why we are using impulse signal for analysis of any control system?
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| Impulse signal spectrum |
"In signal processing, the impulse response, or impulse response function, of a dynamic system is its output when presented with a brief input signal, called an impulse".
The reason why we use impulse responce for analysis of any control system is because any signal can be represented using impulse responce.
Example,
If i wants to sample a signal & if i wantprecise samples then i need to use impulse signal as a sampling signal although its not possible to generate animpulse signal because width of that signal approches to zero at origin.