Undersampling ADC for RMS conversion possible?

Status
Not open for further replies.

nkmonty

Newbie level 1
Joined
Nov 20, 2019
Messages
1
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
14
Hello, I wanted to get opinions of the community on this topic:
Suppose you have ADC with sampling frequency Fs and all you are interested in in calculating RMS value of the input AC signal using digitized data.
If the AC signals contains harmonics above Fs/2 (Nyquist freq), you'll get fold back frequency components (aliasing) into Nyquist zone due to under sampling. But since you are not trying to recreate the original waveform, and just computing RMSm will your RMS computation still be correct (since you basically transforming higher frequency sine harmonics to lower frequency with the same amplitude due to aliasing)?
 

Hi,

Yes, undersampling is possible. But avoid fs to be integer division of f_AC.

Klaus
 
Status
Not open for further replies.

Similar threads

Cookies are required to use this site. You must accept them to continue using the site. Learn more…