Sound & Vibration 3.1 Background knowledge

[Steve SO]

Hi All,

I am using the Sound & Vibration 3.1 to develop the program. I am interested in to get more background knowledge from the corresponding subvi. Hope that you can ask my questions. Thanks

Q1: sv_Swept Sine Apply Window (dual).vi

What is the purpose of the window data?? 

Why integration time index to be added by 1??

Why the ENBW must be 1.5?? (Is Standard??)

Q2: sv_Insert Swept Scaled Response Magnitude.vi

Why the Time (i.e. Integration time index - settle time index) need to be multipled by 2?

BTW, What is the algorithm for calculating the scaled response magnitude.

From my testing observation, i see that the scaled response magnitude is the peak voltage value.

Thanks&Regards,

Steve

[Now_With_Underscores]

Hi Steve,

The swept sine apply window subtracts the settling time from the integration time and then adds 1 (to account for the first sample, which is the last sample of the settling time).  This period is then converted to a frequency inversion, and then is multiplied by the input parameters.  Therefore, signals in the window range are passed and lower and higher frequencies are not.  Every window has a specific noise bandwidth; in this case the window is 1.5 (Hanning). 

I will need to get back to you on why we need to divide the stime index by 2.  

Have a great evening!