Fabrication of a High-Efficiency Waveguide Antenna Array via Direct Metal Laser Sintering

The direct metal laser sintering (DMLS) technique, using aluminum alloy, is adopted to fabricate a relatively large 8x8 wideband multilayer waveguide array with an integrated corporate-fed network in the Ku-band. This DMLS technique offers the flexibility to fabricate waveguide structures with complicated embedded structures with good reliability and high precision. It is favorably compared to the time-consuming machining technique when the array must be built in separate pieces and secured together. Experimental results show there is dB gain improvement compared to one that is fabricated by machining technique. Antenna aperture efficiency is higher than 80% over a wide operational bandwidth and even exceeding 90% at most frequencies. This work shows that the metal-direct-printing technique is a promising manufacturing method for the fabrication of complicated waveguide antenna arrays.