white Noise

It is possible to describe white noise by a mathamatical function ??

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

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

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.

 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

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

On Fri, 18 Feb 2005 00:17:28 +0000, Rune Allnor wrote:

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> From: "Rune Allnor" <allnor@tele.ntnu.no>
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> Subject: Re: white Noise
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> 
> 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.

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