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News   Defense News

Long-Range Discrimination Radar Reshapes Adversaries' Calculus for Attacks Against U.S. Homeland

Dec. 7, 2021 | BY C. Todd Lopez , DOD News

The Missile Defense Agency, U.S. Northern Command and the Space Force marked the completion of construction on the long-range discrimination radar site at Clear Space Force Station, Alaska, during a ceremony on Monday.

The multi-mission LRDR is designed, for now, to better track incoming ballistic missiles. It combines the capabilities of lower frequency radars — which can track multiple objects in space at long range, but are not able to help warfighters determine which objects are a threat — with the capabilities of higher-frequency radars, which have a more limited field of view but are better able to "discriminate" among multiple objects and figure out what of those is dangerous.

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As ballistic missiles are launched and shed portions of themselves along their trajectory — including decoy and countermeasure material — the LRDR will help to determine which of those objects must be targeted by the missile defense system.

When fully operational, the multi-face LRDR — equipped with a 220 degree wide field of view and arrays measuring 60 feet high by 60 feet wide — will provide the ability to search, track and discriminate multiple, small objects in space, including all classes of ballistic missiles. Future iterations of the radar's software will allow it to also track hypersonic missiles.

The information the LRDR provides will increase the effectiveness of the missile defense system and help the U.S. Northern Command better defend the United States.

The capabilities the LRDR provides will also serve as a new kind of deterrent against potential missile attacks by adversaries, said Army Lt. Gen. A.C. Roper, the deputy commander of U.S. Northern Command.

"For years, the Department of Defense has subscribed to a mindset of deterrence through punishment — taking advantage of our global response to execute retaliatory strikes," Roper said.

A pyramid-shaped building.
Long Range Discrimination Radar
The Long Range Discrimination Radar at Clear Space Force Station, Alaska, is a multi-mission, multi-face radar designed to provide search, track and discrimination capability in support of U.S. homeland defense, Oct. 26, 2021.
Photo By: Missile Defense Agency
VIRIN: 211026-D-D0500-1001C

Secretary of Defense Lloyd J. Austin III has challenged the military to instead approach deterrence from a different perspective: deterrence through denial, Roper said.

"It's a defense designed to give our potential adversaries pause," he said. "It is the type of deterrence that shifts [their] cost-benefit calculus, providing doubt that an attack will be successful. And the LRDR helps to shift that calculus."

The general told those responsible for designing and building the new LRDR system that they have given potential adversaries something to think about if they're contemplating an attack on the U.S. homeland.

"This long-range discrimination radar is designed to defend the homeland by providing [the] unparalleled ability to search, track and discriminate multiple objects simultaneously," Roper said. "This radar provides a much-needed improvement to Northcom's homeland ballistic missile defense mission, ultimately resulting in more effective and efficient employment of the ground-based interceptors."

A photo of a military complex shows a large pyramid-shaped building.
Multi-Face Radar
The Long Range Discrimination Radar at Clear Space Force Station, Alaska, includes a multi-face radar designed to provide search, track and discrimination capability in support of U.S. homeland defense. The LRDR complex also includes a mission control facility, power plant and maintenance facility, Oct. 24, 2021.
Photo By: Ryan Keith, Missile Defense Agency
VIRIN: 211024-D-D0500-1001C

Full operational capability for the LRDR is expected in 2023, Navy Vice Adm. Jon A. Hill, director of the Missile Defense Agency said. Right now, the newly built LRDR will be evaluated and integrated into existing systems.

"This initial delivery is an important step to declare that we're done with a major construction. We are now fully into the test mode of this radar," Hill said. "That testing is so critical because it pushes you right into the integration, command and control into ground-based midcourse defense. That integration work will be complete and, then, in 2023, we'll be able to do operational acceptance for Northern Command."

Right now, the primary requirement met by the LRDR is against a ballistic missile threat, but in future iterations of the LRDR, tracking of hypersonic weapons can also be included without significant changes to the system, Hill said.

"That is what the radar filters are designed to go after," Hill said. "To bring in what I call a filter — which means you can then space your tracking and your timing to go to hypersonic — that's not a big leap ... that is a software upgrade, but it is not the driving requirement for LRDR today."