Posted by John McHale WASHINGTON, 25 Sept. 2010. The Federal Aviation Administration (FAA) gave the green light for full-scale, nationwide deployment of the satellite-based surveillance system called Automatic Dependent Surveillance - Broadcast (ADS-B) following its successful roll-out at four key sites. The commissioning of the system means that air traffic controllers are now able to use the new technology to separate aircraft in areas with ADS-B coverage. Controller screens in those areas will show aircraft tracked by radar as well as aircraft equipped with ADS-B avionics, which broadcast their positions. The new system tracks aircraft with greater accuracy, integrity, and reliability than the current radar-based system. ADS-B targets on controller screens update more frequently than radar and show information including aircraft type, call sign, heading, altitude, and speed. The commissioning follows the successful deployment of ADS-B in Alaska, the Gulf of Mexico, Louisville, and Philadelphia. Those sites were chosen because they provided target-rich environments for operational testing or presented different challenges reflecting the complexity of the nation's airspace. This approach ensured that ADS-B was tested in the most extreme environments, allowing the agency to uncover and resolve any anomalies before the commissioning. Nationwide ADS-B coverage will be complete in 2013. Every part of the country now covered by radar will have ADS-B coverage. More than 300 of the approximate 800 ADS-B ground stations that will comprise the entire network have already been installed. By 2020, aircraft flying in controlled airspace in the U.S. must be equipped with ADS-B avionics that broadcast their position. The FAA is also using ADS-B technology to provide free weather and traffic information to operators who choose to equip their aircraft with avionics capable of receiving this data. This will allow pilots to view cockpit displays showing where they are in relation to other aircraft, bad weather and terrain. They will also receive flight information such as temporary flight restrictions to help them plan safe, more efficient routes. The FAA also commissioned a surveillance system specifically designed to improve safety in remote, mountainous regions. That system, called Wide-Area Multilateration (WAM), improves safety, efficiency, and capacity by allowing controllers to see aircraft not tracked by radar due to rugged terrain. WAM, which is being used in Colorado and Alaska, provides surveillance through a network of small sensors deployed in remote areas. WAM will serve as a backup to ADS-B in the event of a GPS outage in high value airspace. It will also serve as an additional source for traffic broadcasts to aircraft equipped with proper avionics.