2024 question paper
Principles of Communication Engineering
24 questions
Q1a. What is the purpose of pre-emphasis in FM transmission? (i) Reduce low-frequency noise components (ii) Improve signal-to-noise ratio (iii) Suppress higher-frequency (iv) Increase bandwidth20242m
Module 3: Probability & Random Processes
View this question on its own page →What is the purpose of pre-emphasis in FM transmission?
(i) Reduce low-frequency noise components
(ii) Improve signal-to-noise ratio
(iii) Suppress higher-frequency
(iv) Increase bandwidthQ1b. The Viterbi algorithm is used for: (i) Encoding cyclic codes (ii) Decoding convolutional codes (iii) Noise filtering (iv) Error detection20242m
Module 6: Information Coding and Decoding
View this question on its own page →The Viterbi algorithm is used for:
(i) Encoding cyclic codes
(ii) Decoding convolutional codes
(iii) Noise filtering
(iv) Error detectionQ1c. The minimum sampling frequency required to avoid aliasing for a signal with a maximum frequency of 8 kHz is: (i) 8 kHz (ii) 12 kHz (iii) 16 kHz (iv) 20 kHz20242m
Module 4: Pulse Modulation-I
View this question on its own page →The minimum sampling frequency required to avoid aliasing for a signal with a maximum frequency of 8 kHz is:
(i) 8 kHz
(ii) 12 kHz
(iii) 16 kHz
(iv) 20 kHzQ1d. Which of the following is an advantage of PCM over analog modulation techniques? (i) Requires less bandwidth (ii) Higher noise immunity (iii) Simpler receiver design (iv) Lower power requirements20242m
Module 4: Pulse Modulation-I
View this question on its own page →Which of the following is an advantage of PCM over analog modulation techniques?
(i) Requires less bandwidth
(ii) Higher noise immunity
(iii) Simpler receiver design
(iv) Lower power requirementsQ1e. If a noise signal has a mean of 0 and a standard deviation of 1, what is its variance? (i) 0 (ii) 1 (iii) 2 (iv) 420242m
Module 3: Probability & Random Processes
View this question on its own page →If a noise signal has a mean of 0 and a standard deviation of 1, what is its variance?
(i) 0
(ii) 1
(iii) 2
(iv) 4Q1f. Which of the following techniques is used to reduce noise in PCM? (i) Companding (ii) Differential PCM (iii) Delta Modulation (iv) FDM20242m
Module 5: Pulse Modulation-II
View this question on its own page →Which of the following techniques is used to reduce noise in PCM?
(i) Companding
(ii) Differential PCM
(iii) Delta Modulation
(iv) FDMQ1g. What is the main advantage of SSB over DSB? (i) Requires less power (ii) Better noise immunity (iii) Requires less bandwidth (iv) Both (i) & (ii)20242m
Module 1: Analog Modulation
View this question on its own page →What is the main advantage of SSB over DSB?
(i) Requires less power
(ii) Better noise immunity
(iii) Requires less bandwidth
(iv) Both (i) & (ii)Q1h. A QPSK signal consists of how many distinct phase states? (i) 2 (ii) 4 (iii) 8 (iv) 1620242m
Module 2: Digital Modulation
View this question on its own page →A QPSK signal consists of how many distinct phase states?
(i) 2
(ii) 4
(iii) 8
(iv) 16Q1i. A frequency-modulated (FM) signal with a frequency deviation of 75 kHz and a modulating frequency of 5 kHz has a modulation index of: (i) 15 (ii) 50 (iii) 75 (iv) 10020242m
Module 1: Analog Modulation
View this question on its own page →A frequency-modulated (FM) signal with a frequency deviation of 75 kHz and a modulating frequency of 5 kHz has a modulation index of:
(i) 15
(ii) 50
(iii) 75
(iv) 100Q1j. What is the primary factor that determines the Bit Error Rate (BER) in a communication system? (i) Power spectral density (ii) Bandwidth efficiency (iii) Signal-to-noise ratio (SNR) (iv) Carrier frequency20242m
Module 2: Digital Modulation
View this question on its own page →What is the primary factor that determines the Bit Error Rate (BER) in a communication system?
(i) Power spectral density
(ii) Bandwidth efficiency
(iii) Signal-to-noise ratio (SNR)
(iv) Carrier frequencyQ2a. Explain the working principle of Phase Shift Keying (PSK) and its advantages over Amplitude Shift Keying (ASK).20247m
Module 2: Digital Modulation
View this question on its own page →Explain the working principle of Phase Shift Keying (PSK) and its advantages over Amplitude Shift Keying (ASK).
Q2b. Discuss the impact of white noise in amplitude modulation systems and derive the signal-to-noise ratio (SNR).20247m
Module 3: Probability & Random Processes
View this question on its own page →Discuss the impact of white noise in amplitude modulation systems and derive the signal-to-noise ratio (SNR).
Q3a. Derive the bit error rate (BER) expressions for PSK and FSK under additive white Gaussian noise (AWGN).20247m
Module 2: Digital Modulation
View this question on its own page →Derive the bit error rate (BER) expressions for PSK and FSK under additive white Gaussian noise (AWGN).
Q3b. If an AM transmitter operates at 1000 kHz carrier frequency with a total power of 10 kW and modulation index of 0.8, determine the power in the carrier and sidebands.20247m
Module 1: Analog Modulation
View this question on its own page →If an AM transmitter operates at 1000 kHz carrier frequency with a total power of 10 kW and modulation index of 0.8, determine the power in the carrier and sidebands.
Q4a. Explain the concept of probability density function (PDF) and cumulative distribution function (CDF) in random processes.20247m
Module 3: Probability & Random Processes
View this question on its own page →Explain the concept of probability density function (PDF) and cumulative distribution function (CDF) in random processes.
Q4b. Compare Pulse Amplitude Modulation (PAM), Pulse Position Modulation (PPM) and Pulse Code Modulation (PCM) with their applications.20247m
Module 4: Pulse Modulation-I
View this question on its own page →Compare Pulse Amplitude Modulation (PAM), Pulse Position Modulation (PPM) and Pulse Code Modulation (PCM) with their applications.
Q5b. Explain cyclic redundancy check (CRC) and its application in digital communication.20247m
Module 6: Information Coding and Decoding
View this question on its own page →Explain cyclic redundancy check (CRC) and its application in digital communication.
Q6a. A carrier signal c(t) = 10cos(2π x 10^6t) is amplitude modulated by a message signal m(t)= 5 cos(2πx10^3t). Determine the modulation index and sketch the frequency spectrum.20247m
Module 1: Analog Modulation
View this question on its own page →A carrier signal c(t) = 10cos(2π x 10^6t) is amplitude modulated by a message signal m(t)= 5 cos(2πx10^3t). Determine the modulation index and sketch the frequency spectrum.
Q6b. Explain the concept of Differential Pulse Code Modulation (DPCM) and its advantages over PCM.20247m
Module 5: Pulse Modulation-II
View this question on its own page →Explain the concept of Differential Pulse Code Modulation (DPCM) and its advantages over PCM.
Q7a. Compare Amplitude Modulation (AM) and Frequency Modulation (FM) in terms of bandwidth, power efficiency, and noise immunity.20247m
Module 1: Analog Modulation
View this question on its own page →Compare Amplitude Modulation (AM) and Frequency Modulation (FM) in terms of bandwidth, power efficiency, and noise immunity.
Q7b. If a Delta Modulation system has step size of 0.1V and a sampling rate of 10 kHz, determine the maximum input signal frequency without slope overload distortion.20247m
Module 5: Pulse Modulation-II
View this question on its own page →If a Delta Modulation system has step size of 0.1V and a sampling rate of 10 kHz, determine the maximum input signal frequency without slope overload distortion.
Q8. A (7,4) Hamming code is used for error correction. If the received codeword is 1011010, determine the original data and correct the error.202414m
Module 6: Information Coding and Decoding
View this question on its own page →A (7,4) Hamming code is used for error correction. If the received codeword is 1011010, determine the original data and correct the error.
Q9a. Write short note on: Huffman Codes20247m
Module 6: Information Coding and Decoding
View this question on its own page →Write short note on: Huffman Codes
Q9d. Write short note on: Superheterodyne receiver20247m
Module 1: Analog Modulation
View this question on its own page →Write short note on: Superheterodyne receiver