Automatic dependent surveillance – broadcast

Automatic dependent surveillance – broadcast (ADS–B) is a surveillance technology in which an aircraft determines its position via satellite navigation and periodically broadcasts it, enabling it to be tracked. The information can be received by air traffic control ground stations as a replacement for secondary radar. It can also be received by other aircraft to provide situational awareness and allow self separation.

ADS–B is "automatic" in that it requires no pilot or external input. It is "dependent" in that it depends on data from the aircraft's navigation system.

ADS–B is an element of the US Next Generation Air Transportation System (NextGen),Airports Authority of India upgrade plans in line with ICAO Global Plan Initiatives and Aviation System Block Upgrade (ASBU) and the Single European Sky ATM Research (SESAR). ADS–B equipment is currently mandatory in portions of Australian airspace, the United States requires some aircraft to be equipped by 2020 and the equipment will be mandatory for some aircraft in Europe from 2017. Canada is currently using ADS-B for rather limited air traffic control, mainly in the Hudson Bay area.

ADS-B, which consists of two different services, "ADS-B Out" and "ADS-B In", could replace radar as the primary surveillance method for controlling aircraft worldwide. In the United States, ADS-B is an integral component of the NextGen national airspace strategy for upgrading and enhancing aviation infrastructure and operations. The ADS-B system can also provide traffic- and government-generated graphical weather information through TIS-B and FIS-B applications. ADS-B enhances safety by making an aircraft visible, realtime, to air traffic control (ATC) and to other appropriately equipped ADS-B aircraft with position and velocity data transmitted every second. ADS-B data can be recorded and downloaded for post-flight analysis. ADS-B also provides the data infrastructure for inexpensive flight tracking, planning, and dispatch.

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