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From: kr0u+@andrew.cmu.edu (Kevin William Ryan)
Newsgroups: sci.electronics,sci.physics
Subject: Re: A question about the Nyquist theorm
Message-ID: <wbk323K00WBNM2ys43@andrew.cmu.edu>
Date: 18 Feb 91 19:52:35 GMT
References: <1751@manta.NOSC.MIL> <D04gX2w163w@shark.cs.fau.edu>,
	<319@sphere.UUCP>
Organization: Biology, Carnegie Mellon, Pittsburgh, PA
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In-Reply-To: <319@sphere.UUCP>


    Mea culpa. The requirement that you must sample _above_ 2w is
correct: sampling _at_ twice the highest frequency produces indefinite
results, as phase and therefore magnitude information is lost. Thus the
proper definition is:

        max freq signal < 1/2 sampling rate

in order to preserve information. 

    It's been too damn long since that signals course... :-)

                                                    kwr

Internet: kr0u+@andrew.cmu.edu