The U.S. Missile Defense Agency has examined 46 sites in Hawaii for a sophisticated missile discrimination radar that would better defend the state against North Korea as well as future hypersonic weapon threats from China and Russia, officials said.

A specific site for the radar has not been chosen, according to the agency. An environmental impact statement is needed first, and public outreach meetings are anticipated in late June, the agency said.

Inside Defense reported that the Homeland Defense Radar-Hawaii would cost $763 million. It is expected to become operational in 2023.

The Pentagon also is seeking another sensor for the Pacific at an as-yet unidentified location.

“Both radars will close coverage gaps in the Pacific architecture and provide persistent long-range acquisition and midcourse discrimination, precision tracking and hit assessment” against long-range missile threats, Lt. Gen. Samuel Greaves, director of the Missile Defense Agency, told a congressional committee last month.

“Discrimination” refers to the ability to distinguish actual warheads from rocket debris, countermeasures and decoys.

The agency said it had looked at 46 sites in Hawaii on Defense Department land, adding that it “plans to examine potential site locations as part of the environmental impact statement process.”

A third ground sensor, the Long Range Discrimination Radar, is being built at Clear Air Force Station in Alaska with initial operation expected in 2020.

The Pentagon wants the increased sensors for North Korean ballistic missiles. But it is also concerned about the coming wave of hypersonic weapons from China and Russia.

Hypersonic missiles can be fired from intercontinental ballistic missiles or released from a bomber similar to a cruise missile and are maneuverable, taking away the predictability of an ICBM’s arc, according to the Missile Defense Advocacy Alliance.

“Hypersonic weapons travel along the edge of space and accelerate to between Mach 5 (around 3,800 mph) and Mach 10 (over 7,500 mph),” the nonprofit group said.

The threat of hypersonics “is real and coming,” Greaves said last month.

The Missile Defense Agency wants space-based sensors and the improved ground-based radars, including in Hawaii, to be able to feed better data to missile interceptors. Forty-four defensive interceptors are in Alaska and California. The agency wants to expand that to 64 in by around 2023.

Riki Ellison, chairman of the advocacy alliance, said the Hawaii and Pacific radars should be capable of scanning multiple directions because hypersonic missile threats can originate from multiple locations.