Output of transfer function given impulse response and input the

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SUMMARY

The discussion focuses on finding the output of a transfer function given an impulse response and input using Laplace transforms. The key steps involve taking the Laplace transforms of x(t) and h(t), multiplying them to obtain Y(s), and then finding the inverse Laplace transform to derive y(t). A significant point raised is the distinction between the one-sided Laplace transform, which assumes x(t) = 0 for t < 0, and the two-sided Laplace transform, which is less commonly used. The convolution integral method is emphasized as the preferred approach over the Fourier transform for this analysis.

PREREQUISITES
  • Understanding of Laplace transforms, specifically one-sided and two-sided Laplace transforms.
  • Familiarity with convolution integrals in signal processing.
  • Knowledge of Fourier transforms and their applications.
  • Basic principles of control systems and transfer functions.
NEXT STEPS
  • Study the properties and applications of the two-sided Laplace transform.
  • Learn about convolution integrals and their significance in signal processing.
  • Explore the differences between one-sided and two-sided Laplace transforms in detail.
  • Investigate the role of Fourier transforms in control systems and signal analysis.
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Students and professionals in electrical engineering, control systems engineers, and anyone involved in signal processing who seeks to deepen their understanding of transfer functions and impulse responses.

jaus tail
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Homework Statement


upload_2018-2-9_10-5-47.png


Homework Equations


Find laplace of x(t) and h(t)
Multiply the laplaced values to get Y(s)
Find inverse laplace to get y(t)

The Attempt at a Solution


upload_2018-2-9_10-17-34.png

In book the circled term isn't there. Why does that go away?
Book gets y(t) as
upload_2018-2-9_10-8-58.png

In laplace why does the e5t term go away?
 

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You will fin that the answer derives from the convolution integral. That method is valid for all time -∞ < t < ∞. The Laplace transform you're familiar with is most likely the one-sided Laplace transform which assumes x(t) = 0 for t < 0, so not applicable here.

There are two other alternatives: the Fourier transform and the two-sided Laplace transform. The latter is seldom encountered (see footnote) while the Fourier is appropriate and gives the same answer.

[Footnote: Then Brooklyn Poly's Professor John G. Truxal's venerable "Automatic Feedback Control System Synthesis" invokes it in preference to the Fourier].
 
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Thanks. Convolution is better than the Fourier route.
 

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