Reg No:

R5913 Pages: 2

Name:

APJ ABDUL KALAM TECHNOLOGICAL UNIVERSITY

FIFTH SEMESTER B.TECH DEGREE EXAMINATION, DECEMBER 2018

Course Code: EC301
Course Name: DIGITAL SIGNAL PROCESSING

Max. Marks: 100 Duration: 3 Hours
PART A
Answer any two full questions, each carries 15 marks. Marks
1 a) Given x(n) = { 1, -2, 3, -4, 5, -6 } without calculating DFT find the following (5)
quantities?

a) ೫0) ൫൭.0) ० XB) AYIO! 9൭-10)
b) Find the convolution of x(n) = {1, 2, 3, 4, 5} and h(n) = {1, 1, 1} using overlap (5)

save method?

c) State Circular frequency shift property of DFT? (5)

4 0൧ DFT of the signal x(n) ={a, 0, ०, d} is X(K). Find the IDFT of X(K-2) ?

2 a) Find the number of complex multiplications and additions involved in the (4) calculation of

1024 DFT using direct computation and radix2 FFT algorithm?

b)

6

How will you obtain linear convolution from circular convolution? For x(n) (5) ={1, 2,
3} and h(n) = {-1, -2}, obtain linear convolution x(n)*h(n) using circular convolution?
Given at g(n) ={1, 0, 1, 0] and h(n) = {1, 2, 2, 1} find the 4 point DFTs of these (6)

sequences using a single 4 point DFT.

3 a) Describe the steps involved in radix 2 DIT FFT algorithm (5) b) Find the DFT of the
sequence {1, 2, 3, 4, 4, 3, 2, 1} using DIT algorithm (7)
c) What do you mean by in place computation of DFT? (3)
PART B
Answer any two full questions, each carries 15 marks.
4 8) Explain the significance of linear phase FIR filter and comment on its impulse (4)
response?

b) Design an ideal lowpass filter with frequency response (6)

() = 1 0 -0.5 < < and 0.5() = 0 0.5 <| |.

Find h(n) for N = 11.( use rectangular window )

c) Determine the frequency response of FIR filter defined by (5)

y(n) = 0.25x(n) + x(n - 1) + 0.25x(n - 2). Calculate the phase delay and group delay?

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