France Stands its Ground on 144 – 146 MHz Aeronautical Mobile Sharing Proposal

A French “annex” to its proposal to have the Aeronautical Mobile Service (AMS) share 144 – 146 with Amateur Radio doubles down on that country’s determination to secure AMS access to that spectrum, although no longer on a primary basis. The annex was submitted ahead of a European Conference of Telecommunications and Postal Administrations (CEPT) Electronic Communications Committee (ECC) Conference Preparatory Group (CPG) meeting that gets under way on August 26 in Turkey. The meeting will consider CEPT ECC positions for World Radiocommunication Conference 2019 this fall. In the annex, France counters contrary International Amateur Radio Union (IARU) assertions and insists that spectrum sharing is possible.

“France recognizes the wide range of amateur applications hosted by the 144 – 146 MHz band,” the French annex document said. “The band will remain available for all these applications after WRC-23. However a clear vision of the band segmentation per application and associated occupancy rates will be necessary for the sharing and compatibility studies carried on during the WRC-23 preparation cycle. Such studies are essential for assessing the possibilities of frequency sharing and establishing, where appropriate, the conditions that will ensure the continuity of operation and the protection of existing services.”

Since France submitted its initial proposal in June, the IARU and its Region 1 (Europe, Africa, and the Middle East) member-societies have made the matter a top priority. If the French proposal gets a thumbs up by at least 10 CEPT countries at the CPG meeting — with not more than 6 opposing — the proposal could appear on the agendas of WRC-19 and WRC-23, where a final decision will be made.

According to IARU President Tim Ellam, VE6SH/G4HUA, the French proposal provides no rationale for including the amateur band in the proposed spectrum study, and that IARU believes sharing with airborne systems would be extremely challenging and lead to constraints on the development of the Amateur and Amateur Satellite services.

“If accepted as a WRC-23 Agenda Item, this proposal would require 4 years of studies by administrations,” Ellam has stressed. “Considering the challenges of sharing spectrum with aeronautical systems, it seems inevitable that the conclusion of such studies would be that sharing with a widely used part of the amateur spectrum presents too many problems to be viable.”

In its own submission for the August CPG meeting, IARU contends that basic technical studies “show that sharing of the current Amateur Service allocation with non-safety-related [AMS] radio systems is not possible without a significant likelihood of mutual interference occurring.” IARU calls the proposal “unsound.”

“There is no need for a lengthy WRC study cycle to determine this,” IARU said, asking that 144 – 146 be withdrawn from the French WRC-23 non-safety AMS proposal.

IARU asserts that suitable alternative spectrum exists in the VHF range, but France said this view “disregards the fact that the effectiveness of studied sharing opportunities will depend upon the characteristics of the incumbent services.” France went on to say, “Use of techniques like dynamic frequency assignment, antenna treatment, power control, duty cycle control, [and] spread spectrum may be considered.”

France said the objective of studies required during the WRC-23 preparation cycle “will not be to modify the existing primary amateur allocation in the band 144 – 146 MHz but to study possible sharing of the band while ensuring the protection of amateur usage.”

At this point, the French proposal remains an ITU Region 1 matter, and action during the CEPT CPG meeting August 26 – 30 will determine whether it gains traction on the world stage

Source:ARRL