Planar Excitation of Dielectric Waveguide Antenna for Broadband and High-Gain Application

In this letter, a linearly tapered dielectric waveguide antenna with planar substrate integrated waveguide (SIW) feeding is presented for Ku-band (12-18 GHz) application. To make the feeding network planar, the SIW and central part of antenna are fabricated on a single substrate. Two metal strips are mounted on each top and bottom side of the central part of the antenna element for matching purpose. The antenna is designed and optimized using Ansoft HFSS. The optimized prototype is fabricated and measured. An endfire radiation pattern is achieved with low sidelobe (around 12 dB) and cross-polarization (around 20 dB) level in both E- and H-planes. The measured impedance bandwidth and maximum gain are 33.3% (11.5-16.1 GHz) and 12.4 dBi, respectively.