When we design and simulate waveguides we should attend that path input source waveguide is very important, that can make high efficiency coupling and low loss, we know that matching and coupling is very vital in Electronic and RF Devices.In waveguide excitation point is called waveguide flange in this post we want to discuss about it.
For waveguide flange calling we have two standard American standard and Europen stabdard,we usally use american standard, so for our waveguide we should select a type of flange. you can see in below images American and Europen standards.
In this link flange is defined:
A waveguide flange is a connector for joining sections of waveguide, and is essentially the same as a pipe flange—a waveguide, in the context of this article, being a hollow metal conduit for microwave energy. The connecting face of the flange is either square, circular or (particularly for large or reduced-height rectangular waveguides), rectangular. The connection between a pair of flanges is usually made with four or more bolts, though alternative mechanisms, such as a threaded collar, may be used where there is a need for rapid assembly and disassembly. Dowel pins are sometimes used in addition to bolts, to ensure accurate alignment, particularly for very small waveguides.
Fig1:American standard waveguide flange
Fig2:Europen standard waveguide flange
We now familiar with type of flanges, ussually and easy way we use SQ_Cover ATM”-6″.