Explore topic-wise MCQs in Digital Signal Processing.

This section includes 13 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 we store the signal row wise and compute the L point DFT at each column, the resulting array must be multiplied by which of the following factors?

A. WNlq
B. WNpq
C. WNlq
D. WNpm
Answer» E.
Discussion
2.

If we store the signal row wise then the result must be read column wise.

A. True
B. False
Answer» B. False
Discussion
3.

Which is the correct order of the following steps to be done in one of the algorithm of divide and conquer method?i) Store the signal column wiseii) Compute the M-point DFT of each rowiii) Multiply the resulting array by the phase factors WNlq.iv) Compute the L-point DFT of each column.v) Read the result array row wise.

A. i-ii-iv-iii-v
B. i-iii-ii-iv-v
C. i-ii-iii-iv-v
D. i-iv-iii-ii-v
Answer» D. i-iv-iii-ii-v
Discussion
4.

How many complex additions are performed in computing the N-point DFT of a sequence using divide-and-conquer method if N=LM?

A. N(L+M+2)
B. N(L+M-2)
C. N(L+M-1)
D. N(L+M+1)
Answer» C. N(L+M-1)
Discussion
5.

How many complex multiplications are performed in computing the N-point DFT of a sequence using divide-and-conquer method if N=LM?

A. N(L+M+2)
B. N(L+M-2)
C. N(L+M-1)
D. N(L+M+1)
Answer» E.
Discussion
6.

If N=LM, then what is the value of WNmqL?

A. WMmq
B. WLmq
C. WNmq
D. None of the mentioned
Answer» B. WLmq
Discussion
7.

If the arrangement is of the form in which the first row consists of the first M elements of x(n), the second row consists of the next M elements of x(n), and so on, then which of the following mapping represents the above arrangement?

A. n=l+mL
B. n=Ml+m
C. n=ML+l
D. none of the mentioned
Answer» C. n=ML+l
Discussion
8.

Divide-and-conquer approach is based on the decomposition of an N-point DFT into successively smaller DFTs. This basic approach leads to FFT algorithms.

A. True
B. False
Answer» B. False
Discussion
9.

The computation of XR(k) for a complex valued x(n) of N points requires _____________

A. 2N2 evaluations of trigonometric functions
B. 4N2 real multiplications
C. 4N(N-1) real additions
D. All of the mentioned
Answer» E.
Discussion
10.

What is the real part of the N point DFT XR(k) of a complex valued sequence x(n)?

A. \(\sum_{n=0}^{N-1} [x_R (n) cos⁡\frac{2πkn}{N} – x_I (n) sin⁡\frac{2πkn}{N}]\)
B. \(\sum_{n=0}^{N-1} [x_R (n) sin⁡\frac{2πkn}{N} + x_I (n) cos⁡\frac{2πkn}{N}]\)
C. \(\sum_{n=0}^{N-1} [x_R (n) cos⁡\frac{2πkn}{N} + x_I (n) sin⁡\frac{2πkn}{N}]\)
D. None of the mentioned
Answer» D. None of the mentioned
Discussion
11.

WNk+N/2=?

A. WNk
B. -WNk
C. WN-k
D. None of the mentioned
Answer» C. WN-k
Discussion
12.

Which of the following is true regarding the number of computations required to compute DFT at any one value of ‘k’?

A. 4N-2 real multiplications and 4N real additions
B. 4N real multiplications and 4N-4 real additions
C. 4N-2 real multiplications and 4N+2 real additions
D. 4N real multiplications and 4N-2 real additions
Answer» E.
Discussion
13.

Which of the following is true regarding the number of computations required to compute an N-point DFT?

A. N2 complex multiplications and N(N-1) complex additions
B. N2 complex additions and N(N-1) complex multiplications
C. N2 complex multiplications and N(N+1) complex additions
D. N2 complex additions and N(N+1) complex multiplications
Answer» B. N2 complex additions and N(N-1) complex multiplications
Discussion