Welcome to Our NSF-ILI Project Page
Optical Communication in Undergraduate Laboratories
Wing C. Kwong and David E. Weissman
Summary
The Engineering Department has obtained support from the
NSF-ILI program for development of a program in the science
and technology of optical communications for a two-year
period in 1998. A comprehensive plan is being developed
to integrate the latest fiber-optic communication technology
into our Electrical Engineering (EE) curriculum in a distributed
and cost-effective way by modifications of existing laboratory and
lecture courses. A series of up-to-date experiments are created to
teach the skills and demonstrate the potential of this technology.
Lecture courses on related subjects are being revised to coordinate
with the laboratory, providing students with necessary and sufficient
background materials.
The subject areas covered by the proposed curricula improvements are
(1) Optical Fiber Theory, Characteristics, and Practice;
(2) Laser Diode Theory, Characteristics, and Operations;
(3) Laser Diode Control Circuit Designs; and
(4) Advanced Fiber-Optic Systems and Demonstrations.
Areas (1) and (2) include classical introductory materials
and offer students hands-on experiences with basic
fiber-optic components. The innovation lies in the last
two areas, in particular (4), which covers advanced
system techniques. The comprehensive nature of these
experiments exposes students to a complete link between
basic theory and an actual system. Students first work with
basic fiber-optic components and state-of-the-art measuring
equipment in the laboratory before getting into the
system-level experiments, giving them an integrated concept
of system implementation and the applications of state-of-the-art
optical measuring equipment.
We hope that this project could serve as a model for other
institutions wishing to start an optical fiber communications
program, or it could serve as a guide to augment their existing
laboratories in this area. While the experiments are sufficient
for a one-semester laboratory and suitable for schools interested
in starting an optical fiber communications program, they can
also be introduced separately (important to those schools with
limited resources or difficulty in creating new courses).
Schools which have fiber-optic experiments can also
use this plan to modify and update their laboratories.
Project Information
Current Situation
In the Electrical Engineering (EE) program in the Department
of Engineering at Hofstra University, students acquire a basic
knowledge of the EE field, with specialized knowledge of
applied electronics, electromagnetics, communications,
microwave systems, and computer engineering. They
also gain a strong foundation in the basic engineering
sciences, with an appreciation for the ethical and
professional requirements and issues facing the engineer.
The EE curriculum is continually being reviewed to determine
if students are aware of and in contact with state-of-the-art
technology. While the curriculum includes courses and
laboratories in electronic devices and circuits, electromagnetic
waves, transmission lines, and communication systems, none of
these include up-to-date instruction in optical fiber communications
technology. It is important that our students learn about the wide
range of opportunities in this field for recent graduates, in both
industry and the many excellent graduate programs across the country.
Since optical fiber communications is a relatively new discipline,
not many schools have been able to acquire all the resources
necessary to include both the subject matter and state-of-the-art
instrumentation into their undergraduate engineering laboratory
curriculum. While we are aware that some relevant courses and
experiments can be found at other engineering schools, we believe
that the specific material and ideas that we will develop in this
project can help them accelerate the modernization of their own
curricula. Recent advances in technology have created new trends
in fiber-optic communications. For example, cable TV companies are
implementing the "fiber-to-the-home" concept, using techniques
such as subcarrier-multiplexing (SCM) in fiber-coax systems,
to provide more TV channels and customer-oriented services to
subscribers. For computer networks, companies are working on
the next generation networks that require wavelength-division
multiplexing (WDM) for computers to simultaneously communicate
through the same optical medium. In addition, the recent
introduction of erbium-doped fiber amplifiers (EDFA's)
opens up a new page in optical fiber communications and
accelerates its development. These recently developed subjects,
also including optical computing and photonic switching, require
inclusion in EE programs that are now challenged to go beyond
the classical optical experiments.
The experiments we are planning can provide students with a
meaningful demonstration of this new technology. Students
first work with the basic fiber-optic components (e.g.,
optical fibers and laser diodes) and state-of-the-art
measuring equipment (e.g., optical power meter and optical
spectrum analyzer) in the laboratory before getting into the
system-level experiments. Knowing the characteristics and
limitations of these components and equipment gives students
a fundamental understanding of the development of the broad
subject of fiber-optic technology and potential problems in
actual system implementation. We propose a comprehensive plan
(which spans the basic principles to advanced fiber-optic
systems) to integrate this technology into the EE curriculum
in a distributed and cost-effective way, which makes full
use of existing resour ces and curriculum.
NSF support will enable the purchase of equipment for creating
a series of fiber-optic experiments that will be introduced
into several existing laboratories. An optical spectrum analyzer
will be utilized for the first time in student laboratory.
In addition to matching funds, the University realizes the
importance of optical technology and allocated some seed money
last year to begin this pilot program. The potential impact of
the program is recognized by industry; Corning Glass Co. is
supporting this effort by donating $3,000 worth of erbium-doped
fibers. The focus of this project will be the modification of
our existing senior laboratory (Communications Netwo rks Lab.,
Engg 178, 1-credit) with 2 new sets of experiments, which will
span almost one-half the course. This development will also have
links to two other EE laboratory courses, which will each receive
one new set of experiments. These will deal with subjects that
intersect both courses. Lecture courses on electronic devices
and circuits, electromagnetic waves, transmission lines, and
communication systems will be revised to coordinate with the
laboratories. The two principle investigators will be responsible
for the initiation, development, and implementation of these new
experiments and will interact with the other EE faculty about
specific activities.
After studying the literature, such as the IEEE Transactions on
Education (last five years), the NSF STIS database, and surveying
the EE programs of some schools, we cannot find any comparable
programs that treat these topics in-depth, so that we are convinced
that our development plan and experiments are important innovations
in undergraduate engineering education. It is the collective,
synergistic combination of these experiments that provides the
potential for emulation at ot her schools. While the experiments
are sufficient for a one-semester laboratory and suitable for
schools interested in starting an optical fiber communications
program, they can also be introduced se parately (important to
those schools with limited resources or difficulty in creating new
courses). Schools which have fiber-optic experiments can also use
this plan to modify and update their laboratories.
Development Plan
This proposal reflects on-going efforts and activities on accommodating
optical fiber communications in our EE curriculum. The innovation lies
in the advanced fiber-optic systems and applications of state-of-the-art
optical measuring equipment. For example, an op tical spectrum
analyzer (OSA), a piece of sophisticated power and wavelength analytic
tool, is used the first time in student laboratory. As an expression
of the University's commitment to this pilot program, $9,000 of seed
money was allocated from its budget to implement the experiments in
the first subject area of the plan last year. This is in addition to
the matching funds th e University is prepared to provide. As a result,
fifteen of our seniors were able to perform some fiber-optic
experiments last year. We received very positive responses from
the students, who believed this enhanced their possible employability
in this critical field of telecommunicatio ns. A donation of
erbium-doped fibers (worth $3,000) has been received from the
Corning Glass Co., showing the interest in our program by a
leading manufacturer. We are convinced that the proposed experiments
are suitable for our senior students and we have designed the
program to match the level of faculty expertise and equipment
resources to the need of our students. It is our intention to
stimulate the interest of our students in this technology and to
challenge them to achieve their full potential.
The four subject areas covered by the proposed curricula
improvements are (i) Optical Fiber Theory, Characteristics,
and Practice; (ii) Laser Diode Theory, Characteristics,
and Operations; (iii) Laser Diode Control Circuit Designs;
and (iv) Advanced Fiber-Optic Systems and Demonstrations.
Areas (i) and (ii) include classical introductory materials
and offer students hands-on experiences with basic fiber-optic
components. The innovation lies in the use of the OSA and
the last two subjects, in particular (iv), which are not
offered in most schools. Students will learn how to use
electronic circuits to control the operations of laser diodes
and the advanced technology in fiber-optic communications.
The comprehensive nature of these experiments exposes students
to a complete link between basic theory and an actual system,
giving them an integrated concept of system implementation
and the applications of state-of-the-art optical measuring
equipment.
Optical fiber communications will be phased into the EE program
as modifications of existing lecture and laboratory courses.
The laboratory courses, Engg 178, 192, and 195, will be modified.
(See course descriptions). Lecture courses, Engg 111, 171, 190, and
193, will be revised to provide students with necessary and
sufficient background materials. All those courses will be
taken by the majority of EE majors. (Engg 190 will become a required
course, replacing Engg 35.) In addition, the project will have
high impact on student design projects, independent study, and
research in courses, such as Engg 151, 143B, and 143C.
The Communications Networks Lab (Engg 178), a one-credit senior
laboratory course, will be affected the most by the proposed
experiments. It was originally created with an NSF-ILI grant
in the early 1970's. Students currently spend about 2.7
hours/week in the labora tory performing experiments on signal
analysis, synthesis, random signals, transmission lines, and wave
propagation systems. At present, the existing experiments
cover only 6 weeks (in a 13-weeks semester). Fiber-optic
experiments in areas (i) and (iv) will cover 7 weeks. One
week will be used to review the necessary material for our
students to acquire enough background a nd to familiarize
with the components and equipment. The junior EE lab, Electronics
Lab (Engg 192), will be modified to allocate two weeks for
the new experiments (in area (ii)) to study the basic operating
characteristics and circuit parameters of laser diodes,
while 2/3 of a session will be spent for equipment orientation;
in particular, the OSA is a powerful and sophisticated tool,
requiring careful student instruction. The senior level Advanced
Electronics Lab (Engg 195) will s chedule two weeks for experiments
(in area (iii)) on laser-diode control circuits. The new ]
experiments in Engg 178 cover the first half of the semester,
while Engg 192 and 195 will use the equipment, each for
only two weeks, in the second half of the semester.
Therefore, there will be no conflict in scheduling the
use of the equipment in the various courses participating in the
program.
1) Optical Fiber Theory, Characteristics, and Practice
Students normally learn the fundamentals of wave propagation and wavegui
des in the
prerequisite course, Electromagnetics Waves and Transmission (Engg 111). Since o
ptical fibers
are a special kind of waveguide, their general characteristics and properties wi
ll be reviewed. The
theoretical and practical aspects of fibers: the materials, geometry, polarizati
on, and propagation
parameters for various glass fibers will also be discussed in the course for abo
ut two weeks.
Students will gain hands-on experience in the Communications Networks La
b (Engg 178).
They will first learn single-mode/multimode fiber preparation, laser-fiber coupl
ing technique,
measurement and relationship of fiber-coupling efficiency, and numerical apertur
e of fibers and
lenses. Fiber propagation loss and attenuation as a function of wavelength due t
o intrinsic loss will
be studied. The energy distribution of light propagated through single-mode and
multimode fibers
will be demonstrated. The factors affecting coupling efficiency between two fibe
rs, such as core-
diameter mismatch, angular misalignment, and end separation, will be investigate
d. The coupling
loss of fiber jumpers (with FC-PC type connectors) in splicing sleeves will be m
easured and
compared with that of various commercial fiber splices, including "fusion splice
". Since most
electro-optic components (e.g., intensity waveguide modulators) are polarization
sensitive, states
of polarization and polarization control of light in a single-mode fiber will al
so be demonstrated.
Although the above experiments are classical, they provide a complete li
nk between the
basic theory and system experiments in area (iv). The procedures are standard an
d they will be
detailed in the laboratory manual. With the University's seed money, we have equ
ipped the
laboratory with two sets of equipment (approximately $4,500/set), including opti
cal power meters,
optical fibers, HeNe lasers, optical mounts and lenses. This provides a clear an
d helpful model for
those schools which have a limited budget and have not yet had equivalent proced
ures in place.
Topics to be covered
not done yet
Laboratory Manual
Experiments in Area 1:
one ZIP file
Experiments in Area 2:
one ZIP file
Experiments in Area 3:
one ZIP file
Experiments in Area 4:
one ZIP file
Achnowledgement and Disclaimer
This material is based upon work supported by the National
Science Foundation under Grant No. 9850470. Any opinions,
findings and conclusions or recomendations expressed in this
material are those of the author(s) and do not necessarily
reflect the views of the National Science Foundation (NSF).
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