In this paper, performance of the double circular array antenna was analyzed, which has sharp directivity with specific direction and is compatible to shape pencil beam. The character of each array geometry which N numbers of isotropic point source is arranged in planar with type of a square, circular and double circular was compared and analyzed. As a result, we fined that double circular geometry was good performance rather than square and circular array geometry in the point of directivity. SLL and HPBW.