Understanding the fixture deembeding method being reccomended

[yefj]

Hello, there are many fixture removing methods .
I got this keysight support answer for my N5224B PNA.
I know there is 2X method, 1x Reflect Method.
What method did he meant in his explanation?
Thanks.

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Please follow the following link to our help files Manual:

https://helpfiles.keysight.com/csg/N52xxB/S3_Cals/Auto_Fixture_Removal.htm



To effectively use the Automatic Fixture Removal (AFR) feature on the N5224B PNA, please follow these key steps:

1. Fixture Requirements:
   • Ensure that the fixture insertion loss is less than 10 dB.
   • Ensure that all fixtures are 50 ohms.
   • Fixture return loss should be significantly less than 17 dB.
2. Measurement Setup:
   • For one-port AFR, measure the fixture with the far end looking into an open.
   • If possible, create a similar fixture with the DUT removed and insert a short at the far end for a more accurate measurement.
3. Frequency Considerations:

• AFR basic requirement is that the Electrical Length (
  
  ) of the fixture to be de-embedded should be greater than 4 times the Rise Time (
  

(BW is the frequency range of the VNA in use 43.5GHz for N5244B)

So, if you use N5224B. the minimum fixture

can be < 22pS

• Measure at a higher frequency than necessary. For example, if your requirement is 20 GHz then measure to 26 GHz. This expanded frequency coverage provides an extra margin for the AFR conversion algorithms to operate. A general rule of thumb is to measure 10% higher in frequency than the top frequency is needed.
• For one port AFR, use an open, or a short or both
• Be sure that your Start frequency is the same as the Frequency Step points. If the Start frequency is 10 MHz, the Frequency step should be 10 MHz.