Phase unwrapping of S2,1

[RandomZed]

Hello,
I ran a simulation where I got S11 and S21 values. I'm interested in the S21 phase values but having difficulties understanding how to unwrap the S21 phase graph.
Any help on how to unwrap a phase value and what criteria do I have to meet would be appreciated.
For example, how will I unwrap the phase value at 2.45 GHz and how to also do it at 2.53 GHz

Thanks in Advance.

 

[D.A.(Tony)Stewart]

You cannot get absolute phase unless you sweep from a lower f where the phase is stable either 0 or 180 deg.

This plot shows d phi/ df = 1 cycle of 360 deg for a range of about 370 MHz. This is group delay = 1/delta f = 2.7 ps

This might be normal if it were a >= 12th order Gaussian or Linear Phase BPF.

Try to plot the group delay

 

[RandomZed]

You cannot get absolute phase unless you sweep from a lower f where the phase is stable either 0 or 180 deg.

This plot shows d phi/ df = 1 cycle of 360 deg for a range of about 370 MHz. This is group delay = 1/delta f = 2.7 ps

This might be normal if it were a >= 12th order Gaussian or Linear Phase BPF.

Try to plot the group delay

Thanks for the reply, I tried simulating in a frequency range of 0 and 3 GHz and got the attached resutls.
I also plotted the Group Delay and attached the result as well.

Your help is appreciated

 

[BigBoss]

S-parameters can have a Phase between -pi and +pi radian. So This is the Definition.

 

[D.A.(Tony)Stewart]

It appears you may have not nulled out your fixture delay by calibration . It is perhaps < 2ns fixed which is included with unknown D.U.T. group delay. But I don't know what you are testing.