A dual-band unidirectional coplanar antenna for 2.4–5-GHz wireless applications

A dual-band unidirectional antenna has been developed. The dual-band antenna consists of a long dipole for the lower frequency band and two short dipoles for the higher frequency band. All dipoles are printed coplanar on a thin substrate. The printed dipole antenna is excited by a microstrip line. The higher-order mode in the higher frequency band has been suppressed, leading to a good unidirectional pattern in the both frequency bands. This dual-band unidirectional antenna may find application in base stations and/or access points for 2.4/5- GHz wireless communications.