It formerly served in a complementary role aboard Aegis cruisers with the AN/SPY-1 but the systems are currently being removed during routine upgrade with no replacement.
First tested in 1965 aboard USS Gyatt and introduced in 1975, the AN/SPS-49 operates in the 851–942 MHz, or L-, band and has a range of 256 nautical miles (474 km).
The orange-peel parabolic shape of the antenna creates a narrow 3.3°-beam to reduce the probability of detection or jamming.
[1] Default is at 12 rpm for the AN/SPS-49A(V)1, to provide more frequent scans against incoming missiles.
The output stage of the transmitter in all variants uses a two-cavity klystron amplifier.