? why you recommend don't use smooth funciton average function
ans: If you use 1kHz IF BW or lower, have a good low noise VNA like ZVA-40 you do not need it, and it masks resonance in systems. Some VNA's store the touchstone with S-parameter smoothing which creates problems. You can post process smooth using Matlab very eaisly. I only smooth group delay btw. Have a plot of this in day 3 I believe.