<div><br></div>Ulrich,<div><br></div><div>Thanks for the clarification.</div><div><br></div><div>Let me rephrase my question: Given a signal already digitalized by a 16-bit@80MSPS ADC with a known noise figure (let's say 20dB). Can processing gain improve the noise figure? </div>
<div><br></div><div>73,</div><div><br></div><div>-- Edson<br><br><div class="gmail_quote">On Sun, Mar 27, 2011 at 7:58 PM, <span dir="ltr"><<a href="mailto:KA2WEU@aol.com">KA2WEU@aol.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
<div style="font-family:Arial;color:#000000;font-size:10pt"><font color="#000000" size="2" face="Arial">
<div>The formula is confusing because it calculations from the s/(n+d) backwards
the noise figure. Not well written.</div>
<div> </div>
<div>Vr= SQRT ( 4kTo times R (50 ohms) times "integrated" bandwidth ) </div>
<div> </div>
<div>find something better in the literature. The typical NF of a A/DC converter
is close to 20 dB and Zin=800 Ohm.</div>
<div>So you have tranform the 50 Ohm to 800 and you need a pr-amp, slightly more
then 15 dB.</div>
<div> </div>
<div>Look at </div>
<div> </div>
<div><a href="http://www.adat.ch/pub/Parameter_Verifikation_090305.pdf" target="_blank">http://www.adat.ch/pub/Parameter_Verifikation_090305.pdf</a></div>
<div> </div>
<div>In the non-professional area this is the absolute best design, the
explaination is in German, sorry.</div>
<div> </div>
<div>In the professional area this is the best radio </div>
<div> </div>
<div> </div>
<div> </div>
<div><a href="http://www.marcoisland.org/eb500.htm" target="_blank">http://www.marcoisland.org/eb500.htm</a></div>
<div> </div>
<div> </div>
<div>73 de Ulrich</div><div><div></div><div class="h5">
<div> </div>
<div> </div>
<div> </div>
<div> </div>
<div>
<div>In a message dated 3/27/2011 6:36:37 P.M. Eastern Daylight Time,
<a href="mailto:ewpereira@gmail.com" target="_blank">ewpereira@gmail.com</a> writes:</div>
<blockquote style="padding-left:0px;margin-left:0px"><font style="background-color:transparent" color="#000000" size="2" face="Arial">
<div><br></div>Hello Ulrich,
<div><br></div>
<div>Thanks for letting me know that my understanding is totally incorrect.
The source of my misunderstanding is Equation 8 on this paper.</div>
<div><br></div>
<div><span style="line-height:15px;border-collapse:collapse;font-family:arial, sans-serif;color:rgb(14,119,74);font-size:13px"><a style="color:rgb(0,0,204)" title="http://www.analog.com/static/imported-files/tutorials/MT-006.pdf" href="http://www.analog.com/static/imported-files/tutorials/MT-006.pdf" target="_blank">http://www.analog.com/static/imported-files/tutorials/MT-006.pdf</a></span></div>
<div><font color="#0e774a" face="arial, sans-serif"><span style="line-height:15px;border-collapse:collapse"><br></span></font></div>
<div><a title="http://www.analog.com/static/imported-files/tutorials/MT-006.pdf" href="http://www.analog.com/static/imported-files/tutorials/MT-006.pdf" target="_blank"></a><font color="#0e774a" face="arial, sans-serif"><span style="line-height:15px;border-collapse:collapse">73,</span></font></div>
<div><font color="#0e774a" face="arial, sans-serif"><span style="line-height:15px;border-collapse:collapse"><br></span></font></div>
<div><font color="#0e774a" face="arial, sans-serif"><span style="line-height:15px;border-collapse:collapse">--
Edson<br></span></font><br>
<div class="gmail_quote">On Sun, Mar 27, 2011 at 6:07 PM, <span dir="ltr"><<a title="mailto:KA2WEU@aol.com" href="mailto:KA2WEU@aol.com" target="_blank">KA2WEU@aol.com</a>></span> wrote:<br>
<blockquote style="border-left:#ccc 1px solid;margin:0px 0px 0px 0.8ex;padding-left:1ex" class="gmail_quote">
<div style="font-family:Arial;color:#000000;font-size:10pt"><font color="#000000" size="2" face="Arial">
<div>I am sorry, that is totally incorrect. The noise figure ( expressed in
dB) from the noise factor is a dimensionless value totally independent of
the bandwidth. That is the beauty of it. The Signal /(Noise +
Distortion ) value is bandwidth dependent.</div>
<div> </div>
<div>73 de Ulrich , N1UL</div>
<div> </div>
<div>
<div>In a message dated 3/27/2011 3:30:37 P.M. Eastern Daylight Time, <a title="mailto:ewpereira@gmail.com" href="mailto:ewpereira@gmail.com" target="_blank">ewpereira@gmail.com</a> writes:</div>
<blockquote style="padding-left:0px;margin-left:0px"><font style="background-color:transparent" color="#000000" size="2" face="Arial">.
Since the noise figure takes into account the
bandwidth,</font></blockquote></div></font></div></blockquote></div><br></div></font></blockquote></div></div></div></font></div>
</blockquote></div><br></div>