A 06000EC301122001 Pages: 3
Reg No.: Name:
APJ ABDUL KALAM TECHNOLOGICAL UNIVERSITY
Fifth Semester B.Tech Degree Regular and Supplementary Examination December 2020
Course Code: EC301
Course Name: DIGITAL SIGNAL PROCESSING
Max. Marks: 100 Duration: 3 Hours
PARTA
Answer any two full questions, each carries 15 marks. Marks

1 a) Comment on the relationship between DTFT and DFT. (3)

b) Obtain the real sequence x(n) using DIT- IFFT algorithm if the first five points in (12)
the 8 point DFT of x(n) are given by {1.5, 0, 2+0.5j, 0, 0.5}

2 a) Given two real sequences x(n)=[1 2 3 1] and y(n)=[2 1 2 1]. Compute the DFTs (7)
X(k) and Y(k) of these two sequences using a single DFT calculation.

b) Given two sequences x[n] and y[n] such that x[n]=[2 2 0 2] and the 4 point (8)
circular convolution between x[n] and y[n] results in g[n]=[10 10 8 8] .
Determine the sequence y[n].

3 a) Using overlap save method and 5 point circular convolutions, determine the (9)
response of an LTI system with impulse response h(n) = u(n) + 260% — 1) -
u(n — 3) for an input sequence x(n) = 315൦ 406 (n — ¢), where
A, = 1, for k even
= 2, for k odd.
b) Given the eight point DFT X(k) of a sequence x(n) as (6)
೫॥)ಎ(1 25) 1 -1 2+2j -1- 1 2-j}.
Determine the following without directly computing the IDFT.
നാനി
0) x(4)
PART छ
Answer any two full questions, each carries 15 marks.
4 a) Design a low pass Butterworth digital filter using bilinear transformation for the (10)

given specifications

PB region: 0 - 400Hz

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