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Hello everyone,
I'm learning to use CST and I have a question about how waveguide ports work. From the official help I read that the software automatically applies to the edges of a waveguide port the same boundary conditions applied to the boundary of the entire box in which the simulation is carried out. What is a rational reason why it is right to do such a thing?
I expect that for closed waveguides, such as the coaxial or the rectangular guide, this is irrelevant, since there is the metal that intervenes first. But for open waveguides, if for example the conditions on the box are of the 'open space' type, the edges of the port become an ideal magnetic wall. Couldn't this thing 'warp' the field solution?

Thanks in advance.