This course serves as an introduction to the theory and practice behind many of today's communications systems. 6.450 forms the first of a two-course sequence on digital communication. The second class, 6.451, is offered in the spring. Topics covered include: digital communications at the block diagram level, data compression, Lempel-Ziv algorithm, scalar and vector quantization, sampling and aliasing, the Nyquist criterion, PAM and QAM modulation, signal constellations, finite-energy waveform spaces, detection, and modeling and system design for wireless communication.
Introduction: A layered view of digital communication
Entropy and asymptotic equipartition property
Markov sources and Lempel-Ziv universal codes
High rate quantizers and waveform encoding
Discrete-time fourier transforms and sampling theorem
Nyquist theory, pulse amplitude modulation (PAM), quadrature amplitude modulation (QAM), and frequency translation
Jointly Gaussian random vectors and processes and white Gaussian noise (WGN)
Linear functionals and filtering of random processes
Detection for random vectors and processes
Baseband detection and complex Gaussian processes
Doppler spread, time spread, coherence time, and coherence frequency
Discrete-time baseband models for wireless channels
Detection for flat rayleigh fading and incoherent channels, and rake receivers
Case study — code division multiple access (CDMA)