a question about electrical delay
时间：03-22
整理：3721RD
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Hi, everyone. I have a question about the electrical delay related to VNA.
In doing S parameters measurement by Network Analyzer, We can get the electrical delays. The HP VNA gives the delay represented by time.
However, the output of the S parameter seems doesn't have this information of delay. If I directly using the S parameter data of the VNA to plot the smithchart in PC, it is different from what I saw in the screen.
I am wondering what's the formula to convert the S parameter data into the correct form by adjusted the electrical delay.
Thanks in advance.
In doing S parameters measurement by Network Analyzer, We can get the electrical delays. The HP VNA gives the delay represented by time.
However, the output of the S parameter seems doesn't have this information of delay. If I directly using the S parameter data of the VNA to plot the smithchart in PC, it is different from what I saw in the screen.
I am wondering what's the formula to convert the S parameter data into the correct form by adjusted the electrical delay.
Thanks in advance.
S-parameters include amplitude and phase shift or corresponding rectangular (complex) value for port S11,S21,S12,S21, and from then can calculate groupdelay. For groupdelay S21 or S12 is most intresting.
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Vipec is a open source network simulator and can import S-parameters and view in different chart including groupdelay. ie is possible to study in detail in source code to how make it.
I am not quite sure, I try to use the original data times exp(j*2*pi*f*t) for the S22, but I heard that in this case, I should use S*exp(j*4*pi*f*t). I am so confused....