Communication Systems

What you'll learn

• Describe the elements of a communication system and its impairments, work fluently in decibels, and relate pulse duration, bandwidth and SNR using Fourier analysis.
• Analyze DSB-SC, conventional AM, SSB, VSB and analog QAM, calculate modulation index, sideband power and efficiency, and design envelope and coherent detectors.
• Analyze phase and frequency modulation, compute FM spectra with Bessel functions and bandwidth with Carson's rule, and explain FM generation, demodulation, pre-emphasis and threshold.
• Explain superheterodyne, double-conversion, direct-conversion and low-IF receivers, and calculate image frequencies, mixer spurious responses and third-order intermodulation.
• Apply sampling, quantization and companding to analog messages, calculate SQNR and PCM bit rates, and compare differential and adaptive methods for reducing the bit rate.
• Select line codes, apply the Nyquist criterion and raised-cosine pulse shaping to control intersymbol interference, interpret eye diagrams and relate bit rate to bandwidth.
• Model noise as a random process using autocorrelation and power spectral density, and calculate thermal noise, noise figure, cascaded noise with the Friis formula and receiver sensitivity.
• Represent ASK, PSK, QAM and FSK signals in signal space, compare them by minimum distance, bandwidth and envelope, and select a modulation for a given application.
• Derive the matched filter and maximum-likelihood detector, compute bit error rates against E_b/N₀ for common schemes, and convert bit error rates to packet error rates.
• Apply entropy and Shannon capacity to bound achievable performance, and use error-detecting and error-correcting codes, interleaving and ARQ to approach it.
• Prepare link budgets with free-space, two-ray and log-distance models, and size fade margins and diversity for shadowing and multipath fading.
• Design and verify a licence-exempt telemetry link that meets latency, reliability and regulatory requirements in Canada and the United States.