AMCP WG F

WP/39

AMCP WORKING GROUP F MEETING

(Bangkok, Thailand, November 15-27, 2001)

Agenda Item #6: Future Use of the 5 GHz Band

Considerations for Use of the 5 GHz Band

(Presented by the United States of America)

SUMMARY

This document proposes the Airport Network and Location Equipment (ANLE) which may be one candidate for operation in the 5000-5150 MHz frequency band.

1.Introduction

1.1The frequency band 5000-5250 MHz is allocated on an international basis to the Aeronautical Radionavigation Service (ARNS). Currently only the 5030-5150 MHz portion has anoperating ARNS system; namely the microwave landing system (MLS), with only the 5030-5091 MHz portion containing defined MLS channels. The aviation community is exploring expanding MLS[1] or other applications in the 5091-5150 MHz band[mw1]

1.2Two current safety objectives of the Federal Aviation Administration (FAA) are to provide more information to the pilot/cockpit, and to reduce runway incursions. The proposed application, the Airport Network and Location Equipment (ANLE), would address both of those goals, while also serving to preserve aviation spectral resources.

2.Discussion

2.1In its most basic form, ANLE is a high integrity, [mw2]wireless local area network (LAN) for aircraft on the airport surface area, combined with a connected grid of receivers acting as multilateration sensors. The former would provide the cockpit with access to appropriate information via a high-bandwidth internet-like connection. The latter would use those same transmissions to derive 3-dimensional positions of aircraft which could then be broadcast via the same data link to provide all users with situational awareness on the airport surface. Adding simple transmitters to other surface-movement vehicles would allow for the development of a high-fidelity complete picture of the airport surface environment.

2.2Considerations for use of 5 GHz:

  1. The 5000-5250 MHz band is currently protected for ARNS, though the 5150-5250 MHz portion is currently shared with the Fixed-Satellite Service. [mw3]
  2. The 5 GHz band is not well suited for long-range air-ground applications due to the high level of power required in the aircraft to overcome atmospheric attenuation. It is suitable however for short-range applications such as those associated with an airport movement area. In addition, it is possible that short-range air-ground communications, similar to those currently being studied by Eurocontrol, could also be accommodated.
  3. 5 GHz LANs are currently commercially available (though not to the specifications being proposed for ANLE). As a result, with a properly implemented priority/preemption/precedence scheme for the pilot, it may be possible to have a system that is shared by both the cockpit and commercial (e.g., internet access) users in the airport terminal. Such sharing could result in very cost-effective equipment for the aviation community, and speed regulatory acceptance of such a proposal.
  4. The industry is interested in expanding wireless services at airports. In fact, the Wireless Airport Association (WAA) has been formed to pursue this effort. Though they are currently focusing their attention on the 2.4 GHz band, exploring a shared network for safety/non-safety applications could prove beneficial to both communities. See for more detail.

3.Conclusion

3.1While ICAO standard systems such as MLS should be considered fully to ensure that their future growth is accommodated, other alternatives for use of the 5 GHz band such as ANLE should be explored in parallel.

4.0Recommendations:

4.1 The working group is invited to note the conclusions of this working paper, and encouraged to support development of innovative future aviation systems for operation in the 5091-5150 MHz band.

4.2 The working group is invited to report on the conclusions of this effort in its liaison back to working group C.

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[1] Current/future requirements for MLS are currently being studied in Europe.

[mw1]1This statement does not comport with US policy. Aeronautical Fixed Service is not a subset of Fixed-Satellite Service.

[mw2]1This term is undefined and is not intuitive from context. If this is a safety service, call it one.

[mw3]1This is unexplained. It is not intuitive what would be reallocated, why they would have to be reallocated or where they would reallocate to.