MILLIMETER-WAVE RECTANGULAR METAL RIDGE WAVEGUIDE SLOTTED ANTENNA ARRAY

Abstract

In radar and communications applications, waveguide slot arrays are commonly employed, particularly when it is imperative to have smaller dimensions, higher power handling capacity, and high gain. Applications for radar require emission patterns with narrow beam and precise low sidelobe levels for tracking and detection, whereas highly customized shaped main beams are essential for other applications. This research describes 1D linear (1×16) and 2D planar array (8×16) an original design for the Ka band waveguide slot antenna. The aperture size is decreased by using ridge inside the waveguide. Three distinct classifications applied for this work in ridge waveguide’s feed are: end feed single ridge waveguide, right angled bend feed single ridge waveguide, and aperure coupled slot center feed single ridge waveguide. The Simulated aperture coupled slot center feed single ridge waveguide 1D linear antenna design results in a 3D radiation pattern. Far field realized gain achieved in this design are 16.94 dBi gain, and far field directivity is 17.47 dBi at 30 GHz center frequency.Radiation efficiency simulated at 95 % efficiency through frequency solver,and simulated input coefficient for reflection is greater than -20 dB over a 246 MHz bandwidth. HPBW in E-plane is 68.4◦ and 6◦ in H-plane. Scope of the work also extended to the 2D planar array slotted waveguide antenna design to increase the antenna gain and directivity. It assembles a Ka-band (26.5 GHz to 40 GHz) antenna. WR28 standard rectangular metal waveguide used as feeding waveguide and single ridge rectangular waveguide used for radiating waveguide. Corporate feeding mechanism used for wide bandwidth. Waveguide antenna array has been designed with a (8×16) slots in a broadwall section. Far field realized gain simulated with this antenna array of 24.85 dBi in the broadside direction. Radiation efficiency simulated at 90 % efficiency through frequency solver,and simulated input coefficient for reflection is greater than -10 dB over a 140 MHz bandwidth. The radiation diagram that was produced after the design models were run with CST Microwave Studio. The requirements for the design were satisfactorily addressed.