WRC 2027 Agenda Item Details

This agenda item relates to use of 51.4 - 52.4 GHz by gateway earth stations transmitting to non-GSO systems in the FSS. The ITU-R is invited to complete by WRC-27:

1. sharing and compatibility studies with existing services, including those in adjacent bands, to allow operation of non-GSO gateways in this band
2. in particular, to consider the protection of EESS(passive) services and the conditions in Resolution 750
3. studies of sharing and protection of radio astronomy observations in 51.4 - 54.25 GHz under 4.446
4. studies regarding the protection of GSO FSS space stations from the emissions of non-GSO FSS gateway earth stations and possible inclusion of these bands in Resolutions 769 and Resolution 770

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

This frequency bands was included in those bands available for GSO systems but not non-GSO systems at WRC-19 via footnote 5.555C as part of the Q/V band package under WRC-19 agenda item 1.6. Given the development of non-GSO systems, there has been interest in using these bands for non-GSO FSS feeder links, but there remains the requirements to protect other services, such as EESS(passive) and radio astronomy.

Those with long memories will recollect a previous Resolution 130 (WRC-97) which considered "Use of non-GSO systems in the FSS in certain frequency bands" that led to the EPFD limits in Article 22.

Visualyse Professional can be used to model sharing between non-GSO FSS networks and other services, including GSO FSS, EESS(passive) and radio astronomy. It includes the rain model in Recommendation ITU-R P.618 and can be configured to have the degree of correlation of rain fade between wanted and interfering paths as used in the algorithm in Resolution 770. It can be configured to analyse the specialised EESS(passive) protection criteria and that used by the radio astronomy service.

We can undertake studies including analysis of sharing between the services covered by this agenda item, 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. We have undertaken studies of sharing between Q/V band systems including GSO and non-GSO systems for our clients and can show how our tools can be used to analyse interference into EESS as shown by our white paper.