A Ka band planar slot array antenna for 45 degree linear polarization using substrate integrated waveguide

In this paper, a waveguide-fed series slot planar array antenna for 45° linear polarization (LP) operating in the Ka band is proposed. The inductive and capacitive loaded alternating reactance slot pairs are etched on the upper plate of radiating waveguides (WGs) as radiating units. Also all radiating slots are separated by a one-half guided wavelength and are fed by a standing-wave excitation. Grating lobes can be avoided in the direction of the guided wave propagation due to the dielectric materials of substrate and alternating reactance slot pairs. The antenna is designed using substrate integrated waveguides (SIWs) instead of dielectric-filled metallic WGs and verified using electrical performances such as reflection coefficient, gain, aperture efficiency, and radiation patterns using commercially available full-wave simulator, CST MWS.