A Triband Shunt-Fed Omnidirectional Planar Dipole Array

A novel shunt-fed triband printed two-element collinear dipole array is presented in this letter. The planar dipole array configuration is designed using two shunt-fed back-to-back dipole elements with omnidirectional pattern. The motivation for this work was to devise a novel feed structure that has an advantage of structural simplicity with good performance. The proposed antenna can provide the required bands of GSM850 (824-894 MHz), DCS (1710-1880 MHz), and PCS (1850-1990 MHz) with S
₁₁
<; -10  dB. A prototype array antenna is fabricated and measured. Good omnidirectional radiation with gain variations less than 1.5 dBi in the azimuth plane has been obtained. Enhanced antenna gain about 3.4 3.8 dBi for GSM850 band and about 3.85.5 dBi for DCS/PCS bands are achieved. It is significant that the designed triband dipole array maintained good radiation efficiency values at all bands.