Long Range Discrimination Radar

The Long Range Discrimination Radar (LRDR) that is planned for operational service in Alaska in 2020 is part of the United States's Ground-Based Midcourse Defense anti-ballistic missile system. The main contractor is Lockheed Martin, under a US$784 million contract from the Missile Defense Agency in October 2015.

LRDR is a gallium nitride (GaN)-based, solid-state active electronically scanned array (AESA) early-warning radar that allows for continuous coverage, even when it is undergoing maintenance. The radar consists of individual solid state radar blocks that can be combined to scale up the size of the radar. The multi-purpose GaN device used on the prototype version of the LRDR is from the Japanese electronics company Fujitsu, according to Lockheed Martin.

Construction in Alaska for the LRDR was scheduled to begin in 2019, tentatively at Clear Space Force Station in central Alaska. Each AESA's dimensions are 60 feet high by 60 feet wide; the field of view is 220 degrees.

In late February 2021, the Missile Defense Agency said that the radar installation was underway, with Initial Operational Capability to be achieved in 2021. Testing for Full Operational Capability is expected by 2023.

In mid-August 2023, the Flight Test Other-26 (FTX-26) was cancelled due to an anomaly with the live ballistic missile target. When operation, the LRDR will be tied into the Ground-Based Midcourse Defense system and the Command and Control, Battle Management and Communications system.