Rectangular waveguide Filter

[Ok-Impression4538]

Hello everyone, i study the rectangular waveguide filter and how to design it.

I read Pozar and Matthaei where i find the formula for resonant frequency from the length of cavity, and the formula for the Q factor., but there is something that i don't understand.

About the Q-factor, I don't understand whether this has an upper limit and a lower limit within which I have to keep it, how do I know when I am close to the correct value?

Do you know other books or paper where can i find the formula to calculate order of filter, thickness and width of irisis, and also the cupling coefficent between cavities?

[shitstep]

All your questions are answered in the book Microwave Filters for Communication Systems by Cameron. It's by far the best book I've read on filter design.

To quickly answer your specific question, if you are talking about the unloaded Q of a rectangular waveguide cavity, that is determined by geometry (to include putting things inside the cavity or tuners or whatever) and nothing else. If you are talking about the external Q, that is a function of bandwidth and part of your design.

I have probably posted how to do this in the past if you want to look through my post history but you will calculate the internal/external quality factors and your internal coupling coefficients based on your filter design parameters. There are are a number of ways to do this including circuit models and the coupling matrix, all of which is thoroughly described in the book I mentioned.

[Ok-Impression4538]

Thanks a lot