The AN/SPQ-9B X-band pulse-Doppler radar

The AN/SPQ-9B radar. (Photo: Northrop Grumman)

Military Aerospace Electronics reports, “DRS Laurel to build missile-defense radar systems to protect Navy surface warships from anti-ship missiles”,

U.S. Navy missile-defense experts are asking the DRS Laurel Technologies segment of Leonardo DRS in Johnstown, Pa., to provide AN/SPQ-9B shipboard anti-ship missile defense (ASMD) radar systems to help protect U.S. Navy surface warships from enemy anti-ship missiles.

Officials of the Naval Sea Systems Command in Washington announced a $8.7 million order to DRS Laurel last month to build AN/SPQ-9B radar systems and support equipment.

Bertholf class NSCs mount the AN/SPQ-9B and I suspect this order may include the system for NSC#11. It is one of the things that has made them better equipped than the Littoral Combat Ships. I had been under the impression the AN/SPQ-9B was a fire control radar, it is associated with weapon systems, but reading the description I decided to look for a better information and found the Navy’s description here.

The AN/SPQ-9B is an X-Band, pulse Doppler, frequency agile radar which was designed specifically for the littoral environment. It has a very high clutter improvement factor supporting a very low false track rate in the littorals and in high clutter environments.

The AN/SPQ-9B scans out to the horizon and performs simultaneous and automatic air and surface target detection and tracking of low flying Anti-Ship Cruise Missiles (ASCMs), surface threats and low/slow flying aircraft, UAVs and helicopters.

It now almost 30 years old, but is apparently still being upgraded and put on new construction.

The radar is installed on CVN-68, LPD-17, CG-47, WMSL-750, LHD-1 and LHA-6 ship classes. The radar is also to be installed on DDG-51 class, DDG 39, 41, 42 (AUS), DDG AMOD, CG MOD (CG 63 and follows). CVN-68, DDG-51, LPD-17, CG-47, LHD-1, LHA-6 ship classes will receive PDD (periscope detection and discrimination–Chuck) Upgrade.

I have seen nothing to indicate the OPCs will have this system.

U.S. Coast Guard Cutter Midgett (WMSL 757) sits anchored near Malé, Maldives, on Sept. 24, 2022. The cutter spent several days in the Maldives for a port-call. (U.S. Coast Guard photo by Petty Officer Steve Strohmaier)

In the photos, the AN/SPQ-9B is visible on the forward side of the mast near the top. The multimode radar, the Hensoldt TRS-3D (AN/SPS-75) is higher and on the aft side of the mast. The multimode radar is used for helicopter control, so it needs to look aft.

US Coast Guard cutter Munro transits the Taiwan Strait with US Navy destroyer USS Kidd in August. US Navy

3 thoughts on “The AN/SPQ-9B X-band pulse-Doppler radar

  1. The picture you have is of the SPQ-9A which was part of the Mk86 gun fire control system installed initially on the DD-963 class and had a reflector type antenna in a radome. As described in the US Navy fact file you linked to, as part of the development of the SPQ-9B, a lightweight planar antenna was developed as a sensor for anti-ship missile defense. This is installed on several classes of naval ships including CVN’s, LHD’s and the Flight III DDG’s. An image of this antenna is at

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