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Re: [Discuss-gnuradio] Re: [Openbts-discuss] how openbts set channel ban
Marcus D. Leech
Re: [Discuss-gnuradio] Re: [Openbts-discuss] how openbts set channel bandwidth?
Tue, 28 Dec 2010 20:22:31 -0500
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On 12/28/2010 08:05 PM, James Jordan wrote:
The OpenBTS software likely sets the incoming decimation rate to match
as closely as possible the desired receive bandwidth,
Hi Alexander, where the filter perform? In gnuradio?
Since there is a filter, openbts must set it, how openbts set the filter?
then it likely applies an FIR bandpass filter on the software side.
This is, after all, Software Defined Radio, so it should be no surprise
to anyone that applications (OpenBTS, or whatever) use
filters implemented in software to condition the signals before
further processing. None of that requires the analog filtering to
work in anything other than an anti-alias mode. Filtering and
bandwidth reduction is performed first in the FPGA, in the digital
domain, and then on the host, with software, again in the digital
domain. Either Gnu Radio, or OpenBTS, or whatever.
Shirleys Bay Radio Astronomy Consortium
Re: [Discuss-gnuradio] Re: [Openbts-discuss] how openbts set channel bandwidth?, Alexander Chemeris, 2010/12/29