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Discussion of precise time and frequency measurement

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Frequency Counter Choice

GB
Giorgio Barinetti
Fri, Oct 23, 2020 9:34 AM

Hi Attila,

Thanks for the very nice job. I’ll sharpen out my math and try to read it 😊

Regards,

Giorgio.

On Thu, 22 Oct 2020 13:29:07 -0400

Bob kb8tq <kb8tq at n1k.orghttp://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com> wrote:

There is a paper running around behind the IEEE paywall by Collins that details

one approach to designing multi-stage limiters. There are other ways to do it.

The key is to not go to crazy all in one stage.

<self-advertisment>

You can find a modern, more accurate version of Collins result

in [1]. While most formulas in there give the noise up to some

proportionality factor, all the information to calculate the noise

level is in there. The big difference to Collins here is that this

result is exact if you use all harmonics up to infinity (which is

easy) or can break up with a known error if you don't want to go

that far. Collins uses a trapezoid approximation throughout and thus

over-estimates the noise contribution of low-gain stages, which

are the first stages thus contribute to a relatively large error

in the calculation.

</self-advertisment>
                   Attila Kinali

[1] "A Physical Sine-to-Square Converter Noise Model"

by yours truly, IFCS 2018

http://people.mpi-inf.mpg.de/~adogan/pubs/IFCS2018_comparator_noise.pdf

--

<JaberWorky>  The bad part of Zurich is where the degenerates

            throw DARK chocolate at you.
Hi Attila, Thanks for the very nice job. I’ll sharpen out my math and try to read it 😊 Regards, Giorgio. On Thu, 22 Oct 2020 13:29:07 -0400 Bob kb8tq <kb8tq at n1k.org<http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com>> wrote: > There is a paper running around behind the IEEE paywall by Collins that details > one approach to designing multi-stage limiters. There are other ways to do it. > The key is to not go to crazy all in one stage. <self-advertisment> You can find a modern, more accurate version of Collins result in [1]. While most formulas in there give the noise up to some proportionality factor, all the information to calculate the noise level is in there. The big difference to Collins here is that this result is exact if you use all harmonics up to infinity (which is easy) or can break up with a known error if you don't want to go that far. Collins uses a trapezoid approximation throughout and thus over-estimates the noise contribution of low-gain stages, which are the first stages thus contribute to a relatively large error in the calculation. </self-advertisment> Attila Kinali [1] "A Physical Sine-to-Square Converter Noise Model" by yours truly, IFCS 2018 http://people.mpi-inf.mpg.de/~adogan/pubs/IFCS2018_comparator_noise.pdf -- <JaberWorky> The bad part of Zurich is where the degenerates throw DARK chocolate at you.