Signal Processing MCQs Part-3

Signal processing

1. In DSP processors, which among the following maintains the track of addresses of input data as well as the coefficients stored in data and program memories?

a. Data Address Generators (DAGs)

b. Program sequences

c. Barrel Shifter

d. MAC

2. FIR filters ________.

A. are non-recursive

B. do not adopt any feedback

C. are recursive

D. use feedback

3. If x(n) and X(k) are an N-point DFT pair, then x(n+N)=x(n).

a) True

b) False

4. If x(n) and X(k) are an N-point DFT pair, then X(k+N)=?

a) X(-k)

b) -X(k)

c) X(k)

d) None of the mentioned

5. If X1(k) and X2(k) are the N-point DFTs of X1(n) and x2(n) respectively, then what is the N-point DFT of x(n)=ax1(n)+bx2(n)?

a) X1(ak)+X2(bk)

b) aX1(k)+bX2(k)

c) eakX1(k)+ebkX2(k)

d) None of the mentioned

6. If x(n) is a complex valued sequence given by x(n)=xR(n)+jxI(n), then what is the DFT of xR(n)?

a) ΣNn=0xR(n)cos2πknN+xI(n)sin2πknN

b) ΣNn=0xR(n)cos2πknN−xI(n)sin2πknN

c) ΣN−1n=0xR(n)cos2πknN−xI(n)sin2πknN

d) ΣN−1n=0xR(n)cos2πknN+xI(n)sin2πknN

7. What is the circular convolution of the sequences X1(n)={2,1,2,1} and x2(n)={1,2,3,4}, find using the DFT and IDFT concepts?

a) {16,16,14,14}

b) {14,16,14,16}

c) {14,14,16,16}

d) None of the mentioned

8. By means of the DFT and IDFT, determine the response of the FIR filter with impulse response h(n)={1,2,3} to the input sequence x(n)={1,2,2,1}?

a) {1,4,11,9,8,3}

b) {1,4,9,11,8,3}

c) {1,4,9,11,3,8}

d) {1,4,9,3,8,11}

9. What is the sequence y(n) that results from the use of four point DFTs if the impulse response is h(n)={1,2,3} and the input sequence x(n)={1,2,2,1}?

a) {9,9,7,11}

b) {1,4,9,11,8,3}

c) {7,9,7,11}

d) {9,7,9,11}

10. What is the highest frequency that is contained in the sampled signal?

a) 2Fs

b) Fs/2

c) Fs

d) None of the mentioned

11. If {x(n)} is the signal to be analyzed, limiting the duration of the sequence to L samples, in the interval 0≤ n≤ L-1, is equivalent to multiplying {x(n)} by?

a) Kaiser window

b) Hamming window

c) Hanning window

d) Rectangular window

12. What is the Fourier transform of rectangular window of length L?

a) sin(ωL2)sin(ω2)ejω(L+1)/2

b) sin(ωL2)sin(ω2)ejω(L−1)/2

c) sin(ωL2)sin(ω2)e−jω(L−1)/2

d) None of the mentioned

13. Which of the following is the advantage of Hanning window over rectangular window?

a) More side lobes

b) Less side lobes

c) More width of main lobe

d) None of the mentioned

14. Which of the following is the disadvantage of Hanning window over rectangular window?

a) More side lobes

b) Less side lobes

c) More width of main lobe

d) None of the mentioned

15. 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)

16. 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 wise

ii) Compute the M-point DFT of each row

iii) Multiply the resulting array by the phase factors WN lq.

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

17. Which of the following is done to convert a continuous time signal into a discrete time signal?

a) Modulating

b) Sampling

c) Differentiating

d) Integrating

18. Which of the following is the odd component of the signal x(t)=e(jt)?

a) cost

b) j*sint

c) j*cost

d) sint

19. Which of the following is the common independent variable for speech signal, EEG and ECG?

a) Time

b) Spatial coordinates

c) Pressure

d) None of the mentioned

20. Which of the following conditions made digital signal processing more advantageous over analog signal processing?

a) Flexibility

b) Accuracy

c) Storage

d) All of the mentioned

21. Which property does y(t)=x(1-t) exhibit?

a) Time scaling

b) Time shifting

c) Reflecting

d) Time shifting and reflecting

22. If x(n)=(0,1,2,3,3,0,0,0) then x(2n) is?

a) (0,2,4,6,6,0,0,0)

b) (0,1,2,3,3,0,0,0)

c) (0,2,3,0,0,0,0,0)

d) None of the mentioned

23. If x(n)=(0,0,1,2,3,4,0,0) then x(n-2) is?

a) (0,0,2,4,6,8,0,0)

b) (0,0,1,2,3,4,0,0)

c) (1,2,3,4,0,0,0,0)

d) (0,0,0,0,1,2,3,4)

24. If x(n)=(0,0,1,1,1,1,1,0) then x(3n+1) is?

a) (0,1,0,0,0,0,0,0)

b) (0,0,1,1,1,1,0,0)

c) (1,1,0,0,0,0,0,0)

d) None of the mentioned

25. If a signal x(t) is processed through a system to obtain the signal (x(t)2), then the system is said to be ____________

a) Linear

b) Non-linear

c) Exponential

d) None of the mentioned