John Hutchison & Ronnie Milione

The Philadelphia Experiment Recreated!

NAVY RADAR SYSTEMS

AN/SPS-49 Radar

The AN/SPS-49 radar is the navy's principal long-range two-dimensional air search radar. As such it has been used on a variety of combatants including aircraft carriers, Aegis and non-Aegis cruisers, destroyers, frigates, and amphibious ships including LSDs and LHDs. Up to 200 systems have been operational at one time. Originally developed to provide general air surveillance against aircraft, it also provides significant detection performance against both high altitude and sea-skimming missiles due to its high average power, clutter rejection, anti-jamming, and automatic detection features.

Several versions of the radar have been produced over the years including the following major variants:

• SPS-49(V)1 - Developed in the early 1970s. Included sidelobe cancellation and digital MTI. Video outputs provided to PPI displays.
• SPS-49(V)5 - Developed in the early 1980s. Added automatic detection and Doppler processing. Digital outputs provided to an associated tracker.
• SPS-49A(V)1 - Developed in the mid 1990s. Added radial speed determination on each target, each scan. Improved clutter rejection.

Major characteristics common to all versions of the radar include:

• FREQUENCY 850-942 MHz, three selectable 30MHz bands, 48 discrete frequencies
• PEAK and AVERAGE POWER 360 kW typical, 280 kW specified peak power; 12 kW average power
• ANTENNA
  • Parabolic Reflector: 8 ft X 24 ft, stabilized for roll and pitch
  • Gain: 28.5 dB
  • Beamwidths: 3.3� az, 11� elev, csc� to 20� elev
  • Rotation Rate: 12 or 6 rpm

The Radar Division of the Naval Research Laboratory has been involved in the SPS-49 program since its inception. Contributions include participating in specification development, design reviews, factory acceptance testing, and planning and conducting performance evaluation tests, both land-based and shipboard. A key feature of the most recent version of the radar, the SPS-49A(V)1 is single-scan radial velocity estimation of all targets allowing faster promotion to firm track and improved maneuver detection. This is done using unique signal processing techniques originated and tested by the Radar Division of NRL using 6.1 and 6.2 Office of Naval Research (ONR) funds. The results of this research have been transferred into production.

Specifications