How is the phase angle on the fourier analysis calculated in Multisim?

[AnalogJoe]

Hi everyone, im wondering how is the phase angle on the fourier analysis calculated, I normally use the "cosine" version of the Fourier series as follows:

However im aware that theres also the "sine" version which goes as follows:

So for instance, for a particular waveform (a pulsed sawtooth) I calculated the phase of the first harmonic (by hand and paper) using the "cosine" formula and it turns out to be 237.52º . I simulated the same waveform on multisim and the phase angle calculated by multisim is -32.61º.

Now I thought multisim was just using the "sine" formula, but if im not mistaken the angle using the sine formula is simply the angle taken with the cosine formula minus 90º so: 237.52º-90=147.52º.

The only explanation I have is that multisim considers angles bigger than 180 as negative, thus an angle of 237.52º would be -122.48º represented as a negative angle, which when converted to the sine representation would be -122.48º+90º= -32.48º which is close enough to the value calculated by Multisim.

So any comments on how the phase angle should be considered in multisim?

[AnalogJoe]

Anyone?

[Omar_R]

Hello AnalogJoe

I just found the following white paper that describes how the Fourier Analysis works in Multisim. Hope you find this information useful. 

Cheers.