Study of a planar magnetic-electric dipole antenna

A planar complementary magnetic-electric dipole antenna structure is proposed. The proposed antenna is composed of a folded dipole antenna and a periodical capacitive loaded loop antenna. The current along the periodical capacitive loaded loop is uniform in amplitude and phase, therefore, the loop antenna is equivalent to a magnetic dipole, the radiation pattern of which is complementary to that of the folded dipole antenna. According to Huygens´ theory, the complementary antenna could achieve a unidirectional radiation pattern. The simulations reveal that, in about 400MHz operating frequencies, more than 10dB front-to-back ratio and identical radiation patterns in the E-plane and the H-plane of the proposed antenna could be obtained, a desirable gain performance can be achieved as well.