On November 1, the Frequency Working Group of FuTURE Mobile Communication Forum held its second meeting in 2024 at Ericsson Building. This working group meeting focused on the progress of ITU-R WP5D, preparations for the WRC-27 regional conference, and the US Federal Communications Commission (FCC)'s proposed rulemaking on spectrum regulation for UAV systems. The working group also planned to jointly draft the views of the FuTURE Mobile Communication Forum on WRC-27 IMT-related topics. The meeting was co-presided by Ding Xianhua (from the State Radio Regulation of China), Chairman of the Working Group, and Wang Wei (from Ericsson), Vice Chairman of the Working Group. More than twenty representatives from member units including China Telecom, China Mobile, China Unicom and Ericsson, Huawei, ZTE, Qualcomm, Samsung, Nokia, Apple, OPPO, Xiaomi, and UNISOC attended the meeting.

Focus on ITU-R WP5D Progress

ZTE Corporation explained the progress made on WRC-27 agenda item 1.7 since the last ITU-R WP5D meeting. It focused on the key controversial issues in interference coexistence studies and IMT parameter discussions, including reverse interference studies, liaison statements with relevant contribution groups, clutter loss, interference coexistence scenarios in three frequency bands, large-scale deployment scenario parameters (Ra/Rb), and protection criteria. Controversial topics were discussed at the meeting. The participating representatives exchanged views in detail on the selection of scenarios and the setting of Ra/Rb parameters and also discussed the input text intent for the WP5D meeting in February next year.

Samsung introduced the progress of agenda item AI1.13 of ITU-R WP 5D, the joint meeting of WP5D/4C, and the main progress of agenda items AI 1.12, AI1.13, and AI 1.14 of WP4C. WP5D mainly completed the liaison statements sent to 4C, clarifying the need for WP 4C to conduct research on topics such as frequency lists, protection of IMT BS and UE, and MSS characteristics. WP5D did not reach a consensus on whether the UE included NTN, and three pfd limits for MSS on protection of IMT BS/UE. The meeting discussed the controversial topics of WP5D. The native opinion in the 5D meeting was that there should be no difference in treatment whether it was an unmodified UE or a new UE, as long as the RF requirements remained unchanged. Regarding the pfd level, the domestic preference was for Option 2, which was to calculate feasible protection for ground terrestrial IMT systems based on the calculation of aggregated pfd limits for each satellite constellation. The 5D/4C joint meeting mainly discussed the division of responsibilities of the two working groups and whether further joint meetings were needed. WP4C mainly discussed the frequency bands and functional characteristics of MSS, and had not yet started work on coexistence research. A mailing group has been organized to discuss the technical operating characteristics of MSS. Progress on AI 1.12 and AI 1.14 was relatively slow, and the proponents of the two agenda items were in competition with each other.

Nokia Shanghai Bell introduced WP5D's key controversial topics on IMT characteristics as well as suggestions for the next steps. In order to carry out the simulation modeling of coexistence research as soon as possible, it is necessary to reach a consensus on the protection criteria and IMT working parameters at the 5D meeting in February next year. For this purpose, the industry is actively considering reaching a feasible compromise with France, Russia and other countries on topics such as protection criteria and population density (including 200 MHz bandwidth) to advance corresponding work. For example, different time percentages are considered for different applications or scenarios, or other criteria such as a reduction in throughput or coverage may be adopted. Regarding population density, it is believed that it varies from country to country and could not be used alone. It can be combined with Ra/Rb (including 2 Ra options and 3 Rb options) for comprehensive research. For the AAS model, it was expected to reach an agreement with New Zealand to add analysis of NLOS or to remove the zero-forcing option for NLOS. In addition, it is also very important to promote the 200 MHz bandwidth option, because the 200 MHz bandwidth is considered to be the mainstream of 6G.

China Telecom mainly introduced the progress of IMT ATG in ITU-R and Asia-Pacific, including the progress in ITU-R CPM-1. It also introduced the progress of the research reports on IMT ground base stations supporting ATG and UAVs at the 45th, 46th and 47th meetings of ITU-R WP5D, and the current consensus on the title and scope of the research reports. Finally, it also introduced the progress and results of the questionnaire on the research of IMT-based ATG communication systems. The questionnaire was conducted at the AWG meeting. At the same time, the China Telecom had introduced the research progress and network development status of ATG in China.

Preparation Progress of WRC-27 Regional Conference

Ericsson introduced the progress of WRC preparation in each regional group, and reviewed with the conference representatives the progress of agenda items AI 1.7, AI 1.13, AI 1.12, AI 1.14 and AI 10 of CPG27-1, PT1 and PTC, and updated the discussions on preliminary views of agenda items AI 1.7, AI 1.12, AI 1.13 and AI 1.14 of CITEL PCCII.

AI 1.7 France and Germany inputted text to the European Conference of Postal and Telecommunications Administrations (CEPT) briefing document, proposed relatively negative opinions on three frequency bands, and submitted preliminary views on the CEPT. Some other countries believed that it was too early to form preliminary views on the CEPT and maintained the TBD opinion.

AI 1.13 France and Orange contributed to the protection of terrestrial IMT in PT1. Orange proposed to protect IMT from unnecessary emissions from MSS in adjacent bands and France proposed pfd limits per satellite to protect IMT. A working document has been prepared.

AI 1.12 France and Norway provided input to the development of the CEPT briefing. They proposed a consolidated preliminary CEPT view that supported one or more of the LDR MSS bands listed in AI 1.12 and allowed multiple satellite operators to share these bands instead of using them on a first-come, first-served basis.

AI 1.14 There was only one input from France, indicating that when considering large-scale deployment of IMT systems in the band of 2120-2170 MHz, allocation of this band to MSS in the space-to-Earth direction could only be considered under AI 1.13. For 2010-2025 MHz, there was no interest in considering an MSS allocation in the Earth-to-space direction under this agenda item, as the required pairing could not be established, and a possible MSS allocation in this band should be studied under AI 1.12. It was too early to reach an agreement on the preliminary CEPT position.

AI 10 Only Germany had submitted an input document containing initial comments on the structure of the CEPT briefing as well as initial positions and agenda items for the new WRC-31. Germany did not support THz as a WRC-31 AI for IMT. Some countries believed that it was too early to consider preliminary views on the WRC-31 agenda.
At the Inter?American Telecommunication Commission (CITEL), Mexico, Colombia and Peru provided new preliminary views to support the studies of AI 1.7, while the Global System for Mobile Communications Association (GSMA) provided input text for 6G and urged that this agenda item should be given high priority, taking into account the protection of existing applications. Nokia, Ericsson, and Qualcomm jointly input text for 6G. The meeting resulted in a draft of preliminary views that stressed the need to meet emerging IMT demands, and equitable access to advanced telecommunications technologies. In addition, it also included the opinion on Brazil's concerns that the potential impact of IMT in bands allocated to FSS (including 7 250-7 750 MHz (s-E) and 7 900-8400 MHz (E-s).

Canada submitted preliminary views on AI 1.12, emphasizing the need to ensure the existing applications in guard bands and in adjacent bands, such as IMT in the PCS band of 1850-1915 MHz. Canada suggested that the overlapping frequency bands in AI 1.12, 1.13, and 1.14 should be considered. Brazil, Colombia, Canada and Mexico gave their initial views on AI 1.13, and they supported studies of MSS in the IMT bands. The US Federal Communications Commission (FCC) presented a regulatory framework which was introduced by FCC, to promote collaboration between satellites and terrestrial service providers on D2D. GSMA and Mobile Satellite Services Association (MMSA) input information document to promote MSS and D2D research. Finally, new preliminary views were formed and the overlapping frequencies among three MSS agenda items were noted. Mexico, Canada, and the United States submitted preliminary views on AI 1.14, supporting studies to consider new MSS allocations to WRC-27 while ensuring the protection of existing services.

Qualcomm introduced the notice of proposed rulemaking which was released by the Federal Communications Commission (FCC) on spectrum regulation for UAV Systems. The notice included three categories of frequencies for UAV systems that the FCC was currently consulting on.

5030-5091 MHz (Aeronautical Mobile Application): This spectrum has the reliability to support unmanned aircraft systems control and non-payload communications terrestrial link system (CNPC - Control and Non-Payload Communications).

Flexible use of existing land mobile application frequency bands: The FCC is seeking comments on whether land mobile operations and UAV use could coexist or whether changes to these rules are needed.

117.975–137 MHz (Aviation VHF—Air Traffic Control Relay Frequency): To ensure the safety of the national air domain system, the US Federal Aviation Administration requires UAV operators to communicate with air traffic control (ATC) facilities when at or near airports or when operating in controlled air domain via very high frequency traffic control or advisory frequencies. FCC seeks comment on the licensing mechanism by which UAV systems operators could apply for a license from regulatory agencies (instead of a Strategic Trade Authorization (STA)) to obtain an earth station license to communicate with air traffic control facilities.

The FCC has allocated frequencies for CNPC (Command and Control Non-Payload Communications) applications and established system operating procedures for dynamically acquiring frequencies through the Dynamic Frequency Management System (DFMS). Additionally, the use of technologies such as A2X to support Detect and Avoid (DAA) was discussed, which has not yet been decided. The FCC also seeks flexibility in the use of land mobile frequency bands, requiring the types of communications, such as the communications types of mobile network operator spectrums, the command and control, telemetry, or payload (video, etc.) functions used in the required frequency bands, and the types of technologies or infrastructures needed to support such uses. The question of how to support licenses and restrict licenses has not yet been resolved. The third category concerned communications between UAV systems and air traffic control (ATC) facilities for traffic control and advisories. The FCC is seeking comments on the licensing of UAV earth stations/aircraft stations.