Reply by Bob Cain February 23, 20052005-02-23

Robin Clark wrote:

> True. Or to say that the FFT of the white noise sample should contain > all frequencies.
Is the DFT of a one sample pulse then white noise? :-) I.e., your condition is necessasary but not sufficient. Bob -- "Things should be described as simply as possible, but no simpler." A. Einstein
Reply by Robin Clark February 21, 20052005-02-21
On Fri, 18 Feb 2005 00:17:28 +0000, Rune Allnor wrote:

> Path: > newsbe2-gui.ntli.net!newspeer1-win.ntli.net!news-out.ntli.net!newsrout1-gui > .ntli.net!ntli.net!pe1.news.blueyonder.co.uk!blueyonder!pe2.news.blueyonder > .co.uk!blueyonder!proxad.net!proxad.net!216.239.36.134.MISMATCH!postnews.go > ogle.com!o13g2000cwo.googlegroups.com!not-for-mail > From: "Rune Allnor" <allnor@tele.ntnu.no> > Newsgroups: comp.dsp > Subject: Re: white Noise > Date: 18 Feb 2005 00:17:28 -0800 > Organization: http://groups.google.com > Lines: 27 > Message-ID: <1108714648.131147.157470@o13g2000cwo.googlegroups.com> > References: <cv1qs4$9uv$1@rzsun03.rrz.uni-hamburg.de> > <1108641498.680806.320920@c13g2000cwb.googlegroups.com> > <1108644282.360825.175590@c13g2000cwb.googlegroups.com> > NNTP-Posting-Host: 193.71.9.232 > X-Trace: posting.google.com 1108714652 16781 127.0.0.1 (18 Feb 2005 08:17:32 > GMT) > X-Complaints-To: groups-abuse@google.com > NNTP-Posting-Date: Fri, 18 Feb 2005 08:17:32 +0000 (UTC) > In-Reply-To: <1108644282.360825.175590@c13g2000cwb.googlegroups.com> > User-Agent: G2/0.2 > Complaints-To: groups-abuse@google.com > Injection-Info: o13g2000cwo.googlegroups.com; posting-host=193.71.9.232; > posting-account=ufFYdQwAAAA_zWZBwYAkRO8kgyInHw79 > Xref: newspeer1-win.ntli.net comp.dsp:170814 > X-Received-Date: Fri, 18 Feb 2005 08:16:26 GMT (newsbe2-gui.ntli.net) > MIME-Version: 1.0 > Content-Type: text/plain; charset=iso-8859-1 > > > > bryant_j_j@yahoo.com wrote: >> no, his question is not clear at all. > > Agreed. > >> what does he mean by "describe >> white noise by a mathamatical function", is it a mathematical > function >> for every sample path of a discrete-time white noise process or a >> description of the autocorrelation function. the first is impossible > to >> do. > > Wrong. It is possible to describe white noise as > > "a time sequence/function that is drawn from a statistical > distribution that has the statistical propaerties of white > noise" > > and write it in mathemathical symbolic lingo. That would, technically > speaking, be a "mathemathical description of white noise". Whether > the description would be *useful* for anything, is a completely > different question. > > Rune
True. Or to say that the FFT of the white noise sample should contain all frequencies.
Reply by Rune Allnor February 18, 20052005-02-18
bryant_j_j@yahoo.com wrote:
> no, his question is not clear at all.
Agreed.
> what does he mean by "describe > white noise by a mathamatical function", is it a mathematical
function
> for every sample path of a discrete-time white noise process or a > description of the autocorrelation function. the first is impossible
to
> do.
Wrong. It is possible to describe white noise as "a time sequence/function that is drawn from a statistical distribution that has the statistical propaerties of white noise" and write it in mathemathical symbolic lingo. That would, technically speaking, be a "mathemathical description of white noise". Whether the description would be *useful* for anything, is a completely different question. Rune
Reply by Abdul February 17, 20052005-02-17
 white noise generated by the pseudo random generator has an autocorrelation
function as an Impulse. So, Mathematically can we describe pseudo random
noise wtih an Impulse ??.

"Gary Marsh" <dont@spam.me.plz> schrieb im Newsbeitrag
news:Eh0Rd.49605$K54.31711@edtnps84...
> Abdul wrote: > > It is possible to describe white noise by a mathamatical function ?? > > Depends on your definition of noise. > > True random noise? no, you can't mathematically represent it. > > Noise produced by a pseudo-random number generator of some sort? yes, > represent it using the mathematical function which implements the PRNG. > > GM
Reply by February 17, 20052005-02-17
no, his question is not clear at all. what does he mean by "describe
white noise by a mathamatical function", is it a mathematical function
for every sample path of a discrete-time white noise process or a
description of the autocorrelation function. the first is impossible to
do.

Reply by Gary Marsh February 17, 20052005-02-17
Abdul wrote:
> It is possible to describe white noise by a mathamatical function ??
Depends on your definition of noise. True random noise? no, you can't mathematically represent it. Noise produced by a pseudo-random number generator of some sort? yes, represent it using the mathematical function which implements the PRNG. GM
Reply by Rune Allnor February 17, 20052005-02-17
Abdul wrote:
> It is possible to describe white noise by a mathamatical function ??
Yes. I could elaborate provided you give a very convincing argument that your question has nothing to do with any kind of homework. Rune
Reply by Abdul February 17, 20052005-02-17
It is possible to describe white noise by a mathamatical function ??