In the mid-1950s General Electric developed a radar with a search altitude of 100,000 feet and a range of 270 miles. This radar was significant in that it was the first stacked-beam radar to enter into production in the United States. The antenna was fed signals from several feed horns arranged in a vertical stack, producing a series of horizontal beams separated vertically in space. By comparing the returns from the different feeds, altitude information could be determined without the need for a separate height-finder radar.
Designed to operate in the L-band at 1250 to 1350 MHz, the radar deployed in late 1959 and the early 1960s. The AN/FPS-7 was used for both air defense and air traffic control in New York, Kansas City, Houston, Spokane, San Antonio, and elsewhere.
In the early 1960s a modification called AN/ECP-91 was installed to improve its electronic countermeasure (ECM) capability. About thirty units were produced. Another modification was the AN/FPS-107 which also operated in the L-Band which was manufactured by Westinghouse.
In accordance with the Joint Electronics Type Designation System, the radar's "AN/FPS-7" designation represents the 7th design of an Army-Navy fixed radar(pulsed) electronic device for searching.[1][2]
