Design and Analysis of a Coupling-Fed Printed Dipole Array Antenna With High Gain and Omnidirectivity

Abstract

A printed omnidirectional dipole array antenna with a radiated load is proposed and analyzed, which is fed by a coplanar waveguide. Flying lines and via-holes are used to connect dipoles to achieve a balanced feed. Simulated results by CST microwave studio® indicate that the operating band is 4.6 to 4.9 GHz with its reflection coefficient less than -10 dB. The omnidirectional gain in this band is higher than 4.23 dB and the antenna size is only 103.4mm × 12.6mm × 1.5mm. As a result, its gain per wavelength can reach a high value of 3.1 dB/λ at 4.7 GHz, which is conducive to antenna miniaturization and batch production. In order to effectively decrease the outer surface current on the coaxial feeder outer conductor, a printed choke is introduced, so that the antenna performance would not be affected by an even longer coaxial line. The bandwidth and gain are improved achieving 4.63-5.45GHz and 5.8dB, respectively. There is a broad application of the designed antenna for it not only can be used independently, but also can be integrated on the printed circuit board.

Keywords

• Printed antenna
• radiated load
• antenna miniaturization
• printed choke
• fed by coplanar waveguide