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<tt>Johannes,<br>
The digital down-conversion occurs in the hardware (in the
FPGA). The resulting I & Q values are then transmitted to the
PC via USB or Ethernet. I don't have KK source code available at
the moment, so I can't comment on the note you quoted. The I
& Q data include the full bandwidth associated with the
selected sampling rate. Digital filtering is applied around zero
frequency to select the signal at the center of the downconverted
band. Other signals within this bandwidth are eliminated. It
would be possible to do a second digital down-conversion (in the
PC) of these signals, shifting them to zero frequency, rather than
changing the hardware digital downconversion.<br>
</tt><br>
73,<br>
Dave<br>
WA8YWQ<br>
<br>
On 7/27/2013 8:19 AM, Johannes Sedlmeier wrote:
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<pre wrap="">***** High Performance Software Defined Radio Discussion List *****
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<div>Hello everyone,<br>
<br>
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I'm an RF engineer from Germany and I am currently working to
fit the KISS KONSOLE program to my needs.<br>
<br>
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I wondered, if there is a proper downconversion done somewhere
in the code. I could not find anything, except a note from the
programmer in "EthernetDevice.cs" that says, that <br>
<br>
<pre style="font-family:Consolas;color:black;background:none repeat scroll 0% 0% white"><span style="color:green"> //temporary -- soon will do digital down-conversion</span>
<span style="color:green">// with sin & cos, so we'll actually have I & Q data to enter.
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<pre style="font-family:Consolas;color:black;background:none repeat scroll 0% 0% white"><span style="color:green"><span style="background-color:rgb(0,0,0)"><span style=""></span></span><font color="#000000">So it seems, that only the Real Part of the received signal is used. Is this correct or am I missing something?
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<pre style="font-family:Consolas;color:black;background:none repeat scroll 0% 0% white"><span style="color:green"><font color="#000000">Thanks in advance, I really appreciate your work you have done so far on the HPSDR-Project.
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<pre style="font-family:Consolas;color:black;background:none repeat scroll 0% 0% white"><span style="color:green"><font color="#000000">Greetings,
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<pre style="font-family:Consolas;color:black;background:none repeat scroll 0% 0% white"><span style="color:green"><font color="#000000">Johannes Sedlmeier
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