Wideband septum polarizer for reducing higher order mode

A septum polarizer comprising:

• a waveguide body;
• and
• a stepped septum disposed in a longitudinal direction inside the waveguide body and configured to divide the waveguide body into two parts, wherein:
• the septum polarizer comprises stepped portions of different heights to reduce a higher order mode in a preset frequency band,
• a first stepped portion is disposed on a front side of the waveguide body,
• a second stepped portion is disposed after the first stepped portion and configured to reduce a higher order mode,
• the second stepped portion includes at least one pair of steps,
• the pair of steps comprise at least two steps of different heights,
• among the at least two steps, a step with a higher height is disposed before a step with a lower height,
• the at least one pair of steps includes a first pair of steps disposed on a front side of the second stepped portion and a second pair of steps disposed after the first pair of steps, and
• an average height of the first pair of steps is lower than an average height of the second pair of steps.