how can we design rmsa?

Hi

The standard design formulas are available in many textbooks. Particularly the lenth of the rmsa is the determining factor for resonating frequecny. The length could be grossly approximated as

l = λo/√εr
where λo is the wavelength in free air and εr is the relative dielectric constant. However for more accurate formulas you need to take fringing field into account. The feed point in case of coaxial probe is roughly around 1/6 of length from centre.

mstripman