The ARSR-4 is the FAA's most recent (late 80s, early 90s) addition to the "Long Range" series of radars, which are search radars with a range of at least . The Westinghouse system is solid state and has a range. In addition, 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 detection of aircraft. A Beacon system, typically an ATCBI-5, but increasingly ATCBI-6M, will be installed along with each ARSR-4. However, since the ARSR-4 is a 3D radar, it is capable of determining aircraft altitude independently of its associated Beacon (albeit less accurately).
ARSR-4 systems are installed along the borders and coastal areas of the CONUS, as well as one at the Guantanamo Bay Naval Base in Cuba, and a training site at the FAA's Mike Monroney Aeronautical Center in Oklahoma City. They are generally unmanned, being equipped with remote monitoring of both the radar data and the status of the radar's health and environment.