Reduction of Cross Polarization of Slotted Microstrip Antenna Array Using Spiral‐Ring Resonator

Abstract

ABSTRACTDesign of a (2 × 2) E‐shaped microstrip patch antenna array integrated with spiral‐ring resonators (SRRs) is introduced for the reduction of cross‐polar (XP) radiation. The addition of SRRs in the array structure does not affect other characteristics of the array antenna. The array is designed to function in the 5.25 GHz that corresponds to IEEE 802.11a wireless LAN application. The characteristic analysis such as return loss (RL), bandwidth (BW), and radiation patterns of the antenna with and without SRRs have been investigated. The array offers a BW of 405 MHz (for RL < −10 dB) covering frequencies ranges from 5.175 to 5.580 GHz and gain of 12.84 dBi has been achieved. The array has been studied both numerically and experimentally by introducing SRRs. The SRR geometry has been optimized for minimum XP radiation. The XP radiation has been reduced by 7 dB with two SSRs and 12.0 dB by four SRRs of similar geometry, placed in between the patch elements of the array structure. Prototype antennas with and without SRRs have been fabricated tested and a remarkable agreement is obtained between the measured and the simulated results. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2083–2088, 2013