What was this approval?
On April 20, 2020, the Federal Communications Commission (FCC) approved plans submitted by Ligado Networks LLC for a new 5G broadband network in the L-band portion of the spectrum, which is also used for GPS.
Ligado first submitted an application to the FCC in 2011, and through multiple amendments and a company name change in 2015, have long awaited this verdict. Ligado plans to use its portion of the spectrum to build a low-power terrestrial nationwide cellular network capable of supporting 5G and IoT (Internet of Things) services. This approval is a great accelerant for Ligado to establish its 5G network, and establish it as an American rival to Chinese 5G companies. Ligado’s system is described as a satellite and ground connectivity solution for “industrial customers via custom private networks.” The Ligado network was approved to cover 40 MHz in the 1.6 GHz band, which neighbors high-precision Global Navigation Satellite Systems (GNSS) users, like the Global Positioning System (GPS) L1 signal used for U.S. military and civil systems. Opposers believe that the Ligado services will interfere with the GPS signals that millions rely on daily.
The vote required a 3-2 majority to pass, and passed unanimously 5-0. The FCC is an independent regulatory agency, directed by five commissioners of 2 or more political parties. All commissioners are appointed by the President and confirmed by the Senate.
Why is this frequency important?
The L-band is the frequency range of 1-2GHz in the radio spectrum. Signals in this range are able to successfully pass through many physical obstructions and weather phenomena. GPS operates in the L-band range of frequencies so that its signals can penetrate most weather, vegetation, and various man-made barriers.
The more applications that exist in a band the less efficient it becomes. As Paul Selva, former Vice Chairman of the Joint Chiefs of Staff, described: “Deconfliction of band usage is necessary to ensure that certain frequencies and signal power do not disrupt adjacent functions, like a person struggling to speak over the roar of a crowd.”
The Ligado proposal was accepted under the condition that it would not interfere with other users of the L-band spectrum. In the L-band, GNSS users with designated bands include those operated by the U.S. (GPS), Russia (GLONASS), China (BeiDou) and the European Union(GALILEO). These different systems operate in various ranges within the L-band. The main concern with this case is that GPS operates with a bandwidth in the 1.575 GHz band, very close to the approved Ligado segment in the 1.6 GHz band.
Ligado’s accepted request came only after it amended its application to decrease the transmission power of its antennas by 99.3%, which the FCC will monitor by ground station levels. The FCC also authorized a 23-MHz “guard band” to further separate the Ligado signals from GNSS signals.
Some experts argue that this is not enough. J. David Grossman, executive director of the GPS Innovation alliance (GPSIA), stated that the approval of Ligado’s system “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.”
Why is there opposition to the FCC ruling?
The U.S. Department of Defense has been the most vocal organization to oppose the FCC’s decision. DoD argued that Ligado’s network would serve as a disturbance to GPS signals, possibly negating civil and military applications of GNSS networks. Officials also warned that the competing Ligado signals could render current GPS technology inadequate, forcing early upgrades for current GPS receivers that lack protection against jamming and unintentional interference, which could cost American taxpayers billions of dollars. Some have called the proposal “fundamentally a bad idea for America’s national and economic security.” Bi-partisan leaders of the House and Senate Armed Services committees penned an op-ed expressing concerns about the financial and national security risks that could come with this decision.
In a letter to Secretary of Defense Mark Esper and FCC Chairman Ajit Pai, House Armed Services Committee Chairman Rep. Adam Smith (D-WA) stated:
“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.”
Similarly, an Air Force memo warned of the added burden on military systems if this plan was approved. The memo was signed by multiple federal agencies, including: the Army, Navy, Federal Aviation Administration (FAA), Energy, and Justice departments.
Commercial entities have also expressed their disapproval of the decision. Delta Airlines, Southwest Airlines, Lockheed Martin Corp, Iridium Communications Inc, and FedEx Corp have spoken out against the FCC’s approval. The National Telecommunications and Information Administration (NTIA) opposes the approval as well.
How will this change operations for the U.S. military?
The U.S. Space Force operates the GPS system, and GPS receivers are installed on countless pieces of equipment used throughout the military. To continue to do so in a future where Ligado is operating in an adjacent frequency, the DoD may have to upgrade current military GPS receivers to modern systems that are more resistant to jamming and spoofing, though this could be through trial and error. In a February 14, 2020 memo Thu Luu, the executive agent for GPS in the Air Force, indicated that identifying and replacing impacted GPS receivers would be futile without substantial testing, software updates, and verification before an attempted implementation. Luu continued to argue that replacing government receivers would not be enough, and there is a high likelihood of defenseless interference with civil devices that the government relies on. Luu went on to express that if a practical solution is to be found to mitigate these vulnerabilities with a neighboring Ligado network, it would be “on the order of billions of dollars and delay fielding of modified equipment needed to respond to rapidly evolving threats by decades.”
What is the 5G competition?
5G is the fifth- generation technology of wireless networks. It is designed for more reliable, uniform coverage at faster speeds than current 4G service. 5G signals are difficult to successfully maintain across the country, because the same frequency ranges that work well in cities do not work well in rural areas. The spectrum requested by Ligado in the L-band is a sweet spot — which is why military applications like GPS operate in this frequency range. However, 5G signals are so strong that pre-existing systems will have a harder time receiving their own data over the roar of the 5G signals. In similar situations, other communication companies building 5G networks have had to use dual-frequency systems to reach metropolitan and rural markets to avoid this.
FCC chairman Ajit Pai cited American leadership in 5G as a motivator for this approval, and U.S. Attorney General William Barr and U.S. Secretary of State Mike Pompeo have issued statements agreeing and showing support for the FCC decision. In early 2020, Barr gave statements on the threat that Chinese technology poses to the U.S., stating: “The risk of losing the 5G struggle with China should vastly outweigh other considerations.”
There are few companies making viable 5G technologies, and Chinese technology companies are quickly gaining international support and cooperation, including close allies of the United States. By issuing this approval, U.S. officials hope Ligado can quickly produce a reliable 5G network. This will serve as an American answer to rapidly growing Chinese businesses, creating an American option to provide 5G infrastructure to allies and developing nations.
The FCC is expected to continue to make decisions that will impact U.S. companies attempting to construct 5G technology throughout 2020. 
The post What the FCC Ligado Approval Means for U.S. Military Systems appeared first on Aerospace Security.