A missile defense advocacy group wants the Pentagon to deploy from Pearl Harbor the anti-ballistic missile tracking system known as Sea-Based X-Band Radar to monitor the planned North Korean rocket launch.

However, there has been no official word on what the Pentagon plans to do.

The Pearl Harbor-based destroyer USS Chafee, armed with the sophisticated Aegis radar and missile weapon systems, has been ordered to be part of the flotilla of warships that will monitor the North Korean launch planned between Saturday and April 11. The Chafee initially was in South Korea with six other U.S. warships as part of 12-day joint defense exercises in early March.

The Aegis combat system can simultaneously detect, track and destroy a multitude of targets. But the X-Band radar platform has more powerful sensors, capable of discriminating rocket stages and payload, including a possible dummy warhead.

North Korea has said it intends to launch a satellite, but a 2006 U.N. Security Council resolution bars the rogue state from experimenting with space-launch technology.

Defense Secretary Robert Gates has said there are no plans to shoot it down.

“;I think if we had an aberrant missile, one that was headed for Hawaii, that looked like it was headed for Hawaii or something like that, we might consider it,”; Gates said this week on “;Fox News Sunday.”;

Two weeks ago, Adm. Timothy Keating, commander of U.S. forces in the Pacific, said in an interview with ABC News that the U.S. military was “;fully prepared”; to shoot down the missile if ordered to do so.

In a letter to Gates earlier this week, Riki Ellison, chairman of the Missile Defense Advocacy Alliance, urged the Pentagon to “;consider activating all available missile defense assets to the Pacific to protect against an errant space launch attempt or a ballistic missile launch that threatens the United States or our allies.”;

On its Web site, the nonprofit alliance, which supports a missile defense shield for the U.S., noted that an ideal orbital launch from North Korea, using optimal rotation of the Earth, would take the booster over Japan and east over the Pacific.

The group noted that the $950 million SBX, perched on a semi-submersible oil rig, is “;the most powerful and most capable sensor”; to track the launch.

“;If deployed, the SBX can begin to emit its sensor 50 or so miles from Hawaii and can become effective by providing sensoring information to the deployed long-range missile defense system in place today,”; the group said.

The rig was diverted from tests in 2006 to track a North Korean Taepodong-2 that failed shortly after launch.

The 280-foot radar platform has been a frequent visitor to Pearl Harbor, arriving in February for maintenance work.