Top 150+ Solved Digital Communication MCQ Questions Answer
Q. Energy per symbol Es is given as
a. es=eb(log2m)
b. es=eb/(log2m)
c. es=2eb(log2m)
d. es=eb/2(log2m)
Q. The relation between the probability of bit error and probability of symbol error in M-ary orthogonal signalling is
a. m/m-1
b. 2m/m-1
c. (m/2)/m-1
d. m/m+1
Q. The non coherent FSK needs Eb/N0 than coherent FSK.
a. 1db more
b. 1db less
c. 3db more
d. 3db less
Q. Which is easier to implement and is preferred?
a. coherent system
b. non coherent system
c. coherent & non coherent system
d. none of the mentioned
Q. Which is the main system consideration?
a. probability of error
b. system complexity
c. random fading channel
d. all of the mentioned
Q. In the frequency of the carrier signal is varied based on the information in an a digital signal
a. ask
b. psk
c. fsk
d. qam
Q. In the amplitude of the carrier signal is varied based on the information in an a digital signal
a. ask
b. psk
c. fsk
d. qam
Q. In modulation , the bit rate is 8 times the baud rate
a. 8-qam
b. 64-qam
c. 256-qam
d. none of above
Q. In modulation , the baud rate is 1/4 times the bit rate
a. 4-qam
b. 2-psk
c. 4-psk
d. none of above
Q. Which of the following is not a characteristic of PN sequence?
a. balance property
b. autocorrelation property
c. run property
d. non deterministic
Q. PN sequence can be generated using .
a. sequential logic circuits
b. op-amp
c. timer ic
d. mosfet
Q. DSSS system spreads the baseband signal by the baseband pulses with a pseudo noise sequence.
a. adding
b. subtracting
c. multiplying
d. dividing