## Digital signal processing - Dec 17

### Electronics Engineering (Semester 7)

Total marks: 80

Total time: 3 Hours
INSTRUCTIONS

(1) Question 1 is compulsory.

(2) Attempt any **three** from the remaining questions.

(3) Draw neat diagrams wherever necessary.

**Q1. Attempt any four**

**1.a.**Differentiate between butterworth and chebyshev filter.

**1.b.**Explain frequency wrapping effect in beginning IIR Filters.

**1.c.**State the relationship between DFS, DFT and z transform.

**1.d.**What is the DTFS. Find DTFS of X(n)={0,1,2,3} with period N=4.

**1.e.**Compare DSP processor and microprocessor.

**2.a.**Comute IDFT of the following sequence using inverse FFT algorithm X(k) = {3,0,3,0,3,0,3,0)

**2.b.**Write down the design steps for FIR filter using the window techniques. Compare windows.

**3.a.**Design analog butterworth filter then has -2 db passband attention of 20 rad/sec and at least -10 db stopband attention at 30 rad/sec.

**3.b**Compute the circular convolution of the sequence using DFT and IDFT, X1(n)={1, 2, 0} and X2(n)= (2,2,1,1)

**4.a.**Given H(s)=[1/(s+1)(s+3)], T=2 seconds. Design digital IIR filter using BLT method. Explain advantage of BI.T method over IIM method.

**4.b.**Design 6th linear phase LPF with cutoff frequency $\pi/2 $ using blackman window.

**5.a.**Design butterworth LPF to meet following specification

Passband gain is 0.89

Passband frequency edge 30Hz

Attenuation 0.20

Stopband edge 75Hz

**5.b.**Design the symmetric FIR LPF where desired frequency response is given as

$\operatorname{Hd}(w)=\left\{\begin{array}{ll}{e^{(-jw)}} & \\ 0 \end{array}\right.$ for $|\mathrm{w}| \leq \mathrm{w}_{0}$ otherwise

**Q6. Write the short note on following (any two)**

**6.a.**Gibb's phenomenon.

**6.b.**Application of DSP in speech and radar Processing

**6.c.**Limit cycle oscillations.