Digital Communication Techniques

Sampling Theorem, Some applications of sampling theorem.

Quantization of Signals, Quantization error, PCM, Electrical representation of binary digits, PCM System, Companding

Line coding, scrambling

Differential PCM- Linear predicted design

T1 Digital System, Multiplexing T1 lines – The T2, T3 and T4 lines

Delta Modulation, and Adaptive Delta Modulation.

Generation, Transmission, Reception; Spectrum and Geometrical Representation in the Signal Space of BPSK, DPSK, QPSK, QASK, M-ary PSK, BFSK, M-ary FSK, and Minimum Shifting Keying (MSK)

A base band signal Receiver, Peak signal to RMS noise output voltage ratio, probability of error, optimum threshold

optimum receiver for both base band and pass band: calculation of optimum filter transfer function, optimum filter realization using Matched filter, Probability error of the matched filter, optimum filter realization using correlator

Digital Communication Systems – Source, Line coder, Multiplexer, Regenerative repeater; Line Coding- PSD of various line codes, polar signalling, constructing a DC Null in PSD by pulse shaping, On Off signalling, Bipolar signalling; Pulse shaping – ISI and effect, Nyquist first criterion for zero ISI; Scrambling, Digital receiver and regenerative repeaters; Equalizers, Timing extraction, Detection error, Eye Diagram