Agenda item 1.4
1.4 to consider the results of studies in accordance with Resolution 557 (WRC-15), and review, and revise if necessary, the limitations mentioned in Annex 7 to Appendix 30 (Rev.WRC‑15), while ensuring the protection of, and without imposing additional constraints on, assignments in the Plan and the List and the future development of the broadcasting-satellite service within the Plan, and existing and planned fixed-satellite service networks;
Resolution 557 (WRC‑15) – Consideration of possible revision of Annex 7 to Appendix 30 of the Radio Regulations.
There are restrictions to the deployment of satellites in the Broadcast Satellite Service (BSS) in certain orbital positions in the band 11.7-12.7GHz. This is done in order to protect both the Fixed Satellite Service (FSS) and Broadcast Satellite Service. The restrictions apply for BSS in 11.7-12.2 GHz in Region 1 and 12.2-12.7GHz in Region 2. This situation arises because the frequencies for BSS and FSS differ between Region 1, 2 and 3.
There is an FSS allocation space to Earth in 11.7-12.2 in region 2.
There is an FSS allocation space to Earth in 12.2-12.5 in region 3 and
There is an FSS allocation in 12.5-12.7GHz in Region 1 (E-s and s-E) and region 3 (space to Earth)
There is a BSS allocation in 11.7-12.2GHz in Region 3
There is a BSS allocation in 12.2-12.7GHz in region 2
There is a BSS allocation in 11.7-12.5GHz in region 1
Different regional allocations to the FSS and BSS in the 11.7-12.7 GHz frequency range cause several interregional sharing situations between these services. BSS and FSS networks from different Regions may operate simultaneously and share orbit resource in their respective Regions. The FSS in the same frequency band is not subject to orbital position limitations.
Limitations to orbital positions of BSS
|Annex 7 limitation||Region and service of interfering assignments||Region and service of impacted assignments||Frequency band||Limitation description|
|A1a||Region 1 BSS||Region 2 FSS (Atlantic)||11.7-12.2 GHz||No assignments in the Region 1 List further west than 37.2° W|
|A1b||||Region 2 FSS (Pacific)||||No assignments in the Region 1 List further east than 146° E|
|||||Region 3 BSS subject to|
RR Appendix 30
|A2a||Region 2 BSS||Region 1 FSS (Atlantic)||12.5-12.7 GHz||No modification in the Region 2 Plan further east than 54° W|
|A2b||||Region 1 BSS subject to|
RR Appendix 30
|12.2-12.5 GHz||No modification in the Region 2 Plan further east than 44° W|
|A2c||||Region 3 FSS||12.2-12.7 GHz||No modification in the Region 2 Plan further west than 175.2° W|
|||||Region 1 BSS subject to|
RR Appendix 30
|||||Region 1 FSS (Pacific)||12.5-12.7 GHz|||
|A3a||Region 1 BSS||Region 2 FSS||11.7-12.2 GHz||No assignments in the Regions 1 and 3 List outside specific allowable portions of the orbital arc between 37.2° W and 10° E |
|A3b||||||||Maximum e.i.r.p. of 56 dBW for assignments in the Regions 1 and 3 List at specific allowable portions of the orbital arc between 37.2° W and 10° E |
|A3c||||||||Maximum power flux-density of −138 dB(W/(m2 · 27 MHz)) at any point in Region 2 by assignments in the Regions 1 and 3 List located at 4° W and 9° E|
|B||Region 2 BSS||Region 2 BSS subject to|
RR Appendix 30
|12.2-12.7 GHz||Required agreement of administrations having assignments to space stations in the same cluster when an administration may locate a satellite within this cluster|
A revision or elimination of the orbital position limitations would allow BSS additional orbital resources.
The limitations are independent of each other. The deletion of multiple limitations has no cumulative effect.
The planning for services within each region has tended to be done independently. That is, within any particular region the use of frequencies within the same service (FSS or BSS) will be co-ordinated as they have the same general reception area.
The satellites of different services in different regions (continents) have different intended catchment reception areas. Technically this gives rise to the potential for the same frequency to be used from the same orbital position aimed at two different locations. This had not been done in the past. This agenda item seeks to make more efficient use of the radio spectrum by considering "cross-region" situations which should technically be possible.
In most instances the issue concerns reception of signals from satellites. Generally satellite dishes can resolve signals with a 3 degree separation as seen from the location on earth. The signal level from satellites should be sufficiently low on the areas of earth not intended for reception. If that is the case there will not be interference even if the same frequency is used.
There is a single method proposed (Method B) for this agenda item
IRL can support the relaxation of the orbital locations in accordance with the CEPT position and the single CPM Method.