What sets the minimum detectable signal level for a direct-sampling software defined receiver in the absence of atmospheric or thermal noise?
Sample clock phase noise
Reference voltage level and sample width in bits✓Correct answer
Data storage transfer rate
Missing codes and jitter
Explanation
The smallest step an analog-to-digital converter can resolve is its full-scale reference voltage divided by 2ⁿ for n bits. With no external noise present, that least-significant-bit size and the quantization noise that goes with it set the smallest signal the receiver can detect.