A Quadruple-polarized Reconfigu rable Antenna for 915 MHz ISM Band Applications

Abstract

In this paper, an ultra-high-frequency (UHF) quadruple-polarized reconfigurable antenna for 915MHz industrial, scientific, and medical (ISM) band applications is proposed. The proposed antenna consists of a disk-shaped radiator, four port feeding network which integrates microstrip lines and a 90 degrees hybrid coupler, and a SP4T RF switch for polarization control. By switching the operating modes on the feeding network, the quadruple-polarized reconfigurable antenna with LHCP, RHCP, VLP, and HLP can be obtained. Using a FR4 substrate, the proposed antenna was designed and implemented. The peak gain and antenna size at 915MHz of the proposed antenna are approximately 6.4 dBi(c) and 0.53 lambda Z(0) (D) x 0.08 lambda Z(0), respectively.