WRC 2027 Agenda Item Details

Agenda Item: Agenda Item 1.9
Resolution(s): Resolution 411 (WRC-23)
Description of work:

This agenda item is to review Appendix 26 of the Radio Regulations in support of aeronautical mobile (OR) high frequency modernization.

The ITU-R is invited to study:

  1. the introduction of new technologies that enhance performance, including but not limited to, new classes of emission and wideband systems
  2. the definition of the relevant technical and operational characteristics and conduct sharing and compatibility studies with existing aeronautical mobile (OR) service systems and with other incumbent services that are allocated on a primary basis in the same or adjacent bands
  3. identification of any potential modifications to Appendix 26 without modifying the existing area allotments while taking into account that the current use of the narrow band systems shall remain unchanged and shall not be impacted nor precluded by any revision to Appendix 26.

WRC-27 is invited to consider the results of the above studies and take necessary actions, as appropriate.


Note that in the case of HF communications, wideband may refer to emissions wider than 3 kHz channels, and can be achieved by single or multi-carrier emissions. Appendix 26 covers use of parts of the 3 025 - 18 030 kHz band by the aeronautical mobile (OR) service, with the relevant frequency ranges in 26/1. A wide range of other services operate in this frequency range including fixed, mobile, broadcasting, amateur and amateur satellite, standard frequency and time signal and radiolocation.

Lead Working Party(s): WP 5B
Involved Working Parties: WP 3L, WP 5C, WP 6A, WP 7A
How Visualyse products can help:

Visualyse Professional can model aeronautical systems using a range of modelling methodologies including static and dynamic, and flight paths can be modelled by defining way-points of (lat, long, height) at specified times. We can also model those services in adjacent bands and both co-frequency and non-co-frequency interference paths.

How Transfinite consultants can help:

We can undertake studies including analysis of sharing between aeronautical and other systems, and identify suitable system characteristics and sharing criteria, and provide contributions and representation at ITU-R Working Parties. Using our in house Visualyse Professional we can quickly model a very wide range of systems, services and scenarios.

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