Article View: sci.electronics
Article #10302Re: A question about the Nyquist theorm
From: Robert McGwier
Date: Wed, 20 Feb 1991 16:06
Date: Wed, 20 Feb 1991 16:06
24 lines
1503 bytes
1503 bytes
From article <6607@healey>, by grayt@Software.Mitel.COM (Tom Gray):
> This is a common misconception. The sampling pulses are of finite widht.
> The shape of the wave is preserved within the sampling pulse. This
> information allows representation of a signal at exactly 1/2
> the Nyquist freqency.
>
> Most text books play fast and lose with Nyquist.
I pose the following question. Suppose you are sampling at rate N samples
per second, and you see a constant value V for your A/D sample. Is the
frequency of the signal which produced those samples 0 or N/2? Since
I obviously posed this question because I know you CANNOT discriminate
between these two cases, what exactly is it then that Nyquist IS telling
us and am I asking about apples and oranges?
Bob
--
____________________________________________________________________________
My opinions are my own no matter | Robert W. McGwier, N4HY
who I work for! ;-) | CCR, AMSAT, etc.
----------------------------------------------------------------------------
Technical Details
Message-ID:
<883@idacrd.UUCP>Path:
arc1-ca.pugleaf.net!utzoo!utgpu!news-server.csri.toronto.edu!bonnie.concordia.ca!thunder.mcrcim.mcgill.edu!snorkelwacker.mit.edu!spool.mu.edu!sdd.hp.com!wuarchive!udel!princeton!idacrd!macReferences:
<6607@healey>Show Full Headers
Complete Article Headers
Path: arc1-ca.pugleaf.net!utzoo!utgpu!news-server.csri.toronto.edu!bonnie.concordia.ca!thunder.mcrcim.mcgill.edu!snorkelwacker.mit.edu!spool.mu.edu!sdd.hp.com!wuarchive!udel!princeton!idacrd!mac From: mac@idacrd.UUCP (Robert McGwier) Newsgroups: sci.electronics,sci.physics Subject: Re: A question about the Nyquist theorm Message-ID: <883@idacrd.UUCP> Date: 20 Feb 91 16:06:39 GMT References: <6607@healey> Organization: idacrd, princeton, nj Lines: 24