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ACP-WGW01/IP-xx
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International Civil Aviation Organization
INFORMATION PAPER / ACP-WGW01/IP4
07/06/05

AERONAUTICAL COMMUNICATIONS PANEL (ACP)

NINTENTH MEETING OF THE WORKING GROUP F

Montreal, Canada15 – 19September 2008

Agenda Item 6: / Interference from non-aeronautical sources

(Presented by Andrew Knill)

SUMMARY
This paper provides information, including a short description of the issue and listing the working groups involved, on the current non-WRC spectrum issues that could potential affect aviation with Europe.
ACTION
To note the paper.
  1. Introduction

This paper provides information on the current issues within spectrum, excluding those being undertaken as part of the preparation for WRC-11, that could potentially affect aviation within Europe. It also identifies the relevant working groups where the issue is being debated within Europe and where the issue is global the relevant ITU working parties involved.

  1. Discussion

Aviation uses globally harmonised spectrum bands for its safety critical services. These bands until recently have been allocated through the Radio Regulations on an exclusive basis. However recently as the demand for spectrum, pressure has been mounting on aviation to share the spectrum allocated to aeronautical services with other users. This pressure has resulted in the sharing of Satellite spectrum (WRC-97), Sharing of DME spectrum with RNSS (WRC-03) and MLS spectrum with Telemetry (WRC-07).

Given that globally/regionally harmonised spectrum is a valuable asset the pressure on aviation to agree to greater and greater sharing is unlikely to diminish. Additionally based on current ICAO plans it is unlikely that aviations spectrum needs will diminish but is likely to increase with the introduction of Future Communications infrastructure and unmanned aerial vehicles. Therefore it is vital that aviation is actively represented at the relevant fora where spectrum issues that could affect aviation are discussed, presenting a robust case for aviations needs

The current non WRC-11 spectrum issues affecting aviation are listed below:-

GNSS Repeaters

Various industries are looking to use GNSS repeaters to enhance their business efficiency. Additionally a number of industries are looking at the use of GNSS repeaters to offer enhanced facilities to the customer. Applications proposed are for testing of installed GPS units in a factory, personal tracking through shopping centres and providing ambulance and fire services with a GNSS lock prior to departing the garage.

The problem with such devices is that they are designed to be a simple broadband amplifier operating a wide range of frequencies. They therefore have the potential to re-radiate other signals which could include primary radar and DME if the repeater is designed to operate with the new GNSS allocation at 1164-1215 MHz. It is essential, especially given that the FAA have already experienced interference, that in Europe aviation protects its use of GNSS, primary radar and DME from harmful interference from such devices.

European Group:FM44

Pseudolites

There are currently a number of proposals, such as the European Commissions MARUSE project, within Europe to use pseudolites to enhance the coverage and accuracy of the current GNSS signals. As pseudolites are proposed to operate in the current GNSS bands they have the potential if not properly regulated to cause interference to aeronautical uses of GNSS.

European Group:FM44

MSS Complementary Ground Component

Europe are currently looking at proposals to allow the use of fill in terrestrial stations within the frequency band 1535-1660 MHz to enhance the communications capacity currently provided by MSS in these bands. Within this band there are 10 MHz of uplink and Downlink spectrum reserved for Aeronautical Mobile Satellite Services which currently is lightly used however that use is likely to significantly increase with the introduction of the Single European Sky project. Therefore aviations access to these 2x10 MHz needs to be protected as does the quality/availability of the service that might be provided for aeronautical use.

European Group:SE40

Digital Broadcasting

In a number of European States broadcasters are either implementing or planning to implement digital services in the frequency bands below 108 MHz. Given the sensitivity compatibility between services above and below 108 MHz it is essential that the relevant work is carried out to determine whether there is any potential for interference from the broadcasting services below 108 MHz into the aeronautical services above 108 MHz. Should those studies show that there is potential for interference then the relevant regulations need to be developed to ensure compatibility can be achieved. This is currently the subject of a proposed ITU study question that has been rejected by ITU Study Group 5

European Group:None

ITU Group:WP 5B & 6E

Spectrum Pricing

Aviation has access to significant tracts of spectrum, a majority o which are on an exclusive basis. Additionally other government or pseudo-government organisations also hold large quantities of spectrum. In the view of many in the commercial world this spectrum is not being used efficiently. The European Commission based on work currently being undertaken in the UK is looking at whether economic principles can be applied to the use of spectrum by public sector bodies as a means to encourage them to review the way they use spectrum, improve spectral efficiency and hence release or share more spectrum with the commercial world. This approach if adopted could have significant financial impact on the aviation industry.

European Group:Radio Spectrum Policy Group – Public Use of Spectrum

3.0CONCLUSIONS

Aviation needs to remain vigilant in it’s defence of the spectrum it requires to support current and future systems, building it’s justification for such systems on robust arguments that are then supported by the timely implementation of new systems.

4ACTION BY THE MEETING

The ACP WGF is invited to: Note this paper