The AN/SPS-49 was a ship-based, L-band, air search radar developed by Raytheon for the US Navy. The first SPS-49 prototype was installed on board the destroyer USS Gyatt in 1965 for a test period, effectively entering service with the Navy in 1976 on board the USS Dale. Up until 1992, more than 200 units in several variants had been produced and installed in different ships. The AN/SPS-49 utilized a line-of-sight, horizon-stabilized antenna to provide acquisition of low-altitude targets in all sea states.
The AN/SPS-49 was a long-range, narrow-beam, 2-dimensional radar which operated in the frequency between 850 and 942 MHz with a range of 250 nmi (460 km). Used for early target detection, the SPS-49 was capable of performing accurate centroiding of target range, azimuth, ECM level background, amplitude, and radial velocity with an associated confidence factor to produce contact data for command and control systems. The orange-peel parabolic shape of the antenna creates a narrow 3.3°-beam to reduce the probability of detection or jamming. It can rotate at 6 rpm for long-range mode or 12 rpm in short-range mode.
Variants: AN/SPS-49(V)1, which was the first basic version; AN/SPS-49(V)2; AN/SPS-49(V)3, which was fitted with the radar video processor (RVP) interface (FC-1) (USS Long Beach); AN/SPS-49(V)4, with the RVP interface; AN/SPS-49(V)5, which was fitted out with automatic target detection (ATD) (New Threat Upgrade (NTU) ships); AN/SPS-49(V)6, equipped with double shielded cables and a modified cooling system (USS Ticonderoga (CG-47); AN/SPS-49(V)7, based on the (V)5 system, but fitted with a (V)6 cooling system (Aegis combat system); AN/SPS-49(V)8, which included the AEGIS Tracker modification kit; AN/SPS-49(V)9, with medium PRF upgrade (MPU).