Skip to content
SmartFigureEdu

EC 3492 Digital Signal Processing question paper, November/December 2023

Download PDFRepeated questions and unit-wise bank

Question Paper Code : 20932

B.E./B.Tech. DEGREE EXAMINATIONS, NOVEMBER/DECEMBER 2023.

Fourth/Fifth Semester

Electronics and Communication Engineering

EC 3492 — DIGITAL SIGNAL PROCESSING

(Common to : Computer and Communication Engineering/Electronics and Telecommunication Engineering/Medical Electronics)

(Regulations 2021)

Time : Three hoursMaximum : 100 marks

Answer ALL questions.

PART A — (10 × 2 = 20 marks)

  1. 1.

    What is zero padding? What are its uses?

  2. 2.

    Determine the unit step response of the LTI system with impulse response, h(n) = a^n u(n), |a| < 1.

  3. 3.

    Give the expression for location of poles of a Chebyshev type I filter.

  4. 4.

    Obtain the direct form - I realization for the system, y(n) = 0.5 y(n - 1) - 0.25 y(n - 2) + x(n) + 0.4 x(n - 1).

  5. 5.

    Define Gibbs phenomenon.

  6. 6.

    Obtain cascade realization with minimum number of multipliers. H(z) = 1/2 + (1/4) z^-1 + (1/4) z^-2 + (1/2) z^-3

  7. 7.

    Compare fixed point and floating point arithmetic.

  8. 8.

    Draw the quantization noise model for a first order system.

  9. 9.

    Define sampling rate conversion.

  10. 10.

    What is the need for anti-aliasing and anti-imaging filters in down-sampling and up-sampling of a signal respectively?

PART B — (5 × 13 = 65 marks)

  1. 11.
    (a)

    Determine and sketch the magnitude and phase response of y(n) + (1/2)[x(n) + x(n - 2)]

  2. Or
  3. (b)

    Determine X(k), for N = 8, using DIT-FFT algorithm for the given function below : x(n) = 2^n

  4. 12.
    (a)

    Design an analog Butterworth filter that has alpha_p = 0.5dB, alpha_s = 22dB, f_p = 10kHz and f_s = 25kHz.

  5. Or
  6. (b)

    Using the bilinear transform design a high-Pass filter, monotonic in pass-band with cut-off frequency of 1000 Hz and down 10 dB at 350 Hz. The sampling frequency is 5000 Hz.

  7. 13.
    (a)

    Design an ideal low-pass filter with a frequency response H_d(e^(jw)) = 1 for -pi/2 <= omega <= pi/2; H_d(e^(jw)) = 0 for pi/2 <= |omega| <= pi. Find the values of h(n) for N = 11.

  8. Or
  9. (b)

    Design a high pass filter using hamming window with a cut-off frequency of 1.2 radians/sec and N = 9.

  10. 14.
    (a)

    Find the steady state variance of the noise in the output due to quantization of input for the first order filter. y(n) = a y(n - 1) + x(n)

  11. Or
  12. (b)

    Consider the following second order IIR filter H(z), find the effect on quantization on pole locations of the given system function in direct form and in cascade form. Take b = 3 bits. H(z) = 1 / ((1 - 0.5z^-1)(1 - 0.45z^-1))

  13. 15.
    (a)

    Discuss the poly-phase structure of interpolator and decimator.

  14. Or
  15. (b)

    Describe the features of adaptive filters and any two applications of adaptive filters.

PART C — (1 × 15 = 15 marks)

  1. 16.
    (a)

    Compute the linear convolution for the following sequence using overlap-save method. x(n) = {1, 2, -1, 2, 3, -2, -3, -1, 1, 1, 2, -1} h(n) = {1, 2}

  2. Or
  3. (b)

    Using impulse invariance with T = 1S, determine H(z) if H(s) = 1 / (s^2 + sqrt(2s) + 1)

Other EC3492 papers