Wednesday, November 23, 2011

# Important Questions in POC PRINCIPLES OF COMMUNICATION 142304 subject for NOV/DEC 2011 AUT ANNA UNIVERSITY OF TECHNOLOGY EXAMINATIONS FOR SECOND YEAR THIRD SEMESTER IT Students

Important Questions in POC   PRINCIPLES OF COMMUNICATION 142304 subject for NOV/DEC 2011 AUT ANNA UNIVERSITY OF TECHNOLOGY EXAMINATIONS FOR SECOND YEAR THIRD SEMESTER IT Students

142304 - PRINCIPLES OF COMMUNICATION

UNIT I

1.      Write short notes on AM power distribution
2.      In angle modulation, explain frequency devation, percent modulation, phase deviation and modulation index with suitable example
3.      Compare FM and AM
4.      Explain AM voltage distribution and AM power distribution
5.      Derive the relationship between the voltage amplitudes of the side band frequencies and the carrier and draw the frequency spectrum
6.      Derive an expression for the Amplitude modulated signal and draw its frequency   spectrum

UNIT II
1.   What is known as Binary phase shift keying? Discuss in detail the BPSK transmitter         and Receiver and also obtain the minimum double sided Nyquist bandwidth
2.   Explain the principle of FSK transmitter and receiver
3.   Explain QPSK transmitter and receiver. Give bandwidth, baud, and its relevant  equations with neat constellation and output waveforms
4.   Illustrate the concept of 8 QAM transmitter with the truth table
5.   Compare the various types of digital modulation techniques.

UNIT III

1.   Explain ISI for NRZ input signal. Discuss about the causes of ISI.
2.   What is called companding? Briefly discuss the Analog companding   and  digital companding
3.   Explain the elements of PCM system with a neat block diagram
4.   Describe the operations of DPCM system with relevant diagram
5.   Determine 12-bit linear code, 8-bit compressed code, the decoded 12- bit code, the c    quantization error and compression error for a resolution of 0.01 voltage for analog  sample voltages of a) 0.083V b) -0.398Vc) +9.234V d) -20.124 V

UNIT IV

1.   Write short notes on Frequency hop spread spectrum.
2.   Discuss in detail about TDMA and CDMA
3.   Give a detailed account of multiple access techniques
4.   Discuss the frequency HOP spread spectrum with suitable diagram
5.   Explain CDMA System with its features. Explain the various problems available in CDMA system. Compare TDMA & FDMA

UNIT V

1.   Describe a satellite communication system with a suitable block diagram
2.   Enumerate the elements of an optical fiber transmission link.
3.   Write in detail on LEO and GEO orbits
4.   Draw the neat diagram of satellite system link model. Explain its each part in detail.
5.   Briefly describe the function of Optical Detectors.