Digital Communications Syllabus


Subject Code:56026 L:3 T/P/D:1 Credits:3 Int. Marks:25 Ext. Marks:75 Total Marks:100
UNIT I: Elements of Digital Communication Systems:

Elements of Digital Communication Systems: Model of Digital Communication Systems, Digital Representation of Analog Signal, Certain issues in Digital Transmission, Advantages of Digital Communication Systems, Bandwidth-S/N tradeoff, Hartley Shannon Law, Sampling Theorem

UNIT II: Pulse Code Modulation:

Pulse Code Modulation: PCM Generation and Reconstruction, Quantization noise, Non uniform Quantization and Companding, DPCM, Adaptive DPCM, DM and Adaptive DM. Noise in PCM and DM.

UNIT III: Digital Modulation Techniques:

Digital Modulation Techniques: Introduction, ASK,ASK Modulator, Coherent ASK Detector, Non-Coherent ASK Detector, FSK, Bandwidth and Frequency Spectrum of FSK. Non coherent FSK Detector, Coherent FSK Detector, FSK Detection Using PLL, BPSK, Coherent PSK Detection, QPSK, Differential PSK.

UNIT IV: Baseband transmission and Optimal Reception of Digital Signal:

Baseband transmission and Optimal Reception of Digital Signal: Pulse shaping for optimum transmissions. A Baseband Signal Receiver, Probability of Error. Optimum Receiver, optima! of Coherent Reception. Signal Space Representation and Probability of Error, eye diagrams, Cross talk.

UNIT V: Information Theory:

Information Theory: Information and entropy, conditional entropy and redundancy, Shannon Fano coding, Mutual Information, Information loss due to noise, source codings - Huffman Code, variable length coding, Source coding to Increase average Information per bit. Lossy source coding.

UNIT VI: Linear Block Codes:

Linear Block Codes: Matrix description of Linear Block Codes, Error detection and error Correction capabilities of linear block codes.
Cyclic Codes: Algebraic structure, encoding, syndrome calculation.
Decoding

UNIT VII: Convolution Codes:

Convolution Codes: Encoding. Decoding using State, tree and trellis diagrams. Decoding using Viterbi algorithm. Comparison of Error Rates in Coded and Uncoded Transmission.

UNIT VIII: Spread Spectrum Modulation:

Spread Spectrum Modulation: Use of Spread Spectrum, Direct Sequence Spread Spectrum (DSSS), Code Division Multiple Access, Ranging using DSSS. Frequency Hopping Spread Spectrum, PN - sequences: Generation and Characteristics. Synchronization in Spread Spectrum Systems

TEXT BOOKS:
1. Principles of communication systems - Herbert Taub. Donald L Schiling, Goutam Sana, 3rd Edition,McGraw-Hill, 2008.
2. Digital and Analog Communicator Systems - Sam Shanmugam, John Wiley, 2005.


REFERENCE BOOKS:
1. Digital Communications - John G. Proakis . Masoud salehi – 5th Edition, McGraw-Hill, 2008.
2. Digital Communication - Simon Haykin, Jon Wiley, 2005.
3. Digital Communications - Ian A. Glover, Peter M. Grant, Edition, Pearson Edu., 2008.
4. Communication Systems-B.P. Lathi, BS Publication, 2006.