- To introduce the concepts of various analog modulations and their spectral characteristics
- To understand the properties of random process
- To know the effect of noise on communication systems
- To study the limits set by Information Theory
UNIT I AMPLITUDE MODULATION 9
Amplitude Modulation- DSBSC, DSBFC, SSB, VSB – Modulation index, Spectra, Power relations and Bandwidth – AM Generation – Square law and Switching modulator, DSBSC Generation –Balanced and Ring Modulator, SSB Generation – Filter, Phase Shift and Third Methods, VSB Generation – Filter Method, Hilbert Transform, Pre-envelope & complex envelope –comparison of different AM techniques, Superheterodyne Receiver
UNIT II ANGLE MODULATION 9
Phase and frequency modulation, Narrow Band and Wide band FM – Modulation index, Spectra,Power relations and Transmission Bandwidth – FM modulation –Direct and Indirect methods, FM Demodulation – FM to AM conversion, FM Discriminator – PLL as FM Demodulator.
UNIT III RANDOM PROCESS 9
Random variables, Random Process, Stationary Processes, Mean, Correlation & Covariance functions, Power Spectral Density, Ergodic Processes, Gaussian Process, Transmission of a Random Process Through a LTI filter.
UNIT IV NOISE CHARACTERIZATION 9
Noise sources – Noise figure, noise temperature and noise bandwidth – Noise in cascaded systems. Representation of Narrow band noise –In-phase and quadrature, Envelope and Phase –Noise performance analysis in AM & FM systems – Threshold effect, Pre-emphasis and deemphasis for FM.
UNIT V SAMPLING & QUANTIZATION 9
Low pass sampling – Aliasing- Signal Reconstruction-Quantization – Uniform & non-uniform quantization – quantization noise – Logarithmic Companding –PAM, PPM, PWM, PCM – TDM,FDM.
TOTAL: 45 PERIODS
At the end of the course, the student should be able to:
- Design AM communication systems
- Design Angle modulated communication systems
- Apply the concepts of Random Process to the design of Communication systems
- Analyze the noise performance of AM and FM systems
- Gain knowledge in sampling and quantization
- 1. J.G.Proakis, M.Salehi, ―Fundamentals of Communication Systems‖, Pearson Education 2014. (UNIT I-IV)
- 2. Simon Haykin, ―Communication Systems‖, 4th Edition, Wiley, 2014.(UNIT I-V)
- 1. B.P.Lathi, ―Modern Digital and Analog Communication Systems‖, 3rd Edition, Oxford University Press, 2007.
- 2. D.Roody, J.Coolen, ―Electronic Communications, 4th edition PHI 2006
- 3. A.Papoulis, ―Probability, Random variables and Stochastic Processes‖, McGraw Hill, 3rd edition, 1991.
- 4. B.Sklar, ―Digital Communications Fundamentals and Applications‖, 2nd Edition Pearson Education 2007
- 5. H P Hsu, Schaum Outline Series – ―Analog and Digital Communications‖ TMH 2006
- 6. Couch.L., “Modern Communication Systems”, Pearson, 2001.