[hpsdr] Perseus is a reality

[Don Ward]

>> That does make sense; I hadn't really thought about the fact that it's
>> down_sampling_ as well as downconverting.  The gain is more like 4-5 bits 
>> in
>> that example (10*log(downsampling factor) dB, rather than 20), but still
>> very much worthwhile.
>
> Why 10*log ? Aren't we talking about the _voltage_ that can be represented 
> with 16 or 24 bits ?

You get 20*log gain in the signal, but 10*log gain in the quantization 
noise, for a net gain in S/N or dynamic range of 10*log.  The output can be 
scaled so the 10*log gain in S/N is kept while the additional 10*log gain in 
noise is thrown away.

-- Don W.


 1192056090.0