FAA plans flexible communications

RTCA Symposium 2000

The Federal Aviation Administration plans to make its next generation of

voice communications between pilots and air traffic controllers flexible

enough to meet future digital needs and make efficient use of scarce radio

spectrum.

"As long as we always rely on voice — and we always will — we will need

spectrum," said Steve Zaidman, FAA associate administrator for research

and acquisition. Zaidman spoke at an RTCA Inc. symposium on air traffic

control modernization Wednesday in Vienna, Va.

In some regions of the country, air traffic controllers already have trouble

finding frequencies that meet air traffic control requirements, he said.

The FAA is designing its next generation communications (Nexcom) system,

which could be implemented by 2009, in response to the ever-increasing demand

for radio spectrum.

The FAA's current system of air/ground communications is the most fundamental

element of the National Airspace System for air traffic control. The FAA

uses VHF and UHF radio links to control movements at the airport, the arrival

and departure of aircraft at the terminal, and while in flight.

The demand for new air traffic control frequency assignments is expected

to grow about 3 percent per year for more than 20 years, said Marc Narkus-Kramer,

a team leader from the Center for Advanced Aviation System Development,

a federally funded research and development corporation that is operated

by The Mitre Corp.

The FAA issued a solicitation last week for the Nexcom radio, which will

use VHF Digital Link Mode 3. VDL-3 will provide multiple channels to operate

on one 25 KHz frequency assignment and will accommodate both voice and data.

It will also have the flexibility to determine how the channel resources

are applied for voice and data. An award for the radio is expected in July

2001.

FAA hopes to select a final Nexcom system developer by March 2005.

The cost of maintaining the old system is too high so it must be replaced,

Zaidman said. FAA also wants to be a leader in using digital data link,

he said.

"If we really want Free Flight, we think that it has to be digital communications

dedicated to this purpose," he said. "We know we have to make our case."

Here are some of the benefits FAA plans with Nexcom:

* Provide for spectrum relief to meet the demands for more air/ground communications.

* Lower the logistics cost of maintaining the air/ground system.

* Make a data link capability available to all classes of users.

* Reduce air/ground radio frequency interference.

* Improve systems security.

* Permit more channel control.