While ITU regulations are determined at the WRC, each administration (country) has national regulations in place apart from the ITU regulations. This section addresses a few spectrum regulatory issues of particular note for each band used for AMT in specific administrations as reported to the ICTS.

L-Band

Cellular Interference (U.S.). While this band is currently not on any reallocation proposal, it is perceived as threatened as it is on several commercial desired spectrum lists due to its proximity to other low-band cellular spectrum. There is a Range telemetry concern that TSPI data links (Advanced Range Data System (ARDS), Common Range Integrated Instrumentation System (CRIIS), operating in 1 350-1 390 MHz, may be affected by adjacent channel interference from future commercial devices. This should be a watch item for test and training ranges that rely on GPS-based TSPI instrumentation as the susceptibility of the TSPI data link operations to cellular interference is unknown as this time. Efforts to access this susceptibility, and associated necessary protection criteria, may be needed to analyze this threat.

IMT (Region 2). The International Telecommunication Union (ITU) Radio Regulations give AMT priority over IMT in 1 435- 1 535 MHz in Region 2 (North and South America). RR 5.343. It remains high on the list of encroachment concerns for ICTS as it resides in the low band “sweet spot” for RF propagation characteristics for international mobile communications. ITU Recommendation M. 1459 is particularly relevant for AMT protection criteria.

Ligado (U.S.). The upper part of the L-band is home to several global positioning systems (GPS). Along with AMT operations below 1 525 MHz, one of these signals is potentially threatened. L1 (encrypted precision code, coarse acquisition code), at 1 575.42 MHz, could receive interference from a terrestrial data link proposed by Ligado Networks (Reston, VA) in the United States. Ligado has filed a lawsuit alleging “theft” of its L- band spectrum by the U.S. Government, but the Department of Justice has moved to dismiss the Ligado lawsuit. Several groups and companies have indicated their support for the Government’s motion.

AWS-3 Auction (U.S.). In 2014, the FCC in the United States started the process of auctioning 65 MHz of spectrum to meet the goals of the National Broadband Plan. This was the last of three auctions required for funding FirstNet, the public safety broadband network, and other services. Previous auction results had raised nearly $1.6 billion of the $7 billion needed. The AWS-3 (Advanced Wireless Services) auction generated $44.9 billion in revenue. As a result, several government users were compensated to vacate the band. AMT operations, previously in the band 1 755-1 780 MHz, were compressed into the remaining spectrum between 1 780 and 1 850 MHz. The ICTS is concerned that commercial interests may not be satisfied with the 65 MHz.

Lower S-Band

Commercial Space Launch (U.S.). In the United States, the FCC is considering potential allocation of several additional bands for commercial space launch – including 2 360- 2 395 MHz. Last year the FCC adopted rules for a new allocation in the 2 025-2 110 MHz band for space operations on a secondary basis, expanded the spectrum available for commercial space operations on a secondary basis in the 2 200-2 290 MHz band from four channels to the entire band, and adopted licensing and technical rules for space launch operations. This is a primary AMT band for flight test in the US. This has been opposed by the US DOD and Industry.

C-Band

Allocation Restrictions (Germany). In a recent decision the German administration decided that new allocations in the future will only be granted in the range 5 091-5 150 MHz, not in the range 5 150-5 250 MHz. No new or temporary allocation on a new test site will be granted in the 5 150-5 250 MHz. Current allocations in the range 5 150-5 250 MHz will remain.

Non-Federal AMT Use (U.S.). In the United States, AFTRCC has submitted a proposal to the FCC for a non-federal AMT allocation in the band 4 400-4 940 MHz with DoD support. AFTRCC would coordinate use of any such allocation, if approved, with DoD area frequency coordinators. This is not considered a “threat” since AFTRCC member companies work hand- in-glove with DoD personnel in the development of new and modified aircraft and missiles for the Department.

RADAR-Alt Interference (U.S.). In the band below 4 400-4 940 MHz, there has been major controversy regarding 5G compatibility in the band 3 700-3 980 MHz, with radar altimeters (R- Alt) operating in the band 4 200-4 400 MHz. A Federal Aviation Administration (FAA) Special Airworthiness Information Bulletin calls on R-Alt vendors and others to provide data on specific R-Alts, and to assess the need for further mitigation. Meanwhile, AT&T and Verizon have agreed to delay deployment of certain 5G operations in 3 700-3 980 MHz.

Future Spectrum Legislation (U.S.). Bills currently being considered by the U.S. Congress would require NTIA to study the 4 400-4 490 MHz band for possible future reallocation and auction. This band remains of great interest to cellular and broadband users.

Global AMT Band (All). While 5 091- 5 150 MHz is the globally harmonized band allocated for aeronautical telemetry world-wide, its utilization is a domestic issue. Global telemetry users are encouraged to make use of this AMT band. AMT use may need to co-exist with airport ground communications depending on the administration.

Upper C-Band

Unlicensed Wi-Fi (U.S.): In the United States, the FCC concluded 5 925-7 125 MHz should be utilized for unlicensed Wi-Fi and low-power devices for high data rate applications, such as wearables, augmented-reality, and virtual-reality. The band is also used for point-to-point microwave links; terrestrial microwave operators (mainly public safety and utilities) have unsuccessfully opposed the FCC’s Wi-Fi plans. While the FCC has tabled any AMT assignments/allocations in the band, DoD has studied new spectrum aggregation technologies to potentially use this band for AMT in the future.