This paper presents a 61 GHz narrow-band filter, implemented with Groove Gap Waveguide (GGW) coupled resonators. This structure does not require metal contact on the side walls and, therefore, is very ...

Full tutorial video link above the title wire size to make ring diameter 1,5cm (can + a few centimeters to depreciate) 19 gauge ( wire diameter 0.9mm ) : 13cm( 5 inch) 24 gauge ( wire diameter 0.5mm ) ...