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Hi

you should perhaps say a little more about your need, if it's for a time analysis I understand a tone burst as a modulated sine wave function of the type a(t)*sin(2*pi*freq*t) where freq is a parameter and t the time. So long a(t) is not too steep and continuously derivable I suppose it's OK for the solver.

But you have also the harmonic development approach and get the frequency scan of the harmonic response of your system, it depends what you want to do

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Good luck
Ivar

hello Ivar and Thanks for your reply,

I need the toneburst or rectangualr signal for transinet analysis and I do not know how to define this exitation signal at the front edge of a simulated transducer?

Hello,

I want to simulate Toneburst signal using equation: Volts*sin(2*pi*frequency*t)*(t<duration)

Do I need any other parameters?

I am new on COMSOL so I would be grateful if some one explains me all the steps starting from building geometry to running model.

Thank you very much

an1(t)=exp(-((t-mu)^2/(2*(std^2))))*sin(2*pi*f*t)
Where t is time, f is frequency and std and mu are the parameters which decides the number of peaks. For example:
f = 50000
mu = 6.5e-5
std = 2e-5

Often one wants a toneburst that is "smooth" so that the Fourier spectrum is not too broad. A rectangular window will give Fourier components at a wide range of frequencies. There is a huge variety of smooth window functions with different properties.

My personal favorite is A*sin(2*pi*f*t)*sin(pi*f*t/n)*(t<n/f). Mostly for reasons of simplicity.

DWGreve
DWGreve Consulting