Dual-band dipole antenna with dual flat reflectors

A dipole antenna with a flat reflector can achieve unidirectional radiation pattern with a simple structure. However, the distance between a reflector and an dipole element is required 1/4 wavelength. In order to use in two or more frequency bands, it is necessary to use individual dipole element for each frequency band. This paper proposes a dipole antenna with dual flat reflectors. In addition, effect of the reflector structure on the beamwidth in dual frequency bands is clarified. Moreover, the effects of parasitic elements arranged close to the dipole element on the band characteristic of the VSWR is considered. Furthermore, it is shown that an impedance matching is realized in dual bands.