Unlike a traditional airborne radar which follows an aircraft by bouncing off of it, ADS-B (Automatic Dependent Surveillance-Broadcast) is an active communication between an aircraft and its ground-based sensors. ADS-B uses 1090MHz frequency to transmit data in standard form to ground facilities, which can then independently determine the aircraft’s location and speed. This system is mandatory for large planes in Europe and the United States. Its implementation is scheduled for 2020 and 2023.
ADS-B, which is relatively new in aviation, was first implemented in the United States in 2005. There are two major subsystems to the ADS-B function. One is the transmitter that sends data down to ground facilities, and the other is the receiver that receives data from transmitters. These subsystems allow for information such as speed, altitude, or other pertinent data to be sent to ground-based facilities. The transmitter is the central component of the system. ADS-B also has the ability to intercept position reports from aircraft. ADS-B can be used to enhance air traffic control by showing aircraft positions in real-time, which is impossible with other surveillance methods.
There are many types of ADS/B systems. The most popular is the TACAN. Other systems include FLARM, which does not work with ADS-B. The TACAN-G is more expensive and slower. The most interesting of these systems is the FLARM, a system which can be used to track gliders and other light aircraft. The system is not compatible to ADS-B making it an unsuitable choice for gliders. ADS-B provides more information, both on ground and air movements. It is far better than the other options. It's also a highly effective method of surveillance.
There are several versions available of ADS-B. The most current version is ADS-B version 3.0. Although the name sounds a bit clunky, it has been adopted by many countries including Japan, France, and the United States. ADS-B signals can also be heard from the ground as well as in the stratosphere. ADS-B, although not mandatory, is the functional equivalent to a flight data recorder and can also intercept and record position reports from other aircraft. While it has proved to be an asset for air traffic control and has caused controversy, it is also a problem. Pilots claim that the system can be dangerous, particularly for flying gliders or other light aircraft.
