INTERNATIONAL TELECOMMUNICATION UNION
RADIOCOMMUNICATION
STUDY GROUPS
Delayed Contribution
Document 4-9S/UK1-E
18 September 2001
English only
Received: 18 September 2001
United Kingdom
PROPOSALS FOR MODIFICATIONS TO
PRELIMINARY DRAFT CPM TEXT (CHAPTER 4.3) ON WRC-03
AGENDA ITEM 1.25
The text below is a proposal of a structure for the draft CPM-02 element regarding WRC-03 agenda
item 1.25 (Chapter 4.3 of CPM-02 Report).
4.3
Agenda item 1.25
"to consider, with a view to global harmonization to the greatest extent possible, having due regard
to not constraining the development of other services, and in particular of the fixed service and the
broadcasting-satellite service, regulatory provisions and possible identification of spectrum for
high-density systems in the fixed-satellite service above 17.3 GHz, focusing particularly on
frequency bands above 19.7 GHz"
4.3.1
Summary of technical and operational studies, including a list of relevant ITU-R
Recommendations
A High Density application in the Fixed Satellite Service (HD-FSS) is one which operates on a
system in the FSS, deploying a high number of ubiquitous earth stations. Satellite systems can be of
any orbital type, as GSO or non-GSO, and using any of the available technologies.
High-Density applications are generally characterized as follows:
•
flexible, rapid deployment;
•
high frequency reuse
•
small antenna size;
It may not always be practicable to coordinate HD-FSS Earth stations on an individual site by site
basis. As a consequence, some administrations may require HD-FSS terminals to operate on a non
protected basis in some FSS bands, with interference mitigation techniques used to control the risk
of interference, or operation in bands not shared with other services (i.e. within some of the
exclusive FSS bands).
The studies considered concern mainly the sharing between FSS and terrestrial services, taking into
account the possible dense deployment of Earth stations of the systems operating in the FSS.
TBC
4.3.1.1
Uplink bands
Generally speaking, co-frequency sharing with terrestrial services and especially with the Fixed
Service is not possible on the same geographical area.
-2–
49-S/UK1-E
TBC
4.3.1.2
Downlink bands
Generally speaking, co-frequency sharing with terrestrial services and especially with the Fixed
Service is possible in the same geographical area with a low probability of interference to FSS. The
interference could degrade the FSS system unavailability (increases the outage time due to rain) and
the risk of interference will increase with the density of terminals deployed and certain interference
hot spots may occur. The risk of interference can be significantly reduced by application of
mitigation techniques by the FSS and the FS. The potential techniques include : ATPC for FS,
dynamic channel assignment in FSS, site shielding and positioning of FSS terminals, use of high
performance antennas by the FS and FS. Not all techniques will be feasible in all cases.
[
TBC
4.3.1.3
4.3.2
Possible candidate downlink bands not allocated to FSS (space to Earth)
Analysis of the results of studies relating to the possible methods of satisfying the
agenda item
Solutions should be found to maximise the efficiency of the use of the spectrum.
TBC
4.3.2.1
Uplink bands
See table
4.3.2.2
Downlink bands
See table
4.3.2.3
4.3.3
Bands not yet allocated to FSS service
Methods to satisfy the agenda item for consideration by WRC and the advantages and
disadvantages of each method
To satisfy the agenda item, two cases have to be considered depending on whether or not a
candidate band is already allocated to the FSS.
If a candidate band is allocated to the FSS it must be determined whether it is appropriate for
HDFSS designation.
If a candidate band is not allocated to the FSS or if the allocation to this service in the given
direction is not appropriate for HDFSS designation, an allocation to the FSS in the appropriate
direction would need to be considered.
If an allocation to the FSS is deemed appropriate for HDFSS designation, 2 methods are proposed
to satisfy the agenda item:
4.3.3.1
-
First method
Possible designation of the band for high density applications in the fixed satellite service
through a footnote in Article 5 of the Radio Regulation;
-3–
49-S/UK1-E
4.3.3.2
4.3.3.3
Second method
Possible designation of the band for high density applications in the fixed satellite service
through a Resolution.
Advantages and disadvantages of the methods
Both methods proposed would have the advantage of providing guidance to administrations when
planning their national requirements as to which bands may be suitable for HDFSS, and could also
provide any associated regulatory provisions in relation to this usage.
TBC
4.3.4
Regulatory and procedural considerations
International coordination via RR Appendix S.7 and national coordination with other services
would ensure interference free operation, but is unlikely to be practicable in most cases involving
HDFSS applications. In cases where operation FS systems together with uncoordinted HDFSS
receiving terminals is necessary in the same geographic area the use of interference mitigation
techniques could be recommended to reduce the risk of interference into the FSS.
TBD