Design of the Share-aperture Dual Circularly Polarization Waveguide Antenna Array

Due to remarkable advantages like high gain, low losses, simple feeding, easy manufacturing, precise control of aperture distribution, high power handling capability, robustness and reliability, slotted waveguide antenna arrays have been widely employed in radar and satellite communication (Satcom) applications. In this work, it is dedicated to develop a share-aperture dual circularly-polarized multilayer waveguide antenna array possessing advantages of low-profile, low AR, wide operating bandwidth and high-efficiency simultaneously. Planar horn array for radiation elements and a compact OMT are used to attain dual Linear-polarization. The antenna feed-network is configured using waveguide couplers to form circular polarization. A 40 x 20 elements planar array at K-band was designed with dimensions of 486 x 246 x 35 mm. The simulated results show that the VSWR is less than 1.5; the AR is less than 1.2 dB; the Gain is more than 36 dB; and the isolation between the two ports is more than 17 dB.