3 February 2016 www.navy.mil
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.
The radar consists of four air cooled below deck cabinets, a motor generator and one above deck Antenna unit. The antenna is designed, constructed and tested for low radar cross-section reflectivity (or signature) as required for stealth ship design and meets all MIL-STD-901D shock requirements. The AN/SPQ 9B radar is an unattended system. Preventative maintenance is scheduled for 3.5 hours per week.
The radar has 90dB of clutter rejection in the air channel and 70dB of clutter rejection in the surface channel. This provides superior sub-clutter visibility.
Above decks, the radar uses a mechanically rotating, electronically stabilized antenna. The lightweight (1,500 lbs.) antenna consists of dual planar arrays mounted back-to-back, each connected to independent transmitters and receivers.