A dual-polarized antenna array comprising: a parallel plate polarizer, comprising: an upper plate having a first surface; a lower plate that is parallel to the upper plate and has a second surface opposing the first surface of the upper plate; a plurality of stepped septums extending from the first surface of the upper plate to the second surface of the lower plate, each of the plurality of stepped septums having a first side surface and a second side surface, the plurality of stepped septums comprising a first set of stepped septums and a second set of stepped septums that are inverted relative to the first set of stepped septums; a plurality of first divided waveguides associated with a first polarization, each of the plurality of first divided waveguides having a first set of opposing walls formed by a first portion of the first surface of the upper plate and a first portion of the second surface of the lower plate and a second set of opposing walls formed by a portion of the first side surface of one of the first set of stepped septums and a portion of the first side surface of one of the second set of stepped septums; and a plurality of second divided waveguides associated with a second polarization, each of the plurality of second divided waveguides having a first set of opposing walls formed by a second portion of the first surface of the upper plate and a second portion of the second surface of the lower plate and a second set of opposing walls formed by a portion of the second side surface of one of the first set of stepped septums and a portion of the second side surface of one of the second set of stepped septums. an upper plate having a first surface; a lower plate that is parallel to the upper plate and has a second surface opposing the first surface of the upper plate; a plurality of stepped septums extending from the first surface of the upper plate to the second surface of the lower plate, each of the plurality of stepped septums having a first side surface and a second side surface, the plurality of stepped septums comprising a first set of stepped septums and a second set of stepped septums that are inverted relative to the first set of stepped septums; a plurality of first divided waveguides associated with a first polarization, each of the plurality of first divided waveguides having a first set of opposing walls formed by a first portion of the first surface of the upper plate and a first portion of the second surface of the lower plate and a second set of opposing walls formed by a portion of the first side surface of one of the first set of stepped septums and a portion of the first side surface of one of the second set of stepped septums; and a plurality of second divided waveguides associated with a second polarization, each of the plurality of second divided waveguides having a first set of opposing walls formed by a second portion of the first surface of the upper plate and a second portion of the second surface of the lower plate and a second set of opposing walls formed by a portion of the second side surface of one of the first set of stepped septums and a portion of the second side surface of one of the second set of stepped septums.