摘要 |
A dual band multimode coaxial antenna feed has an inner section of longitudinal hollow waveguide having first and second orthogonal mode transducers that interface first and second orthogonally polarized cylindric al waveguide TE11 mode signals lying in a first upper (e.g.,Ka) frequency band. An outer coaxial waveguide section has a Potter horn surrounding the inner waveguide section, which terminates at a polyrod. The outer section includes third and fourth orthogonal mode transducers that interface orthogonally polarized coaxial waveguide TE11 mode signals lying in a second lower (e.g., X) frequency band. A tracking port coupled to the outer coaxial waveguide secti on provides an output representative of the difference pattern of the radiation profile produced by transverse electromagnetic TEM mode signals generated an d propagating in the outer coaxial waveguide. A mode supressor in the outer waveguide section adjacent its two orthogonal mode transducers locally supresses TEM signals in their vicinity.
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