SHRI ANGALAMMAN COLLEGE OF ENGG & TECH., TRICHY – 621105 (An ISO 9001:2008 Certified Institution) Department Of Electronics and Instrumentation Engg. EC1307 – Digital Signal Processing Unit I PART A (2 Marks Questions) 1. What is a deterministic signal? Give an example? 2. What is random signal? 3. Define (a) Periodic (b) Aperodic signal? 4. Define (a) Symmetric (b) Anti-symmetric signal? 5. What are energy and power signal? 6. Define the continuous time signal? 7. Define the Discrete time signal? 8. What is an LTI system? 9. What is the property of recursive and non-recursive system? 10. Define Convolution sum? 11. Sampling theorem? 12. What is aliasing effect? 13. What is an anti aliasing filter? 14. How do you prevent aliasing while sampling a CT signal? 15. Define Convolution sum? PART B (16 Marks Questions) 1. (a) Explain the significance of Nyquist rate and aliasing during the sampling of continuous time signals. (8) (b) Discuss the principle of operation of an analog to digital converter with a neat diagram. (8) 2. Determine the values of power and energy of the following signals. Find whether the signals are power, energy or neither energy nor power signals. (i) x(n) = sin(n/4) (ii) x(n) = e2nu(n) j(n/2+/4) (iii) x(n) = e (v) x(n) = cos(0n) u(n) (iv) x(n) = u(n+2) – u(n – 2) u(n) 3. Determine if the following system are time invariant or time variant. (i) y(n) = x(n) + x(n – 1) (ii) y(n) = x(n/2) (iii) y(n) = x(- n) (iv) y(n) = n x2(n) 4. Determine if the system described by the following input – output equation is linear or non-linear. (i) y(n) = x(n) + 1/x(n – 1) (ii) y(n) = x2(n) (iii) y(n) = n x(n) (iv) y(n) = n x2(n) 5. Discuss the condition for a LSI system to be stable and causal. 6. Draw and explain the following sequences: (i) Unit sample sequence, (ii) Unit step sequence, (iii) Sinusoidal sequence, (iv) Unit ramp sequence and (v) Real exponential sequence Unit II PART A (2 Marks Questions) 1. Define the Z-transform? 2. What is meant by Region of Convergence? 3. State the final value theorem? 4. State the initial value theorem? 5. What are the properties of Region of convergence? 6. What is the relation between Z transform and DTFT? 7. What are the different methods of evaluating inverse Z transform? 8. Define Fourier transform of a sequence. 9. State Parseval’s energy theorem? 10. Define DTFT pair? 11. Determine the frequency response of a discrete time system. 12. State Parseval’s relation in Z-transform 13. Explain the linearity and time shifting property of the Z-transform 14. Determine the Z-transform of x(n) = 8 (n – 3). 15. Define Fourier transform of a sequence and give its symmetry property. PART B (16 Marks Questions) 1. Find the Z- transform of (i) x(n)= n(n – 1 )u(n) (ii) y(n)=an sinn u(n). 2. If the impulse response of a system is h(n)= [1/2(1/4) n+1/2(3/4) n] u(n) find the frequency response. Determine the magnitude of the following frequency response. 3. Determine the Z- transform of the following (i) x(n) = 8 (n ), (ii) x(n) = {3,1,2,5,7,0,1} (iii) x(n) = 8 (n – 10) (iv) x(n) = 8 (n + 10) 4. Find the Z- transform of x(n)= cos 0n for n≥0 5. Determine the inverse Z- transform of x(z) = 1 / ( 1 – 1.5 z -1 + 0.5z-2) 6. Determine the Z- transform of the signal x(n) = n an u(n) Unit III PART A (2 Marks Questions) 1. Define Discrete Fourier Transform pair. 2. List out the properties of DFT? 3. Define discrete Fourier series 4. What do you understand by periodic convolution? 5. Define circular Convolution? 6. Establish the relation between DFT and Z transform? 7. Distinguish between linear and circular convolution? 8. Define linear Convolution? 9. What is meant by overlap add method? 10. What is FFT? 11. What is decimation in time algorithm? 12. Difference between DTFT and DFT? 13. Define discrete time Fourier transform pair for discrete time signal x(n). 14. Why FFT is needed? 15. What is decimation in frequency algorithm? PART B (16 Marks Questions) 1. Describe the DIT radix 2 FFT algorithm to determine N point DFT? 2. State and prove Circular shift property of DFT. 3. An 8 point sequence is given by x(n) = {2, 2, 2, 2, 1, 1, 1, 1} compute 8 point DFT of x(n) by radix 2 DIt FFT. 4. Perform circular convolution of the two sequence graphically x1(n)= {2,1,2,1} and x2(n)= {1,2,3,4}. 5. Find IDFT of y(k) = {1, 0, 1, 0} 6. State and prove the convolution property of DFT. 7. Explain the Decimation in frequency radix 2 FFT algorithm for evaluating Npoint DFT of the given sequence. Draw the signal flow graph N = 8. Unit IV PART A (2 Marks Questions) 1. What are the properties of FIR filter? 2. What is bilinear transformation 3. Enumerate the significant differences between FIR and IIR filters? 4. What is Gibb’s phenomenon? 5. What are the advantages of FIR filters 6. What is prewarping? Why is it employed? 7. What are the requirements for converting a stable analog filter into a stable digital filter? 8. What are the advantages of FIR filter over IIR filter? 9. What is Warping effect? What is its effect on magnitude and phase response? 10. Give any two properties of Butterworth low pass filter? 11. What are the properties of Chebyshev filter? 12. What are the parameters that can be obtained from Chebyshev filter specification 13. Give the expression for location of poles of normalized Butterworth filter. 14. Distinguish between recursive and non recursive realization 15. Draw the direct form I realization structure of a 3 rd order system? PART B (16 Marks Questions) 1. Explain the design of FIR filters using Windows. 2. Write the expressions for the Hamming, Hanning, Barelett and Kasier Windows. 3. Explain the bilinear transformation Techniques. 4. Explain the desirable characteristic of the window function. 5. Draw the frequency response of linear phase FIR filter of order N(odd) with symmetric condition. 6. Design a low pass FIR filter of order 7 with cut off frequency /3 rad/sec using Hanning window. Unit V PART A (2 Marks Questions) 1. What are the classifications of digital signal process? 2. Give some examples for fixed point DSP’s 3. Give some examples for floating point DSP’s 4. What are the applications of PDSPs? 5. What is pipelining? 6. What is pipe line depth? 7. What ate the different stages in pipeling? 8. What is the pipeline depth of TMS320c50 and TMS320c54x? 9. List the various register used with ARAU 10. What is the function of parallel logic unit? 11. What are the general purposes of I/O pins? 12. What is meant by limit cycle oscillations? 13. What is Quantization error? 14. What are the advantages of VLIW architecture? PART B (16 Marks Questions) 1. Discuss the characteristic features of TMS320C50. 2. What is the special capability of ADSP 2181 signal processing chip? Explain its Architecture? 3. Explain Quantization effects in FIR filter. 4. Explain the architecture and salient feature of TMS 320 C54 X 5. Describe the errors introduced by quantization. Explain the impact of quantization of filter coefficient on the location of poles. 6. Explain the different buses and their functions of TMS 320 C54 X processor.