For two coupled long josephson junctions , we calculate the maximal emitted power which exceeded prediction value of the superradiation theory largely . our investigations displayed that it is chaos to lead the radiation to the maximal value 对于两个耦合的长josephson结,我们的研究表明,混沌使结的辐射功率趋于极大值,并进而算出了最大的辐射功率,它远远超出了超辐射理论的预言值。