Explore topic-wise MCQs in Digital Signal Processing.

This section includes 16 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.

If x(n) is the input signal of a system with impulse response h(n) and y(n) is the output signal, then the auto correlation of the signal y(n) is?

A. rxx(l)*rhh(l)
B. rhh(l)*rxx(l)
C. rxy(l)*rhh(l)
D. ryx(l)*rhh(l)
Answer» C. rxy(l)*rhh(l)
2.

What is the auto correlation of the sequence x(n)=anu(n), 0

A. \(\frac{1}{1-a^2}\) al (l≥0)
B. \(\frac{1}{1-a^2}\) a-l (l<0)
C. \(\frac{1}{1-a^2}\) a|l|(-∞<l<∞)
D. All of the mentioned
Answer» E.
3.

Auto correlation sequence is an even function.

A. True
B. False
Answer» B. False
4.

The normalized auto correlation ρxx(l) is defined as _____________

A. \(\frac{r_{xx}(l)}{r_{xx}(0)}\)
B. –\(\frac{r_{xx}(l)}{r_{xx}(0)}\)
C. \(\frac{r_{xx}(l)}{r_{xy}(0)}\)
D. None of the mentioned
Answer» B. –\(\frac{r_{xx}(l)}{r_{xx}(0)}\)
5.

What is the cross correlation sequence of the following sequences?x(n)={….0,0,2,-1,3,7,1,2,-3,0,0….}y(n)={….0,0,1,-1,2,-2,4,1,-2,5,0,0….}

A. {10,9,19,36,-14,33,0,7,13,-18,16,7,5,-3}
B. {10,-9,19,36,-14,33,0,7,13,-18,16,-7,5,-3}
C. {10,9,19,36,14,33,0,-7,13,-18,16,-7,5,-3}
D. {10,-9,19,36,-14,33,0,-7,13,18,16,7,5,-3}
Answer» C. {10,9,19,36,14,33,0,-7,13,-18,16,-7,5,-3}
6.

The cross correlation of two real finite energy sequences x(n) and y(n) is given as __________

A. \(r_{xy}(l)=\sum_{n=-\infty}^{\infty}x(n)y(n-l)\) where l=0,±1,±2,…
B. \(r_{xy}(l)=\sum_{n=0}^{\infty}x(n)y(n-l)\) where l=0,±1,±2,…
C. \(r_{xy}(l)=\sum_{n=-\infty}^{\infty}x(n)y(n-l)\) where -∞<l<∞
D. none of the mentioned
Answer» B. \(r_{xy}(l)=\sum_{n=0}^{\infty}x(n)y(n-l)\) where l=0,±1,±2,…
7.

AUTO_CORRELATION_SEQUENCE_IS_AN_EVEN_FUNCTION.?$

A. True
B. False
Answer» B. False
8.

What_is_the_auto_correlation_of_the_sequence_x(n)=anu(n),_0

A. 1/(1-a<sup>2</sup> )a<sup>l</sup> (l≥0)
B. 1/(1-a<sup>2</sup> )a<sup>-l</sup> (l<0)
C. 1/(1-a<sup>2</sup> )a<sup>|l|</sup>(-‚àû<l<‚àû)
D. All of the mentioned
Answer» E.
9.

If_x(n)_is_the_input_signal_of_a_system_with_impulse_response_h(n)_and_y(n)_is_the_output_signal,_then_the_auto_correlation_of_the_signal_y(n)_is:

A. r<sub>xx</sub>(l)*r<sub>hh</sub>(l)
B. r<sub>hh</sub>(l)*r<sub>xx</sub>(l)
C. r<sub>xy</sub>(l)*r<sub>hh</sub>(l)
D. r<sub>yx</sub>(l)*r<sub>hh</sub>(l)
Answer» C. r<sub>xy</sub>(l)*r<sub>hh</sub>(l)
10.

The normalized auto correlation ρxx(l) is defined as?#

A. (r<sub>xx</sub> (l))/(r<sub>xx</sub> (0))
B. -(r<sub>xx</sub> (l))/(r<sub>xx</sub> (0))
C. (r<sub>xx</sub> (l))/(r<sub>xy</sub> (0))
D. None of the mentioned
Answer» B. -(r<sub>xx</sub> (l))/(r<sub>xx</sub> (0))
11.

What is the relation between cross correlation and auto correlation?

A. |r<sub>xy</sub>(l)|=‚àö(r<sub>xx</sub>(0).r<sub>yy</sub>(0))
B. |r<sub>xy</sub>(l)|‚â•‚àö(r<sub>xx(0)</sub>.r<sub>yy</sub>(0))
C. |r<sub>xy</sub>(l)|≠√(r<sub>xx(0)</sub>.r<sub>yy</sub>(0))
D. |r<sub>xy</sub>(l)|‚â§‚àö(r<sub>xx(0)</sub>.r<sub>yy</sub>(0))
Answer» E.
12.

What is the energy sequence of the signal ax(n)+by(n-l) in terms of cross correlation and auto correlation sequences?

A. a<sup>2</sup>r<sub>xx</sub>(0)+b<sup>2</sup>r<sub>yy</sub>(0)+2abr<sub>xy</sub>(0)
B. a<sup>2</sup>r<sub>xx</sub>(0)+b<sup>2</sup>r<sub>yy</sub>(0)-2abr<sub>xy</sub>(0)
C. a<sup>2</sup>r<sub>xx</sub>(0)+b<sup>2</sup>r<sub>yy</sub>(0)+2abr<sub>xy</sub>(1)
D. a<sup>2</sup>r<sub>xx</sub>(0)+b<sup>2</sup>r<sub>yy</sub>(0)-2abr<sub>xy</sub>(1)
Answer» D. a<sup>2</sup>r<sub>xx</sub>(0)+b<sup>2</sup>r<sub>yy</sub>(0)-2abr<sub>xy</sub>(1)
13.

Which of the following is the auto correlation of x(n)?

A. r<sub>xy</sub>(l)=x(l)*x(-l)
B. r<sub>xy</sub>(l)=x(l)*x(l)
C. r<sub>xy</sub>(l)=x(l)+x(-l)
D. None of the mentioned
Answer» B. r<sub>xy</sub>(l)=x(l)*x(l)
14.

What is the cross correlation sequence of the following sequences?

A. ={….0,0,2,-1,3,7,<strong>1</strong>,2,-3,0,0….}
B. ={….0,0,1,-1,2,-2,<strong>4</strong>,1,-2,5,0,0….}
C. {10,9,19,36,-14,33,0,<strong>7</strong>,13,-18,16,7,5,-3}
D. {10,-9,19,36,-14,33,0,<strong>7</strong>,13,-18,16,-7,5,-3}
Answer» C. {10,9,19,36,-14,33,0,<strong>7</strong>,13,-18,16,7,5,-3}
15.

Which of the following relation is true?

A. r<sub>xy</sub>(l)= r<sub>xy</sub>(-l)
B. r<sub>xy</sub>(l)= r<sub>yx</sub>(l)
C. r<sub>xy</sub>(l)= r<sub>yx</sub>(-l)
D. None of the mentioned
Answer» D. None of the mentioned
16.

Which of the following parameters are required to calculate the correlation between the signals x(n) and y(n)?

A. Time delay
B. Attenuation factor
C. Noise signal
D. All of the mentioned
Answer» E.