1. The frequency transformation in the digital domain involves replacing the variable z-1 by a rational function g(z-1).

A. True

B. False

2. The mapping z-1 → g(z-1) must map inside the unit circle in the z-plane into __________

A. Outside the unit circle

B. On the unit circle

C. Inside the unit circle

D. None of the mentioned

3. The unit circle must be mapped outside the unit circle.

A. True

B. False

4. The mapping z-1 → g(z-1) must be __________

A. Low pass

B. High pass

C. Bandpass

D. All-pass

5. What should be the value of |ak| to ensure that a stable filter is transformed into another stable filter?

A. < 1

B. =1

C. > 1

D. 0

6. Which of the following methods are inappropriate to design high pass and many bandpass filters?

A. Impulse invariance

B. Mapping of derivatives

C. Impulse invariance & Mapping of derivatives

D. None of the mentioned

7. The impulse invariance method and mapping of derivatives are inappropriate to use in the designing of high pass and bandpass filters due to the aliasing problems.

A. True

B. False

8. We can employ the analog frequency transformation followed by conversion of the result into the digital domain by use of impulse invariance and mapping the derivatives.

A. True

B. False

9. It is better to perform the mapping from an analog low pass filter into a digital low pass filter by either of these mappings and then perform the frequency transformation in the digital domain.

A. True

B. False

10. In which of the following transformations, it doesn’t matter whether the frequency transformation is performed in the analog domain or in the frequency domain?

A. Impulse invariance

B. Mapping of derivatives

C. Bilinear transformation

D. None of the mentioned

11. Which of the following techniques of designing IIR filters do not involve the conversion of an analog filter into a digital filter?

A. Bilinear transformation

B. Impulse invariance

C. Approximation of derivatives

D. None of the mentioned

12. Using which of the following methods, a digital IIR filter can be directly designed?

A. Pade approximation

B. Least square design in the time domain

C. Least square design in the frequency domain

D. All of the mentioned

13. What is the number of parameters that a filter consists of?

A. M+N+1

B. M+N

C. M+N-1

D. M+N-2

14. The minimization of ε involves the solution of a set of non-linear equations.

A. True

B. False

15. What should be the upper limit of the solution to match h(n) perfectly to the desired response hd(n)?

A. L

B. L+1

C. L-1

D. L+2

16. For how many values of the impulse response, a perfect match is present between h(n) and hd(n)?

A. L

B. M+N+1

C. 2L-M-N-1

D. All of the mentioned

17. The degree to which the design technique produces acceptable filter designs depends in part on the number of filter coefficients selected.

A. True

B. False

18. According to this method of design, the filter should have one of the following in large numbers?

A. Only poles

B. Both poles and zeros

C. Only zeros

D. None of the mentioned

19. Which of the following conditions are in the favor of Pade approximation method?

A. Desired system function is rational

B. Prior knowledge of the number of poles and zeros

C. Desired system function is rational & Prior knowledge of the number of poles and zeros

D. None of the mentioned

20. Which of the following filters will have an impulse response as shown in the below figure?

A. Butterworth filters

B. Type-I Chebyshev filter

C. Type-II Chebyshev filter

D. None of the mentioned

21. For what number of zeros, the approximation is poor?

A. 3

B. 4

C. 5

D. 6

22. Which of the following pairs of M and N will give a perfect match?

A. 3,6

B. 3,4

C. 3,5

D. 4,5

23. Which of the following filters will have an impulse response as shown in the below figure?

A. Butterworth filters

B. Type-I Chebyshev filter

C. Type-II Chebyshev filter

D. None of the mentioned

24. Which of the following filter we use in least-square design methods?

A. All zero

B. All pole

C. Pole-zero

D. Any of the mentioned