Abstract: | In this article, a coaxial probe‐fed open‐ended waveguide filtering antenna with all‐in‐one structure is proposed and fabricated by adopting sand casting process. It is known that for waveguide component with complex internal space, detached parts, and post‐processing assembly are often necessary, while unavoidably resulting in error, air gap and loss. In this context, sand casting process is here utilized to fabricate the whole waveguide structure directly, thus achieving a fully integrated antenna. Besides, by controlling the external couplings from probe feed and free space, the proposed coaxial probe‐fed antenna can provide similar impedance matching to a waveguide‐fed three‐order waveguide filter. Both the frequency‐ and time‐domain reflection coefficients of filter and antenna have been compared and analysed. An antenna prototype is fabricated and measured to validate the proposed design, which provides a successful example of all‐in‐one waveguide filtering antenna. |