Mobile Communication Quiz | Mobile Communication Multiple Choice Questions and Answers

Questions
1 The modulation technique used for mobile communication systems during world war II was
A Frequency modulation
B Amplitude modulation
C ASK
D FSK

Answer: Frequency modulation
2 Paging systems could be used to
A Voice message
B Send numeric messages
C Send alphanumeric messages
D All of the above

Answer: All of the above
3 Antenna down tilting refers to
A Focusing radio energy towards ground
B Decreasing the S/N ratio at the antenna input
C Decreasing the strength of antenna
D All of the above

Answer: Focusing radio energy towards ground
4 The rainbow pattern seen on a CD is an example of
A Refraction
B Reflection
C Diffraction
D None of the above

Answer: Diffraction
5 Brewster angle is the angle at which
A No reflection occurs at the first medium
B Reflection coefficient is zero
C The wave gets refracted in the direction of source
D Both a and b

Answer: Both a and b
6 Coherence time refers to
A Minimum time for change in magnitude and phase of the channel
B Time required for synchronization between the transmitter and the receiver
C Time required to attain a call with the busy base station
D None of the above

Answer: Minimum time for change in magnitude and phase of the channel
7 Doppler spread refers to
A Large coherence time of the channel as compared to the delay constraints
B Temporary failure of message transfer
C Signal fading due to Doppler shift in the channel
D None of the above

Answer: Signal fading due to Doppler shift in the channel
8 Slow frequency hopping refers to
A One or more symbols transmitted in time interval between frequency hops
B More than one frequency hop during each symbol
C Hopping rate greater than or equal to information symbol rate
D Both a and c are correct

Answer: One or more symbols transmitted in time interval between frequency hops
9 Working of Adaptive Equalizers include
A Training
B Tracking
C Modulation
D Both a and b

Answer: Both a and b
10 The Linear Equalizer may be implemented as
A FIR filter
B Lattice filter
C Low pass filter
D Both a and b

Answer: Both a and b
11 Linear equalizer is also known as
A Transversal filter
B Low pass filter
C Lattice filter
D None of the above

Answer: Transversal filter
12 PCM, DPCM, DM, ADPCM are the types of
A Waveform coders
B Channel allocation for transmission
C Vocoders
D All of the above

Answer: Waveform coders
13 Waveform coders and Vocoders are the types of
A Frequency translation methods
B Modulation technique
C Speech coders
D Channel allocation for transmission

Answer: Speech coders
14 Speech Coders are categorized on the basis of
A Frequency of signal
B Bandwidth of the signal
C Signal compression techniques
D None of the above

Answer: Signal compression techniques
15 Search window of a RAKE receiver is
A Frequency band of the channel
B Range of the time delays
C Range of noise
D All of the above

Answer: Range of the time delays
16 The RAKE receiver involves the steps
A Estimation of transmitted signal, demodulation, bit decision, correlator
B Estimation of transmitted signal, demodulation, correlator, bit decision
C Estimation of transmitted signal, correlator, demodulation, bit decision
D Correlator, estimation of transmitted signal, demodulation, bit decision

Answer: Correlator, estimation of transmitted signal, demodulation, bit decision
17 In time diversity
A Multiple versions of signals are transmitted at different time instants
B Signal is transmitted with different polarization
C The signal is transmitted using multiple channels
D All of the above

Answer: Multiple versions of signals are transmitted at different time instants
18 ———– introduced Frequency Modulation for mobile communication systems in 1935.
A Edwin Armstrong
B Albert Einstein
C Galileo Galilei
D David Bohm

Answer: Edwin Armstrong
19 DECT stands for
A Digital European Cordless Telephone
B Digital European Cellular Telex
C Digitized Emergency Cellular Telephone
D Digital European Cellular Telephone

Answer: Digital European Cordless Telephone
20 World’s first cellular system was developed by
A Nippon Telephone and Telegraph (NTT)
B Bellcore and Motorola
C AT&T Bell Laboratories
D Qualcomm

Answer: Nippon Telephone and Telegraph (NTT)
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