Antenna design studies for a U.S. domestic satellite

This paper describes antenna design studies for application to U.S. domestic communications satellite systems using orthogonal linear polarization to achieve frequency reuse. Antennas with polarization-selective reflection or transmission surfaces can achieve the highest beam polarization isolations (35-50 dB), but have the greatest mechanical design complexity. Antennas with dual-polarized feed systems generate orthogonally polarized coincident beams from a single reflector in mechanically simple configurations. Worst-case polarization isolations achieved over the coverage region(s) range from 30-35 dB. The necessity of swept frequency measurement techniques to completely and accurately characterize the polarization isolation, gain, and frequency-sensitive beam squint of the antenna system is demonstrated.