SDR bit resolution vs. spectrum dynamic range
Posted: Sat Aug 29, 2020 2:25 am
Trying to understand how bit resolution translates to maximum observable dynamic range in the spectrum display.
I thought that, given no decimation or other "tricks", maximum dynamic range is 20*log(2^(# of bits)) dB. So for an 8 bit RTL SDR the maximum dynamic range should be 48 dB. Yet I'm seeing upwards of 70 dB in the attached. The spectrum amplitude scale is relatively linear - I checked it against my HP8640B. AGC is off.
What am I missing?
Bob NO6B
I thought that, given no decimation or other "tricks", maximum dynamic range is 20*log(2^(# of bits)) dB. So for an 8 bit RTL SDR the maximum dynamic range should be 48 dB. Yet I'm seeing upwards of 70 dB in the attached. The spectrum amplitude scale is relatively linear - I checked it against my HP8640B. AGC is off.
What am I missing?
Bob NO6B