Raytheon’s nine-story-high X-band Radar (XBR) is the world's largest X-band radar.

The sea-based X-band (SBX) platform that it sits on stands more than 250 feet high and displaces more than 50,000 tons. It consists of a semi-submersible oil production platform topped with the XBR.

XBR is the primary payload on the semi-submersible platform supporting the Ground-Based Midcourse Defense phase of the Missile Defense Agency Ballistic Missile Defense System.

SBX's floating platform, a modified oil-drilling vessel, was designed for exceptional stability in high winds and storms. Measuring 240 feet wide and 390 feet long, the vessel includes a power plant, bridge and control rooms, living quarters, storage areas, and enough floor space and infrastructure to support the X-band Radar.

The X-band Radar itself, which sits on top of the floating platform, is the largest, most sophisticated phased array, electro-mechanically steered X-band radar in the world.

It consists of thousands of elements driven by transmit/receive (T/R) modules. In the X-band Radar, they provide the full fire control sensor functions for the Ground-Based Midcourse Defense system, including search, acquisition, tracking, discrimination and kill assessment.

The SBX component was developed under the direction of the Boeing Company.