System identification from frequency response

1. How do you find the frequency response of a system?
2. What is the frequency response of a system?
3. What is the use of frequency response analysis?

How do you find the frequency response of a system?

First we substitute s = jω into H(s) to obtain an expression of the frequency response. Note that the numerator and the denomator are both complex. To obtain the amplitude response, we take the absolute value of H(jω). To do this, we evaluate the magnitude of the numerator and the denominator separately.

What is the frequency response of a system?

A frequency response describes the steady-state response of a system to sinusoidal inputs of varying frequencies and lets control engineers analyze and design control systems in the frequency domain.

What is the use of frequency response analysis?

A frequency response analysis is performed to determine the steady state vibration for a range of frequencies, one at a time. It can be used for structures which operate continuously at a single speed or those which change speed slowly enough so that steady state is maintained.