Re: [Discuss-gnuradio] Re: [Openbts-discuss] how openbts set channel bandwidth?

[Marcus D. Leech]

On 12/29/2010 01:40 AM, James Jordan wrote:
> Marcus, Thanks. I am dsp idiot, I thought decimation is only set the
> sample rate before. Didn't know it also set up a filter.
Correct decimation *requires* filtering, so that aliases don't end up in
the output sample stream.

So-called "naive" decimation, which *only* changes the sample rate, ends
up with alias frequencies
 in the output spectrum, which is definitely not what you want at all.

If you're going to be experimenting with this stuff, I'd recommend
getting a book on digital signal
 processing, or looking up some on-line tutorials.

-- 
Principal Investigator
Shirleys Bay Radio Astronomy Consortium
http://www.sbrac.org