A procedure to correct the response of manufactured Groove Gap Waveguide components

At mm-wave band, rectangular waveguide (RWG) based components are susceptible to suffer response degradation originated by bad metal contact at junctions due to the metal roughness. The Groove Gap Waveguide (GGW), which behaves similarly to the RWG, but is formed by two independent pieces that do not require metal contact, solves this problem. However, response deviation due to manufacturing tolerances, common for any topology at mm-wave band, is still a problem to address. This work presents a procedure to correct GGW components response after the manufacturing process. This procedure exploits the interesting GGW feature of having a simple top piece, consisting in a bare metal plate, which can be easily re-manufactured and replaced. Several metal insertions can be disposed on this plate, being the insertion height optimized at each iteration by an Aggressive Space Mapping (ASM) procedure. As an example, the response of a narrow-band passband filter is successfully corrected.