Country of originUnited States
FrequencyX band
Range200 mi (320 km)

The AN/SPY-3 is an active electronically scanned array radar manufactured by Raytheon and designed for both blue-water and littoral[1] operations.


The Aegis battle management system began with the AN/SPY-1 Passive electronically scanned array radar, intended to deal with an aircraft threat. Later repurposed to allow for Ballistic Missile Defense search and track.


Diagram of AN/SPY-3 vertical electronic pencil beam radar conex projections

X band functionality (8 to 12 GHz frequency range) is optimal for minimizing low-altitude propagation effects, narrow beam width for best tracking accuracy, wide frequency bandwidth for effective target discrimination, and the target illumination for SM-2 and Evolved Sea Sparrow Missiles (ESSM). The X-band has, in general, favorable low-altitude propagation characteristics, which readily support the horizon search functionality of the AN/SPY-3. A large operating bandwidth is required to mitigate large propagation variations due to meteorological conditions.[2]

The system uses commercial off the shelf (COTS) computers and has reduced manning requirements for operation and maintenance. A number of operation and maintenance functions can be completely automated.[2] Commercial IBM Regatta series symmetric multiprocessor (SMP) servers, ruggedized for the shipboard environment, provide the low-latency computing throughput (rapid sensor-to-shooter loop closure) and high productivity software engineering environment.[3]

The AN/SPY-3 was originally to be combined with the S Band AN/SPY-4 under the designator "Dual Band Radar" on both the Zumwalt Class (DDG-1000) destroyer and Ford Class (CVN-78) aircraft carrier. On 2 June 2010, Pentagon acquisition chief Ashton Carter announced that they will be removing the SPY-4 S-band Volume Search Radar from the DDG 1000's dual-band radar to reduce costs as part of the Nunn-McCurdy certification process. Due to the SPY-4 removal, SPY-3 radar is to have software modifications so as to perform a volume search functionality. Shipboard operators will be able to optimize the SPY-3 MFR for either horizon search or volume search. While optimized for volume search, the horizon search capability is limited. Without the VSR, DDG-1000 is still expected to perform local area air defense. The Ford Class aircraft carriers will be the only platforms to have both radars married in one system.[4]


The system will be introduced in the new Zumwalt-class destroyers and Gerald R. Ford-class aircraft carriers. It is also under consideration for retrofit to existing ships (USS Makin Island (LHD-8), Nimitz-class aircraft carriers, and San Antonio-class amphibious transport docks. Other installation candidates are the LH(X) future ship class.[1]

See also


  1. ^ a b Pike, John. "AN/SPY-3 Multi-Function Radar (MFR)".
  2. ^ a b "Archived copy" (PDF). Archived from the original (PDF) on 2014-12-12. Retrieved 2014-10-28.CS1 maint: archived copy as title (link)
  3. ^ "Archived copy" (PDF). Archived from the original (PDF) on 2015-09-23. Retrieved 2014-11-03.CS1 maint: archived copy as title (link)
  4. ^