WASHINGTON — Raytheon will participate in a missile defense radar “sense-off” to test designs that could be included in the U.S. Army’s Integrated Air and Missile Defense system under development.

The Army announced plans for the sense-off in October, resetting the approach for the Lower Tier Air and Missile Defense Sensor, or LTAMDS, program that has struggled to bring about a new radar for well over a decade.

The sense-off is “separate and distinct” from contracts awarded to Raytheon and Lockheed Martin last fall to come up with design concepts for a new missile defense radar, according to Bob Kelly, Raytheon’s director for integrated air and missile defense in the company’s Integrated Defense Systems division, who spoke with reporters Thursday.

According to an Oct. 29 notice posted to the Federal Business Opportunities website, the sense-off will take place this spring at White Sands Missile Range, New Mexico. Each vendor with a radar will have roughly two weeks on the range to demonstrate capabilities. A down-select will happen by the end of the year.

“We can meet the timeline for both the sense off and initial operational capability in fiscal year 2022,” Kelly said.

However, it’s unclear what this means for the prior technology development program. Kelly said that effort remains relevant, with the contract ongoing, but referred any further questions about its status to the Army.

“Our developmental efforts — what we do for one, it serves the other as well,” he said. “We were both [Raytheon and Lockheed Martin] going to develop prototypes. But with the sense-off, we’re doing it faster,” and with more competitors.

The sense-off strategy accelerates the timeline by a couple of years, Kelly said.

The other lingering question is whether the LTAMDS will include 360-degree coverage — a high priority for the Army, but seemingly one downsized in importance for the LTAMDS effort.

“The threshold is not for a 360-degree radar,” Kelly said, adding that Raytheon’s base design does include the capability. “We have a lot of scalability in our system, so if the Army decides they don’t want [360-degree coverage], we can give them the opportunity in the future to upgrade.”

The Raytheon-made Patriot air and missile defense radar was first fielded in the 1980s, and the Army attempted to replace the system with Lockheed Martin’s Medium Extended Air Defense System through a co-development effort with Germany and Italy. But that program was canceled in the U.S. after closing out a proof-of-concept phase roughly six years ago.

Since then, the Army has studied and debated how to replace the Patriot radar with one that has 360-degree detection capability, while Raytheon continues to upgrade its radar to keep pace with current threats. It is acknowledged that there will come a point where that radar will not be able to go up against future threats.

“The Patriot remains exceptional” today, Kelly said. “LTAMDS is looking out beyond tomorrow.”