Sensor-Integrated Aperture Coupled Patch Antenna

Abstract

The aim of this work is to develop a gas sensor integrated into a 2.4 GHz patch antenna. The detection mechanism is to track the resonant behavior of an antenna coupled to an interdigitated capacitor (IDC) on which a sensing material is deposited. When the target gas is adsorbed on the material surface, the effective permittivity changes and a variation in the antenna resonant frequency is observed. In order to avoid compromising either the antenna performance or the sensor performance after deposition of the sensing material, the coupling between the patch radiator and the IDC should be weak. For this reason, an aperture coupled patch (ACP) antenna weakly coupled to an IDC is employed. In this paper, the authors describe the ACP antenna design and its integration with an IDC, its fabrication and testing.