This set of Analog Communications Multiple Choice Questions & Answers (MCQs) focuses on “Disadvantages of Filter Method”.
1. Why sampling is used in communication?
a) for getting higher speed of communication
b) for getting higher efficiency
c) cheaper equipment is required
d) for a better transmission
Explanation: Sampling is the conversion of continuous-time signal to discrete-time signal. It is highly used in communication for getting higher speed of communication.
2. Which two noises are present in Delta Modulation (DM)?
a) Slope overload and Thermal noise
b) Granular and shot noise
c) Slope overload and granular noise
d) Thermal and shot noise
Explanation: Delta modulation is used for transmission of voice information where quality is not the primarily importance. Its drawback is it has two noises namely slope overload and granular noise. So for getting rid from these noises we use ADM (Adaptive Delta Modulation).
3. What is the need of doing Pre emphasis?
a) For boosting of modulating signal voltage
b) For restoring of original signal power
c) For removing amplitude variations due to noise
d) For removing frequency variations
Explanation: It is use for boosting. It boosts the modulating voltages at higher frequencies.
4. Varacter is used for generation of ________
a) PM signals only
b) FM signals only
c) AM signals only
d) PM and FM signals
Explanation: Varacter diode or tuning diode that has a variable capacitance. It is operated as reverse-biased and therefore no current flows. It is mainly used for generation of FM signals only.
5. What will happen in amplitude modulation, if modulation index is more than 1?
a) bandwidth will increase
b) bandwidth will decrease
c) there will be chances of interference
d) waves will get distorted
Explanation: Modulation index tells us the amount by how much the modulated variable of carrier varies. If modulation index is greater than 1 then the wave gets distorted.
6. The adverse effect of noise in communication system can be seen in ________
Explanation: Noise is a sound that is very much unpleasant that causes disturbance. Its adverse effect is highly seen on channel.
7. Which among the following is not an advantage of FM over AM?
a) modulating power required is less
b) low bandwidth is required
c) better noise immunity
d) transmitted power is more useful
Explanation: In frequency modulation, frequency of carrier varies with the modulated wave. It has many advantages over AM but requirement of low bandwidth is not the one.
8. Which of the following is the advantage of base modulation over collector modulation of a class C amplifier?
a) lower modulation power is required
b) higher power output per transistor
c) better efficiency
d) better linearity of modulation
Explanation: Base modulation has many advantage over collector modulation. Its most important use is its requirement of low modulation power.
9. What is the radio frequency range of a frequency modulated signal?
a) 20-80 MHz
b) 100-200 MHz
c) 200-350 MHz
d) 90-105 MHz
Explanation: The standard frequency range of a frequency modulated signal is between 90-105 MHz.
10. Vestigial side band (VSB) is most commonly used in ________
a) Television Transmission
d) Laser Equipments
Explanation: Vestigial side band is highly used in transmission because it requires low bandwidth. It is a type of amplitude modulation technique that encodes data by vary amplitude of a single carrier frequency.
Sanfoundry Global Education & Learning Series – Analog Communications.
To practice all areas of Analog Communications, here is complete set of 1000+ Multiple Choice Questions and Answers.