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S21 Insertion Loss Correction

PrecisionCable can be used to remove insertion loss caused by cables or fixtures.

Previously the only way to do this analysis was to characterize the cable using

simulation, TDR, or a VNA. All of these methods can be accurate and can yield

the desired results. You would then take the newly created s-parameter file to

the oscilloscope and use the de-embedding software to remove the insertion loss

of the fixture or cable. While this method works, it requires extra equipment and

effort. PrecisionCable allows for this characterization to be done inside of the

same oscilloscope that the measurements will be taken. Characterizing the cables

and fixtures takes less than five minutes in many cases which saves significant

time.

Note: This measurement does require

access to both ends of the fixture or cable,

similar to methods such as VNA and TDR.

Figure 7. Example of frequency response

correction of a cable. The 3dB down point

moved from 21 GHz to 62 GHz.

Figure 8. PrecisionProbe corrects phase

non-linearities, notice the new flat phase.