Substrate integrated waveguide cavity backed mushroom antenna with broadband and high gain

This paper proposes a substrate integrated waveguide (SIW) cavity backed mushroom antenna with broadband and high gain. The proposed antenna with size 40mmx50mm consists of a 2 x 2 array mushroom unit cells, microstrip feeding line and a SIW back cavity. The following factors produce broadband: (1) Mushroom antenna is capable of exciting multiple resonances in a N-cell mushroom resonator. (2) The reduced quality factor due to mushroom antenna substrate. The following factors produce high gain: (1) The existence of the mushroom radiating gaps. (2) The SIW back cavity further improves antenna gain. The simulated bandwidth, peak gain are 70% (from 4.9GHz to 8.5GHz) and 9.9dBi, respectively. Compared with reference, the size is reduced by 44% and the bandwidth is increased by 40%