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Opinion: GPS Has Big Problems; Ligado Is Not One Of Them

Daniel S. Goldin July 09, 2020

Credit: U.S. Government For the past nine months, I have worked with world-class experts to study a longstanding request from Ligado Networks to create a ground-based 5G network using L-band spectrum. We found that L-band paired with C-band will accelerate the deployment of U.S. 5G and help counter China’s 5G ambitions without causing harmful interference to GPS. The testing record proves it and is further corroborated by the recent release of internal statements from Pentagon spectrum experts.

On April 20, the U.S. FCC announced approval of Ligado’s application to use the L-band spectrum between 1 and 2 GHz for a terrestrial 5G network providing cellular and internet-of-things data services. But Pentagon GPS advocates have enlisted the help of the Senate and House Armed Services committees to include amendments to the fiscal 2021 defense authorization bills that would empower the Defense Department to undermine the FCC’s unanimous, bipartisan decision on Ligado. If the respective Commerce committees do not assert jurisdiction over the FCC and blunt these amendments, this overt power move by the Pentagon could be complete.

• See also: Opinion: Why GPS Is Lagging The Competition And What To Do About It

While military bureaucracy claims it is committed to protecting GPS, it has neglected serious risks for decades. Excessive cost, timeline overruns and improperly filtered GPS receivers are tolerated, while the Pentagon maligns Ligado’s harmless 9.8-watt signal (a power level set by the FAA with a huge 23 MHz guard band) as a grave risk. Ironically, the Pentagon’s preoccupation with Ligado may be what finally brings proper attention to GPS mismanagement. The truth is the system has been vulnerable for a long time, endangering the troops who depend upon it. Congress has attempted to hold the Defense Department and the Position, Navigation, and Timing (PNT) community accountable, but GPS stakeholders have resisted. How bad is it? Consider:

• In 1996, then-Vice President Al Gore announced a plan to modernize GPS. In 1997, the Defense Department began developing a jam-resistant military satellite signal called M-Code, with the support of Congress and the president. After 23 years, the program is still 15 years from completion.
• President Donald Trump’s fiscal 2020 budget directs the Pentagon to transition approximately one million military GPS receivers to M-Code military receivers, but this will not occur until 2035 at the earliest—the one million M-Code chips necessary have not been made yet.
• There are now 24 M-Code-capable satellites on orbit but no compatible receivers. Further, eight of 24 M-Code satellites have been in orbit for 11-15 years, well beyond their 7.5-year design life. Some will fail or be retired before they are ever used for military operations.

Meanwhile, China started deployment of BeiDou-3 satellites in 2015 and has launched 30 satellites in five years, enabling worldwide operations in June. GPS embarked on its Phase 3 program in 1997, launched three GPS III satellites and hopes to complete the program by 2034.

A 40-year span from problem identification to problem solution is unacceptable and requires an examination of the legacy power structures behind such mismanagement. The PNT Advisory Board is composed of seasoned members of the GPS community serving before and after the senior U.S. leaders they advise come and go. What is the purpose of an advisory board with such continuity if not to help decision-makers avoid the negligence described above?

Decision-makers deserve complete information. The Pentagon’s top leaders put the country first without regard for bureaucratic agendas. However, their advisors on PNT/GPS have provided them with incomplete information, claiming Ligado is a problem and GPS is not, when the opposite is true. In my 58 years working on science, technology and U.S. national security, I have never seen an issue of such importance so beset by misinformation as the Ligado case—nor have I seen such complacency in a program as vitally important as GPS.

Such challenges will define how we as a nation respond to the increasingly common technology and national security decisions ahead. Either we will grind to a near-halt debating facts to advance internal agendas, or we will make evidence-based policy decisions to counter formidable threats to our national security and economy. I have confidence that the leaders of the Defense Department and our Armed Services committees—when presented with whole information on critical issues like Ligado, 5G and GPS—will discern the best way forward to protect our nation. 

Daniel S. Goldin is an engineer who served as NASA administrator under three U.S. presidents from 1992 to 2001. He has no financial affiliation with Ligado Networks. 

The views expressed here are author's and are not necessarily those of Aviation Week.