A system comprising: a phased array antenna subarray tile assembly comprising: a printed wiring board, PWB, comprising a plurality of layers and a plurality of antenna integrated printed wiring board, AiPWB, waveguides ; an integrated circuit die coupled to a first surface of the PWB; an antenna element included in one of said AiPWB waveguides and coupled to a second surface of the PWB; a first conductive via having a first diameter, the first conductive via being coupled to the integrated circuit die and extending through a first subset of the layers ; a second conductive via having a second diameter larger than the first diameter, the second conductive via being offset from the first conductive via, extending through a second subset of the layers , and being coupled to the antenna element; a conductive trace of the PWB coupled to the first and second conductive vias, wherein the offset of the second conductive via provides a thermal mechanical stress relief to the integrated circuit die; a metallic honeycomb structure ; a plurality of cylindrical waveguides formed within the metallic honeycomb structure, wherein each cylindrical waveguide is coupled to a corresponding AiPWB waveguide of the plurality of AiPWB waveguides and has a radius that is substantially equal to a radius of the corresponding AiPWB waveguide; and a recess formed along a surface of each of the cylindrical waveguides, wherein the cylindrical waveguides and the recesses are filled with a dielectric material, and wherein each filled recess mechanically secures the dielectric material to the cylindrical waveguide, wherein the dielectric material has a coefficient of thermal expansion, CTE, substantially equal to a CTE of the metallic honeycomb structure; and the dielectric material has a dielectric constant substantially equal to a dielectric constant of the PWB, and wherein the metallic honeycomb structure includes aluminum. a printed wiring board, PWB, comprising a plurality of layers and a plurality of antenna integrated printed wiring board, AiPWB, waveguides ; an integrated circuit die coupled to a first surface of the PWB; an antenna element included in one of said AiPWB waveguides and coupled to a second surface of the PWB; a first conductive via having a first diameter, the first conductive via being coupled to the integrated circuit die and extending through a first subset of the layers ; a second conductive via having a second diameter larger than the first diameter, the second conductive via being offset from the first conductive via, extending through a second subset of the layers , and being coupled to the antenna element; a conductive trace of the PWB coupled to the first and second conductive vias, wherein the offset of the second conductive via provides a thermal mechanical stress relief to the integrated circuit die; a metallic honeycomb structure ; a plurality of cylindrical waveguides formed within the metallic honeycomb structure, wherein each cylindrical waveguide is coupled to a corresponding AiPWB waveguide of the plurality of AiPWB waveguides and has a radius that is substantially equal to a radius of the corresponding AiPWB waveguide; and a recess formed along a surface of each of the cylindrical waveguides, wherein the cylindrical waveguides and the recesses are filled with a dielectric material, and wherein each filled recess mechanically secures the dielectric material to the cylindrical waveguide, wherein the dielectric material has a coefficient of thermal expansion, CTE, substantially equal to a CTE of the metallic honeycomb structure; and the dielectric material has a dielectric constant substantially equal to a dielectric constant of the PWB, and wherein the metallic honeycomb structure includes aluminum. <EOS>