On Apr 9, 5:22?am, wrote:
I need to match the impedances of waveguide form microwave oven to the
resonant cavity which will be hollow cylinder. Do you know how to
calculate the dimensions of both to have best impedance matching?

Kind regards
Jakub

Yes, but the answer is VERY long and depends on the MODE of
excitation of the cavity resonator. Depending on the dimensions
of the cavity and the excitation point - and kind of coupling - there
could be 6 to 8 different EM field configurations. You will have to
consult a microwave components basic text to learn about the
various modes in a cavity...and the ways to couple RF energy
into the cavity to achieve each mode.

I am not being evasive here. The answer is NOT a simple one.
The 1 to 2 GHz frequency range is a sort of "transition" from
lumped constants (conventional resistors, capacitors, inductors)
to "distributed constants," where the Fields and Waves and their
excitation-pickoff dominate...on up to the top of microwaves.

It's been about 30 years since I was really active in microwaves
from 1 to 25 GHz and I'm a bit rusty on that...but the ways it
is handled remains the same and found in many textbooks,
old to new. My particular "bible" on microwave structures is
"Microwave Filters, Impedance-Matching Networks, And
Coupling Structures," by George Matthaei, Leo Young, and
E.M.T.Jones, McGraw-Hill 1964.

73, Len AF6AY