ECE 459 - Fall 2021
Description: This course covers the analog underpinning of analog and digital communication systems: representation of signals and systems in the time and frequency domains; analog modulation schemes; random processes; prediction and noise analysis using random processes; noise sensitivity and bandwidth requirements of modulation schemes. Brief introduction to digital communications. Full description, including course goals and instructional objectives, can be found here.
Credit: 3 undergraduate hours or 3 graduate hours.
Prerequisite: ECE 313.
Course information in course explorer.
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- Synchronous: TR, 9.30am-10.50am, ECEB 3017 (in person) and Echo360 Streaming (remote).
- Asynchronous: Recordings posted on Echo360 once they are processed (usually within a couple of hours).
Lecture Attendance Policy: Active participation in your learning environment is vital to your success in this course.
- We invite relevant questions and comments during live lectures by asking verbally or via the chat function of Echo360.
- Avoid disruptive behavior during the live lectures.
- In order to avoid distracting other students, if you are watching the live stream, please keep your microphone muted if you are not asking a question.
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Prof. Juan Alvarez, alvarez@,
3046 Electrical & Computer Eng Bldg (ECEB), 300-5452.
Teaching Assistant: Shiyi Yang, yang158@.
Communication: Please post your questions on Campuswire (8630), instead of emailing the instructor or TA directly because it is very likely that you're not the only one of enrolled in the course that has that same question. This way, others can take advantage of the responses to your questions, and other students might be able to assist you sooner.
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Active participation in your learning environment is vital to your success in this course.
Campuswire: For discussions and questions regarding course material. Code to join: 8630.
Student online behavior:
In any social interaction, certain rules of etiquette are expected and contribute to more enjoyable and productive communication. The following are tips for interacting online via e-mail or discussion board messages, adapted from guidelines originally compiled by Chuq Von Rospach and Gene Spafford (1995):
- Remember that the person receiving your message is someone like you, deserving and appreciating courtesy and respect.
- Be brief; succinct, thoughtful messages have the greatest effect.
- Your messages reflect on you personally; take time to make sure that you are proud of their form and content.
- Use descriptive subject headings in your e-mails.
- Think about your audience and the relevance of your messages.
- Be careful when you use humor and sarcasm; absent the voice inflections and body language that aid face-to-face communication, Internet messages are easy to misinterpret.
- When making follow-up comments, summarize the parts of the message to which you are responding.
- Avoid repeating what has already been said; needless repetition is ineffective communication.
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Suggested (not required) textbooks:
- J. G. Proakis and M. Salehi, Fundamentals of Communication Systems, 2nd edition, Prentice-Hall, ISBN: 978-0133354850.
- B. P. Lathi and Z. Ding, Modern Digital and Analog Communication Systems, Fifth edition, Oxford University Press, ISBN: 978-0-19-068684-0.
- Custom book for ECE459, ISBN: 978-1269807500 (available at IUB and TIS). It has only the chapters that we cover from the Proakis and Salehi textbook.
- Others are at Grainger in reserve.
Lecture slides: will be posted before each module starts, in case you want to print or download ahead of time.
Lecture slides will have blank spaces for some derivations and for solution of examples to be done during lecture.
Updated slides with the derivations and solutions worked out during lecture will then be posted after each lecture.
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It is the student's responsibility to check that the correct grades are entered in CANVAS.
The final grade will be calculated as follows:
As a rough guideline, we intend to award letter grades as indicated below, where 'm' is the mean and 's' is the standard deviation.
- some type of A if
- some type of B or better if
- some type of C or better if
- some type of D or better if
- max(45,m-2s) < grade < m-s
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Each midterm accounts for 19% of your overall course grade and the final exam accounts for 29% of it.
Exams and reviews for them are scheduled for these dates:
- Exam 1, Thursday, Oct 7, 9.30-10:50am CST
- Exam 2, Thursday, Nov 11, 9.30-10:50am CST.
- Final, Monday Dec. 13, 8:00am-11:00am CST.
No conflict exams: There are no scheduled make-up exams.
If you miss an exam due to illness, injury, family emergency or other reasons beyond your control, you will be asked to provide your professor with an absence letter from the Student Assistance Center in the Office of the Dean of Students. Documentation which validates the absence is required by the Dean's Office to provide the absence letter. The absence letter will serve to verify the reason for your absence from the exam. Your instructor will then take an appropriate action that may include offering an oral examination or written examination.
DRES: Students with documented disabilities must notify the instructor at least two weeks before Exam 1.
- We will use Gradescope to grade the exams, so you will receive an email from Gradescope to log in and see your graded exam.
- If after looking at the posted solutions, you feel there was an inaccuracy in the grading of your exam, you can request a regrade within Gradescope itself.
- Do not submit a regrade asking for more partial credit because you did so much work nor because you think something should be worth more/less that it does. Only regrades regarding inaccurate grading will be addressed.
- Regrades could be subjected a regrading of the entire exam, no just those parts you indicate. Therefore, your grade could go up or down as appropriate.
- Make sure you submit regrade requests by the deadline specified in the email sent out by the instructor once the exams are graded. No regrades will be accepted after the deadline, so do not wait until the last minute to submit it and then run into internet issues.
- You can find copies of some old exams and their solutions below.
- These past exams are provided here so you can identify your misconceptions on course topics and get help on those during office hours. They are not a replacement for attending lectures and reading the textbook.
- We provide both the blank exam and the solutions so that you can follow this procedure:
- Solve the blank exam.
- Compare your solutions to the provided solutions and identify your misconceptions.
- If you first look at the solutions and then solve the blank exam, you will not be able to identify your misconceptions as easily, so that is not a good idea.
- Only looking at the solutions without even trying to solve the problems will be of little/no use.
- Solving multiple past exams without understanding the concepts will not result in a good exam grade.
- These exams are a sample of the type of questions that aim at testing the students’ understanding of the course’s concepts, but there are a myriad of other questions, with the same level of difficulty, that could also test those concepts . You should not expect your exam to include questions like those in these past exams.
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Homework assignment policy:
- Homeworks will account for 30% of your overall course grade.
They will be posted every Tuesday in Gradescope at 12pm CST and will be due the following Tuesday by 12pm CST.
The first homework will be posted on Tuesday, August 24 and will be due the following Tuesday, August 31.
- Submissions will be made via Gradescope. You can join the course there with the entry code P58BJZ, use your UIN as your Student ID #.
- Instructions for uploading your solutions to Gradescope can be found here.
- Instructions on how to scan the pdf of the solutions in Android are here.
- Instructions on how to scan the pdf of the solutions in MacOS are here.
- Late Homeworks will receive no credit.
No exceptions, so don't wait until the last minute to submit it and then run into internet issues.
- In order to account for sickness, travel or internet issues, your two lowest Homework grades will be dropped.
- Make sure you box your final answers and match problem parts accurately in Gradescope, or you will be deducted 5% of the corresponding problem part.
- Make sure that your Homeworks are neat enough to read. Graders has the flexibility to deduct points for lack of neatness.
- Homeworks will include Matlab problems to get practical exposure to the concepts covered during lecture. Please make sure you have access to Matlab. There is information for EWS here and for downloading here.
- Homeworks constitute an essential component of your learning experience in the course and prepare you for your exams in effective ways. Investing time to do your Homeworks with care will pay off when you are taking your exams.
You will be expected to provide detailed explanations of your solutions in order to obtain full credit in your Homeworks. Conversely, solutions lacking full explanations will receive zero credit even when the answer provided may be correct and further incorrect answers without any work shown may lead to 'academic integrity violation' cases being opened against you.
You are encouraged to collaborate to understand the problems in the Homework, but each student should solve the problems individually for submission even if they work together initially to understand how to solve the problems. Copying a joint solution is not acceptable.
Please keep these cautionary remarks in mind as you are working out your Homeworks and avoid submitting unsubstantiated solutions to avoid any misinterpretations as explained above.
- Solutions will be posted in Canvas immediately after the corresponding due date.
- Regrades: You will receive an email from Gradescope so you can log in and see your graded Homework. If after looking at the posted solutions, you feel there was an inaccuracy in the grading of your Homework, you can request a regrade within Gradescope itself.
Make sure you submit regrade requests before noon CST on the Tuesday after your graded assignment is made available via Gradescope. Regrades will not be accepted after that date.
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Office hours will be held in room ECEB 2036 starting August 27, through December 6, except Sep 6, Nov 22 & 26.
- Mondays, 1.30-2.30pm, Prof. Alvarez.
- Mondays, 4-5pm, Shiyi Yang
- Tuedays, 8-9pm, Prof. Alvarez, via Zoom.
- Fridays, 3-4pm, Shiyi Yang.
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End of module questions: At the end of each module, except for the first one, you will create one exam-type question that tests a concept from that module that you deem important and will also provide its solution. Submission of these questions via Canvas within one week of the module being finished in lecture will account for 3% of your overall grade.
- Representation of Signals and Systems
- Ennergy and power signals
- Fourier Transform and bandwidth
- LTI systems
- Bandpass signals and systems
- Hilbert Transform
- Analog Modulation
- Amplitude modulation
- AM, DSB, SSB, VSB, QAM
- Bandwidth and power
- AM radio
- Angle modulation
- FM, PM
- Bandwidth and power
- FM radio
- Probability and Random Processes
- Probability review
- Introduction to random processes
- Distribution and density functions of random processes
- Mean, auto-correlation, and auto-covariance functions
- Stationary random processes
- Stationary, WSS, cyclostationary
- Power spectral density
- Gaussian random processes
- White random processes
- Linear filtering of random processes
- Bandpass random processes
- Noise, narrow band noise
- Noise in Analog Modulation
- Signal-to-noise ratio in amplitude modulation systems
- DSB-SC, SSB
- DSB-TC: small noise
- Signal-to-noise ratios in angle modulation systems
- Small noise
- Pre-emphasis and de-emphasis
- Digital Communication
- Sampling, quantization, quantization noise
- Waveform coding: PCM, DPCM, DM
- Line Codes and Power Spectra of Binary Transmission: on/off, polar, bipolar, Manchester, RZ vs. NRZ
- RZ vs. NRZ, on/off, polar, bipolar, Manchester
- Intersymbol interference (ISI)
- Eye diagrams.
- Digital modulation (PAM, PWM, PPM, ASK, FSK, PSK, QPSK, and QAM)
- Baseband pulse transmission in AWGN: Optimum receiver, detection error probability
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The University of Illinois at Urbana-Champaign Student Code should is very important for you to know.
Students should pay particular attention to Article 1, Part 4: Academic Integrity.
Academic dishonesty may result in a failing grade. Every student is expected to review and abide by the Academic Integrity Policy.
Ignorance is not an excuse for any academic dishonesty. It is your responsibility to read this policy to avoid any misunderstanding.
Do not hesitate to ask the instructor(s) if you are ever in doubt about what constitutes plagiarism, cheating, or any other breach of academic integrity.
The effectiveness of this course is dependent upon the creation of an encouraging and safe classroom environment. Exclusionary, offensive or harmful speech (such as racism, sexism, homophobia, transphobia, etc.) will not be tolerated and in some cases subject to University harassment procedures. We are all responsible for creating a positive and safe environment that allows all students equal respect and comfort. I expect each of you to help establish and maintain and environment where you and your peers can contribute without fear of ridicule or intolerant or offensive language.
Disability Resources and Educational Services (DRES)
To obtain disability-related academic adjustments and/or auxiliary aids, students with disabilities must contact the course instructor and the Disability Resources and Educational Services (DRES) as soon as possible.
To contact DRES, you may visit 1207 S. Oak St., Champaign, call 333-4603, e-mail firstname.lastname@example.org or go to the DRES website.
If you are concerned you have a disability-related condition that is impacting your academic progress, there are academic screening appointments available on campus that can help diagnosis a previously undiagnosed disability by visiting the DRES website and selecting “Sign-Up for an Academic Screening” at the bottom of the page.
Any student who has suppressed their directory information pursuant to Family Educational Rights and Privacy Act (FERPA) should self-identify to the instructor to ensure protection of the privacy of their attendance in this course. Click here for more information on FERPA.
The University of Illinois is committed to combating sexual misconduct. Faculty and staff members are required to report any instances of sexual misconduct to the University’s Title IX and Disability Office. In turn, an individual with the Title IX and Disability Office will provide information about rights and options, including accommodations, support services, the campus disciplinary process, and law enforcement options. A list of the designated University employees who, as counselors, confidential advisors, and medical professionals, do not have this reporting responsibility and can maintain confidentiality, can be found here. Other information about resources and reporting is available here.
Support Resources and Supporting Fellow Students in Distress
As members of the Illinois community, we each have a responsibility to express care and concern for one another. If you come across a classmate whose behavior concerns you, whether in regards to their well-being or yours, we encourage you to refer this behavior to the Student Assistance Center (1-217-333-0050) or online. Based upon your report, staff in the Student Assistance Center reaches out to students to make sure they have the support they need to be healthy and safe. Further, as a Community of Care, we want to support you in your overall wellness. We know that students sometimes face challenges that can impact academic performance (examples include mental health concerns, food insecurity, homelessness, personal emergencies). Should you find that you are managing such a challenge and that it is interfering with your coursework, you are encouraged to contact theStudent Assistance Center (SAC)in the Office of the Dean of Students for support and referrals to campus and/or community resources. The SAC has a Dean on Duty available to see students who walk in, call, or email the office during business hours. For mental health emergencies, you can call 911 or contact the Counseling Center.
Run, hide, fight.
Emergencies can happen anywhere and at any time. It is important that we take a minute to prepare for a situation in which our safety or even our lives could depend on our ability to react quickly. When we’re faced with almost any kind of emergency – like severe weather or if someone is trying to hurt you – we have three options: Run, hide or fight.
Run, hide, fight video.
Leaving the area quickly is the best option if it is safe to do so.
- Take time now to learn the different ways to leave your building.
- Leave personal items behind.
- Assist those who need help, but consider whether doing so puts yourself at risk.
- Alert authorities of the emergency when it is safe to do so.
When you can’t or don’t want to run, take shelter indoors.
- Take time now to learn different ways to seek shelter in your building.
- If severe weather is imminent, go to the nearest indoor storm refuge area.
- If someone is trying to hurt you and you can’t evacuate, get to a place
where you can’t be seen, lock or barricade your area if possible,
silence your phone, don’t make any noise and don’t come out until you
receive an Illini-Alert indicating it is safe to do so.
As a last resort, you may need to fight to increase your chances of survival.
- Think about what kind of common items are in your area which you
can use to defend yourself.
- Team up with others to fight if the situation allows.
- Mentally prepare yourself – you may be in a fight for your life
Please be aware of people with disabilities who may need additional assistance in emergency situations
- police.illinois.edu/safe for more information on how to prepare for emergencies, including
how to run, hide or fight and building floor plans that can show you safe areas.
- emergency.illinois.edu to sign up for Illini-Alert text messages.
- Follow the University of Illinois Police Department on Twitter and Facebook to get regular
updates about campus safety.