Reconfigurable Wide Band Circularly Polarized Antenna Array for WiMAX, C-Band,a and ITU-R Applications with Enhanced Sequentially Rotated Feed Network

摘要

In this article, a wide-band circularly polarized slot antenna array with reconfigurablernfeed-network for WiMAX, C-Band, and ITU-R applications is proposed. Differentrnnovel methods are used in proposed array to improve antenna features such as impedancernmatching, 3 dB axial-ratio bandwidth (ARBW), gain, and destructive coupling effects. Miniaturizedrndual-feed square slot antenna, with one attached L-shaped strip and a pair of Tshapedrnstrip at ground surface for improving impedance matching and circular polarizationrn(CP) purity, is presented. For further enhancement of CP attributes, reconfigurable sequentiallyrnrotated feed network is utilized to obtain wider 3 dB ARBW. Furthermore reconfigurablernproperty of network gives controlling Right and Left handed CPs, respectively. Finally,rna special form of Electromagnetic Band gap structure is employed on top layer of substraternthat provides high isolation between radiating elements and array feed network to enhancernoverall performance of antenna. The measured results depict 3 dB ARBW from 4.6 torn7.2 GHz, impedance bandwidth from 3.3 to 8.8 GHz for VWSR<2, and peak gain of 10 dBirnat 6 GHz.