Saturday, January 1, 2011


The AN/SPS-48 was a long-range, 3-dimensional, air search radar which operated in the E band and F band (2 to 4 GHz) frequencies. Manufactured by ITT Corporation, the AN/SPS-48 entered service with the US Navy in 1965, installed in the USS Worden. This ship-based radar was mounted on a base that allowed for 360 degrees of rotation. The target could be located at a given azimuth. The range of the target was also identified due to the time it took the beam to go out and back to the receiver. The AN/SPS-48 was capable of detecting the height of the target above the surface of the water. Thus, the radar's central processor had the ability to place the target in an X,Y,Z, 3 dimensional space.

This radar system had a range exceeding 200 nmi (370 km) and could track targets up to 69 degrees in elevation. The AN/SPS-48E was capable of providing target range, bearing and altitude information using a frequency-scanning antenna using a range of different frequencies in E band and F band with three power modes: high, medium and low. The AN/SPS-48's antenna could rotate at 7.5 or 15 rpm. Although it was mechanically rotated to scan azimuth, beams were electronically steered to cover elevation. It could stack multiple beams in a train of pulses at different frequencies. The beams scanned different elevation areas, allowing the stack to cover up to 69 degrees of elevation. The SPS-48 was a key component of the New Threat Upgrade (NTU) and was the predecessor of the AEGIS system currently in use on Arleigh Burke-class destroyers and Ticonderoga-class cruisers.