Investigation of Miniaturized Wideband Circular -polarized Cavity-Backed Printed Dipole Antenna

摘要

In this paper, a new crossed printed dipole antenna is proposed for the circular polarization, and the cavity technique is used to realize directional radiation and enhance the gain. The radiator consists of two vertical non-uniform butterfly-shaped dipoles, which are printed on the substrate of FR-4, and as well two parasitic strips vertical to the short dipole are added at the same layer to broaden the AR bandwidth. The dipoles are fed by the Balun where the contiguous monopoles of the two different dipoles are one pair as one of two feeding points. Moreover, the cavity is filled with the dielectric of FR-4 to greatly miniaturize the cavity dimension. Then the final overall size of the proposed antenna is 10mm*35mm*35mm (0.154λ_0*0.54λ_0*0.54λ_0) where λ_0 is the lowest working frequency.