What is ADS-B and NextGen Technology?

What is ADS-B?
Automatic Dependent Surveillance-Broadcast, or ADS-B, is a technology implementation by the FAA to provide surveillance and improved situational awareness simultaneously to pilots and air traffic controllers.

Automatic = No interrogation by external system, and no pilot input required.

Dependent = Position dependent on own ship's navigation—Global Positioning System (GPS)

Surveillance = Provides aircraft call sign, position, type, heading, altitude, velocity vector, emergency status, plus other information.

Broadcast = Data transmitted to all ground and airborne receivers, nominally once per second.

ADS-B Frequently Asked Questions, FAA Aviation Safety publication. Questions range from "Why is the FAA deploying ADS-B technology," to "When will the ADS-B services be available in my area?"

ADS-B Fact Sheet, Federal Aviation Administration June 21, 2007, press release on ADS-B. Definition and description of the technology and its planned implementation.

ADS-B Layman Briefing, ADS-B Creates a New Standard of Aviation Safety. Definition, description, and advantages of ADS-B given in layman's terms that the average individual (without technical training) can understand.

What is NextGen?
Next Generation Air Transportation System, Federal Aviation Administration website on Next Generation Air Transportation System, or NextGen, defines the plan for a new national airspace system in the United States, and outlines its operational characteristics, implementation and benefits. The goal of NextGen is to move away from ground-based radar control and toward autonomous self-reported positioning for aircraft using satellite-based (GPS) equipment. The long-term objective is a more efficient and precise air traffic control system yielding increases in fuel economy, utility and safety.

Federal Aviation Administration publication on NextGen Implementation Download the Federal Aviation Administration publication on NextGen Implementation.

What is TIS-B?
Traffic Information Services-Broadcast, or TIS-B, provides free traffic reporting services to UAT equipped aircraft. TIS-B is a major component of ADS-B technology enabling pilots and controllers to enhance communications and increase levels of safety in the cockpit and on the ground. TIS-B allows yesterday's non-ADS-B Mode A/C/S transponder equipped aircraft that are tracked by radar to have their location and track information broadcast to ADS-B equipped aircraft. TIS-B allows UAT and 1090ES equipped aircraft to see each other,

What is FIS-B?
Flight Information Services-Broadcast, or FIS-B, provides free weather and aeronautical products to UAT equipped aircraft. FIS-B is a major component of ADS-B technology enabling pilots and controllers to enhance communications and increase levels of safety in the cockpit and on the ground.

listing of Free FIS-B Weather and Aeronautical Products. Download a listing of Free FIS-B Weather and Aeronautical Products.

What is a UAT?
Universal Access Transceivers, or UAT, are the aircraft or ground installed radio receivers and transmitters designed to utilize ADS-B services. NavWorx® offers both remote-mount and portable units for a variety of applications. Click here for more information.

The official website of ADS-B.
Surveillance and Broadcast Services, Federal Aviation Administration website for general information, Automatic Dependent Surveillance-Broadcast (ADS-B) technology, and ADS-B benefits.

The Federal Aviation Administration's role in funding ADS-B technology.
Automatic Dependent Surveillance Broadcast (ADS-B), The ADS-B system is a crucial component of the Next Generation Air Transportation System (NextGen). ADS-B is designed to improve the safety, capacity and efficiency of the national airspace system while providing a flexible, expandable platform to accommodate future air traffic growth.

What is a GBT?
Ground-Based Transceivers, or GBT, support broadcast data link services through a network of radio transmission equipment installed to support nationwide ADS-B services. Service range of each station is approximately 200 miles. GBT service requires line-of-site reception and only airports with co-located GBT will provide services while on the ground. For more information go to

Who is RTCA?
RTCA NextGen Task Force, The Radio Technical Commission for Aeronautics was organized in 1935, and today oversees the Implementation of NextGen technology for the national airspace system in the United States. RTCA develops consensus-based recommendations regarding communications, navigation, surveillance, and air traffic management system issues. RTCA functions as a Federal Advisory Committee.

What does ITT have to do with ADS-B?
ITT and ADS-B, ITT Advanced Engineering & Sciences division, a private company, is the primary government contractor for the implementation of ADS-B and NextGen technology. The company will design, deploy, and support the infrastructure that allows participants in the national airspace system in the United States to utilize the functionality of ADS-B technology.

ADS-B standards.
RTCA SC-186 ADS-B Support, Federal Aviation Administration website and discussion on the published standards for ADS-B. A variety of groups, comprised of individuals from both government and the private sector, collaborate to define system standards and application concepts and requirements of ADS-B technology.

Technical Standard Order for UAT/ADS-B.
Click here to download TSO-C154c, the Federal Aviation Administration Technical Standard Order for Universal Access Transceiver (UAT) Automatic Dependent Surveillance-Broadcast (ADS-B) Equipment Operating on Frequency of 978 MHz.

TSO-C154c Click here to download TSO-C154c