Anna University - DIGITAL SIGNAL PROCESSING (DSP) - April / May 2008 - Question Paper

B.E./B.Tech. DEGREE EXAMINATION, APRIL/MAY 2008.

Fifth Semester

Electronics and Communication Engineering

EC 333 - DIGITAL SIGNAL PROCESSING

(Common to Bio-Medical Engineering)

Time: Three hours

Maximum: 100 marks
Answer ALL questions.

PART A - (10x2 = 20 marks)

1. Check for linearity and ausa1ity of the system y(n) = Cos wnT.
2. State two properties of Z-transform.
3. Prove that convolution in the time domain is multiplication in the frequency domain.
4. Draw the basic butterfly of DIT - FFT structure.
5. ‘What is limit cycle oscillation?
6. State the advantages and disadvantages of FIR filters.
7. Write the expression for Hanning window.
8. When do you decimate a signal?
9. What is interpolation?
10. What is quantization noise?

Part B

11. (a) (i) Represent the signal y(n) = x(2n)+x(n —1)where x(n) is the input and y(n) is the output. (8)
(ii) Explain the procedure to perform linear and circular convolution. (8)

Or

(b) Explain in detail the steps in the computation of FFT using DIF algorithm. (16)
12. (a) Design a FIR filter with the following characteristics using rectangular
window with M = 7 and determine h (n) (16)

Or

(b) Discuss the various window functions available for constructing linear phase FIR filters. (16)

13. (a) Design Butterworth filter with the following characteristics using bilinear transformation method using T = 1 s. (16)

Or

(b) Explain briefly how Cascade and parallel realization of filters are done. (16)

14. (a) Explain fixed and floating point representation in detail. (16)

Or

(b) Explain the various errors that occur in a DSP system. (16)

15. (a) With a neat block diagram explain decimation and interpolation. (16)

Or

(b) Discuss mean, variance, co-variance of a Discrete Random signal. (16)