Data Communication & Network -Data Modems MCQs

Q.1 What does the acronym AM stand for in communications?

• A) Amplitude Mode
• B) Amplitude Modulation
• C) Amplitude Model
• D) None

Q.2 How is Amplitude Modulation (AM) defined?

• A) Change in amplitude of the carrier according to modulating signal
• B) Change in frequency of the carrier according to modulating signal
• C) Change in amplitude of the modulating signal according to carrier signal
• D) None

Q.3 What does the frequency spectrum of an AM signal typically consist of?

• A) Carrier frequency
• B) Upper sideband frequency
• C) Lower sideband frequency
• D) All of these

Q.4 The amount of data transmitted over a communication channel in a given amount of time is called?

• A) Bandwidth
• B) Frequency
• C) Noise
• D) None

Q.5 In standard Amplitude Modulation, which of the following remains constant?

• A) Amplitude of the carrier
• B) Frequency of the carrier
• C) Phase of the carrier
• D) Both B & C

Q.6 Which of the following is an indicator or characteristic of analog communication?

• A) AM or FM signal
• B) No numerical coding
• C) Continuous signal with varying amplitude or phase
• D) All of these

Q.7 Which of the following are recognized types of continuous-wave analog modulation?

• A) Phase modulation
• B) Frequency modulation
• C) Amplitude modulation
• D) All of these

Q.8 What is a common advantage of analog communication compared to digital systems?

• A) Data rate is low
• B) Synchronization is not mandatory
• C) Less transmission bandwidth is required
• D) All of these

Q.9 What is the maximum theoretical transmission efficiency of a standard AM signal?

• A) 34.2%
• B) 40%
• C) 33.33%
• D) 32.21%

Q.10 In the AM spectrum, the Lower Side Band (LSB) refers to the frequencies that?

• A) Are below the carrier frequency
• B) Include the carrier frequency
• C) Lie within the AM Spectrum
• D) Both A & C

Q.11 In the AM spectrum, the Upper Side Band (USB) refers to the frequencies that?

• A) Are above the carrier frequency
• B) Include the carrier frequency
• C) Lie within the AM spectrum
• D) Both A & C

Q.12 By which process can a continuous analog signal be converted into a digital signal?

• A) Sampling
• B) Amplitude Modulation
• C) Filtering
• D) Mixing

Q.13 Which of the following is true regarding 'Low Level' Amplitude Modulation?

• A) Modulation occurs at low carrier power
• B) Output power is initially low
• C) Power amplifiers are needed to boost the final signal
• D) All of these

Q.14 Which of the following is true regarding 'High Level' Amplitude Modulation?

• A) Modulation is done at high power levels
• B) Collector modulation is a common method used
• C) Amplifiers boost signals before modulation
• D) All of these

Q.15 Which of the following is a classic example of continuous-wave analog modulation?

• A) PCM
• B) AM
• C) DM
• D) All of these

Q.16 What is the standard Intermediate Frequency (IF) value used in most AM radio receivers?

• A) 430 KHz
• B) 455 KHz
• C) 480 KHz
• D) None

Q.17 What is the imaginary line connecting the peaks of a modulated carrier waveform called?

• A) Peak Line
• B) Maximum amplitude ceiling
• C) Modulation index
• D) Envelope

Q.18 In AM signal analysis, what serves as the reference line for the modulating signal?

• A) Zero Line
• B) Carrier peak line
• C) Modulated peak line
• D) Un-modulated peak line

Q.19 What occurs if the amplitude of the message signal exceeds the amplitude of the carrier signal?

• A) Decay
• B) Distortion
• C) Amplification
• D) None

Q.20 What is the primary negative effect of signal distortion in a communication system?

• A) Total loss
• B) Error information
• C) Attenuated information
• D) Amplified information