WRC 2027 Agenda Item Details

Agenda Item: Agenda Item 1.1
Resolution(s): Resolution 176 (Rev. WRC-23)
Description of work:

This agenda item relates to the technical and operational conditions for the use of parts of Q/V band for aeronautical or maritime Earth Stations in Motion (A-ESIMs and M-ESIMs), in particular 47.2 - 50.2 GHz and 50.4 - 51.4 GHz.

Studies requested of the ITU-R include:

  1. the spectrum needs and technical operational characteristics of A-ESIMs and M-ESIMS that would operate within the FSS in these bands
  2. sharing and compatibility between A-ESIMs and M-ESIMs and stations in primary service in these bands and passive services in adjacent bands
  3. other, regulatory related studies

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


This builds upon previous conferences that also had agenda items related to ESIMs, such as 1.15 and 1.16 as discussed at WRC-23 which covered lower frequency bands, such as those in Ku and Ka bands, for example, see Resolutions 121 and 123 which include PFD limits that must be met to protect terrestrial services.

Note that after much discussion this agenda item includes A-ESIMs and M-ESIMs communicating with both GSO and non-GSO systems but that land ESIMs were not included as that could be considered a national regulatory task.

Q/V band could be useful for A-ESIMs in particular as they would operate above the rain clouds that can constrain operation at ground level.

These bands are the Earth-to-space direction, as the space-to-Earth direction should be unaffected by the receiver being an ESIM.

Lead Working Party(s): WP 4A
Involved Working Parties: WP 3M, WP 4C, WP 5A, WP 5B, WP 5C, WP 5D, WP 7B, WP 7C, WP 7D
How Visualyse products can help:

Visualyse Professional can model the ESIMs operating both on aircraft and vessels and other services in the frequency range Q/V band (and adjacent bands) such as the GSO FSS, fixed, mobile, space research, aeronautical radionavigation, EESS (active) services. A range of modelling methodologies can be used including static and dynamic including modelling of satellite orbits, both GSO and non-GSO. Propagation models are available for space to space, space to Earth and terrestrial paths and Visualyse Professional can model both co-frequency and non-co-frequency interference scenarios.

Note that Visualyse Professional was used in previous WRC cycles to undertake studies of ESIMs under other agenda items and assisted in developing regulations approved at WRC-23. A White Paper that describes modelling ESIMs under Resolution 169 using Visualyse Professional is available from our web site

How Transfinite consultants can help:

We can undertake studies including analysis of sharing between the different services covered by this agenda item including ESIMs, GSO & non-GSO FSS, fixed, mobile, space research, aeronautical radionavigation and EESS services. We can help 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.

Previous Next