DSL Technologies: Fundamentals, Modeling and Simulation Techniques (DS131-97-0)

SynopsisThe recent deployment of digital subscriber line (DSL) technology around the world is rapidly making broadband access for the mass consumer market a reality. DSL technology allows telephone operators to get maximum leverage out of their existing infrastructure by delivering broadband access over existing twisted pair telephone lines. At the heart of DSL lies a plethora of signal processing techniques which enable such high-speed transmission to be achieved over a medium originally designed with only voice-band transmission in mind. The goal of this course is to provide a basic understanding of different DSL technologies and their simulation models through a mixture of lectures, discussions, and laboratory simulations.

What You Will Learn

• Theory and practice of modern DSL technologies
• Monte Carlo simulation techniques of digital communication systems
• Hands-on experience on simulating advanced DSL transceivers

Who Should AttendResearchers, engineers and senior technicians working in telecommunications in the role of:

• Research and development
• Design and testing
• Application engineering
• Product marketing

PrerequisiteBasic knowledge in signal analysis, digital communications, and digital signal processing. Some experience in Matlab programming will be helpful.

Course MethodologyThe participants will first be exposed to the basics of DSL technologies. The design technique and its practical implementation are then covered. This is followed by an exposition to Monte Carlo simulation of digital communications using Matlab, where efficient hands-on simulation techniques are taught. The different blocks of DSL systems will be tested to illustrate the principle. Finally, a realistic DMT-based DSL transceiver incorporating all blocks will be simulated and studied. Course materials will include copies of slides relevant to presentations and other supporting material. There will be Matlab demonstrations for design and simulation of DSL systems.

Course Duration2 days, 9am - 5pm

Course StructureDay 1

• Introduction to DSL
• The telephone loop plant
• DSL reference model
• Evolution and main features of DSL technologies (ADSL full rate, ADSL-Lite "g.Lite", HDSL, HDSL2, HDSL4, SDSL, SHDSL, IDSL, VDSL)
• DSL protocol reference model
• Channel impairments and modeling
• Review and discussion of DSL channel capacity Fundamentals of DSL technologies
• Description of the different blocks used in DSL transceivers
• Single carrier modulation: carrier amplitude modulation (CAP)/ quadrature amplitude modulation (QAM)
• Multicarrier modulation: discrete multitone modulation (DMT)
• Discussion of error coding techniques
• Overview of equalization methods

• Monte Carlo simulation of digital communicatin systems
• Fundamental concepts
• System-level simplifications and sampling rate considerations
• Mapping a problem into a simulation model
• Modeling individual blocks
• Random process modeling and simulation
• Graphical techniques for performance assessment: waveforms, spectrum, eye diagrams, scatter plots, histograms, bit error probability plots, etc.
• Matlab examples
• Resources and implementation suggestions
• Exercises Monte Carlo mulation of a DMT ADSL system using Matlab
• Description of the DMT ADSL system
• Analog-to-digital (A/D) & digital-to-analog (D/A) conversions
• Serial-parallel & parallel-serial operations
• Constellation mapping
• Mirror/IFFT, de-mirror/FFT
• Cyclic prefix to mitigate intersymbol interference (ISI)
• The DSL channel
• Equalization & approximation
• Performance evaluation of the DMT system in noisy channels
• Discussion on bit allocation, channel attenuation, and DSL spectrum estimation