Wideband Filtering Antenna Fed Through Hybrid Substrate Integrated Waveguide and Spoof Localized Surface Plasmon Structure

In this communication, we propose a novel feeding scheme to design a wideband filtering patch antenna. The antenna is composed of two substrates: the feeding and the radiating ones. Two circular patches are etched on the top surface of the radiating substrate as the radiators and a hybrid substrate integrated waveguide (SIW) and spoof localized surface plasmon (SLSP) structure is used as the feeding scheme. Due to abundant resonant modes and filtering feature of the hybrid SIW-SLSP structure, the antenna can radiate under the triple-mode resonance with high filtering performance. Moreover, the proposed filtering antenna has an independently adjustable capability of both low-band and high-band radiation nulls. The presented antenna is designed, fabricated, and measured. The measured results reveal that the operating bandwidth reaches up to 11.3%, ranging from 7.44 to 8.33 GHz. The peak gain of 10 dBi is obtained in passband with 10 dB gain suppression out of the band. This approach provides a simple way to design wideband filtering patch antenna, which can be easily integrated with planar circuit.