Miniaturized SIW filter antenna with loadable sensor for various microwave sensing applications

In this paper, a novel substrate integrated waveguide (SIW) based filter antenna has been proposed for wireless sensor network applications. The proposed antenna consists of a fractal slot loaded miniaturized high-Q evanescent mode SIW bandpass filter section which provides a narrow pass band before the cut-off frequency of the unloaded SIW. A square patch monopole with partial ground plane, acting the radiating element, is cascaded to the filter. The sensor element can be integrated to the antenna on the slot area according to choice of applications. Depending on any measurable physical parameter, the dielectric constant of the sensor element changes and it affects the resonant frequency of the loaded filter antenna which can tune over a wide range. The antenna provides narrow band, high tuning range and easy integration to active circuits.