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ECE

ENEE420 Communication Systems

Course Description: Communication is the process by which a message generated at one point is represented by a signal that is transmitted through an imperfect medium to a receiver, where a (hopefully accurate) estimate of the message is reconstructed. Topics to be covered include:

(i) A presentation of continuous waveform modulation techniques (including amplitude modulation and angle modulation techniques), with emphasis on time and frequency representations, bandwidth requirements and power efficiency
(ii) An understanding of analog-to-digital (A/D) and digital-to-analog (D/A) conversions, and of sampling and quantization techniques for implementing these processes
(iii) A discussion of inter-symbol interference, and ways of combating it through baseband pulse shaping
(iv) An introduction to digital modulation techniques
(v) Insights into the role of random processes in communication systems analysis, both as a model for system noise and as a model for message generation

Prerequisite(s): ENEE 324 and completion of all lower-division technical courses in the EE curriculum.

Corequisite(s): None

Course Objectives:

  • Understand the fundamentals of point-to-point communication link design and analysis
  • Develop the basic ideas behind the processes of sampling and quantization
  • Appreciate the comparative merits of different modulation/demodulation, signal processing and error control schemes in analog and digital communication systems
  • Analyze noisy information-bearing signals using frequency and time domain methods

Topics Covered:

  • Amplitude modulation: conventional AM, suppressed carrier AM (DSB-SC), single-sideband AM (SSB) and vestigial sideband AM (VSB) – Time and frequency representations of a signal, bandwidth requirements, power efficiency, coherent and envelope detection
  • Frequency modulation: time/frequency representation, bandwidth requirements, demodulation techniques
  • Performance of AM and FM in the presence of noise
  • Sampling: the Shannon-Nyquist criterion for exact reconstruction of band-limited signals
  • Quantization: uniform quantization, companding and other quantization techniques
  • Pulse code modulation (PCM) and digital telephony
  • An introduction to digital modulation – phase shift keying (PSK), frequency shift keying (FSK), amplitude shift keying (ASK)
  • Optional topics: introduction to Information Theory; data compression; inter-symbol interference and equalization; error control codes