Modulation Performance in Fading and Multipath Channels

Wireless & Mobile Communications

This set of Wireless & Mobile Communications MCQs focuses on “Modulation Performance in Fading and Multipath Channels”.

1. Bit error rate provides the information about the type of error.
a) True
b) False

2. Which of the following is specified by a specific number of bit errors occurring in a given transmission?
a) Bit error rate
b) Equally likely event
c) Outage event
d) Exhaustive events

3. Irreducible BER floor is created in frequency selective channels due to ____________
a) Intersymbol interference
b) Random spectral spreading
c) Time varying Doppler spread
d) Blind speed

4. Irreducible BER floor is created in non frequency selective channels due to ____________
a) Intersymbol interference
b) Multipath time delay
c) Time varying Doppler spread
d) Blind speed

5. The performance of BPSK is best is term of BER because _______
a) Symbol offset interference does not exist
b) Existence of cross rail interference
c) No multipath delay
d) Doppler spread

6. High capacity mobile systems are interference limited.
a) True
b) False

7. Which of the following do not impact bit error rate in mobile communication systems?
a) Mobile velocity
b) Channel delay spread
c) Modulation format
d) Base station

8. Coherence time refers to ____________
a) Time required attaining a call with the busy base station
b) Time required for synchronization between the transmitter and the receiver
c) Minimum time for change in magnitude and phase of the channel
d) None of the mentioned

9. Doppler spread refers to _________
a) Signal fading due to Doppler shift in the channel
b) Temporary failure of message transfer
c) Large coherence time of the channel as compared to the delay constraints
d) All of the mentioned

10. A rake receiver uses multiple ______
a) Delay circuits
b) Correlators
c) Detectors
d) Flip flops

Leave a Reply

Your email address will not be published. Required fields are marked *