• swadesh
    1
    I am trying to do some free space calibration to extract material data from unknown arbitrary material. I am struggling with the calibration part as the s parameters i am getting is not good enough to get proper value. Can anybody please suggest the calibration procedure?
    I have E8361 keysight VNA. I have Type N short, open, load, through (50ohm) but no standard precise calkit. What should I do?
  • Yassen Mikhailov
    1
    Dear Swadesh,

    I would recommend that you perform a free space TRL calibration. The through is simply the distance between the two ports (antennas) without any sample. Reflect is a reflective plate in the sample holder. Line is the additional distance between the two ports depending on the measurement frequency - take the quarter wavelength of the mid-band frequency and move the second antenna by the corresponding length - example X-band - 9 GHz - 8 mm = line is through length + 8 mm.

    Make sure you specify a sexless connector with a characteristic impedance of 377 Ohms.

    Hope this helps.


    Yassen
bold
italic
underline
strike
code
quote
ulist
image
url
mention
reveal
youtube
tweet
Add a Comment

Welcome!

Join the international conversation on a broad range of microwave and RF topics. Learn about the latest developments in our industry, post questions for your peers to answer, and weigh in with some answers if you can!