Aperture-coupled UHF RFID reader antenna for a handheld application

Abstract

This article presents a new UHF RFID reader antenna for a handheld reader system. An aperture-coupled structure is employed to cover the North American UHF RFID frequency band: 902928 MHz. A thick high-dielectric substrate with a relative permittivity of epsilon(r) = 8 is used for the size reduction. The rectangular stubs on the proposed annular ring patch contribute to effective impedance matching and good axial ratio performance. The proposed antenna has a total volume of 100 mm X 100 mm X 9.6 mm and exhibits a maximum RHCP gain of 2.68 dBi and an average axial ratio of 1. 1 dB for the application frequency band.