Automatic Dependent Surveillance–Broadcast

In the United States ADS-B is an integral component of the NextGen national airspace strategy for upgrading and enhancing aviation infrastructure and operations.[12] Within the United States, the ADS-B system has the ability to provide air traffic and government-generated graphical weather information at no cost through TIS-B and FIS-B applications.Each "ADS-B Out" aircraft periodically broadcasts information about itself, such as identification, current position, altitude and velocity through an onboard transmitter.ADS-B makes flying significantly safer for the aviation community by providing pilots with improved situational awareness.Pilots in an ADS-B In equipped cockpit will have the ability to see, on their in-cockpit flight display, other traffic operating in the airspace and have access to clear and detailed weather information.[citation needed] In addition to traffic based on ADS-B reports, a CDTI function might also display current weather conditions, terrain, airspace structure, obstructions, detailed airport maps, and other information relevant to the particular phase of flight.[23] Two link solutions are used as the physical layer for relaying ADS-B position reports: universal access transceiver,[28] and 1090 MHz extended squitter.[29][30] A universal access transceiver is a data link intended to serve the majority of the general aviation community in the United States.Viable ADS-B UAT networks are being installed as part of the United States' NextGen air traffic system.The basic ES does not offer intent since current flight management systems do not provide such data (called trajectory change points).During a flight over areas without radar coverage, e.g., oceanic and polar, reports are periodically sent by an aircraft to the controlling air traffic region.[citation needed] TIS–B uplinks are derived from the best available ground surveillance sources: The multilink gateway service is a companion to TIS-B for achieving interoperability between different aircraft equipped with 1090ES or UAT by using ground-based relay stations.The service was then extended to cover some oceanic areas off the east coast of Canada including the Labrador Sea, Davis Strait, Baffin Bay, and part of the North Atlantic Tracks around southern Greenland.In line with the International Civil Aviation Organization's aviation system block upgrade plan, AAI has said that its ADS-B network will provide redundant, satellite-based surveillance where radar coverage exists, fill gaps in surveillance where radar coverage is not possible due to high terrain or remote airspace and enable it to share ADS-B data with neighboring countries.[needs update] Based on the VDL Mode 4 standards, the network of ground stations can support services for ADS-B, TIS-B, FIS-B, GNS-B (DGNSS augmentation) and point-to-point communication, allowing aircraft equipped with VDL 4-compliant transceivers to lower fuel consumption and reduce flight times.[51][52] To reduce congestion and cope with growing aircraft traffic, the Federal Aviation Administration has been developing the Next-Generation Air Transportation System (NextGen),[13] including ADS-B.Aircraft operating in the United States in the airspace classes listed below are required to carry equipment that produces an ADS-B Out broadcast.[55] Recent (April 2011) US federal legislation via House Bill for FAA re-authorization permits[56] an "equipping fund" that includes a portion for some general aviation aircraft.Airborne equipment is user-driven and is expected to be completed both voluntarily based on perceived benefits and through regulatory actions (Rulemaking) by the FAA.The cost to equip with ADS-B Out capability is relatively small and would benefit the airspace with surveillance in areas not currently served by radar.[citation needed] In December 2008, Acting FAA Administrator Robert A. Sturgell gave the go-ahead for ADS-B to go live in southern Florida.The south Florida installation, which consists of 11 ground stations and supporting equipment, is the first commissioned in the United States, although developmental systems have been online in Alaska, Arizona, and along the East Coast since 2004.The December 2008 action is in compliance with a late-term executive order from George W. Bush which mandated accelerated approval of NextGen.[62] On 14 June 2012, FreeFlight Systems and Chevron received STC for the first rule-compliant ADS-B installation in GOMEX helicopters that was awarded by the FAA.ADS-B messages can be produced, with simple, low-cost measures, which spoof the locations of multiple phantom aircraft to disrupt safe air travel.Mode-S/ADS-B identifies the aircraft uniquely among all in the world, in a similar fashion as a MAC address for a network interface controller or the International Mobile Equipment Identity (IMEI) of a GSM phone.[citation needed] However, the FAA is allowing UAT-equipped aircraft to utilize a random self-assigned temporary ICAO address in conjunction with the use of beacon code 1200.[citation needed] On 7 June 2002 the FAA published a historical overview of its decision on the ADS-B link architecture for use in the National Airspace System (NAS).By 2020, 34 nations will deploy the system, including the 17 members of the Asecna in Africa, and the Cocesna air navigation services agency in Central America.The FAA plans an evaluation in the Caribbean airspace from March 2020 until 2021, to complement the unreliable Grand Turk Island radar which allows reducing separation from 30 to 5 nmi (55.6 to 9.3 km).