Apr 30, 2012 #1 SeriousTyro Member level 2 Joined Apr 5, 2010 Messages 49 Helped 1 Reputation 2 Reaction score 1 Trophy points 1,288 Activity points 1,620 I measured the S21 and converted it to Z params and plotted it. I understand how before the resonant frequency, the capacitance dominates then after resonance the inductance dominates. I don't understand the second dip at around 1GHz. Why does it go back down?
I measured the S21 and converted it to Z params and plotted it. I understand how before the resonant frequency, the capacitance dominates then after resonance the inductance dominates. I don't understand the second dip at around 1GHz. Why does it go back down?
Apr 30, 2012 #2 FvM Super Moderator Staff member Joined Jan 22, 2008 Messages 52,409 Helped 14,749 Reputation 29,780 Reaction score 14,095 Trophy points 1,393 Location Bochum, Germany Activity points 298,048 You didn't clarify the measurement setup. Assuming a LC series circuit connected between port 1 and port 2, you see the inductor self resonance around 1 GHz.
You didn't clarify the measurement setup. Assuming a LC series circuit connected between port 1 and port 2, you see the inductor self resonance around 1 GHz.
Apr 30, 2012 #3 D.A.(Tony)Stewart Advanced Member level 7 Joined Sep 26, 2007 Messages 9,004 Helped 1,823 Reputation 3,645 Reaction score 2,197 Trophy points 1,413 Location Richmond Hill, ON, Canada Activity points 59,563 all components tend to have SRF elements, even very carefully controlled impedances and transmission lines. Can you display S11 to see if there is zero on the input that created a pole on S21?
all components tend to have SRF elements, even very carefully controlled impedances and transmission lines. Can you display S11 to see if there is zero on the input that created a pole on S21?