Air Route Surveillance Radar

The Air Route Surveillance Radar (ARSR-4) is used by Homeland defense and the Federal Aviation Administration to control airspace within and around the borders of the United States.The ARSR-4 is the FAA's newest (late 80s, early 90s) addition to the "Long Range" series of radars, search radars with a range of at least . The Westinghouse system is solid state and has a range. A Beacon system, typically an ATCBI-5, but increasingly ATCBI-6M, will be installed along with an ARSR-4. However, the ARSR-4 is capable of determining aircraft altitude independently of its associated Beacon (albeit less accurately).
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Air Route Traffic Control Center (ARTCC) radar used primarily to detect and display an aircraft's position while en route between terminal areas. The ARSR enables controllers to provide radar air traffic control service when aircraft are within the ARSR coverage. In some instances, ARSR may enable an Air Route Traffic Control Center (ARTCC) to provide terminal radar services similar to but usually more limited than those provided by a radar approach control. (FAA4)

Air route traffic control center (ARTCC) radar used primarily to detect and display an aircraft's position while en route between terminal areas. The ARSR enables controllers to provide radar air traffic control service when aircraft are within the ARSR coverage. In some instances, ARSR may enable an ARTCC to provide terminal radar services similar to but usually more limited than those provided by a radar approach control.