A radar system comprising: a split-block assembly comprising a first portion (110, 152, 200) and a second portion (120, 154, 220), wherein the first portion and the second portion form a seam, wherein the first portion has a top side opposite the seam and the second portion has a bottom side opposite the seam; at least one port (144, 146, 159, 212, 462) located on the bottom side of the second portion; a plurality of dual open-ended waveguide, DOEWG, radiating elements (102, 468, 502) located on the top side of the first portion, wherein a given DOEWG radiating element comprises a section of a first horizontal waveguide channel and a second channel perpendicular to the first horizontal waveguide channel, the second channel comprising a vertical feed waveguide connected to the first horizontal waveguide channel and splitting into two parts, where each of the two parts of the second channel ends in an open ended waveguide output port configured to radiate at least a portion of electromagnetic waves that enter the given DOEWG radiating element through a first end of the first horizontal waveguide channel, the given DOEWG radiating element further comprising a reflecting component configured to reflect at least a portion of the electromagnetic waves that enter the given DOEWG radiating element into the second channel and let a remaining part of the electromagnetic waves propagate further to reach a second end of the first horizontal waveguide channel, and wherein the plurality of DOEWG radiating elements is arranged in a plurality of arrays (106, 108); and a set of waveguides (150, 202, 400) in the split-block assembly configured to couple each array to at least one of the at least one port, wherein the seam defines a center of the set of waveguides, wherein the split-block assembly comprises a polymer and wherein at least the set of waveguides, the at least one port, and the plurality of DOEWG radiating elements comprise metal on a surface of the polymer. a split-block assembly comprising a first portion (110, 152, 200) and a second portion (120, 154, 220), wherein the first portion and the second portion form a seam, wherein the first portion has a top side opposite the seam and the second portion has a bottom side opposite the seam; at least one port (144, 146, 159, 212, 462) located on the bottom side of the second portion; a plurality of dual open-ended waveguide, DOEWG, radiating elements (102, 468, 502) located on the top side of the first portion, wherein a given DOEWG radiating element comprises a section of a first horizontal waveguide channel and a second channel perpendicular to the first horizontal waveguide channel, the second channel comprising a vertical feed waveguide connected to the first horizontal waveguide channel and splitting into two parts, where each of the two parts of the second channel ends in an open ended waveguide output port configured to radiate at least a portion of electromagnetic waves that enter the given DOEWG radiating element through a first end of the first horizontal waveguide channel, the given DOEWG radiating element further comprising a reflecting component configured to reflect at least a portion of the electromagnetic waves that enter the given DOEWG radiating element into the second channel and let a remaining part of the electromagnetic waves propagate further to reach a second end of the first horizontal waveguide channel, and wherein the plurality of DOEWG radiating elements is arranged in a plurality of arrays (106, 108); and a set of waveguides (150, 202, 400) in the split-block assembly configured to couple each array to at least one of the at least one port, wherein the seam defines a center of the set of waveguides, wherein the split-block assembly comprises a polymer and wherein at least the set of waveguides, the at least one port, and the plurality of DOEWG radiating elements comprise metal on a surface of the polymer.