Signals and Systems: Unit V: Linear Time Invariant-Discrete Systems,,

Discrete Time Fourier Transform Analysis of DT Systems

Discuss about Discrete Time Fourier Transform Analysis of DT Systems and Solved Problem

5.4 DISCRETE TIME FOURIER TRANSFORM ANALYSIS OF DT SYSTEMS

Magnitude / Phase transfer functions using fourier transform.

Output of LTI system is given by

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Let us consider the LTI system is excited by sinusoidal signal.

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H(ω) is the fourier transform of h(k). H(ω) is called transfer function of the system.

H(ω) in polar form is |H(ω)| e j < H(ω)

|H(ω)| Magnitude of H(ω)

< H(ω) Angle of H(w)

Problem 1:

Write a difference equation that characterizes a system whose frequency response is

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Solution:

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Time shifting property of DTFT states that

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Taking inverse DTFT of above equation and applying time shifting property.

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Signals and Systems: Unit V: Linear Time Invariant-Discrete Systems,, : Tag: : - Discrete Time Fourier Transform Analysis of DT Systems