Digital Signal Processing Mid - I, September - 2014

1.An LTI Discrete time system is causal if and only if
• h(n)≠0 for n<0
• h(n)=0 for n<0
• h(n)≠ for n<0
• h(n)≠0 for n>0
2.For Energy signals, the energy will be finite and the average power will be _______
• Infinite
• finite
• zero
• can not be defined
3.Identify the dynamic system
• y(n) = ax2(n)
• y(n) = ax(n)
• y(n) = ax2(n) + x(n)
• y(n) = x(n)+x(n-1)
• N1 – N2 +1
• N1 + N2 –1
• N1 + N2 +1
• 2N1 – N2 +1
• N≠L
• N≤L
• N≥L
• N=L
• 64 & 80
• 80 & 64
• 24 & 12
• 64 & 32
• e-j2πN
• e-j2π/N
• e-j2π
• e-j2πNK
8.The Z-Transform is a
• Finite series
• Infinite power series
• Geometric series
• Both a & c
9.The ROC of the signal x(n) = an for -5 < n < 5 is
• Entire Z-plane
• Entire z-Plane expect Z = 0 and Z = • Entire Z-plane expect z = 0
• Entire Z-plane expect z = 10.Find the convolutions of the two signals x(n) = { 3, 2,1, 2} h(n) = {1, 2, 1, 2} is
• y(n)={3,8,8,12,9,4,4}
• y(n)={3,8,8,12,4,4,2}
• y(n)={3,8,12,9,4,4}
• y(n)={3,8,8,1,1,4,4}
14.If DFT of x(n) is X(K) then DFT ( Img x(n) ) is _______________
Answer: 