Download GTU B.Tech 2020 Winter 7th Sem 171003 Digital Signal Processing Question Paper

Download GTU (Gujarat Technological University Ahmedabad) B.Tech/BE (Bachelor of Technology/ Bachelor of Engineering) 2020 Winter 7th Sem 171003 Digital Signal Processing Previous Question Paper

Seat No.: ________
Enrolment No.___________
GUJARAT TECHNOLOGICAL UNIVERSITY
BE- SEMESTER?VII (OLD) EXAMINATION ? WINTER 2020
Subject Code:171003 Date:25/01/2021
Subject Name:Digital Signal Processing
Time:10:30 AM TO 12:30 PM Total Marks: 56
Instructions:
1. Attempt any FOUR questions out of EIGHT questions.

2. Make suitable assumptions wherever necessary.

3. Figures to the right indicate full marks.
Q.1
(a) Draw the block diagram of a typical discrete time system and explain in 07
brief. What are the advantages and disadvantages of digital signal
processing over analog signal processing ?

(b) Perform the linear convolution of the following two sequences:
07
x1(n) = 2(n)+ (n-1) - (n-2) + 2(n-3)
x2(n) = (n) - (n-1) + (n-2)
Q.2
(a) Enlist the properties of the z-transform? Prove the convolution property 07
of z-transform.

(b) Determine the z-transform of the following:
07
(i) x(n) = (-1/3)n u(n) - (-1/2)n u(-n-1)
(ii) x(n) = an , 0 n N-1
Q.3
(a) Determine the inverse z-transform of the following:
07
(i)X(z) = (1+z-1)2 / (1-(1/2)z-1)(1-z-1) , |z | >1
(ii)X(z)=log(1+az-1 ) , |z | > |a |

(b) Derive the expression of reconstruction of a bandlimited signal from its 07
samples.




Q.4
(a) A discrete time system is given below:
07
H(z) = (1+ z-1 )2 / (1- 0.75z-1 + 0.125z-2 )
Draw the following structures of the system:
(i)Direct-form-I (ii) Direct-form-II (iii)Cascade (iv)Parallel

(b) What is a linear phase system? Discuss different types of FIR linear 07
phase systems.
Q.5
(a) Discuss the basic structures implementing IIR discrete time systems.
07

(b) Explain the limit cycles in fixed point realizations of IIR digital filters. 07
What is the solution to avoid limit cycles ?




Q.6
(a) Discuss the discrete time IIR filter design by
07
(i)Impulse Invariance method (ii)Bilinear transformation

(b) Design an FIR low-pass filter satisfying the specification
07
0.98 < H(ejw) < 1.02. 0 |w|0.63
-0.15 < H(ejw) < 0.15. 0.65 |w|
By applying a Kaiser window to the impulse response hd[n] for the ideal
discrete time low-pass filter with cutoff wc=0.64. find the value of
and M required to satisfy this specification.
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Q.7
(a) Enlist the properties of the Discrete-Fourier transform? Prove the 07
frequency modulation property of Discrete-Fourier transform.

(b) Write a short note on Decimation-in-frequency FFT algorithm.
07




Q.8
(a) Perform the 4-point circular convolution of the following two sequences: 07
x(n) = (n)+ 2(n-1) + 3(n-2) + 4(n-3)
h(n) = (n)+ 2(n-1) + (n-2) + 2(n-3)

(b) Explain any two applications of Digital Signal Processing.
07
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