technological advancement for American farm equipment in the past two decades… [A 2019 RTI study] found that during planting season, if GPS were interrupted, the economic impact to the agriculture sector could amount to losses of $15 billion due to lower crop yields. Moreover, an earlier study suggested GPS-enabled precision agriculture could save farmers an estimated 10 to 15 percent in operating costs and purchased inputs. This same study estimated the benefits of GPS to precision agriculture between $10 and $17 billion.”
Department of Transportation studies have shown that high-precision GPS receivers, such as those used in agriculture, could be impacted within 3,000 meters of a Ligado transmitters. With tens of thousands of transmitters deployed in a nationwide network, this could pose a real problem for American farming.
Other sectors have also become involved in the opposition. The recently formed Keep GPS Working Coalition has members representing aviation, surface transportation, maritime, agriculture and equipment manufacturing.
This formal and public coalition, though, seems to be just the tip of the opposition iceberg.
Almost 100 dissenting organizations
According to some involved with protesting the FCC’s decision, there are nearly a hundred organizations and companies that are working in some way to have it overturned. These include multiple aviation, delivery service, agriculture, surface transportation, geospatial, weather, maritime, space and technology interests.
One sign of the influence they are having is an increase in concerns being expressed by members of Congress.
In addition to the agriculture letter, some of the most powerful recent examples are statements made during meetings of the influential House Committee on Appropriations. Rep. Ken Calvert (R-CA), ranking member of the Defense Appropriations subcommittee, spoke at length in opposition to the FCC’s action. His comments were followed in a similar vein by the vice chair of the Appropriations Committee, Rep. Peter Aguilar (D-CA).
Many of the questions being asked by the public and members of Congress alike were reflected in the letter from the Agriculture Committee members:
How did the FCC know that “its” tests were representative and valid?
Why does the FCC find that some degradation of GPS reception is acceptable?
Why did the FCC reject the executive branch’s testing criteria?
Was there a cost/benefit analysis?
The letter also asked the question that is on almost everyone’s mind: If and when there are problems, who is going to fix them?
Not surprisingly, the primary topic at the July 1 meeting of the National Space-based Positioning, Navigation and Timing Advisory Board was the Federal Communications Commission (FCC) decision on Ligado Networks.
In it Captain Sullenberger cited many of the issues the board’s vice chair, Brad Parkinson, discussed later in the meeting. Sullenberger’s statement is available here.
In his presentation, Parkinson called the FCC decision “a grave error.” He outlined his rationale in 21 information-packed slides.
Parkinson summarized his presentation up front with three points:
Repurposing the Mobile Satellite Services (MSS) radio spectrum is very high risk and brings virtually no near-term benefit to the United States.
The risks affect much more than the Department of Defense: high-value civil applications are also in jeopardy.
Any such repurposing should have been subject to a formal rulemaking process.
At the end of the presentation, the board voted unanimously to adopt the presentation, with slight modifications, as a reference document for posting on the board’s website.
The group had previously made strong recommendations to the Departments of Defense and Transportation to oppose any such action by the FCC. Both departments have done that and are continuing to do.
Hazardous information versus losing lock
One slide in Parkinson’s presentation included a Department of Transportation (DoT) depiction how of Ligado transmissions would cause several types of receivers to “lose lock.” This graphic was used in a recent DoT presentation to the FCC.
DOT briefing to FCC: “Concerns Over Ligado Order & Authorization,” June 2020. (Slide: DOT)
Heretofore DoT has usually discussed the points at which Ligado transmissions would cause a 25% increase in the noise floor for receivers. This is an important metric as tests have shown that beyond that point many receiver types begin to give hazardously misleading information. DoT officials have used the example that the 1dB limit is like putting a load limit on vehicles crossing a bridge so that the bridge never reaches its breaking point. An important consideration with a safety-of-life application like GPS.
The National Space-Based PNT Advisory Board. (Board photo)
A receiver often gives inaccurate positioning and timing data, possibly hazardously misleading information, before it “loses lock” and stops providing any information at all. It is more difficult for a receiver to “acquire lock” than to track satellites and provide information, so equipment is rarely able to function again until it moves out of the area of interference.
When asked why DoT would bother to show such information to the FCC, one official suggested that loss of lock was more in line with the criteria the Commission used in making the Ligado decision. The hope was that, by showing that even this flawed standard had significant impacts which the FCC perhaps did not fully recognize, further technical discussions and reconsiderations could be realized.
Other Topics
While discussion of the FCC’s decision took the most time in the on-line meeting, several other issues were discussed as well.
Colonel Curtis Hernandez from the National Security Council briefly described development of a new space-based PNT policy to replace NSDP-39 which was put in place by President Bush in 2004.
He was not able to provide any specifics as it is a draft and still under consideration. Answering a question, he did say that the draft policy outlined the responsibilities of various departments, including for interference detection and monitoring.
Adam Balkcum from the Office of Science and Technology Policy discussed his office’s nascent efforts to investigate non-GNSS PNT as directed by the recent Executive Order on Responsible Use of PNT. The question of whether this includes possible PNT services from low earth orbit and geostationary satellites remains an open one.
Other presenters included:
Seth Jonas of the National Security Council staff on the recent Executive Order on Responsible Use of PNT,
Andrew Hansen of the Volpe Transportation Systems Center who spoke about efforts to monitor for GPS interference, especially in the post-FCC Ligado decision environment, and
NASA’s Chris Bonniksen discussed issues with operating and funding the agency’s Global Differential GPS system.
The agenda for the meeting and presentations are available here, as will be the meeting minutes once they have been finalized.
Spectrum regulation is much like land-use zoning: certain services are kept separate to avoid disturbing the neighbors. The U.S. Federal Communications Commission (FCC) has in effect allowed Ligado to build an outdoor concert venue next to a monastery, and by way of compensation, they offer free earplugs.
GPS/GNSS signals are extremely weak and the receivers are extremely sensitive. To give some perspective, by the time they get to the GPS receiver, GPS signals are about a factor of 20 less powerful than cosmic background noise. Ligado’s spectrum was licensed for mobile satellite services (MSS) and so was not likely to interfere with GPS.
“The U.S. Federal Communications Commission (FCC) has in effect allowed Ligado to build an outdoor concert venue next to a monastery, and by way of compensation, they offer free earplugs.”
With its new, and much more valuable license, Ligado now has a legal right to build a terrestrial cellular service. Exhaustive testing over the past 10 years has repeatedly demonstrated that such a system will interfere with high-precision GPS/GNSS receivers used in surveying, timing and Earth observation. The Department of Defense (DOD) has also made strong claims that such a system will cause harm to its systems. In all cases, the effect is much like riding a bicycle at night. You can see fine until someone comes around the corner with the high beams on and blinds you.
In its earlier filings, Ligado had asked for permission to transmit at a power level of 1500 Watts. In an amazing piece of legerdemain, they convinced the FCC, but not the Department of Transportation (DOT) or DOD, that by reducing transmit powers to 10 Watts, there would be no harm. This is a stunningly erroneous claim. As you lower the transmit power, you need many more cellular base stations to cover a given area. To use an analogy from my backyard, I can install one high-flow sprinkler head to cover the entire yard or a bunch of low-flow heads, each covering a small portion. Either way, the grass doesn’t care about anything other than inches of water, and I’m going to get wet if I run across the yard. Ligado’s core argument is equally wet. Nonetheless, it has great appeal to people who don’t understand how cellular systems work.
So, moving forward and assuming the license stands, interference events will become more prevalent and GPS will be deemed “less reliable.” Because interference sources are largely untraceable, blame will rarely attach to Ligado. I expect that GNSS receiver vendors will incorporate improved filters into receivers and pass the cost along to buyers. Ligado, or more likely whoever it sells the spectrum to, will quickly move to petition for increased transmit powers to lower capital costs; after all, more base stations cost more. And so, the Visigoths have arrived, 4G in hand with a 5G label.
Logan Scott is founder and owner of Logan Scott Consulting, www.gpsexpert.net.
Leaders in the GNSS/PNT community are reacting to the Federal Communications Commission (FCC) decision to approve an order to allow Ligado Networks to deploy a low-power nationwide 5G network. The departments of Defense and Transportation have criticized the decision, concerned about interference with GPS signals.
Below are statements we have received from our readers.
Logan Scott, LS Consulting
Logan Scott
Spectrum regulation is much like land use zoning in that certain services are kept separate so as to avoid disturbing the neighbors. The FCC has in effect allowed Ligado to build an outdoor concert venue next to a monastery and by way of compensation, they offer free earplugs. GPS / GNSS signals are extremely weak and the receivers are extremely sensitive. To give some perspective, by the time they get to the GPS receiver, GPS signals are about a factor of 20 less powerful than cosmic background noise. Ligado’s spectrum is/was licensed for mobile satellite services (MSS) and so was not likely to interfere with GPS.
With their new, and much more valuable license, Ligado now has a legal right to build a terrestrial cellular service. Exhaustive testing over the last 10 years has repeatedly demonstrated that such a system will interfere with high precision GPS/GNSS receivers used in surveying, timing, and earth observation. The DoD has also made strong claims that such a system will cause harm to their systems. In all cases, the effect is much like riding a bicycle at night. You can see fine until someone comes around the corner with the high beams on and blinds you.
The FCC has in effect allowed Ligado to build an outdoor concert venue next to a monastery and by way of compensation, they offer free earplugs.
In their earlier filings, Ligado had asked for permission to transmit at a power level of 1500 Watts. In an amazing piece of legerdemain, they convinced the FCC, but not the DoT or DoD, that by reducing transmit powers to 10 Watts, there would be no harm. This is a stunningly erroneous claim. As you lower the transmit power, you need many more cellular basestations to cover a given area. To use an analogy from my backyard, I can install one high flow sprinkler head to cover the entire yard or a bunch of low flow heads, each covering a small portion. Either way, the grass doesn’t care about anything other than inches of water and I’m gonna get wet if I run across the yard. Ligado’s core argument is equally wet. Nonetheless, it has great appeal to people who don’t understand how cellular systems work.
So, moving forward and assuming the license stands, interference events will become more prevalent and GPS will be deemed “less reliable”. Because interference sources are largely untraceable, blame will rarely attach to Ligado. I expect that GNSS receiver vendors will incorporate improved filters into receivers and pass the cost along to buyers. Ligado, or more likely whoever they sell the spectrum to, will quickly move to petition for increase transmit powers so as to lower capital costs; after all more basestations cost more. And so, the Visogoths have arrived, 4G in hand with a 5G label.
John Fischer, Orolia
John Fisher. (Photo: Orolia)
At Orolia, we support the position of the DOT, DHS and DOD and the measures they are taking to protect the GNSS band. However, interference is a fact of life in this band as the GNSS signals are very weak, so additional measures must be taken for resiliency, especially for critical infrastructure. Adversarial interference is much worse than this, so a range of solutions are possible: from the simple – for example, a horizon blocking antenna that shields energy from a nearby tower – to full multi-layer defenses that include RF filtering, advanced DSP filtering/detection, alternative PNT from STL signals, atomic clock and IMU backup, and CRPA antennas. No one solution covers every case, but the problem can be managed.
Mitch Narins, Strategic Synergies
Mitch Narins
It is quite concerning when a panel of lawyers makes a decision, despite the results of years and years of studies, and over the objections of our nation’s technical and operational Position, Navigation and Timing (PNT) experts. While I have championed the need for a complementary and resilient PNT system for many, many years, one cannot dispute the worldwide benefits that GPS and other GNSS have brought — from safety, security, and economic perspectives.
As noted in the FCC’s press release, “The order also requires Ligado to protect adjacent band incumbents by reporting its base station locations and technical operating parameters to potentially affected government and industry stakeholders prior to commencing operations, continuously monitoring the transmit power of its base station sites, and complying with procedures and actions for responding to credible reports of interference, including rapid shutdown of operations where warranted.” I believe that it is imperative that GPS users, both within the Government and in the private sector, understand:
How base station location information will be disseminated, what power levels and radiation patterns will be utilized, and what recourse GPS users will have to object to the proposed location and service;
How the service will be monitored for each base station location, what systems will be used to do the monitoring, and how the monitoring information will be publicly disseminated;
How reports of interference will be filed, how and by whom they will be determined to be “credible”, how and in what timeframe will a “rapid shutdown of operations” be accomplished, and how appropriate mitigations will be identified and implemented; and
Given the importance and concern associated with this action, what special oversight mechanisms, involving civilian and military participants, should be put in place to avert potential safety, security, and economic impacts to our nation’s critical infrastructure.
While one can model, and even test problems based on the location of facilities where aircraft would be expected to be operating close to the ground (e.g., airports and heliports), one can never be sure where a medevac or other first responder helicopter may have to set down in response to an accident or incident site. In keeping with the FCC’s own press release, it is unclear how a pilot experiencing problems with GPS (if, in fact the pilot could recognize such a problem) would be able to report the issue and have it mitigated in real time to support a safety or security mission — unless all areas around all ground transmitters were mapped and first responders could request specific ones to be turned off when operations were expected in a known area. Unfortunately, the limits of these operating areas are, many times, unknown or rapidly changing (e.g., forest fires) and any delay in reaction to unforeseen events could prove detrimental to safety, security, and economic wellbeing.
Mitre conducted a test wherein small Unmanned Aerial Systems (sUAS) could detect and avoid an aircraft based on receipt of its ADS-B squits. Perhaps these ground transmitters should include ADS-B receivers and automatically go off-air if a helicopter comes within a certain distance. I have no doubt that Ligado would not appreciate this solution …
I would hope that those who disagree with this decision will seek out a means to correct this through either the legislative or judicial branches or both. Personally, I cannot see how this either “promotes the general welfare” or “provides for the common defense” (I didn’t have to go to law school to come to those conclusions). I also believe that (1) the ever growing importance and criticality of PNT services should provoke the Congress to modify the makeup of the FCC to include PNT expertise at the very top; and (2) the FCC Office of Chief Engineer needs to become an independent point of expertise akin to the Office of Inspector General to preclude undue pressure and potential political “bending” of technical analyses.
Finally, regardless of whether one agrees or disagrees with the FCC’s order, no one can possibly believe that this decade-long tale of woe is an example of governmental “best practice.” As it took the energy and significant resources from so many more important PNT initiatives, I hope that a quality/leadership body (perhaps GAO and/or a group of IGs) take up the task to do an independent “lessons learned” assessment of this decade-long tale of woe needs to be carefully examined, as it took the energy and significant resources from so many more important PNT initiatives — we should never have to go through this ever again.
Mitch Narins is the principal consultant and owner of Strategic Synergies, LLC, a technical and management consulting firm that he formed after retiring following over four decades of U.S. government service with the FCC, US Navy/Marine Corps, and the Federal Aviation Administration.
Alison Brown
Allison Brown
GPS user equipment needs to be designed to be more resilient to interference. The threat to GPS has been well understood for many years but agencies and vendors have been slow to respond to improve national resiliency against jamming threats. The President signed into law the National GPS Timing Resilience and Security Act in 2018 and on 2/12/2020 signed an Executive Order on Strengthening National Resilience through Responsible Use of Positioning, Navigation, and Timing Services recognizing “the disruption or manipulation of these services has the potential to adversely affect the national and economic security of the United States.” The onus is now on vendors and agencies to develop resilient solutions that can operate in the presence of intentional and unintentional interference. These solutions would also mitigate any potential impact from the use of adjacent bands by operators such as Ligado to deploy 5G and Internet of Things services.
Ellen Hall
Ellen Hall
Overall, the GPS industry should be encouraged to do more to protect themselves from harmful interference. While it is too late for today’s receivers, the next generation needs to introduce more resilience. I agree with the House Armed Services Committee Chairman in saying, “While I strongly support development of the world’s most robust, safe and secure network, using L-band spectrum in such close proximity to critical GPS, as Ligado’s proposal requires, carries an unacceptable risk….”
The FCC said the approval order included stringent conditions aimed at ensuring that GPS would be vulnerable to harmful interference. It seems the only way to prevent harmful interference, would be to permanently fund an oversight commission to monitor Ligado’s system. I believe only Congress can appropriate funding for this effort, therefore the FCC’s decision should be a recommendation to Congress to implement. It is not enough to leave it to a five-person committee to “encourage” that “stringent conditions” are implemented. Enforcement is crucial. Critical infrastructure should be regulated to ensure that we can cope better with “noisy neighbors.”
The five-member Federal Communications Commission (FCC) voted unanimously to approve an order to allow Ligado Networks to deploy a low-power nationwide 5G network.
The approval comes despite objections from the U.S. Defense Department (DOD), other federal agencies and major U.S. airlines, all of whom are concerned about near-band interference with GPS.
The FCC said the approval order included stringent conditions aimed at ensuring GPS would not experience harmful interference.
“After many years of consideration, it is time for the FCC to make a decision and bring this proceeding to a close,” said FCC Chairman Ajit Pai in an April 16 news release. “We have compiled an extensive record, which confirms that it is in the public interest to grant Ligado’s application while imposing stringent conditions to prevent harmful interference.”
Ligado is seeking to repurpose a swath of L-band spectrum for a 5G network focused mainly on connecting smart devices and other internet-of-things services. According to the FCC, the order will “promote more efficient and effective use of our nation’s spectrum resources and ensure that adjacent band operations, including the Global Positioning System (GPS), are protected from harmful interference.”
In response, members of both the Senate and House Armed Services Committees and other defense advocates are considering legislative action to overturn the order.
Two areas that rely heavily on the integrity of GPS signals include defense and transportation. The DOD issued a joint statement with the Department of Transportation (DOT) criticizing the FCC ruling.
“Americans rely on our Global Positioning System (GPS) each day for many things: to locate citizens in need of emergency assistance through our E-911 system, to secure our financial system, to order and receive shipments, to travel by car for work and leisure, to facilitate commercial trucking and construction work, and even to make a simple cellphone call. Our departments rely on GPS each day for all those reasons as well to coordinate tactical national security operations, launch spacecraft, track threats, and facilitate travel by air and sea. The proposed Ligado decision by the Federal Communications Commission will put all these uses of GPS at risk.”
House Armed Services Committee Chairman Adam Smith (D-Wash.) released a letter he sent to Defense Secretary Mark Esper and FCC Chairman Ajit Pai raising concerns about Ligado’s 5G network.
“While the United States must be a leader in the implementation of 5G networks, our creation of these networks must not hamper our military’s operational capacity in any way. China’s aggressive, global promotion of its 5G companies presents a considerable security challenge that must be addressed. However, Ligado’s proposal, which seeks a portion of spectrum adjacent to that used for Global Positioning Systems, poses an even larger security risk.
“The Department of Defense has been clear and direct: providing this license to Ligado would cause unacceptable operational impacts and adversely affect the military’s use of GPS. The military’s seamless use of GPS is vital to our national security. Our service members rely on GPS satellites for critical precision timing and navigation, and thousands of weapons systems are embedded with GPS signals.
“While I strongly support development of the world’s most robust, safe and secure network, using L-band spectrum in such close proximity to critical GPS, as Ligado’s proposal requires, carries an unacceptable risk that far outweighs the possibility of a 5G network.”
‘Risk of crippling’ GPS
Defense Secretary Mark Esper said via Twitter on Friday that the “Ligado proposal would needlessly imperil GPS-dependent national security capabilities. The Department continues to support domestic 5G options, but not at the risk of crippling our GPS networks. Nearly a dozen other federal agencies have joined us in opposing this proposal.”
“Although I appreciate the concerns that have been raised by certain Executive Branch agencies, it is the Commission’s duty to make an independent determination based on sound engineering. And based on the painstaking technical analysis done by our expert staff, I am convinced that the conditions outlined in this draft order would permit Ligado to move forward without causing harmful interference. For example, the draft order would authorize downlink operations at a power level that represents a greater than 99% reduction from what Ligado proposed in its 2015 application.”
Image: A-Digit/DigitalVision Vectors/Getty Images
The release also provided this background about the Ligado proposal, and the “conditions” under which the FCC decided to approve it.
In recent years, Ligado has amended its application to significantly reduce the power levels of its base stations from 32 dBW to 9.8 dBW (a reduction of 99.3%). Ligado has also committed to providing a significant (23 megahertz) guard-band using its own licensed spectrum to further separate its terrestrial base station transmissions from neighboring operations in the Radionavigation-Satellite Service allocation. As such, Ligado is now only seeking terrestrial use of the 1526-1536 MHz, 1627.5-1637.5 MHz, and 1646.5-1656.5 MHz bands. The Order is conditioned to reflect these technical requirements. It also requires Ligado to protect adjacent band incumbents by reporting its base station locations and technical operating parameters to potentially affected government and industry stakeholders prior to commencing operations, continuously monitoring the transmit power of its base station sites, and complying with procedures and actions for responding to credible reports of interference, including rapid shutdown of operations where warranted.
However, The decision “appears to ignore the well-documented views of the expert agencies charged with preserving the integrity of GPS, specifically on the critical issue of what constitutes harmful interference to users of Global Navigation Satellite Systems (GNSS),” said J. David Grossman, executive director of the GPS Innovation Alliance (GPSIA). He continued,
J. David Grossman
“GPSIA has consistently advocated for adoption of the 1-dB Standard as the only reliable mechanism that provides the predictability and certainty to ensure the continuation of the GPS success story, with the support of the Department of Defense, the Department of Transportation and numerous other federal agencies. The 1-dB Standard for radiofrequency-based services is critical for GNSS. The FCC’s press release refers to conditions placed on Ligado’s application to prevent harmful interference, and GPSIA and its members intend to carefully review the details of today’s order while continuing to vigorously advocate for promoting, protecting and enhancing GPS.”
Ligado Networks President and CEO Doug Smith issued this statement in reaction to the approval.
“Ligado thanks the Commissioners for moving promptly to approve the order regarding our applications. We greatly appreciate their unanimous support as well as the expert engineering analysis determining that a terrestrial network can be deployed in the L-band to advance our country’s economic and security interests while fully protecting GPS. Our spectrum can be very instrumental in the transition to 5G, and we look forward to utilizing satellite and terrestrial services to deploy customized private networks and deliver innovative, next-generation IoT solutions for the industrial sector.”
Positive reactions to the decision
On April 20, the FCC released a compilation of responses to the decision, all of them in support.
Attorney General Bill Barr: “I applaud FCC Chairman Pai’s proposal to make available L-band spectrum, to be used together with C-band spectrum, for deployment of advanced wireless services, including 5G. As I said in my speech at the Center for Strategic and International Studies, swift FCC action on spectrum is imperative to allow for the deployment of 5G. This is essential if we are to keep our economic and technological leadership and avoid forfeiting it to Communist China.” (Statement, 4/16/2020)
Secretary of State Mike Pompeo: “I commend Federal Communications Commission (FCC) Chairman Pai’s draft order that would release the L-Band spectrum. Quick action on this order, in conjunction with the allocation of a portion of the C-Band for 5G, is vital to our national security and will help ensure that the United States is the global leader in advanced technologies such as AI, the Internet of Things, edge computing, and the next generation of telemedicine. Accelerating the deployment of 5G is essential to our country’s growth, and global economic security.” (Statement, 4/16/2020)
Sen. Ron Johnson (WI): “In a time when connectivity is and will continue to be more important than ever, it’s great to see @AjitPaiFCC move forward with freeing up critical spectrum resources for #5G.” (Tweet, 4/16/2020)
Sen. Mark Warner (VA): “As the U.S. works to lead the world in 5G innovation and promote wider high-speed internet coverage, it’s all the more important to put our valuable mid-band spectrum to use. I urge the @FCC to follow the Chairman’s lead and approve Virginia-based @LigadoInsights’s application.” (Tweet, 4/16/2020)
Rep. Billy Long (MO): “I applaud @AjitPaiFCC and the @FCC for taking action to unlock vital L-band spectrum that has been held hostage by bureaucratic slow-walking for far too long. Jobs and 5G is a win-win for the country.” (Tweet, 4/16/2020)
Rep. Doris Matsui (CA): “I called on the @FCC to move forward with new, innovative uses of L-band spectrum to advance 5G. Glad to see the Commission take action on this front today to encourage efficient use of our spectrum.” (Tweet, 4/16/2020)
Former Rep. Bob Barr (GA): “Federal Communications Commission Chairman Ajit Pai’s decision to circulate a draft FCC Order would at long last move forward the process of opening up a segment of mid-band satellite spectrum for commercial use in 5G technology deserves praise. … If adopted by the five-member Commission headed by Pai, the draft Order would tangibly signal to the country and the world that the United States is committed to seize the leadership in deployment of 5G technology, a role China openly covets.” (Statement, 4/16/2020)
American Action Forum: “More good news from the FCC! 5G is incredibly important and this is yet another example of actions that will enable innovation in 5G and support the growing number of connected devices.” (Tweet, 4/16/2020)
American Enterprise Institute Visiting Scholar Mark Jamison: “@FCC approval of Ligado petition should accelerate 5G, bring diversity to marketplace, and increase efficient spectrum use. … Good leadership and bipartisan effort!” (Tweet, 4/20/20)
American Enterprise Institute Visiting Scholar Roslyn Layton: “Kudos @AjitPaiFCC for unlocking more vital mid-band spectrum for #5G. Record of 10 years shows @LigadoNetworks took many steps with agencies and firms to address potential issues with GPS. We must move quickly on 5G!” (Tweet, 4/16/2020)
Citizens Against Government Waste: “The FCC has the engineering expertise to determine the best use of this spectrum and whether alternative uses would cause undue interference. The adoption of the Chairman’s draft order will promote 5G and IoT development, while providing the necessary safeguards for services using adjacent bands, including GPS positioning. … The L-band would not be used at all for the foreseeable future unless the FCC takes action. Freeing up the spectrum requested by Ligado will not only expand the use of 5G, it will also help to prevent other countries, particularly China, from getting ahead of the U.S. in 5G deployment.” (Blog, 4/17/2020)
Competitive Carriers Association: “[We] commend Chairman Pai for circulating a draft order to approve Ligado’s applications, which will make much-needed mid-band spectrum, specifically L-band spectrum, available for terrestrial use. This long-awaited, positive progress comes at a critical time for all Americans, particularly those in rural areas, who are relying on mobile connections and services more than ever before. Mid-band spectrum provides real opportunities for deploying next-generation technologies, and competitive carriers are eager to access this valuable resource to expand and enhance their networks.” (Statement, 4/16/20)
Competitive Enterprise Institute: “Access to spectrum is crucial for our modern economy, connecting everything from radios, to cellphones, to satellites. But for too long, turf-wars between federal regulatory agencies have left spectrum bands largely unavailable for valuable commercial applications. Today’s FCC decision wrests spectrum away from bureaucratic waste and delivers it into the hands of people who will aide our economic recovery and resiliency in the aftermath of the COVID-19 pandemic.” (Statement, 4/16/2020)
CTIA—The Wireless Association: “We’re pleased to see that the FCC has managed to cut through the red tape to make a decision on Ligado. This multi-year process reveals the challenges at play in our nation’s spectrum policy and the need for stronger support for new commercial wireless services. We need to all learn lessons from this process and ensure that decisions on key spectrum bands like lower 3 GHz occur in a more expedited and collaborative manner.” (Statement, 4/16/2020)
FreedomWorks: “Freeing up broadband spectrum will make America a global technological leader and will lead to innovations and developments that will improve quality of life across the country. Chairman Pai and the FCC should be applauded for their work resolving these matters[.]” (Blog, 4/15/2020)
Free State Foundation: “Chairman @AjitPaiFCC has made a commendable decision to act on @LigadoNetworks’ proposal to put L-band spectrum into use for next-gen wireless services. This move takes seriously the @FCC’s responsibility and the urgent need for more commercial spectrum.” (Tweet, 4/16/2020)
Georgetown Law Institute for Technology Law & Policy Distinguished Fellow Gigi Sohn: “This decision was a long time coming, but it’s the right one. … Kudos to @AjitPaiFCC for having the fortitude to move this forward.” (Tweet, 4/16/2020)
Information Technology & Innovation Foundation: “Great to see @FCC taking steps to finally approve @LigadoNetworks waiver for terrestrial use of their spectrum. This will be a boon to industrial IoT connectivity, bringing more productivity, safety, and resiliency for users of the network.” (Tweet, 4/16/2020)
International Center for Law & Economics: “Promoting deployment of 5G & next-gen IoT devices means finding new ways for incumbents to responsibly operate in ever-closer proximity. The @FCC’s Ligado order does that. Credit to @AjitPaiFCC for finding a way fwd that promotes innovation while limiting the risk of interference.” (Tweet, 4/16/2020)
Lincoln Network: “Access to spectrum is an essential feature in any working 5G plan. Frankly, one key barrier in opening up this vital resource is government’s stronghold on ‘beachfront’ spectrum whether they own it or not. … This proceeding has been in regulatory limbo for several years due in large part to government stakeholders’ speculative interference claims regarding GPS-applications. … The FCC’s draft order in this proceeding provides enough protection for incumbents in adjacent bands, adds more competition into the 5G-IoT space, and allows consumers to have more access to broadband. Everybody wins.” (Blog, 4/16/2020)
Mercatus Center Senior Fellow Brent Skorup: “Too often new tech is stalled by FCC regulation and incumbents. Chairman Pai pledged to breathe new life into Sec. 7. It’s great to see Chairman Pai and the FCC act on that pledge, liberalize spectrum, and expedite the deployment of new wireless services.” (Tweet, 4/16/2020)
National Security Institute: “Big move by @FCC Chairman @AjitPaiFCC today to support US 5G availability. This is a key nat sec issue w/ threat posed by China + econ benefits of broad 5G deployment in US.” (Tweet, 4/16/2020)
New America Foundation’s Open Technology Institute: “Kudos to @AjitPaiFCC @FCC for again standing up to Fed agencies trying to hoard spectrum they are not using – or, in this case, which is licensed to @LigadoNetworks! A big plus for #5G wireless ecosystem if it’s built out.” (Tweet, 4/16/2020)
R Street Institute: “If you can change your business model to be more productive and profitable, without hurting anyone else, then regulations shouldn’t stand in your way. Well done, @FCC!” (Tweet, 4/16/2020)
Progressive Policy Institute: “We applaud the FCC’s ongoing efforts to accelerate the deployment of 5G. Repurposing this commercial spectrum for a mobile broadband network is another step in the right direction.” (Tweet, 4/16/2020)
Public Knowledge: “The Chairman’s proposed Order reveals how the FCC has worked to both protect incumbent GPS users while allowing for pro-competitive commercial licensing of spectrum. … Congress has entrusted the FCC to strike the proper balance between the needs of incumbents and the potential benefits to new entrants or new users, and here, the FCC gets it right. In approving Ligado’s license, the FCC has taken an important step forward in its role as the sole arbiter of spectrum disputes and, in this instance, has correctly sided on behalf of the public interest to help deliver the potential of 5G to more Americans.” (Statement, 4/16/2020)
Technology Policy Institute: “Allowing the Ligado spectrum to lie fallow would represent a waste of valuable resources that could provide substantial benefits for consumers in the form of new Internet of Things and other uses. … Failure to approve the Ligado license modifications would have the opposite effect, transferring a large block of spectrum from the commercial sector back to the government. The Commission’s action today will avoid that outcome.” (Statement, 4/16/2020)
Wireless Infrastructure Association: “WIA applauds Chairman Pai for circulating a draft order to approve Ligado’s plans to deploy a nationwide network that would primarily support 5G and IoT services. After years of diligence, study, and discussion, today’s action is further evidence that the FCC bases its decisions on science and engineering. Freeing up more spectrum, especially mid-band spectrum, is vital to 5G deployment. Ligado’s proposal offers an enormous opportunity for infrastructure investment, deployment, and connectivity for Americans across the country right when we need it most.” (Statement, 4/16/2020)
On Feb. 12, the White House released an “Executive Order on Strengthening National Resilience through Responsible Use of Positioning, Navigation, and Timing Services.”
It is gratifying to see White House attention to this issue. The increase in public awareness it brings will benefit individual users and the nation as a whole.
The order also hints at market driven solutions that could quickly improve America’s PNT resilience.
Needless delays
Unfortunately, the order fails to direct immediate action on this critical national and economic security issue. Instead it needlessly pushes most action and responsibility off for a year or more to do “more study.”
This is hard to understand as most of the “more study” has already been completed. For example, the order tells the Department of Commerce to take up to a year to examine PNT use in various sectors, and identify vulnerabilities and user needs. The Department of Homeland Security has already completed a National Risk Assessment and, according to congressional staff, has recently completed a report on user requirements mandated in 2017’s National Defense Authorization Act.
The Office of Science and Technology Policy is given a year to develop a plan to test robust and resilient non-GNSS PNT services (but is not required to actually do any testing). Congress mandated such a test program in 2017 and funded it with $10 million in 2018. After much delay, the Department of Transportation will complete the testing in May of this year.
The order gives the Department of Commerce six months to make available a time source to support critical infrastructure. For more than 60 years, the nation’s master clock has been available to users at the department’s NIST Laboratory in Boulder, Colorado.
Note the challenge has not been the clock, but that the nation has no way — other than vulnerable GPS signals — to distribute time at the needed level of accuracy to millions of critical infrastructure nodes. Government studies in 2007 and 2014 determined that the best way to do this was with a ground-based system. The Department of Transportation’s ongoing testing program is examining this issue again.
Market-driven solutions
Aside from increasing public awareness, the best thing the Executive Order does is to point a way forward for market-driven resilient PNT solutions.
The order calls for federal contracts to (in 21 months, if everyone does their jobs on time) require that vendors use existing and new resilient PNT sources.
If this eventually happens, the government could leverage its enormous influence in the market and stimulate creation of one or more commercial distribution systems for resilient, non-GNSS PNT. This is a great concept, and very much in keeping with America’s tradition of letting market forces solve some of its biggest problems.
But this solution will not spring into life on its own.
No commercial entity will invest tens of millions of dollars, or more, in a PNT system without assurance in advance of an income stream. Especially since federal contracting officers can and will waive the requirement if offerors cannot reasonably meet it.
If stimulating a market solution is the administration’s intent, it must stay actively involved and encourage the process for some time to come.
This includes complying with the 2018 law that requires establishment of at least one wireless, terrestrial, difficult-to-disrupt source to back up the timing signals provided by GPS.
Fortunately, this can be done by leveraging the free market at minimal cost and with little administrative effort.
By contracting to subscribe to a commercial service that will provide resilient PNT signals, the government need only invest a relatively small yearly sum using a fairly simple contract vehicle. Such a contracting technique has been used before with great success.
In 2007 the Federal Aviation Administration (FAA) did this as a way to establish its ADS-B aviation tracking and safety network. Once the subscription contract was let, the commercial provider was able to get financing and quickly build out the system.
Today, the FAA gets the information it needs, doesn’t have the headache of owning and maintaining a large network, and even shares in the revenue the system owner earns from selling data to other companies.
Additional leadership needed
It is important to remember that, regardless of the issue, presidential pronouncements are not enough.
In 2004, President G.W. Bush directed a number of actions to protect the nation’s critical PNT, including establishment of a GPS backup capability. While 16 years later his directive is still official executive branch policy, that mandate and many others from his order are still unexecuted.
Real improvements to PNT resilience and our nation’s security depend not on one-time pronouncements, but continued leadership focus and engagement.
This is always a challenge for initiatives driven by the White House. It will be doubly so in this case as there is no clear department leader for civil PNT issues the administration can rely on while it attends to the next issue of the day.
