Gating

Boris Dardel

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Jan 8, 2021, 1:52:50 AM1/8/21

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I measured one LAN cable with open end.

Frequencies extend fron 0 to 201MHz by steps of df=0.25MHz (n=805 points)

Reflexion sat the far end of the cable lead to an oscillation of S11at low frequency with a period of about 1MHz.

Gating should allow to remove these reflexions with a gate placed at 1e-6s.

However, when I use the gating function (low pass mode), the time span extends from -5e-7 to 5e-7s, while I expect it to extend up to 2e-6s=(n/((2n-1)*df) according to my understanding to the Math reference.

Any explanation about this limitation ?

Michael Wollensack METAS

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Jan 8, 2021, 2:08:03 AM1/8/21

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Hi,

can you please send me your S11 measurement, for example as s1p file.

Regards

Michael

Boris Dardel

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Jan 8, 2021, 2:25:12 AM1/8/21

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HEllo,

Attached a text file

Note: low frequency values were completed manually

BR.

Boris

Open DC.vdatcv.txt

Michael Wollensack METAS

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Jan 8, 2021, 3:42:26 AM1/8/21

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Hi,

you've a problem in the frequency column (not enough resolution, e.g.: 99.5 MHz, 99.8 MHz, 100 MHz, 100 MHz instead of 99.50 MHz, 99.75 MHz, 100.00 MHz, 100.25 MHz).

Regards

Michael

Boris Dardel

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Jan 8, 2021, 5:35:52 AM1/8/21

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Thanks.

I will correct that.

Best regards.
Boris

Boris Dardel

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Jan 8, 2021, 5:56:54 AM1/8/21

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Looks fine now !

However the structure I want to get rid of is in the negative times. Do you know why/what it means ?

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