# Digital Signal Processing Important 16 Mark Question and Answer IT 1252

PART –B QUESTIONS
1.Describe the concept of frequency in continuous time and discrete time sinusoidal signals
Ans: Waveforms and Derivation
2.State and prove sampling theorem .
Ans: Statement, Derivation, Reconstrution
3.Explain the classification of DT signals.
Ans: a.Linear and non linear systems.
b.Static and dynamic system
c.Causal and noncausal system
d.Stable and unstable system.
4.State and prove the properties of Z transform.
Ans: 1.Linearity
2.Time shifting
3.Convolution
4.Time reversal
5. Differentiation in Z domain
6. Correlation
7.Multiplication
8.Parseval’s theorem
9.Initial Value theorem
10.Final value theorem
5.Problems on Z transform and inverse Z transform.

6.State and prove the properties of DFT.
Ans: 1.Linearity
2. Time reversal
3.Circular convolution
4.Circular symmetries
5. Symmetry properties
6. Circular correlation
7.Priodicity
8.Parseval’s theorem

7.Explain the methods of filtering long data sequences.
Overlap save method
Diagrams

8.Derive 8 point radix –2 DIT-FFT algorithm.
Ans: Basic butterfly diagram, Derivation, Complete butterfly diagram.

9. Derive 8 point radix –2 DIF-FFT algorithm
Ans: Basic butterfly diagram, Derivation, Complete butterfly diagram.
.
10. Derive 16 point radix –4 DIF-FFT algorithm.
Ans: Basic butterfly diagram, Derivation, Complete butterfly diagram.

11.Draw the structures of IIR filters
Ans: Direct form I
Direct form II
Parallel structure

12.Derive the equation for designing IIR filter using backward difference method.
Ans: maping from S plane to Z plane.
d/dt y(t)=y(nT)-y(nT-T)/T
13. Derive the equation for designing IIR filter using impulse invariant method.
Ans: Maping from S plane to Z plane.
Impulse invariant equation

14. Derive the equation for designing IIR filter using bilinear transformation.
Ans: maping from S plane to Z plane.
Bilinear equation S=2/T(1-Z-1/1+Z-1)

15.Problems IIR filter design

16.Explain the steps involved in the design of FIR filter using window technique.
Ans: Specify the equation of window function
Find h(n)
Find hd(n)=h(n)w(n)
Find H(ω)

17. Explain the steps involved in the design of FIR filter using frequency sampling technique.
Ans: Find G(k) from given Hr(k)
Find H(k)

18. Explain the steps involved in the design of FIR filter using Kaiser window .
Ans: Determine hd(n)
Choose δ
Calculate α
Determine the parameter α s
Choose the parameter
Find N
Calculate yhe window function wk(n)
Find h(n)=wk(n) hd(n)

19. Draw the structures of FIR filters.
Ans: Direct form
Parallel structure
Lattice structure.

20.Problems on design techniques and structures of FIR filters.

21.Explain the different types of representations in digital systems.
Ans:Fixed Point
Floating point
Block floating point

22.Disscuss the different types of quantization errors.
Ans:Input quatization error
Proct quantization error.
Coeffient quantization error

23.Derive the expressions for quatization noise power.
Ans: Input quantization noise power
output quantization noise power

24.Explain the different types of limit cycle oscillations and also the solutions
Ans: Zero input limit cycle oscillations
Overflow input limit cycle oscillations
Solutipn:scaling

25.Explain the construction and operation of channel vocoder with block diagram.
Ans : Block diagram
Explanation.