Lightweight Perforated Waveguide Structure Realized by 3-D Printing for RF Applications

Waveguide structures are criticized for their bulky geometry and heavy weight in practical applications. Therefore, it is necessary to investigate the weight-reduction technique of the waveguide structures, while maintaining their electrical properties and mechanical fabricability. In this paper, a waveguide perforation technique for lightweight purpose is proposed, and an X-band pyramidal horn antenna that employs this technique is developed and tested. To ease the manufacturing process of the 3-D thin-wall structure, a 3-D metal-direct-printing technology is utilized to fabricate the perforated horn. Meanwhile, a full-metal horn without any perforation and a horn printed in dielectric material but coated with metal are also included to compare with the proposed one. Experimental results show that around two-thirds of the total weight can be reduced. Other measured results in terms of electrical performance are in excellent agreement with the full-metal ones, validating the feasibility of the design and fabrication approach. The novelty of this paper realized by the 3-D printing technique is a promising strategy to inspire lightweight structure designs for radio frequency applications.