A full band waveguide orthomode transducer (OMT) includes first, second, and third waveguide sections coupled to one another, the first, second, and third waveguide sections respectively having a first port, a second port, and a third port. A first wire grid polarizer in the first waveguide section is transparent to electromagnetic signals having a first polarization and reflective of electromagnetic signals having a second polarization orthogonal to the first polarization. A second wire grid polarizer in the second waveguide section is transparent to electromagnetic signals having the second polarization and reflective of electromagnetic signals having the first polarization. The third waveguide section is configured to transmit and/or receive electromagnetic signals having the first polarization and/or the second polarization.