Download PTU (I.K.Gujral Punjab Technical University (IKGPTU)) B-Tech (Bachelor of Technology) (ECE)-Electronics And Communications Engineering 2020 December 4th Sem 77568 Signals And Systems Previous Question Paper
Roll No.
Total No. of Pages : 02
Total No. of Questions : 18
B.Tech. (Electronics & Communication Engineering) (2018 Batch)
(Sem.?4)
SIGNALS AND SYSTEMS
Subject Code : BTEC-403-18
M.Code : 77568
Time : 3 Hrs. Max. Marks : 60
INST RUCT IONS T O CANDIDAT ES :
1 .
SECT ION-A is COMPULSORY cons is ting of TEN questions carrying TWO marks
each.
2 .
SECT ION-B c ontains F IVE questions c arrying FIVE marks eac h and s tud ents
have to atte mpt any FOUR q ues tions.
3 .
SECT ION-C contains THREE questions carrying T EN marks e ach and s tudents
have to atte mpt any T WO questio ns.
SECTION-A
Write briefly :
Q1 What is time inversion property of signal?
Q2 What is Central Limit Theorem?
Q3 What is Ergodic Process?
Q4 Define Power Signal.
Q5 Write down Dirichlet's condition of Fourier series.
Q6 What do you mean by Stable System?
Q7 Differentiate between auto correlation and cross correlation function.
Q8 State the significance of difference equations.
Q9 What is the difference between recursive and non-recursive systems?
Q10 What do you mean by Forced Response?
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SECTION-B
Q11 State and prove sampling theorem for low pass signals.
Q12 Decompose the signal into even and odd parts:
a) 3t2 + 2t + 1
1,1,
1
b)
Q13 Define Z-transform. State and prove any three properties of Z-transform.
Q14 Prove that for BIBO stable discrete time LTI system, the ROC of the system function
includes unit circle.
Q15 State and prove Parseval's Theorem.
SECTION-C
Q16 An LTI system is described by following input-output relation :
y(n) ? 9/4 y(n?1) +1/2 y(n?2) = x(n)?3 x(n?1)
Determine the impulse response of the system with specified ROC's of H(Z) for the
conditions :
a) System is Stable.
b) System is Causal.
Q17 Find the CTFT of the signal x(t)= t e-at u(t) using appropriate property. State and prove the
properties used.
Q18 Show that spectrum of the sampled signal is the infinite sum of shifted replicas of the
spectrum of original signal.
NOTE : Disclosure of Identity by writing Mobile No. or Making of passing request on any
page of Answer Sheet will lead to UMC against the Student.
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This post was last modified on 13 February 2021