Re: microstrip transmission line

what is the value of impedance in ohm for microstrip transmission line that is considered as i) open circuit (infinity ohm) and ii) short circuit ( zero ohm)

Added after 3 minutes:

in addition of previous question.. The impedance at frequency 2GHz, 4GHz, 8GHz, 12GHz and 20GHz.

Your question suggests that you do not understand transmission line theory. Suggest you search open circuited stubs and short circuited stubs. The answer involves the tangent function.

That is if the transmission line is assumed to be lossless. If it is lossy then the answer involves the hyperbolic tangent function.

I want to design a harmonic resonator that will become open circuit for a certain frequency(even harmonic) and short circuit at a certain frequency (odd harmonic).
From my design simulation, at the operating freq (2GHz), Zin=50ohm. at second harmonic freq ( 4GHz), Zin = 8ohm and at third harmonic freq (6GHz) Zin=10k ohm.
again at 4th harmonic (8GHz), Zin = 9ohm and 5th harmonic (10GHz), Zin = 8k ohm.
my question is, Can I consider Zin = 8ohm and 9ohm as short circuit and also Zin= 10k ohm and 8k ohm as open circuit?

Of course you will never get 0ohms or infinite ohms.

The question is how much rejection and/or inertion loss you need at your harmonics.

It depends on what you are trying to do. If you are expecting the 8 ohms to filter one of the harmonics, 8 ohms to ground is not going to give you very many dB's of rejection.