Reconfigurable microstrip patch antenna with switchable polarization

Abstract

A novel reconfigurable microstrip patch antenna with frequency and polarization diversities is proposed. A U-slot is incorporated into a square patch, and a PIN diode is utilized to switch the slot on and off, which realizes the frequency diversity characteristic. The polarization diversities among linear polarization (LP), right-hand circular polarization (RHCP), and left-hand circular polarization (LHCP) are also obtained by switching three PIN diodes on the slot and the truncating corners of a square patch on and off. The antenna design and experimental results are presented. The reconfigurable microstrip antenna in (6) was capable of making polarization diversity among LP, RHCP, and LHCP. In this letter, we propose a novel reconfigurable microstrip patch antenna having frequency and polarization diversities simultaneously. A U-slot is incorporated into the square patch. The frequency diversity characteristic of the antenna is realized by switching a PIN diode on a U-slot of a microstrip patch on and off. The polarization diversity is also obtained by turning three PIN diodes on the slot and the truncating corners of a square patch on and off. The proposed antenna is designed to operate at 2415 MHz in wireless local area network (WLAN) systems or at 2650 MHz in digital multimedia broadcasting (DMB) systems. The design has been successfully implemented and the experimental results are presented.