Abstract: An arrangement (100) for interconnection of waveguide structures (10,20) or components comprising a number of waveguide flange adapter elements (100) having a surface of a conductive material with a periodic or quasi-periodic structure (15) formed by a number of protruding elements (115) arranged or designed to allow waves to pass across a gap between a surface around a waveguide opening (3) to another waveguide opening in a desired direction or waveguide paths, at least in an intended frequency band of operation, and to stop propagation of waves in the gap in other directions.

Abstract: An arrangement for interconnecting waveguide structures or components including waveguide flange adapter elements with a surface of a conductive material with a periodic or quasi-periodic structure formed by a number of protruding elements that allows waves to pass across a gap between a surface around a waveguide opening to another waveguide opening in a desired direction or path, at least in an intended frequency band of operation, and to stop wave propagation in the gap in other directions. The arrangement includes devices for interconnecting with a waveguide flange or adapter element without requiring electrical contact and assuring that the gap is present between at least one first surface formed by periodically or quasi-periodically arranged protruding elements and a surface around a waveguide opening of the other waveguide flange, hence assuring that the first surface is not in direct mechanical contact with the other, opposite, interconnecting, waveguide flange.