Oscillations - Determining amplitude and frequency values

I am investigating the synchrony of multiple oscillations and I am struggling to identify the upper/lower frequencies relative to the half maximum.

Could anyone suggest a simple way to:

• Identify the peak amplitude of an oscillation in a frequency range.
• Calculate 50% of this peak amplitude.
• Identify upper and lower amplitude values at 50%.
• Determine the corresponding frequency of the upper and lower 50% values.

Any help would be greatly appreciated!

Answer 1

[Jakob B. Nielsen]

Take a look at the builtin fourier analysis which is just perfect for an application such as the one you describe.