Explore topic-wise MCQs in Digital Signal Processing.

This section includes 23 Mcqs, each offering curated multiple-choice questions to sharpen your Digital Signal Processing knowledge and support exam preparation. Choose a topic below to get started.

1.

The ROC of z-transform of any signal cannot contain poles.

A. True
B. False
Answer» B. False
2.

A linear time invariant system is characterized by the system function H(z)=1/(1-0.5z-1 )+2/(1-3z-1 ).What is the ROC of H(z) if the system is causal?

A. |z|<3
B. |z|>3
C. |z|<0.5
D. |z|>0.5
Answer» C. |z|<0.5
3.

Is the discrete time LTI system with impulse response h(n)=an(n) (|a| < 1) BIBO stable?

A. True
B. False
Answer» B. False
4.

If all the poles of H(z) are inside the unit circle, then the system is said to be:

A. Only causal
B. Only BIBO stable
C. BIBO stable and causal
D. None of the mentioned
Answer» D. None of the mentioned
5.

The z-transform X(z) of the signal x(n)=anu(n) has:

A. One pole at z=0 and one zero at z=a
B. One pole at z=0 and one zero at z=0
C. One pole at z=a and one zero at z=a
D. One pole at z=a and one zero at z=0
Answer» E.
6.

What is the one sided z-transform X+(z) of the signal x(n)={1,2,5,7,0,1}?

A. z2+2z+5+7z-1+z-3
B. 5+7z+z3
C. z-2+2z-1+5+7z+z3
D. 5+7z-1+z-3
Answer» E.
7.

If pk, k=1,2,…N are the poles of the system and |pk| < 1 for all k, then the natural response of such a system is called as Transient response.

A. True
B. False
Answer» B. False
8.

What is the unit step response of the system described by the difference equationy(n)=0.9y(n-1)-0.81y(n-2)+x(n) under the initial conditions y(-1)=y(-2)=0?

A. [1.099+1.088(0.9)n.cos(πn/3+5.2o)]u(n)
B. [1.099+1.088(0.9)n.cos(πn/3-5.2o)]u(n)
C. [1.099+1.088(0.9)n.cos(πn/3-5.2o)].
D. None of the mentioned
Answer» C. [1.099+1.088(0.9)n.cos(πn/3-5.2o)].
9.

A linear time invariant system is characterized by the system function H(z)=1/(1-0.5z-1 )+2/(1-3z-1 ).What is the h(n) if the system is anti causal?

A. (0.5)nu(n)+2(3)nu(n)
B. (0.5)nu(-n-1)-2(3)nu(-n-1)
C. -[(0.5)n+2(3)n]u(-n-1)
D. (0.5)nu(n)-2(3)nu(-n-1)
Answer» D. (0.5)nu(n)-2(3)nu(-n-1)
10.

Sampling rate conversion by the rational factor I/D is accomplished by what connection of interpolator and decimator?

A. Parallel
B. Cascade
C. Convolution
D. None of the mentioned
Answer» C. Convolution
11.

What is the z-transform of the signal x(n)=[3(2n)-4(3n)]u(n)?

A. 3/(1-2z-1)-4/(1-3z-1)
B. 3/(1+2z-1)-4/(1+3z-1)
C. 3/(1-2z)-4/(1-3z)
D. None of the mentioned
Answer» B. 3/(1+2z-1)-4/(1+3z-1)
12.

The Nth root of unity WN is given as:

A. ej2πN
B. e-j2πN
C. e-j2π/N
D. ej2π/N
Answer» D. ej2π/N
13.

What are the values of z for which the value of X(z)=∞?

A. Poles
B. Zeros
C. Solutions
D. None of the mentioned
Answer» B. Zeros
14.

A linear time invariant system is characterized by the system function H(z)=1/(1-0.5z-1 )+2/(1-3z-1 ).What is the h(n) if the system is stable?

A. (0.5)nu(n)-2(3)nu(n)
B. (0.5)nu(-n-1)-2(3)nu(-n-1)
C. (0.5)nu(-n-1)-2(3)nu(n)
D. (0.5)nu(n)-2(3)nu(-n-1)
Answer» E.
15.

What is the one sided z-transform of x(n)=δ(n-k)?

A. z-k
B. zk
C. 0
D. 1
Answer» B. zk
16.

Which of the following justifies the linearity property of z-transform?[x(n)↔X(z)].

A. x(n)+y(n) ↔X(z)Y(z)
B. x(n)+y(n) ↔X(z)+Y(z)
C. x(n)y(n) ↔X(z)+Y(z)
D. x(n)y(n) ↔X(z)Y(z)
Answer» C. x(n)y(n) ↔X(z)+Y(z)
17.

What is the transient response of the system described by the difference equation y(n)=0.5y(n-1)+x(n) when the input signal is x(n)= 10cos(πn/4)u(n) and the system is initially at rest?

A. (0.5)nu(n)
B. 0.5(6.3)nu(n)
C. 6.3(0.5)n
D. 6.3(0.5)nu(n)
Answer» E.
18.

What is the ROC of the system function H(z) if the discrete time LTI system is BIBO stable?

A. Entire z-plane, except at z=0
B. Entire z-plane, except at z=∞
C. Contain unit circle
D. None of the mentioned
Answer» D. None of the mentioned
19.

A linear time invariant system is said to be BIBO stable if and only if the ROC of the system function:

A. Includes unit circle
B. Excludes unit circle
C. Is an unit circle
D. None of the mentioned
Answer» B. Excludes unit circle
20.

If the ROC of the system function is the exterior of a circle of radius r < ∞, including the point z = ∞, then the system is said to be:

A. Stable
B. Causal
C. Anti causal
D. None of the mentioned
Answer» C. Anti causal
21.

What is the steady-state response of the system described by the difference equation y(n)=0.5y(n-1)+x(n) when the input signal is x(n)= 10cos(πn/4)u(n) and the system is initially at rest?

A. 13.56cos(πn/4 -28.7o)
B. 13.56cos(πn/4 +28.7o)u(n)
C. 13.56cos(πn/4 -28.7o)u(n)
D. None of the mentioned
Answer» D. None of the mentioned
22.

What is the one sided z-transform of x(n)=δ(n+k)?

A. z-k
B. 0
C. zk
D. 1
Answer» C. zk
23.

Which of the following has to be performed in sampling rate conversion by rational factor?

A. Interpolation
B. Decimation
C. Either interpolation or decimation
D. None of the mentioned
Answer» B. Decimation