A double-frequency antenna structure with a high degree of electrical isolation between long distance and short distance antennas includes a dielectric substrate having at least two corners and a center area. A first set of antenna arrays is positioned at the corners. A second set of antenna arrays is positioned at the center area. At least one first folded isolation plate is mounted on the dielectric substrate, and positioned between the first set of antenna arrays and the second set of antenna arrays. At least one second folded isolation plate each is mounted on one first folded isolation plate.