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<BLOCKQUOTE
style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: blue 2px solid"><FONT
style="BACKGROUND-COLOR: transparent" face=Arial color=#000000 size=2>About
the Dynamic Range of Receivers<BR><BR>It has nothing to do with the
instantaneous dynamic range, which is<BR>defining<BR>the radio's capabilty to
discern a weak signal (near the noise floor) in<BR>the<BR>presence of a much
larger signal. The maximum possible ratio of the two<BR>signal's levels
is called instantaneous dynamic range).<BR>The overall instantaneous dynamic
range of the receiver is not limited by<BR>the nyquist dynamic range of the
16-Bit ADC (about 95 dB).<BR><BR>N1UL:</FONT></BLOCKQUOTE>
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<BLOCKQUOTE
style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: blue 2px solid"><FONT
style="BACKGROUND-COLOR: transparent" face=Arial color=#000000 size=2>Please
note ADC's quantization noise having a part in the receiver's<BR>overall noise
figure (NF): At the ADC input the thermal noise from the<BR>front end and the
quantization noise will add up. To keep the ADC's part in<BR>overall NF as low
as possible (<1dB), the gain from antenna to ADC should<BR>be set so that
for the front end noise will dominate the quantization noise<BR>from ADC by
about 10 dB. This will further reduce the overall instantaneous<BR>dynamic
range of the receiver !<BR><BR>DSP is decimating the ADC sampling rate from
100 kS/sec down to rates<BR>appropriate to the actual<BR>CW / SSB signal
bandwidths of (50)300 ... 3100(4500) Hz (meaning Fs=<BR>781.25 / 1.5625
/ 3.125 / 6.25 / 12.5 kS/sec)./N1UL</FONT></BLOCKQUOTE>
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<BLOCKQUOTE
style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: blue 2px solid"><FONT
style="BACKGROUND-COLOR: transparent" face=Arial color=#000000 size=2>Noise
coming from ADC (including the quantization noise) is reduced
by<BR>just<BR>the ratio of ADC's nyquist bandwidth (=50 kHz) to the
signals bandwidth,<BR>thus<BR>giving a corresponding gain in dynamic
range of ... ><BR>>
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