8. Communication Systems

8. Communication Systems

• 8.1 Basic Elements of Communication Systems

  • Block diagrams of analog and digital communication systems

  • Baseband vs. Bandpass transmission

  • Signal and Noise: definitions, statistical description

  • Noise types (thermal, shot, etc.)

  • Equivalent noise bandwidth and White Gaussian Noise (WGN)

  • Performance metrics: Signal-to-Noise Ratio (SNR), Bit Error Rate (BER), Figure of Merit

  • Additive White Gaussian Noise (AWGN) channel model and noise effects

• 8.2 Analog Modulation and Demodulation

  • Amplitude Modulation (AM): DSB-FC (conventional AM), DSB-SC, SSB-SC, VSB

  • AM modulation and demodulation techniques (envelope detection, coherent detection)

  • Angle Modulation: Frequency Modulation (FM) and Phase Modulation (PM)

  • Spectra of FM/PM signals

  • Pre-emphasis and de-emphasis in FM

• 8.3 Digital Communication and Modulation

  • Digital Modulation Techniques:

    • Binary: ASK (BASK), FSK (BFSK), PSK (BPSK)

    • M-ary schemes: M-PSK, M-FSK

    • QPSK and Quadrature Amplitude Modulation (QAM)

  • Error probability analysis for PSK

  • Matched filter receiver

  • Source coding principles

  • Pulse Code Modulation (PCM)

  • Shannon-Hartley channel capacity theorem

  • Multiplexing concept

• 8.4 Pulse Modulation and Coding

  • Pulse Amplitude Modulation (PAM) and bandwidth considerations

  • Pulse Code Modulation (PCM): encoders/decoders, quantization, quantization error, companding (compressor/expander)

  • Multiplexing in PCM systems

  • Differential PCM (DPCM) and noise

  • Delta Modulation (DM), Adaptive Delta Modulation (ADM), Sigma-Delta Modulation

  • Noise in delta modulation (slope overload, granular noise)

• 8.5 Error Control Coding Techniques

  • Introduction to channel coding and Hamming distance

  • Simple parity codes

  • Block Codes: linear and systematic block codes, cyclic codes

  • Convolutional Codes: encoding, code trees, trellis diagrams, state diagrams

  • Introduction to decoding (e.g., Viterbi algorithm)

• 8.6 Data Communication

  • Overview of data communication and networks

  • Parallel vs. Serial communication

  • Multiplexing Techniques: Frequency Division (FDM), Time Division (TDM), Wavelength Division (WDM)

  • Network topologies (bus, star, ring, mesh)

  • Layered network architecture

  • Overview of the OSI model and TCP/IP protocol suite (layer functions)