Air Route Surveillance Radar

The Air Route Surveillance Radar is a long-range radar system. It is used by the United States Air Force and the Federal Aviation Administration to control airspace within and around the borders of the United States.

The ARSR-4 is the FAA's most recent (late 1980s, early 1990s) addition to the "Long Range" series of radars. It is a solid state Westinghouse system with a range. The ARSR-4 features a "look down" capability that enables the radar to detect aircraft attempting to elude detection by flying at low altitudes, advanced clutter reduction via hardware and software post-processing, and enhanced poor-weather object detection. A beacon system, the ATCBI-6M (a monopulse system), is installed along with each ARSR-4. However, since the ARSR-4 has 3D capabilities, it can determine altitude independently of its associated beacon (albeit less accurately).

ARSR-4 systems are installed along the borders and coastal areas of the contiguous United States, Guantanamo Bay Naval Base in Cuba, the municipality of Yigo on Guam, and a training site at the FAA's Mike Monroney Aeronautical Center in Oklahoma City. They are generally unmanned, and are equipped with remote monitoring of both the radar data and the status of the radar's health and environment. It has expanded to additional sites throughout the entire contiguous US (or CONUS). Provided by Wikipedia