iVenky wrote on Dec 18th, 2018, 3:58pm:
What's that that's causing the measurement error to change? if you look at the figure below, we can see that the noise power changes by about 10 dB (between -50 dBm and -60 dBm). Why does this happen?
Noise.iVenky wrote on Dec 18th, 2018, 3:58pm:
Which one is accurate or right?
Averaging the power - i.e. normal averaging - is equivalent of making multiple measurements (N), which in general reduces your noise (by 1/N). I believe reducing the resolution bandwidth would have a similar effect. Narrower bandwidth means longer integration, which is just kind of an extreme version of averaging.
Averaging the log would give you a nicer curve, with less noise. It would make sense to me, if there would be an exponential characteristic somewhere in the processing chain.
If you have a strong enough signal, than it does not matter which one you choose.