A Compact design of antenna feed for 6 M S/X-bands mono-pulse auto-tracking ground station

A compact S-band auto-tracking antenna feed for 6 m mono-pulse auto-tracking ground station is presented. It is designed to reduce the effect of blockage of the antenna systems and modify the orientation angle of the main reflector to align antenna boresight with a satellite. A circular waveguide is designed to connect to the septum polarizer for communication between the earth and LEO satellite. Based on the circular waveguide as an inner metal, a cylindrical metal is added as an outer metal to form a coaxial line for tracking LEO satellite. The uplink band of the antenna feed is from 2.025 to 2.12 GHz and the downlink band is from 2.2 to 2.3 GHz. The results show that the antenna gain of 6 m reflector is about 39.7 dBic and the 1-dB-beamwidth is 1 degree. The polarization isolation between sum and difference patterns is larger than 30 dB, and the axial ratio is lower than 1.1 dB within ± 0.5 degree range.