n-channel anaylsis

[celynn]

Hi, Anyone can advise me on how to create an n-channel anaylsis using cross-spectrum?

[TylerS]

celynn,

Are you wanting to do a cross spectrum of N signals with some other signal? If this is the case, you can put the cross spectrum VI in a for loop and iterate it for each signal, comparing to the other signal.

If you're wanting to do something like a cross spectrum analysis on more than 2 signals at a time against each other, I'm not sure if that makes sense mathematically. It would be like trying to convolve more than two signals at a time, which I'm not sure can be done. But I'm sure someone with more math expertise could offer help with that question.

I hope this helps, but give us a little more information on what exactly you want to do and someone should be able to help you. Have a great day!

Tyler S. 

[celynn]

Hi Taylor S,thanks for your reply.

Say i got 3 or more signals i want to find the cross spectrum of each of them with reference to each others.

ie signals x y z  i want to do a cross spectrum between xy xz  yz .

[TylerS]

celynn,

So you could do something as simple as 3 instances of either the Cross Spectrum (phase-mag).vi or the Cross Spectrum (real-imag).vi. Then wire the different combinations of signals as the X and Y inputs. Those VIs are located on the All Functions>>Analyze>>Waveform Measurements palette.

Does this answer your questions?

Tyler S