Digital Signal Processing
chantinh2004
Week4_assignment.docxAssignment 3: Discrete-time Fourier Transform
Note: You may use Matlab to solve the problems where necessary
All questions carry equal points
1. Find the DTFT of the sequence .
2. Determine the DTFT of x[n] = 2nαnu[n], with |α| < 1. Hint: use the differentiation rule in the time domain.
3. If , what is its DTFT?
4. Find the IDTFT of . Hint: use the differentiation rule in the frequency domain.
5. The transfer function of an LTI discrete-time system is given by . Calculate its response to an input using DTFT.
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