B.TECH - Semester 4 data communication Question Paper 2020 (sep)
Practice authentic previous year university questions for better exam preparation.
Sample Questions
- Define the following characteristics in relation to the simple sine wave model for an analog signal: (i) Amplitude (ii) Frequency (iii) Phase
- Highlight the differences between circuit switching and packet switching.
- What is Pulse Amplitude Modulation (PAM)'? Specify its role in Pulse Code Modulation(PCM).
- For the given data bits $=1000000111110000011$ and generator polynomial bits 1001010, Find out the CRC code.
- Mention the benefits of a spread spectrum system. State, how spreading can be achieved? Answer any one full questions from each Module. Each question carries 20 marks
- With the neat sketch, explain the physical description, applications and transmission characteristics of the following: (i) Twisted pair (ii) Coaxial Cable (iii) Terrestrial Microwave (iv) Satellite
- (a) Discuss various transmission impairments and how they may affect the information carrying capacity of a communication link.
- (b) Given a channel with an intended capacity of 20 Mbps . The bandwidth of the channel is 3 MHz . What Signal-to-Noise Ratio(SNR) is required in order to achieve this capacity?
- (a) For the bit stream 100010100 sketch the waveform for Manchester and Differential Manchester coding and also discuss the advantages and disadvantages of these coding schemes.
- (b) Explain about the various types of modulation techniques used in analog to analog signals.
- (a) With a neat sketch, explain the QPSK transmitter and receiver. Calculate the error probability for QPSK.
- (b) Find the maximum bit rates for an FSK signal if the bandwidth of the medium is $12,000 \mathrm{~Hz}$ and the difference between the two carriers is 2000 Hz . Transmission is in full duplex mode.
- With an example, explain the principle of convolutional coding technique.
- (a) Define multiplexing. Specify the need for multiplexing in data communication. Also write notes on types of multiplexing.
- (b) Five channels, each with a 100 KHz bandwidth, are to be multiplexed together. What is the minimum bandwidth of the link if there is a need for a guard band of 10 KHz between the channels to prevent interference?
- Explain the data Services available in GPRS. Write about the applications for GPRS. State, how is it different from GSM.
- (a) With a diagram. write about direct sequence spread spectrum in detail.
- (b) Discuss the technology of CDMA. Explain, how is CDMA different from GPRS and GSM?