Hi Maha,

Are you using a electromagnetic software? If you use for example HFSS you need to increase the number of maximum pass to ensure convergence.

If you use a software based on time domain method, you may need to increase the total number of iteration.

This is  theoretical Maha,

1.Ripples occur due to reflection , have you estimated the coupling coefficient ?

2. With a fixed Z0, Q will give you a measure (load vs unloaded)

3.The S11 and S21 should tell you (variance) for a frequency (or range of it)

Hello Maha,

Check the attached document. It contains useful informations about ripple reduction in S-parameter.

B-regards