- 9th February 2009, 14:30 #1

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## What is importance of frequency domain analysis over time ?

Why signals are mostly studied in frequency domain?

- 9th February 2009, 14:30

- 9th February 2009, 16:30 #2
## What is importance of frequency domain analysis over time ?

I think, because if you know frequency response of the system, you can easily predict its response in time domain for any type of input signal. (And vice-versa as well). Another reason could be well known technique of determining system stability based on frequency response.

- 9th February 2009, 16:30

- 10th February 2009, 12:49 #3

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## What is importance of frequency domain analysis over time ?

can you be more clear.

- 10th February 2009, 12:49

- 10th February 2009, 19:16 #4
## Re: What is importance of frequency domain analysis over ti

Originally Posted by**nl5**

Every system has a transfer function in frequency domain: T(ω). Very often it is done not as a function of frequency ω (ω=2πf), but Laplace parameter s=jω: T(s).

If you apply signal f(t) to the system and want to know output g(t), there is a simple formula in frequency domain:

G(s) = T(s)*F(s),

where G(s) and F(s) are Laplace transforms of g(t) and f(t).

So, you have f(t), then found F(s), multiply by T(s), get G(s), performe inverse Laplace transform to obtain g(t).

Originally Posted by**nl5**

Thank you.

- 11th February 2009, 09:46 #5

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## What is importance of frequency domain analysis over time ?

we can see some poles n zeros of system easily to check abt system stability