A high-gain and low cross-polarized wave-fractal shaped printed antenna for DBS application

Abstract

This article presents the design of a printed antenna for Direct Broadcast Satellite (DBS) (12.2 – 12.7 GHz) services. The newly designed proposed structure, named as ‘wave-fractal’, is having a considerably high gain and can heavily suppress cross-polarization level along the entire HPBW region. The radiating area of one-quadrant of structure is derived by superimposing six numbers of ‘Golden-ratio’ based squares, and it poses 2D-quadrantal symmetry. In order to resonate the structure at desired frequency, two parallel slots and a circle based defective ground structure is imposed. Furthermore, to achieve a symmetric radiation pattern, a 2D-Octagonal symmetry has been implemented on the proposed structure. The fabricated prototype resonates at 12.49 GHz and gives a gain and x-pol. as 9.52 dBi and −35.36 dB, respectively. The measured impedance bandwidth is 502 MHz, which ensures 100% bandwidth coverage for the DBS band. The measured results make an excellent agreement with its simulated counterpart.