Digital Signal Processing Laboratory Viva Questions - Part 10

Q.1- Filters with the ________ characteristic are useful when a rapid roll-off is required because it provides a roll-off rate greater than –20/dB/decade/pole.

1. Butterworth
2. Chebyshev
3. Both Butterworth and Chebyshev
4. None of the above
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Q.2- Which filters has a maximally flat response?

1. Butterworth
2. Chebyshev Type –I
3. Chebyshev Type –II
4. None of the above

Q.3- The critical frequency is defined as the point at which the response drops _________ from the passband.

1. –20 dB
2. –3 dB
3. –6 dB
4. –40 dB

Q.4- Which filters exhibits the most rapid roll-off rate?

1. Butterworth
2. Chebyshev Type –I
3. Chebyshev Type –II
4. None of the above

Q.5- Match the following and choose the correct combination

Group 1 Group 2

E. Flat pass band (low pass filter) 1. Chebyshev Type I

F. Equiripple stop band (low pass filter) 2. Butterworth

G. All pole with fastest transition band for a given order 3. Chebyshev Type II

1. E-3, F-1, G-2
2. E-3, F-2, G-1
3. E-2, F-3, G-1
4. None of the above

Q.6- IIR filters

1. are lower in order than FIR filters which meet the same specifications.

2. The poles of the Butterworth filter occur on a circle of radius Ω_c at equally spaced points

3. have multiple feedback terms

1. Only 1
2. Both 1 and 2
3. Both 1 and 3
4. All of the above

Q.7- Determine the order of a type I chebyshev filter that has a 1-dB ripple in the pass band, a cutoff frequency Ω_p = 1000π, a stop band frequency of 2000 π, and a attenuation of a 40dB or more for Ω > Ω_s .

1. 3
2. 5
3. 4
4. 6

Q.8- Determine the order of a low pass Butterworth filter that has a 3 dB bandwidth of 500 Hz and an attenuation of 40 dB at 1000Hz.

1. 5
2. 6
3. 7
4. 8

Q.9- Transform a single pole Lowpass Butterworth filter with system function

In to a Highpass filter with pass band edge cutoff frequency 3 KHz.

1. 
   
2. 
   
3. 
   
4. None of the above

Q.10- Transform a single pole Lowpass Butterworth filter with system function

In to a Bandstop filter with upper and lower band edge frequencies 2 KHz and 1KHz, respectively.

1. 
   
2. 
   
3. 
   
4. None of the above

Ans. Key:

1. b
2. a
3. b
4. b
5. c
6. d
7. c
8. c
9. a
10. a