WRC 2027 Agenda Item Details

This agenda item is to consider a new primary allocation in Region 3 to the fixed-satellite service (FSS) in the space-to-Earth direction in the frequency band 17.3 - 17.7 GHz and to the broadcasting-satellite service (BSS) in the space-to-Earth direction, while protecting existing primary services in the band. Its resolves to protect radiocommunication services to which the band is allocated on a primary basis, in particular assignments contained in Appendix 30A.

The ITU-R is invited to conduct and complete in time for WRC-27

1. studies on sharing between the FSS (space-to-Earth), the BSS (space-to-Earth) and the FSS (Earth-to-space) in order to consider the possible new allocations while ensuring the protection of existing primary allocations in the same and adjacent bands
2. consideration of the application of Region 2 non-GSO FSS epfd limits in 17.3 - 17.7 GHz in Regions 1 and 3

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

This agenda item builds on the previous conference that considered a similar topic but for Region 2. For example, compare to this web page that described the equivalent agenda item for the cycle leading up to WRC-23 for Region 2

While there was wide support for this agenda item at WRC-23, there was some sensitivity about the EPFD limits, given these were the subject of other, extensive, discussions at that conference. Note that the wording for this part of agenda item 1.4 was to "consideration of the applicability of Region 2 non-GSO FSS epfd limits... to Regions 1 and 3" rather than a wider review and that considering h) of Resolution 726 states that the epfd limits "are to be considered as a reference, without the intent of a modification at WRC-27".

Visualyse Professional and Visualyse Interplanetary can model FSS and other in-band services such as the broadcast satellite service and also those in adjacent bands such as fixed, EESS (active), radiolocation and space research. A range of modelling methodologies can be used including static and dynamic including modelling of satellite orbits. Propagation models are available for space to space, space to Earth and terrestrial paths and Visualyse Professional / Interplanetary can model both co-frequency and non-co-frequency interference scenarios. Visualyse can model interference paths that are space-space, Earth-Earth, space-Earth and Earth-space.

In addition, Visualyse EPFD can be configured to undertake EPFD analysis in this band using either the GSO FSS ES gain pattern in Recommendation ITU-R S.1428 or the GSO BSS ES gain pattern in Recommendation ITU-R BO.1443 as identified by footnote 22.5C.X (WRC-23).

We can undertake studies including analysis of sharing between the different services covered by this agenda item including FSS, BSS and other services in adjacent bands. 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.