What is a Nyquist in Terms of Frequency?

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The discussion centers on the definition of "Nyquist" in relation to frequency, particularly in digital signal processing. Participants clarify that while "Nyquist frequency" is a standard term related to sampling rates, the term "a Nyquist" is not commonly recognized or defined in literature. The conversation suggests that the term may be a creative or informal usage rather than an established concept. It emphasizes that frequency is often measured relative to the Nyquist frequency, which is crucial in understanding sampling theory. Overall, the term lacks formal recognition in the context discussed.
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Can anyone tell me the definition of a "Nyquist" with respect to units of frequency? I didn't find it defined on the web. I presume it is some measure of cycles/sample or similar

Thanks
Fritz
 
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fsonnichsen said:
Can anyone tell me the definition of a "Nyquist" with respect to units of frequency?
It isn't. But I can see that a creative author might decide he can use it as a measure of the ratio of two frequencies.

Do you have a reference to where you found it? Some topic dealing with sampling an analog signal, I presume.
 
This was in a draft of a textbook. I tend to agree with your premise that this is a "home spun" term.

Thanks
Fritz
 
In digital signal processing it is quite common to measure frequency relative to the Nyquist frequency (which depends on the sample rate of course). That is no different from other dimensionless quantities used in physics (e.g. Reynolds number).

But I've never seen the term "a Nyquist" used.
 

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