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sddsnaff at fixed frequency

Posted: 09 Oct 2015, 09:14
by wguo
Hi Michael,

Is it possible to add one input for sddsnaff such that it analyzes data at the input frequency?
The problem arises when I apply naff to the turn-by-turn data of all the BPMs in the ring. In principle the main frequency should be the same for different BPMs; however, a small spread comes out and results in a large phase deviation when the number of turns becomes large.

Weiming

Re: sddsnaff at fixed frequency

Posted: 23 Oct 2015, 08:51
by michael_borland
Weiming,

Is the ideal to process N signals together and force the use of the same frequency for all of them?

--Michael

Re: sddsnaff at fixed frequency

Posted: 23 Oct 2015, 10:08
by wguo
Yes. Sddsnaff gives slightly different frequencies for N signals. It is critical if the phase is a concern.
I could do a simple FFT myself since the frequency is given, however, I trust sddsnaff to be more reliable in case there is only a small number of turns.

Weiming