The AN/TPY-2 radars are high resolution, phased array, X-band radars designed and built specifically for the missile defense mission. The radar can be deployed in one of two modes: terminal or forward-based.: In terminal mode, the TPY-2 radar is integrated with a THAAD system, and serves as its primary sensor. In this mode, the sensor is oriented upward to track the late stages of the missile track enabling the THAAD's capability to intercept both outside the atmosphere and once a reentry vehicle enters the atmosphere. This mode carries a shorter range because of the orientation of the radar.

In forward-based mode, the radar provides crucial sensor tracks of missiles in boost/early midcourse phase to the GMD system. From these forward-based locations, the TPY-2 are able detect and track missiles in their boost and early midcourse phases, determining information such as its speed and trajectory.