1. RR-TAG Liaison Report September 2008 IEEE 802.11-802.18
Month Year
doc.: IEEE yy/xxxxr0
September 2008
RR-TAG Liaison Report September 2008 IEEE
Date:
Authors:
Rich Kennedy, OakTree Wireless
John Doe, Some Company

2. IEEE 802.18 Proceedings This Week Update on the WP5D meeting in Korea
Developing criteria for review of IMT-Advanced contributions
Heard a presentation re: RTCA SC-202
Frank Whetten (Boeing) will present at Friday’s closing plenary

3. RTCA
RTCA, Inc. is a private, not-for-profit corporation that develops consensus-based recommendations regarding communications, navigation, surveillance, and air traffic management (CNS/ATM) system issues. RTCA functions as a Federal Advisory Committee. Its recommendations are used by the Federal Aviation Administration (FAA) as the basis for policy, program, and regulatory decisions and by the private sector as the basis for development, investment and other business decisions.

4. RTCA SC202 Issue Preview POTENTIAL COMPATIBLE EMISSIONS SOLUTION?
The RTCA “SC-202 T-PED limit” curve shown in blue is representative of the DO-160 emission limits for aviation equipment installed in an airplane. This is not the complete, accurate emissions curve, but shows the general relationship to FCC Part 15 emissions limits shown in red.
To provide some examples of why the “SC-202 T-PED limit” curve is shaped as it is:
The curve represents the maximum emissions that onboard avionics systems can tolerate and still provide their required performance.
Consider the reasons for the two “notches” in the DO-160 line:
The lower frequency notch, which runs from around 108 MHz to 137 MHz protects:
Aviation radio two-way voice and data communications systems (Pilot communications with air traffic controllers and other essential services such as meteorology and flight control) – Interference with these systems could cause aircrews to miss critical course or altitude change directions and other important communications that can add considerable confusion in already busy cockpits
Navigation receivers (Includes both distant radio beacons – weak signals – for enroute airplane navigation and critical instrument landing system receivers used to guide fully automated, “hands off” landings in near zero-zero weather) – Interference with these systems could result in important navigation errors that could reduce safe margins from both terrain and other aircraft.
The higher frequency notch runs from around 962 MHz to 1,610 MHz protects a variety of services, including in part:
Collision Avoidance system equipment (affectionately known to the crews as the “fish finder.” These sensitive receiver-transmitter systems communicate between aircraft to give pilots accurate positions of possible traffic conflicts and automatically provide collision avoidance guidance when required) – Interference with these systems could cause false avoidance commands, or an absence of a required avoidance command, that might create a hazard another aircraft.
Long range air to ground distance measuring equipment with sensitive receivers that provide crews precise position information and also interface with advanced navigation systems that provide both horizontal and vertical enroute navigation guidance – Interference with these systems could result in important navigation errors that could reduce safe margins from both terrain and other aircraft.
Several different GPS services and satellite voice communications systems with some of the most sensitive receivers of all due to the great range to the space based transponders. Interference implications are similar to those already discussed.

5. Questions? Month Year doc.: IEEE 802.11-yy/xxxxr0
Rich Kennedy, OakTree Wireless
John Doe, Some Company