Multilayer waveguide comprising at least one transition device between layers of this multilayer waveguide

A method for manufacturing a multilayer electromagnetic waveguide comprising:

• superimposing several layers forming to form channels for guiding an electromagnetic wave;
• and
• providing at least one transition device comprising at least one dielectric interlayer between two guide channels, provided as coupled guide channels, extending according to a direction of transmission of an electromagnetic wave between the coupled guide channels via the transition device.
• wherein each transition device comprises at least one adaptation channel extending from the coupled guide channels, according to a longitudinal direction secant to the transmission direction,
• wherein each adaptation channel is delimited by at least two electrically-conductive walls, provided as adaptation walls, spaced from each other by the dielectric interlayer of the transition device,
• wherein each adaptation wall extends according to the longitudinal direction along the dielectric interlayer from one end, provided as a coupling end, of a coupled guide channel, and at least one adaptation wall extending according to the longitudinal direction over a length selected so as to obtain an impedance, provided as input impedance, at least substantially zero between the adaptation walls of the adaptation channel at the level of the coupling ends of the coupled guide channels to optimize the transmission of an electromagnetic wave between the two coupled guide channels.