Tri-band feed assembly systems and methods

A feed assembly for a reflector antenna comprising:

• a feed horn common to low, mid and high frequency bands;
• a coaxial polarizer to convert signals between circular and linear polarization in the low band frequency band and to support the mid and high frequency bands;
• a coaxial orthomode transducer (OMT) to separate two orthogonal signals and transition from coaxial waveguide to rectangular waveguides in the low band frequency band and to support the mid and high frequency bands;
• and
• a polyrod disposed in a center conductor of the feed assembly, wherein the polyrod is common to the mid and high frequency bands and supports the low frequency band;
• wherein respective 10-dB beamwidths for the low, mid and high frequency bands are approximately equal and wherein the respective 10-dB beamwidths are about 74 degrees.

A method comprising:

• receiving and transmitting signals using a feed assembly for a reflector antenna at low, mid and high frequency bands;
• providing a feed horn common to the low, mid and high frequency bands;
• receiving signals in the low frequency band using a coaxial polarizer and a coaxial orthomode transducer (OMT), wherein each of the coaxial polarizer and the coaxial OMT support the mid and high frequency bands;
• launching signals in the mid and high frequency band using a polyrod and a diplexer, wherein the polyrod and the diplexer support the low frequency band;
• and
• forming a portion of the coaxial polarizer further having a notched rectangular shape.