International
Organization
Civil
Aviation
ACP-WGF31/WP-28
2014-10-06
WORKING PAPER
AERONAUTICAL COMMUNICATIONS PANEL (ACP)
THIRTYFIRST MEETING OF WORKING GROUP F
Seattle, Washington USA, October 6-10, 2014
Agenda Item 7
Development of material for ITU-R meetings
Considerations on the Preparation of CPM Text for WRC-15 Agenda Item 1.1
(Presented by India)
SUMMARY
This paper summarizes the current status of discussions on the preparation of CPM
Text for WRC-15 agenda item 1.1 and to initiate a discussion within Working Group
F for appropriate decisions to exclude future deployment IMT in the ARNS band.
ACTION
To consider the discussions on the appropriate CPM text options on WRC-15 agenda
item 1.1 that will ensure continued availability of frequency band 2 700-2 900 MHz
for ARNS
INTRODUCTION
WRC-15 Agenda item 1.1 resolves to consider additional spectrum allocations to the mobile
service on a primary basis and identification of additional frequency bands for International
Mobile Telecommunications (IMT) and related regulatory provisions, to facilitate the
development of terrestrial mobile broadband applications, in accordance with Resolution
233 (WRC-12)
Resolution-233 calls for studies on additional spectrum requirements for International
Mobile Telecommunications (IMT) and potential candidate frequency bands. The studies on
spectrum requirements should take into account technical and operational characteristics of
IMT systems and the bands currently identified for IMT, the technical conditions of their
use and the possibility of optimizing the use of these bands with a view to increasing
spectrum efficiency. The studies should also take into account the evolving needs, including
user demand for IMT and other terrestrial mobile broadband applications and the time-frame
in which spectrum would be needed.
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The study on potential candidate frequency bands should take into account sharing and
compatibility studies with services already having allocations in the potential candidate
bands and in adjacent bands, as appropriate as well as the current and planned use of these
bands by the existing services, as well as the applicable studies already performed in ITU-R.
Working Group F is invited to consider the issues in the discussion section and the
conclusions thereof while preparing its view on the most suitable decision that will ensure
exclusion of future IMT deployment in this ARNS band.
Discussions:
In Article 5 of the International Radio Regulations (RRs), the frequency band 2 700-2 900
MHz is currently allocated to the aeronautical radionavigation service (ARNS) on a primary
basis, and restricted to ground-based radar and associated transponders through RR No.
5.337, and the radiolocation service (RLS) on a secondary basis in all Regions.
Additionally, RR No. 5.423 permits the use of ground-based meteorological radars on an
equal basis to the ARNS.
Meanwhile, Chairman’s Report of the final meeting of JTG 4-5-6-7 – Document 4-5-67/715 has included the frequency band 2 700- 2 900 MHz as suitable for possible future
deployment of IMT. In this context, it may be pertinent to refer following ITU-R
documents:
a) Annex 1 to the Chairman’s Report of the final meeting of JTG 4-5-6-7 – Document
4-5-6-7/715 which summarizes the input contributions relating to frequency band 2
700-2 900 MHz from some administrations and Working Party 5D under WRC-15
Agenda Item 1.1
b) Annex 3 (Draft CPM Text for WRC-15 Agenda item 1.1) to the Chairman’s Report
of the final meeting of JTG 4-5-6-7 – Document 4-5-6-7/715 indicates that Methods
A, B and C apply for the frequency band 2 700-2 900 MHz. It was further indicated
that in case of Methods B and C Option 1 and 2 will also apply.
c) Annex 30 (Working Document towards Preliminary Draft New Report ITU-R.
[RADAR2700]) to the Chairman’s Report of the final meeting of JTG 4-5-6-7 –
Document 4-5-6-7/715, which summarizes the studies on the impact of IMT use on
radar systems in the frequency band 2 700- 2 900 MHz.
Several studies have been carried out with respect to the frequency band 2 700-2 900 MHz.
From the studies in the ITU-R Report M.2112 (2007) as well as from more recent studies, it
may be concluded that IMT systems and radars in the band 2 700-2 900 MHz operating on a
co-frequency basis are not compatible, presenting large required separation distances of
several hundreds of kilometers. In many regions IMT deployment within the band may
impose serious constraints on radar operations and future radar deployments.
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However several studies presented (Annex 30 to Chairman’s Report of the final meeting of
JTG 4-5-6-7) showed that compatibility may be achievable subject to a frequency offset and
geographic separation if certain mitigation techniques can be implemented including the
modification of mobile and radar parameters from those provided by the relevant expert
groups within the ITU. This might offer possibilities for the introduction the mobile service
into the 2 700-2 900 MHz frequency band, with due consideration of the future deployment
of radar. It should be noted that those mitigation techniques have not at this point been
determined as practical by the expert working parties.
In India, the frequency band is extensively used for primary surveillance radar, besides
meteorological use, to provide terminal and approach areas around major airports for
providing an independent surveillance coverage support to the Air Traffic Services at the
airports. Also, plans to two radars are simultaneously used at some of the major airports to
ensure comprehensive monitoring of air space. Any changes to the existing allocations in
this band are a major concern for aviation. We are closely coordinating with our national
regulator to exclude this band for future deployment of IMT.
Conclusion:
Working Group F is invited to consider the issues discussed in this paper so that consensus
amongst civil aviation administrations can be built to ensure continued availability of ARNS
band 2 700-2 900 MHz for aeronautical purposes and arrive at a most suitable method
preferably Method A for CPM Text.