A circulator (100, 500, 800, 1000) comprising: a waveguide housing (102, 502, 802, 1002) having a plurality of hollow waveguide arms (122, 522, 822, 1022) that communicate with a central cavity (120, 520, 820, 1020), wherein the waveguide arms include, and the central cavity is defined by, a floor (108, 508, 808, 1008), a ceiling (110, 510, 810, 1010), and a plurality of sidewalls (112, 512, 812, 1012) connected between the floor and the ceiling, wherein at least one of the floor or the ceiling includes at least one step (116, 516, 816, 1016) which defines a junction between a first region having a first height (114, 514, 814, 1014) between the floor and the ceiling and one or more second regions having a second height (115, 515, 815, 1015) between the floor and the ceiling, the first region proximate the central cavity (120, 520, 820, 1020) and the one or more second regions proximate the waveguide arms (122, 522, 822, 1022), wherein the first height is larger than the second height; a ferrite element (104, 504, 804, 1004) disposed in the central cavity (120, 520, 820, 1020) of the waveguide housing (102, 502, 802, 1002), the ferrite element including a plurality of arms (118, 518, 818, 1018) corresponding to the plurality of hollow waveguide arms (122, 522, 822, 1022); and one or more quarter-wave transformers (106, 506, 806, 1006) attached to the ferrite element (104, 504, 804, 1004), each quarter-wave transformer protruding from a respective arm (118, 518, 818, 1018) of the ferrite element into a respective waveguide arm (122, 522, 822, 1022), the one or more quarter-wave transformers proximate the at least one step (116, 516, 816, 1016); characterized in that: each quarter-wave transformer is a quarter-wave dielectric transformer; each quarter-wave dielectric transformer is respectively attached to a distal end of each arm of the ferrite element and protrudes into a respective waveguide arm. a waveguide housing (102, 502, 802, 1002) having a plurality of hollow waveguide arms (122, 522, 822, 1022) that communicate with a central cavity (120, 520, 820, 1020), wherein the waveguide arms include, and the central cavity is defined by, a floor (108, 508, 808, 1008), a ceiling (110, 510, 810, 1010), and a plurality of sidewalls (112, 512, 812, 1012) connected between the floor and the ceiling, wherein at least one of the floor or the ceiling includes at least one step (116, 516, 816, 1016) which defines a junction between a first region having a first height (114, 514, 814, 1014) between the floor and the ceiling and one or more second regions having a second height (115, 515, 815, 1015) between the floor and the ceiling, the first region proximate the central cavity (120, 520, 820, 1020) and the one or more second regions proximate the waveguide arms (122, 522, 822, 1022), wherein the first height is larger than the second height; a ferrite element (104, 504, 804, 1004) disposed in the central cavity (120, 520, 820, 1020) of the waveguide housing (102, 502, 802, 1002), the ferrite element including a plurality of arms (118, 518, 818, 1018) corresponding to the plurality of hollow waveguide arms (122, 522, 822, 1022); and one or more quarter-wave transformers (106, 506, 806, 1006) attached to the ferrite element (104, 504, 804, 1004), each quarter-wave transformer protruding from a respective arm (118, 518, 818, 1018) of the ferrite element into a respective waveguide arm (122, 522, 822, 1022), the one or more quarter-wave transformers proximate the at least one step (116, 516, 816, 1016); each quarter-wave transformer is a quarter-wave dielectric transformer; each quarter-wave dielectric transformer is respectively attached to a distal end of each arm of the ferrite element and protrudes into a respective waveguide arm.