A technology-enhanced learning environment for an optical fiber communications course

Journal of Engineering Education, Oct 2001 by Hinton, H Scott, Gonzalez, Roberto, Tedder, Laura L, Karandikar, Sandeep, Et al

A Technology-Enhanced Learning Environment for an Optical Fiber Communications Course*

ABSTRACT

This paper describes a technology-enhanced learning environment for an undergraduate course on Optical Fiber Communications (http:/ctle.colorado.edu/nsf2000).

I. INTRODUCTION

A technology-enhanced learning environment (TELE) is a learning environment that uses technology to enhance and enrich the learning environment. In this work, a TELE is being created to match the content presentation, interaction, and assessment to the learning styles1 of the students. This personal tailoring of the content to the individual abilities and aptitudes of the learners is possible because of rapid development of the computer and Internet technologies. Using these new technologies, we can provide multiple approaches for different types of learners to learn the same material. For instance, visual and auditory learners can choose to view step-by-- step solutions to special example problems through the use of streaming video. Other learners might choose to read a text-based discussion of the same content without audio/video support. Also, learners that require specific examples will have access to them while other learners can spend their time learning the same principles from more abstract or mathematical descriptions. It is this "content redundancy" that provides the rich learning environment necessary to support the wide range of different learners needs and abilities.

II. COURSE CONTENT

The content in this TELE is organized into Topics, Concepts, and Principles. Topics, which are analogous to the chapters in a book, are at the top of the organizational hierarchy and composed of a collection of Concepts. Concepts, on the other hand, are similar to the sections of a book, containing a modest number of interrelated Principles. Finally, Principles are the basic knowledge quanta of this learning environment and consist of basic truths, laws, or assumptions. This TELE works at the Concept layer to develop an understanding of a small set of Principles and then explores their interrelationships within the specific Concept. This relationship between Principles and Concepts will be firther discussed in the section on Concept Graphs.

The content organization of the Optical Fiber Communications course is listed below

Topic #1-Optical Fiber

Concept #:' Optical Propagation in Fiber-Ray Theory

Concept #2: Optical Propagation in Fiber-E&M Mode Theory

Concept #3: Cylindrical Fiber

Concept #4: Single-mode Fiber

Concept #5: Attenuation

Concept #6: Dispersion

Concept #7: Alignment Losses

Concept #8: Splices, Connectors, and Couplers

Concept #9: System Limits

Topic #2-Optical Sources

Concept #1: Introduction to Optical Sources

Concept #2: Semiconductor Emission

Concept #3: Semiconductor Laser Structures

Concept #4: Semiconductor Laser Characteristics

Concept #5: LED Structures

Concept #6: LED Characteristics

Topic #3-Optical Detectors

Concept #1: Detector Properties

Concept #2: Semiconductor Photodiodes

Concept #3: Detectors with Internal Gain

Concept #4: Noise

Concept #5: Receiver SNR

Topic #4-Signal Encoding/Decoding

Concept #1: Modulation Formats

Concept #2: Demodulation Schemes

Concept #3: Receiver Sensitivities

Concept #4: Multicarrier Systems

Topic #5-Optical Amplifiers

Concept #1: Semiconductor Ampl!ers

Concept #2: Fiber Amplifiers

Topic #6-Optical Fiber Systems

Concept #1: Optical Link Budget

Concept #2: System Performance Limits

III. LEARNING SYSTEMS

The learning style model chosen for our TELE is based on the work by Felder & Silverman.1 Below is listed a brief description of the different categories or dimensions of the Felder-Silverman learning style model.

* [Sensing, Intuitive]; Sensing learners (concrete, practical, oriented toward facts and procedures) or Intuitive learners (conceptual, innovative, oriented toward theories and meanings);

* [Visual, Verbal]; Visual learners (prefer visual representations of presented material, e.g. pictures, diagrams, flow charts) or Verbal learners (prefer written and spoken explanations);

* [Inductive, Deductive]; Inductive learners (prefer content organization that proceeds from the specific to the general) or Deductive learners (prefer content organization that proceeds from the general to the specific);

* [Active, Reflective]; Active learners (learn by trying things out, enjoys working with others) or Reflective learners (learn by thinking things through, likes to work alone);

* [Sequential, Global]; Sequential learners (linear, orderly, learn in small incremental steps) or Global learners (holistic, systems thinkers, learn in large leaps).

One of the objectives of our TELE is to provide the necessary content redundancy necessary for each concept to guarantee that each type of learner will be able to learn the materinl in a manner suited to his/her learning style.

A. Concept Learning Centers

The organizational structure used in the TELE to allow the learner to work at the Concept layer is the Concept Learning Center (CLC). The CLC is intended to be the central focus point for learning and understanding the technical content of the course. It is analogous to a table stacked with all the resources a learner needs (textbooks, videos, simulations, etc.) to help them understand a particular concept. While sitting at that table, the leaner can explore all or part of the available resources until they feel that they understand the material. A screenshot of a Concept Learning Center is shown in Figure 1. The resources available in each CLC and the learning styles they support (listed in parentheses) are listed below.