On 07/06/2011 21:05, RNGolding@aol.com wrote:
> So far so good, however the sine waves have some jitter so I thought I
> would take the average of a few consecutive phase measurements. That is  =
where
> I come unstuck, how do you average phase readings?
>
> To illustrate the problem, if the phase is jittering about zero  degrees
> giving 4 phase readings of say, 358, 359, 1 and  2 degrees, a simple aver=
age
> calculation yields 180 deg, which is  obviously wrong. Does anyone know h=
ow
> calculate the true average,  which  should be 0 degrees? I'm sure the ans=
wer
> is obvious, but it has defeated me so  far.

Not thought this through very carefully but...
What about not wrapping to 0 after 360? (i.e unwrapping the phase)
So you just keep going, and then after you average the readings you mod=20
by 360 to get the result.
So if you have 358, 359, 360, 361, 362. You get an average of 360, then=20
360 % 360 =3D 0
Or if 178,179,180,181,182 -> 180 % 360 =3D 180.
Or 720,721,722 -> 721 % 360 =3D 1


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