Explore topic-wise MCQs in Digital Signal Processing.

This section includes 25 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 value of inverse Z-transform of log(\(\frac{z}{z+1}\)) is _______________

A. (-1)n/n for n = 0; 0 otherwise
B. (-1)n/n
C. 0, for n = 0; (-1)n/n, otherwise
D. 0
Answer» D. 0
2.

Given the z-transform pair\(X[n] \leftrightarrow \frac{32}{z^2-16}\), |z|<4The z-transform of the signal y[n] = x[n+1] + x[n-1] is _________

A. \(\frac{(z+1)^2}{(z+1)^2-16} + \frac{(z-1)^2}{(z-1)^2-16}\)
B. \(\frac{z^2 (1+z)}{z^2-16}\)
C. \(\frac{z^2 (z-1)}{z^2-16}\)
D. \(\frac{(z+2)^2}{(z+2)^2-16}\)
Answer» C. \(\frac{z^2 (z-1)}{z^2-16}\)
3.

The value of \(Z^{-1}\Big\{\frac{z^2}{(z-a)(z-b)}\Big\}\) is ____________

A. \(\frac{a^{n+1} – b^{n+1}}{a+b}\)
B. }\Big\}\) is ____________a) \(\frac{a^{n+1} – b^{n+1}}{a+b}\) b) \(\frac{a^{n+1} – b^{n+1}}{a-b}\)
C. \(\frac{a^{n+1} + b^{n+1}}{a-b}\)
D. \(\frac{a^{n+1} + b^{n+1}}{a+b}\)
Answer» C. \(\frac{a^{n+1} + b^{n+1}}{a-b}\)
4.

The system described by the difference equation y(n) – 2y(n-1) + y(n-2) = X(n) – X(n-1) has y(n) = 0 and n<0. If x (n) = δ(n), then y (z) will be?

A. 2
B. 1
C. 0
D. -1
Answer» D. -1
5.

Given the z-transform pair 3nn2 u[n] ↔ X (z). The time signal corresponding to {X(z)}2 is ___________

A. {x[n]}2
B. x[n]*x[n]
C. x[n]*x[-n]
D. x[-n]*x[-n]
Answer» C. x[n]*x[-n]
6.

Given the z-transform pair 3nn2 u[n] ↔ X (z). The time signal corresponding to \(\frac{z^2-z^{-2}}{2}\) X(z) is ___________

A. \(\frac{1}{2}\)(x[n+2]-x[n-2])
B. (x[n+2]-x[n-2])
C. \(\frac{1}{2}\)(x[n-2]-x[n+2])
D. (x[n-2]-x[n+2])
Answer» B. (x[n+2]-x[n-2])
7.

Given the z-transform pair 3nn2 u[n] ↔ X (z). The time signal corresponding to \(\frac{dX(z)}{dz}\) is ___________

A. (n-1)33n-1u[n-1]
B. n33nu[n-1]
C. (1-n)33n-1u[n-1]
D. (n-1)33n-1u[n]
Answer» D. (n-1)33n-1u[n]
8.

Given the z-transform pair 3nn2 u[n] ↔ X (z). The time signal corresponding to X(z-1) is ___________

A. n23-nu[n]
B. n23-nu[-n]
C. \(\frac{1}{n^2} 3^{\frac{1}{n}} u[n]\)
D. \(\frac{1}{n^2} 3^{\frac{1}{n}} u[-n]\)
Answer» C. \(\frac{1}{n^2} 3^{\frac{1}{n}} u[n]\)
9.

What is the causal signal x(n) having the z-transform X(z)=\(\frac{1}{(1+z^{-1})(1-z^{-1})^2}\)?

A. [1/4(-1)n+3/4-n/2]u(n)
B. [1/4(-1)n+3/4-n/2]u(-n-1)
C. [1/4+3/4(-1)n-n/2]u(n)
D. [1/4(-1)n+3/4+n/2]u(n)
Answer» E.
10.

What is the inverse z-transform of X(z)=\(\frac{1}{1-1.5z^{-1}+0.5z^{-2}}\) if ROC is 0.5<|z|<1?

A. -2u(-n-1)+(0.5)nu(n)
B. -2u(-n-1)-(0.5)nu(n)
C. -2u(-n-1)+(0.5)nu(-n-1)
D. 2u(n)+(0.5)nu(-n-1)
Answer» C. -2u(-n-1)+(0.5)nu(-n-1)
11.

What is the inverse z-transform of X(z)=\(\frac{1}{1-1.5z^{-1}+0.5z^{-2}}\) if ROC is |z|<0.5?

A. [-2-0.5n]u(n)
B. [-2+0.5n]u(n)
C. [-2+0.5n]u(-n-1)
D. [-2-0.5n]u(-n-1)
Answer» D. [-2-0.5n]u(-n-1)
12.

What is the partial fraction expansion of the proper function X(z)=\(\frac{1}{1-1.5z^{-1}+0.5z^{-2}}\)?

A. \(\frac{2z}{z-1}-\frac{z}{z+0.5}\)
B. \(\frac{2z}{z-1}+\frac{z}{z-0.5}\)
C. \(\frac{2z}{z-1}+\frac{z}{z+0.5}\)
D. \(\frac{2z}{z-1}-\frac{z}{z-0.5}\)
Answer» E.
13.

What is the proper fraction and polynomial form of the improper rational transformX(z)=\(\frac{1+3z^{-1}+\frac{11}{6} z^{-2}+\frac{1}{3} z^{-3}}{1+\frac{5}{6} z^{-1}+\frac{1}{6} z^{-2}}\)?

A. 1+2z-1+\(\frac{\frac{1}{6}z^{-1}}{1+\frac{5}{6} z^{-1}+\frac{1}{6} z^{-2}}\)
B. 1-2z-1+\(\frac{\frac{1}{6} z^{-1}}{1+\frac{5}{6} z^{-1}+\frac{1}{6} z^{-2}}\)
C. 1+2z-1+\(\frac{\frac{1}{3} z^{-1}}{1+\frac{5}{6} z^{-1}+\frac{1}{6} z^{-2}}\)
D. 1+2z-1–\(\frac{\frac{1}{6} z^{-1}}{1+\frac{5}{6} z^{-1}+\frac{1}{6} z^{-2}}\)
Answer» B. 1-2z-1+\(\frac{\frac{1}{6} z^{-1}}{1+\frac{5}{6} z^{-1}+\frac{1}{6} z^{-2}}\)
14.

What is the inverse z-transform of X(z)=log(1+az-1) |z|>|a|?

A. x(n)=(-1)n+1 \(\frac{a^{-n}}{n}\), n≥1; x(n)=0, n≤0
B. x(n)=(-1)n-1 \(\frac{a^{-n}}{n}\), n≥1; x(n)=0, n≤0
C. x(n)=(-1)n+1 \(\frac{a^{-n}}{n}\), n≥1; x(n)=0, n≤0
D. None of the mentioned
Answer» D. None of the mentioned
15.

What is the inverse z-transform of X(z)=\(\frac{1}{1-1.5z^{-1}+0.5z^{-2}}\) if ROC is |z| < 0.5?

A. {….62,30,14,6,2}
B. {…..62,30,14,6,2,0,0}
C. {0,0,2,6,14,30,62…..}
D. {2,6,14,30,62…..}
Answer» C. {0,0,2,6,14,30,62…..}
16.

What is the inverse z-transform of X(z)=\(\frac{1}{1-1.5z^{-1}+0.5z^{-2}}\) if ROC is |z|>1?

A. {1,3/2,7/4,15/8,31/16,….}
B. {1,2/3,4/7,8/15,16/31,….}
C. {1/2,3/4,7/8,15/16,31/32,….}
D. None of the mentioned
Answer» B. {1,2/3,4/7,8/15,16/31,….}
17.

WHAT_IS_THE_INVERSE_Z-TRANSFORM_OF_X(Z)=_1/(1-1.5Z-1+0.5Z2-2_)_IF_ROC_IS_|Z|>1??$

A. (2-0.5<sup>n</sup>)u(n)
B. (2+0.5<sup>n</sup>)u(n)
C. (2<sup>n</sup>-0.5<sup>n</sup>)u(n)
D. None of the mentioned
Answer» B. (2+0.5<sup>n</sup>)u(n)
18.

What_is_the_inverse_z-transform_of_X(z)=_1/(1-1.5z-1+0.5z-2_)_if_ROC_is_|z|<0.5? a)_[-2-0.5n]u(n)$

A. [-2+0.5<sup>n</sup>]u(n)
B. [-2+0.5<sup>n</sup>]u(-n-1)
C. [-2-0.5<sup>n</sup>]u(-n-1)
Answer» D.
19.

What_is_the_causal_signal_x(n)_having_the_z-transform_X(z)=_1/((1+z-1_)_[(1-z-1)]2_)?

A. [1/4(-1)<sup>n</sup>+3/4-n/2]u(n)
B. [1/4(-1)<sup>n</sup>+3/4-n/2]u(-n-1)
C. [1/4+3/4(-1)<sup>n</sup>-n/2]u(n)
D. [1/4(-1)<sup>n</sup>+3/4+n/2]u(n)
Answer» E.
20.

What is the partial fraction expansion of X(z)=1/((1+z-1 )(1-z-1)2)?

A. z/(4(z+1)) + 3z/(4(z-1)) + z/(2„Äñ(z+1)„Äó<sup>2</sup> )
B. z/(4(z+1)) + 3z/(4(z-1)) – z/(2〖(z+1)〗<sup>2</sup> )
C. z/(4(z+1)) + 3z/(4(z-1)) + z/(2„Äñ(z-1)„Äó<sup>2</sup> )
D. z/(4(z+1)) + z/(4(z-1)) + z/(2„Äñ(z+1)„Äó<sup>2</sup> )
Answer» D. z/(4(z+1)) + z/(4(z-1)) + z/(2‚Äö√Ñ√ª‚àö√ë‚àö¬±(z+1)‚Äö√Ñ√ª‚àö√ë‚àö‚â•<sup>2</sup> )
21.

What is the partial fraction expansion of X(z)= (1+z-1)/(1-z-1+0.5z-2 )?

A. (z(0.5-1.5j))/(z-0.5-0.5j) – (z(0.5+1.5j))/(z-0.5+0.5j)
B. (z(0.5-1.5j))/(z-0.5-0.5j) + (z(0.5+1.5j))/(z-0.5+0.5j)
C. (z(0.5+1.5j))/(z-0.5-0.5j) – (z(0.5-1.5j))/(z-0.5+0.5j)
D. (z(0.5+1.5j))/(z-0.5-0.5j) + (z(0.5-1.5j))/(z-0.5+0.5j)
Answer» C. (z(0.5+1.5j))/(z-0.5-0.5j) ‚Äö√Ñ√∂‚àö√ë‚àö¬® (z(0.5-1.5j))/(z-0.5+0.5j)
22.

What is the partial fraction expansion of the proper function X(z)= 1/(1-1.5z-1+0.5z-2 )?

A. 2z/(z-1)-z/(z+0.5)
B. 2z/(z-1)+z/(z-0.5)
C. 2z/(z-1)+z/(z+0.5)
D. 2z/(z-1)-z/(z-0.5)
Answer» E.
23.

What is the proper fraction and polynomial form of the improper rational transform

A. = (1+3z<sup>-1</sup>+11/6 z<sup>-2</sup>+1/3 z<sup>-3</sup>)/(1+5/6 z<sup>-1</sup>+1/6 z<sup>-2</sup> )?
B. 1+2z -1+(1/6 z<sup>-1</sup>)/(1+5/6 z<sup>-1</sup>+1/6 z<sup>-2</sup> )
C. 1-2z -1+(1/6 z<sup>-1</sup>)/(1+5/6 z<sup>-1</sup>+1/6 z<sup>-2</sup> )
D. 1+2z -1+(1/3 z<sup>-1</sup>)/(1+5/6 z<sup>-1</sup>+1/6 z<sup>-2</sup>)
Answer» B. 1+2z -1+(1/6 z<sup>-1</sup>)/(1+5/6 z<sup>-1</sup>+1/6 z<sup>-2</sup> )
24.

What is the inverse z-transform of X(z)=1/(1-1.5z-1+0.5z-2 ) if ROC is |z|>1?

A. {1,3/2,7/4,15/8,31/16,….}
B. {1,2/3,4/7,8/15,16/31,….}
C. {1/2,3/4,7/8,15/16,31/32,….}
D. None of the mentioned
Answer» B. {1,2/3,4/7,8/15,16/31,‚Äö√Ñ√∂‚àö√묨‚àÇ.}
25.

Which of the following method is used to find the inverse z-transform of a signal?

A. Counter integration
B. Expansion into a series of terms
C. Partial fraction expansion
D. All of the mentioned
Answer» E.