Ku-band Dual-polarized Antenna Research

With the rapid development of electronic communication, especially in satellite communications, Ku band dual polarized antenna research become very necessary. Waveguide slot antenna has been widely used in missiles, aircraft and other aircraft under high-speed operation, its show good superiority, also apply in the satellite communications.This paper discusses the radiation mechanism of rectangular waveguide slot, waveguide slot of various types and corresponding forms of theoretical analysis method.Analyses the structure characteristics of the waveguide array and Taylor diameter distribution theory, and write a MATLAB program to calculate Taylor distribution wire source excitation current value.Designed a±45°double polarization waveguide slot antenna. Changed waveguide aperture polarization direction by cavity structure, and radiating element structure is designed. Coupling gap is used "zhi" structure to slove the center feed of the ridge waveguide.Detailed theoretical derivation is presented of the extraction of active admittance of radiating slot and active impedance of coupled slot, and through the simulation calculation, finally it is concluded that the active admittance and active impedance calculation formula, simplify the design process. Designed the standing-wave linear array and realized the aperture control of linear array units,8units linear array gain is achieved15.35dB, Sidelobe level to meet the requirements of-20db. Design the8*8units of dual polarized antenna, antenna overall size is about160mm*160mm*14mm, gain of22.5dB, and use Taylor diameter distribution reduces the antenna sidelobe level of E-plane and H-plane, realize the design requirements.In order to reduce the volume of the dual polarized antenna and avoid using the cavity structure, designed a waveguide slot antenna feed with double polarization feed. Focuses on the design of the double polarization feed,the double polarization feed is of superior performance. Coupled waveguide uses square waveguide instead of rectangular waveguide, based on the characteristics of square waveguide surface current distribution, analyzed the different coupling aperture.