The U.S. has agreed to sell Japan a long range anti-missile radar, which will be placed in southern Japan to watch for North Korean ballistic missile attacks. This AN/TPY-2 radar is an X-Band phased array system similar to those used in the SBX (Sea Based X Band radar). The AN/TPY-2 is used with the THAAD anti-missile system as well.
Japan has three Aegis equipped destroyers that can fire anti-missile missiles. Last year the United States towed its SBX to Japan in anticipation of a North Korean long-range ballistic missile launch . SBX is a large long range radar built on a floating platform that can be towed to wherever it is needed. The X-Band radar can see over the horizon and gives anti-missile systems that maximum warning time that a target is on the way.
The North Korean rocket failed shortly after launch, falling into the sea off the coast of South Korea. The North Korean rocket failed before the Japanese had a chance to fire any of their anti-missile missiles. The North Koreans are preparing another long range ballistic missile for launch and the Japanese are ready to shoot it down as well. The Japanese are also concerned with a possible missile threat from China because of disputes over who owns some uninhabited islands.