摘要 |
A multi-channel feed network includes a main waveguide section (either square or circular) for connection to a satellite antenna for propagating two orthogonal polarizations. The feed network further includes a low pass section connected on axis with the main waveguide, the low pass section having the same cross section as the main waveguide, and a high pass section also connected perpendicular to the main waveguide. The low pass section includes a band reject filter (BRF) formed from slots cut to reject higher frequency signals. The high pass section can be a rectangular waveguide which functions to filter low frequency signals. The feed network can be configured to support a number of different polarizations. Orthogonal linear polarizations are provided for the high frequency bands by adding additional high pass sections connected by power dividers, and for the low frequency bands by adding a conventional OMT. Adding a polarizer between the antenna and main waveguide section enables both the high pass and low pass sections to support left or right hand circular polarization. By adding a 90° degree hybrid coupler, the high pass section can support circular polarization alone. By adding a polarizer and OMT after the low pass section, the low pass section can support circular polarization alone. By using two 90° degree hybrid couplers and two power dividers, a network can be created to support dual circular or linear polarizations.
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