On Fri, Jan 21, 2011 at 11:11 AM, Marcus D. Leech
<address@hidden> wrote:
On 01/20/2011 09:42 PM, James Jordan wrote:
> Hi Tom,
> This is very old topic. I have read a DSP book. But I find that I
> still not very understand channelizer.
> Why in channelizer use low pass filter, in my imagine channelizer will
> use band pass filter to filter each
> channel like that: 600Mhz baseband signal have 4 channel each channel
> have 100Khz bandwidth.
> so the channel freq is: 599.8Mhz 599.9Mhz 600Mhz 600.1Mhz. So I need 4
> bandpass filter to filter each
> channel but actually the channelizer use lowpass filter, so why?
>
>
I know you've asked Tom, but he's on the road. I haven't looked at the
Gnu Radio channelizer, but one
way to implement a channelizer is to convert all the signals to
baseband, then low-pass filter.That
way, all channels are at baseband when you're done.
Does that make sense?
--
Principal Investigator
Shirleys Bay Radio Astronomy Consortium
http://www.sbrac.org