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Discussion of precise time and frequency measurement

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Fwd: Two questions about counters

EK
Erik Kaashoek
Thu, Sep 7, 2023 6:08 AM

See forwarded message from Enrico Rubiola.
Erik

-------- Forwarded Message --------

Erik,
I got your message from JMF (CC), be free to forward to the time nuts list.

First question.
We work with equally spaced time stamps of the incoming signal.
Basically, the LR gives a straight line like y = a*x + b (high-school
notation).
The enhanced resolution counter estimates b, which is the average
frequency in the measurement interval if the origin of the xy plane is
chosen appropriately.
The LR counter estimates a, which is the a
The LR has approx 1.5 dB better rejection of noise (better estimation of
frequency)

There is an updated version of the slideshow you mention, split between
https://rubiola.org/pdf-lectures/Scientific%20Instruments%20L01-05,%20Instruments.pdf
https://rubiola.org/pdf-lectures/Scientific%20Instruments%20L06-10,%20Oscillators.pdf
(open lectures for PhD students and young scientists)

Look at p.48 and p.50 of the 2nd slideshow.

I can't answer your second question now.

--
Enrico Rubiola
https://rubiola.org
https://efts.eu

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See forwarded message from Enrico Rubiola. Erik -------- Forwarded Message -------- Erik, I got your message from JMF (CC), be free to forward to the time nuts list. First question. We work with equally spaced time stamps of the incoming signal. Basically, the LR gives a straight line like y = a*x + b (high-school notation). The enhanced resolution counter estimates b, which is the average frequency in the measurement interval if the origin of the xy plane is chosen appropriately. The LR counter estimates a, which is the a The LR has approx 1.5 dB better rejection of noise (better estimation of frequency) There is an updated version of the slideshow you mention, split between https://rubiola.org/pdf-lectures/Scientific%20Instruments%20L01-05,%20Instruments.pdf https://rubiola.org/pdf-lectures/Scientific%20Instruments%20L06-10,%20Oscillators.pdf (open lectures for PhD students and young scientists) Look at p.48 and p.50 of the 2nd slideshow. I can't answer your second question now. -- Enrico Rubiola https://rubiola.org https://efts.eu | \ | \ | \ | *. | * . _ _ _ _ _ _ |___ ___ ___ ___ ___ ___