Re: IQ Demod Questions

On Fri, 08 Jul 2005 09:12:27 -0400, David Kirkland <spam@xxxxxxxxxxxx>
wrote:

(snipped)
>>
>Hi Guys,
>
>I wasn't able to look able to find the source for this that I was
>thinking of. I was able to find adescription of the technique in
>Crochiere and Rabiner's book "Multirate Digital Signal Processing".
>There is also a similar section in Whalen's Book "Detection of Signals
>in Noise"
>
>First, by related I meant in terms of computational savings. The
>technique I mentioned doesn't give the full I/Q samples - the signal
>still stays real (if it started that way). Essentially the left edge of
>the +ve freq components are moved down close to the right side of zero,
>and the right edge of the -ve freq components are moved down close to
>the left side of 0. Moving them close to 0 prevents them from overlaping
>and causing corruption.

Hi David,

Ah, I misunderstood you.
When I first learned about it, I thought the freq translation
method that you descibe was pretty neat.
Neat enough that I covered that topic in the
2nd edition of my DSP book.

Thanks David,
[-Rick-]

(snipped)


.

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