Thapar University 2006 M.Tech Electronics and Communication Engineering Advanced Digital Signal Processing - Question Paper

SECTION -A

QNo.l

What do you mean linear prediction? Discuss forward and backward linear prediction leading to normal equations? Name the algorithms to solve these normal equations

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QNo.2

a)    Discuss widrow LMS algorithms for adaptive equalization. What are its advantages and what are its limitations?

b)    Discuss the architecture of typical floating point DSP processor. What type memory architecture is followed by DSP processor.

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QNo.3

(a)    Determine 8-point DFT V(k) of the length - 8 real sequence v(n) given below:

V[nJ = { I 2220 1 1 1} t

(b)    Determine the unit step response of the system described by the difference equation

y(n) = 0.9y(n-l) - 0.81 y (n-2) + x(n) under the following conditions

(a)    y(-l)⁼ y (^-2) 0

(b)    y(*l)⁼ y (-2) 1

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QNo.4

(a

) Find the two dimensional convolution n n 14 1

| 2 | 5 3

¹ 0 -11 -1 | 4 |-1 0-10

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(t

d

a

m

) Discuss the spectrum for periodic screte-timc signals. Write the corrcspor so.

nf

and a periodic continuous time and iding analysis and synthesis equations

Qno.5

Implement a two-stage decimator for the following specifications. Sampling rate of the input signal = 20,000 Hz.

M = 100 Passband = 0 to 40 Hz Transition band = 40 to 50 Hz Passband ripple = 0.01 Stop band ripple = 0.002

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SECTION - B

QNo.6

Develop DIT FFT algorithms for decomposing the DFT for N = 6 and draw the flow diagrams for (a) N = 2.3 and (b) N = 3.2 (c) Also, using the FFT algorithm developed in part (b); evaluate the DFT values for x(n) = {1,2,3,4,5,6}.

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Qno.7

a.    Compare the performance of different types of window functions. In what way Kaiser window is superior to other window functions.

b.    Design a digital chebyshev filter to satisfy the constraints 0.707 < | H |1, 0 So)0.2n

I H )e*^w| <0.1, 0.5nSo)<; ir

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