Digital Signal Processing Laboratory Viva Questions - Part 7

Q.1- If Z0 and 1/Z0 are two poles of H(Z). h(n) is stable system when h(n) is
(a) Left sided sequence
(b) right sided sequence
(c) two sided sequence
(d)  anything




Q.2- The above system h(n) can be (i) causal and stable (ii) anti-causal and stable Then the true statements are
(a) (i) and(ii)
(b) Only (i)
(c) Only (ii)
(d) None

Q.3- If y(n)=x(n/k), if n is a multiple of k and y(n)=0, if n is not a multiple of k. If Z=1 is not in ROC, Z=1/2 is in ROC and y(n) is  a two sided sequence. If R1=ROC of X(Z), R2=ROC of Y(Z). Then
a) R1 is subset of  R2
b) R2 is subset of  R1
c) R=R1
d) R2=R1/k
e) None of the above
Q.4 - If x(n) is real and X(Z) have two poles. One of them is complex. Then x(n) can be
a) Right sided sequence
b) Left sided sequence
c) Two-sided sequence
d) Right sided sequence or Left sided sequence



Q.5- If x(n) is left sided sequence and if Z=1 is in ROC. Then
(i) Z=1/2 + j√3/2 is in ROC
(ii)  Z=1+j√3/2 may or may not be in ROC
Then which one is true
a) Only (i)
b) Only (ii)
c) (i) and (ii)
d) None of the above

Q.6- A system has impulse response. The output y(n) to the input x(n) is given by . The input x(n) is

a)
b)
c)
d)

Q.7- The transfer function of a system is given by
                                  
The system is

(a) Causal and stable
(b) Causal, stable and minimum phase
(c)  stable and minimum phase
(d) None of the above



Q.8- The z-transform X(z) of a sequence x(n) is given by . It is given that the ROC of X(z) includes the unit circle. The value of x(0) is
-0.5
0
0.25
0.5

Q.9- If the impulse response of a discrete time system is . Then the system function H(z) is equal to

a)   and the system is stable
b)   and the system is stable
c)   and the system is unstable
d)   and the system is unstable

Q.10- Let  . The unilateral z-transform is
(a)
(b)
(c)
(d)








KEY:
a) c
b) d
c) e
d) d
e) c
f) d
g) d
h) b
i) b