ECE492K Optical Communications & Photonics. NC State University Fall Semester 2008

Transcription

1 Class Meeting Times / Location ECE492K Optical Communications & Photonics NC State University Fall Semester 2008 Lecture Time / Location: 8:05am 9:20pm, Tues. and Thurs., 1229 EB2 Bldg. Lab Time / Location: Mondays EB2 Rm :05pm-8:30 pm You must be simultaneously registered in one of the laboratories if you register for the course Instructor Contact Information Office Hours Professor: Dr. Leda Lunardi, leda_lunardi@ncsu.edu Office / Phone: MRC Bldg, Room 234D (Centennial Campus), Thursday: 9:30 11 am, in room 2116 EB2 Bldg, with Dr. Lunardi Tuesdays: 12:30-1:30 pm in Rm 3026 EB2 with TA No office hours will be held during University holidays (Labor Day Sept 1; Fall Break Oct 9-10; Oct (I), Thanksgiving Holidays Nov or during finals week (Dec 8-16), and instructor office hours will not be held during the week starting Dec 8. If the instructor will be absent for any professional meetings, office hours may be cancelled. Teaching Assistant Elif Karakaya contact: ekaraka@ncsu.edu Educational Resources (Textbook & Online) Since active student participation is essential to the impact (and fun!) of this course, we strongly encourage students to take advantage of office hours, online resources, library resources, and office hours. We welcome all questions (at least those nominally course or career related) during lecture, labs, or by contacting the Professor or TA directly. Required Textbook: Fiber Optic Communications, Joseph C. Palais, 5th ed, ISBN: Reserve Materials: Several books will be placed in Library (if possible) Course Description, Structure, & Attendance This course examines optical communication systems, with an aim to produce students with a foundation and working knowledge of modern photonics concepts/terminology, major opto-electronic devices and/or components, optical communication systems, and device measurement/handling. As most electrical engineering students have minimal exposure to optics and photonics, we invoke a series of laboratory experiments to explore and demonstrate the most fundamental concepts and devices. This course involves two 75-minute lectures and one three-hour laboratory approximately each week (after the second week of classes). Three in-class tests will be given during the semester, and an individually written final paper assignment will take the place of a final exam. Regular attendance is mandatory, and University policy for absences will be followed. A student may miss one of the tests with a justification (medical, military, jury duty) but a make-up exam at the end of the semester will take place with material from the whole course.

2 This course can be conveniently segmented into three major areas described below. I. Fundamentals of Light, Optics, and Optical Fibers Here we gain the necessary foundation for the rest of the course. We will review basic properties of light, and how to use lenses/mirrors/gratings/filters/etc. in simple optical systems. We then examine the basics of cylindrical and rectangular waveguides. Optical fibers are then studied with an emphasis on the design considerations that go into choosing the appropriate fiber for various applications. II. III. Optical Transmitters and Receivers In this segment, we look at how to get light into the fiber and receive it at the other end. Light sources and detectors are covered in depth. While the basic principles that govern all types of lasers (gas, solid state, fiber, diode) will be studied, we focus on the HeNe laser to show the mathematics. Since signal modulation and speed are critical, driver circuits and bandwidth considerations will be discussed. The advantages and disadvantages of photodiodes, photoconductors, photomultiplier tubes and other optical detectors will be covered, with an emphasis on photodiodes. We also hope to gain an understanding of receiver-design and performance issues including noise, sensitivity, and bandwidth. Optical System Design and Performance With knowledge of optical fiber properties and key photonic devices in hand, we examine the optical design of a telecommunications system and explore some current technologies (esp. Wavelength-Division-Multiplexing) and challenges. Students will be required to investigate a current topic/device within photonics (of their choosing), and to summarize relevant literature into a journal-style report. Important Administrative Dates First Lecture: Registration Deadline: Drop Deadline: Last Lecture: Aug 21, 2008 Aug 26, 2008 Oct 17, 2008 Dec 4, 2008 (No labs will be held during the first week of classes.) Evaluation and Grading Policy A weighted average grade will be calculated as shown at left. As a laboratory-oriented course, all labs and the final paper must be completed for a passing grade. Three in-class tests will be given during the semester, and the individually written final paper assignment will take the place of a final exam. The test dates above are tentative and may change. Laboratory Experiments 25 % Homework 15 % Test 1 (~ Sep 16, during lecture) 15 % Test 2 (~ Oct 23, during lecture) 15 % Test 3 (~ Nov 18, during lecture) 15 % Final Paper (Due on or before 11:00am, Dec 4. Early submission is strongly encouraged!) 15 % It is important to note that the Professor will not be curving grades in this course. The good news is that it is theoretically possible for everyone in the class to get an A (or an F). Your performance depends entirely on how you do, and not on how everyone else in the class does. It is therefore in your best interest to help your classmates in every legal way possible. The conversion system below will be used to convert numerical scores to letter grading. Note that a passing grade is 70 (C-) and that grades below 60 receive F.

3 97 X => A+ 87 X < 90 => B+ 77 X < 80 => C+ 67 X < 70 => D+ 93 X < 97 => A 83 X < 87 => B 73 X < 77 => C 63 X < 67 => D 90 X < 93 => A- 80 X < 83 => B- 70 X < 73 => C- 60 X < 63 => D- There will be a gray area of several points below each of the numerical cutoffs at left (except for A to A+). A student within this gray area may receive the higher grade (e.g. a B+ instead of a B) at the discretion of the Professor. This discretion may depend on several things: your test grades improved steadily over the semester, strong in-class and lab participation, attendance in lecture, etc. Homework Policy Homework assignments will be posted on the course website, and are generally due at the beginning of the Tuesday lecture the following week after being assigned. If you are late, your homework is late. Our intention is to post homework solutions online within two days of the due date. Late Homework Policy Any homework handed in after the due date/time described above will be considered late (unless there you make previous arrangements with the Professor, or can demonstrate an emergency situation after the due date/time). Late homework will be penalized 10% and accepted until 10:00am the day after it was originally due. In this circumstance, you may hand in the assignment in several ways: (a) hardcopy to my office in MRC or (b) scanned images. Laboratory Experiment Policy Since there will be some weeks without a lab experiment, check the course room laboratory to be sure of the schedule. Students will perform the experiments within two-person teams, but hand in individual pre-lab assignments and lab write-ups. Pre-lab assignments will be posted on the course website, and must be handed to the TA at the beginning of the lab section. Without the hardcopy of the Pre-Lab, you will not be permitted to perform the lab experiment it is your ticket in the door. Note that the Pre-Lab assignment is meant to introduce you to the lab, and will therefore not generally demand a lot of time. The lab write-up will be based on properly keeping a laboratory notebook. While this will be different than what most students have done in previous courses, we hope that it will provide a very useful realworld skill that many students may not otherwise learn: how to keep a technical lab notebook. Each lab experiment generally involves three stations, each focusing on a different part of the lab. The student-groups will rotate through each station within the three-hour lab time. The TA and/or Professor will provide a brief introduction to the experiment and assist students as needed to promote timely progress. If a group requires more time for a particular experiment, they will generally need to visit one of the other lab sections on another day (with an open station). Lab and Test Make-up Policy If a student has a non-emergency reason to miss a test or lab, then they MUST contact the Professor. Any emergency absence will require some sort of documentation. A make-up opportunity for each lab experiment will generally be offered the following week, and will be scheduled as closely to the original test-date for a test. Only in extreme circumstances will exceptions to this be allowed. Instructor s Commitment You can expect your instructors to be courteous, respectful, and punctual; to be well organized and prepared for lectures/labs; to answer questions clearly and in a non-negative fashion; to be available during office hours or notify you beforehand if we are unable to keep them; to grade uniformly and consistently according to posted guidelines. We aim to provide you with the best course materials and to go out of our way to assist you in learning the material.

4 For Students with Disabilities Reasonable accommodations will be made for students with verifiable disabilities. In order to take advantage of available accommodations, students must register with Disability Services for Students at the Student Health Center. For more information on NC State s policies on working with students with disabilities, see this link. You instructor and TAs have been and will continue to be as flexible as possible. Academic Integrity University policy will be followed. Note that teamwork is strongly encouraged (as it is an important part of being a successful engineer), but plagiarism/cheating is not be tolerated at all. You are expected to fully understand and author any assignments (homework, lab write-ups, exams, reports) even though you may work on them with your classmates on out-of-class assignments. If you do not meet this standard, it is far better to discuss the situation with the professor than to dig yourself into a hole (i.e. cheating) that will have significant long-term consequences. Policy on Auditing and Satisfactory/Un University policy will be followed for those taking the course with the satisfactory/unsatisfactory or the audit classifications. In simple terms, satisfactory or audit credit will only be given to those students who have a C- or higher final grade and who have followed the regulations in the Evaluation and Grading Policy section above. Online Class Evaluations (new) Schedule: Online class evaluations will be available for students to complete during the last week of class the following dates and time: Fall Session 8 a.m. November 21 through 8 a.m. December 8 Students will receive an message directing them to a website where they can login using their Unity ID and complete evaluations. All evaluations are confidential; instructors will never know how any one student responded to any question, and students will never know the ratings for any particular instructors. Evaluation website: Student help desk: classeval@ncsu.edu More information about ClassEval: Instructional Objectives We aim to produce students with a foundation and working knowledge of modern photonics concepts/terminology, major opto-electronic devices/components, optical communication systems, and device measurement/handling. As most electrical engineering students have minimal exposure to optics and photonics, we will provide the necessary background and invoke a series of laboratory experiments to explore and demonstrate the most fundamental concepts and devices. In order to do well in this course, students must demonstrate the ability to: 1. Analyze the operation of LEDs, laser diodes, and PIN photodetectors (including spectral properties, bandwidth, and circuits) and then apply in optical systems. (ABET Outcomes: a, b, e, k) 2. Explain the principles of optical fibers and contrast single- and multi-mode characteristics. (ABET Outcomes, a, c, e, k) 3. Analyze and design optical communication and fiber optic sensor systems. (ABET Outcomes a, c, e, k)

5 4. Design, build, and demonstrate optical and photonics phenomena/experiments within the handson laboratory as part of a team. (ABET Outcomes: a, b, c, d, e, g, k) 5. Locate, understand, and discuss current technical literature dealing with optical fiber systems. (ABET Outcomes: a, g, i, j) Topics Overview of optical fiber communication systems Review of basic optics and properties of laser light, dispersion, data rates Planar dielectric waveguides and integrated optics Optical fiber waveguides: properties and fabrication Sources, modulation, systems components, and system design Wavelength Division Multiplexing (WDM) systems/components Topics within Laboratory Experiments Overview of laser safety and proper optical fiber handling (including the dangers of eye-damage, electrical shock, burns, glass splinters) Phenomena of diffraction, interference/interferometry, reflection, refraction Optical fiber handling, cleaving/splicing, etc. Optical fiber characterization: core/cladding, numerical aperture, single- and multi-mode LEDs, Laser Diodes, device-to-fiber coupling, GRIN lenses Matrix methods for optical modeling and optical communications system modeling (with PTDS )