Substrate integrate waveguide quasi Yagi antenna using SIW-to-CPS transition for low mutual coupling

In this paper, the substrate integrated waveguide (SIW) quasi-Yagi antenna is proposed to enhance the low mutual coupling characteristics by using the SlW-to-CPS transition. The proposed design is based on impedance and mode matching method between the antenna components, such as quasi-Yagi antenna, the CPS feed, and the SlW-to-CPS transition. Moreover, the mutual coupling between neighboring elements of a quasi-Yagi antenna array is lower than the microstrip quasi-Yagi antenna with a measured level of <; 29 dB for a 2element structure with λ0/2 (where λ₀ is a free-space wavelength at the center frequency of 9.5 GHz) separation. The phased array system using the proposed work can be applied with low mutual coupling characteristics can be applied to various applications in modern communications and radar systems as well as millimeter wave imaging arrays.