Digital Signal Processing Laboratory Viva Questions - Part 3

Q.1- How are unwanted frequencies removed prior to digital conversion?

1. Pre-filters
2. Digital signal processing
3. Sample-and-hold circuits
4. All of the above

Q.2- If signal is defined as x(n)=nu(n) it is

1. energy signal
2. power signal
3. neither energy nor power signal
4. energy and power signal

Q.3-

1. Periodic with period 2
2. Periodic with period 4
3. Periodic with period 1
4. Not periodic

Q.4- Symmetric part of is

1. {.,.,.,.,-1/2, -1/2, 0, 0, 0, 0, 0, 0, 0, 1/2, 1/2,.,.,.,.}

2. {.,.,.,.,1/2, 1/2, 1, 1, 1, 1, 1, 1, 1, 1/2, 1/2,.,.,.,.,.}

3. {.,.,.,.,1/2, 1/2, 1, 1, 1, 1, 1, 1, 1, -1/2, -1/2,.,.,.,.}

4. {.,.,.,-1/2, -1/2, 1, 1, 1, 1, 1, 1, 1, 1/2, 1/2,.,.,.,.}

5. None of the above

Q.5- If for , P_e is the power in the even part of x(n) , and P_o is the power in the odd part, which of the following statements are true?

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

Q.6- The even part of a function is

1. 
   
2. 
   
3. 
   
4. Above all

Statement for Q.7 – 8:

Two discrete time system S1 and S2 are connected in cascade to form a new system S as shown in fig.

Q.7- Consider the following statements:

1. If S1 and S2 are linear, then S is linear
2. If S1 and S2 are nonlinear, then S is nonlinear
3. If S1 and S2 are causal, then S is causal
4. If S1 and S2 are time invariant, then S is time invariant

True statements are:

1. a, b, c
2. b, c, d
3. a, c, d
4. All

Q.8 Consider the following statements:

1. If S1 and S2 are linear and time invariant, then interchanging the order does not change the system
2. If S1 and S2 are linear and time varying, then interchanging the order does not change the system

True statements are:

1. Both a and b
2. Only a
3. Only b
4. None

Q.9- Let P be linearity, Q be the time-invariance, R be causality and S be stability. A discrete-time system has the input output relationship,

Where x(n) is the input and y(n) is the output. The above system has the properties

1. P, S but not Q, R
2. P, Q, S but not R
3. P, Q, R, S
4. Q, R, S but not P

Q.10. If the nyquist rate for x_a(t) is f_s . what is the nyquist rate for x_a(t)* x_a(t)?

1. f_s
2. 2 f_S
3. f_s/2

5. None of the above