Announcements

1/19/2003 - I posted the homework grades.
1/19/2003 - I graded the following selected questions in Homework 2: 1.a (power of sequence) , 2.a (impulse response y), 5 max-min spectral frequency), 6.a (power-delay-profile), 6.b (power-delay profile), 8.a (doppler spread). There may be a mismatch in the question numbers in your homeworks and this question numbers. I was careful about that while grading. (I included the question type above for this reason).
1/18/2003 - I graded the following selected questions in Homework 1: 1.3, 4.1,4.2,4.3,4.4,7.2,9.1,9.2,9.3,9.4 (each 10 points).
1/14/2003 - Final exam grades and statistics are posted. You can access them from here. I suggest you seeing your final exam paper.
1/11/2003 - Final Exam solutions are posted. You can access it from here. Please let me know if you encounter any error in the solutions.
1/8/2003 - Final exam Policy: It will be closed book, closed notes, closed everything exam.
- You are allowed to bring 1 page (not 1 sheet, hence not 2 pages) of cheat sheet, which is filled with whatever you like. The back of the sheets must be empty. The cheat sheet can be at most A4 paper size.
1/8/2003 - Midterm grades are posted. click here to see the grades.
1/6/2003 - About the final exam:
- You are responsible from the following material in the final exam:
  - Course slides
  - Mandatory reading papers (11 papers)
  - The sections of T. Rappaport's book that we have seen in the class (I put the section numbers in the reading-list section of this webpage).
- You are responsible from all the topics that we have covered from the beginning of the classes.
- You can bring a scientific calculator to the exam.
12/28 - The final exam will be on January 10, 2003, Friday. I will later announce the time and place.
12/23 - Read the following paper:
- Pravin Bhagwat, Chatschik Bisdikian, Ibrahim Korpeoglu, Mahmoud Naghshineh, Satish Tripathi. “BlueSky: a cordless networking solution for palmtop computers”. ACM Mobicom '99. Seattle, WA, August 1999.
12/12 - Read the following paper:
- Andrew T. Champbell et al., Design, Implementation and Evaluation of Cellular IP, IEEE Personal Communications, August 2000.
12/12 - Read the following paper:
- Charles E. Perkins, Mobile IP, IEEE Communications Magazine, vol. 35, no. 5, May 1997 pp. 84-86
12/8 - Read the following paper:
- B. P. Crow et al., Investigation of the IEEE 802.11 Medium Access Control (MAC) Sublayer Functions, Infocom, 1997.
12/1 - I posted the midterm exam solution (in PDF) on the course website in Exams section. Please let me know if you encounter a mistake in the solutions.
11/27 - I excluded the MACAW paper from the mandatory reading list. Instead I included MACA paper as mandatory. They are not included in the midterm.
11/27 - The following sections are added as recommended sections to read in modulation chapter: 6.11.intro, 6.11.1, 6.11.2, 6.11.3. They are related to spread spectrum techniques: FHSS and DSSS.
11/27 - Mandatory Reading
- Chapter 9 of TR2001]. The following sections: 9.1, 9.1.1, 9.2, 9.3, 9.4.intro, 9.4.1, 9.4.2, 9.4.3, 9.6.intro, 9.6.1, 9.6.1.1 (not 9.6.1.2), 9.6.2. (Media Access related).
- D. D. Falconer, F. Adachi, B. Gudmundson, Time Division Multiple Access Methods for Wireless Personal Communications, IEEE Communications Magazine, (January 1995), pp. 50-57. (first 2 pages).
- P. Karn, MACA - A New Channel Access Method for Packet Radio. Appeared in the proceedings of the 9th ARRL Computer Networking Conference, London, Ontario, Canada, 1990 (not included in the midterm).
11/25 - We have put the handouts about chapter 6 (modulation) and chapter 9 (multiple access) of the book into the library. You are responsible from the parts of that chapters that we have covered and will be covering on Wednesday (11/27) in the class.
11/25 - You may benefit from a scientific calculator in the exam. I suggest you bringing one.
11/25 - The Policy for the Midterm Exam:
- The exam will be closed book, closed notes, closed homeworks, closed everything!
- You are allowed to bring 1 sheet (2 pages) of cheat sheet. You can fill it with whatever you like!
- The exam will on Friday 29, class-time. I don't know how long it will last..
11/25 - I posted the answers of the homework 1 on the web. Please let me now if you encounter any mistake.
11/21 -I may start taking attendance starting from tomorrows lecture (11/22).
11/21 -We will jump to the second layer on 11/22 friday.
11/20 - Read Chapter 6 of [TR2001]. The following sections: 6.intro, 6.1, 6.2, 6.2.3, 6.3, 6.3.2, 6.3.3 (slope detector), 6.4, 6.4.1, 6.4.2., 6.8, 6.8.1, 6.8.3, 6.9, 6.9.1. Inthis chapter, I expect you to study/learn just as the dept that I showed in the class. Not as deep as in the book.
11/- You are only responsible from the parts of the modulation chapter that we have seed in the class.
11/13 - See this link to obtain frequency domain representations of continuous signals (Fourier Approximation) and enjoy.
11/13 - See this link to obtain time domain representations of continuous signals from their frequency domain representations and enjoy.
11/5 - We had put a handout about DSP into the library. You don't have to read it if the slides are enough for you to understand the basics concepts. It is a recommended reading if slides are not enough.
11/4 - You are responsible from reading the following sections of Chapter 5 of [TR2001]: 5.intro, 5.1, 5.2, 5.3.1, 5.4.intro, 5.4.1, 5.4.2, 5.4.3, 5.5.intro, 5.5.1, 5.5.2, 5.6.
11/4 - A very nice online info about wireless communications: here.
11/4 - See this link for simulation of Rayleigh fading and enjoy. It shows how the received signal strength (amplitude of combined signal) at at receiver changes over time in short-term fading. Yoyu can play with the parameters like amplitudes, phases, and doppler shifts of the multipath components that constitute the received signal.
10/30 - Start reading Chapter 5 of the Book: Small-Scale Fading and Multipath. Start with reading sections 5.1 and 5.2.
10/29 - Homework1: Question 8: Assume the heights of the base stations are zero, i.e, take d1 or d2 as the distance between the base stations and the mobile (don't make it complicated by considering the angles, heights, etc.).
10/29 - You can download GNUPLOT for Windows (wgnuplot) from here. You can use wgnuplot to plot functions and data.
10/24 - Homework1: If not explicitly given, assume an antenna has unity gain (1 or 0dB or 0dBi).
10/21 - I would be glad if you can email me your email address at your earliest possible convenient time, so that I can build a class email list which I can use in the near future to sent urgent messages to the whole class in case it is needed!
10/21- Homework1: In question 8: On the figure, X is the corner of 3 hexagons.
10/21- Homework1: Don't forget to use the new version of the homework, i.e. don't use the hardcopy version that have distributed in the class. There are major differences.
10/21 - Homework1: In question 9: Assume that a cell will always use 1/4 of the all available channels: no matter what.
10/21 - Homework1: In question 9.4: Assume the coverage area of a base station is circular shaped, with radius R, for which you will compute the useful service area.
10/21 - Homework1: In question 9: Hint: Think about the coverage area of a base station as a circle (not a square). But think about the model of a cell as a square when you want to compute the required number of base stations to cover the city.
You can reach the error function tabulation from here.
Question 6.6 of homework-1: Assume the mean received power at the boundary of the cell (d=500m) is -25dBm. In other words, the probability that the received power at the boundary of the cell exceeds -25dBm is 1/2.
In homework 1, if not given, assume gain of the antennas a 1 (unity gain) if needed.
On the example in pages 143-144 of the book, 617dB should be 6.17dB while computing the standard deviation.
I did mistake in relating standard deviation to mean square error in the class. I corrected the respective slide and re-posted.
Question 8 of homework-1: C/I means carrier to interference ratio (also called SIR: signal-to-interference ratio). It is the ratio of the signal strength of the signal that is received from the serving base-station to the signal strength of the signal that is received from the interfering base-station. C and I should be expressed in watts. C/I can be expressed in dB.
I did mistake in explaining the double integral over the area of a circle. I made the correction on the respective slide and re-posted. Basically, the differential area should be approximated as the difference of areas of two sectors (not triangles). It is also correct if you approximate it as a rectangle with dimensions Dr x rDq. rDq gives the length of the circular sector, which is one edge of the rectangle. q is expressed in radians.
0/17 - There are a lot of important corrections and modifications that I made to the homework1. So, please download the latest version from the "Homeworks" section of the course webpage. The latest version is posted there!. Please use that version!
You can access the table for areas under normalized Gaussian distribution. This table is related with the Q-tabulation that we have seen in the class in the following way: This_table(z) = 0.5 - Q_tabulation(z).
10/16 - Homework 1 assigned. You can download it from the course web page.
It is due to Oct 25, 2002, Friday.
10/16 - You can search for the meaning of telecommunication terms that you don't know here.
10/16 - Read the chapter 4 of Rappaport's book. It is in the library - reserve section - under my name. The topic is Large-Scale Path Loss.
The following sections: 4.1, 4.2, 4.4, 4.5.intro, 4.6, 4.7.intro, 4.8.intro, 4.9.intro, 4.9.1, 4.9.2, 4.9.3, 4.10.intro, 4.10.3, 4.10.4, 4.11.intro, 4.11.1, 4.11.2, 4.11.3, 4.12.
11/10 - Read and digest the following paper:
- J. B. Andersen, T. S. Rappaport, S. Yoshida, Propagation Measurements and Models for Wireless Communications Channels, IEEE Communications Magazine, (January 1995), pp. 42-49.
9/10 - We have put some handouts about the topics that we have covered into the reserve section of the library under my name. You should read that material.
9/10 - Read and digest the following papers:
- M. Weiser, The Computer for the Twenty-First Century, Scientific American, Vol. 265, No. 3, (September 1991), pp. 94-104.
- D. Cox, Wireless Personal Communications: What is It?, IEEE Personal Communications Magazine, (April 1995), pp. 20-35.
- H. Forman, J. Zahorjan, The Challenges of Mobile Computing, IEEE Computer, V 27, N 4, (April 1994), pp. 38-47.
- T. La Porta et al., Challenges for Nomadic Computing: Mobility Management and Wireless Communication, ACM/Baltzer Journal of Mobile Networking and Applications, Vol. 1, No. 1, 1996.
The following paper has been put into further reading (optinal) section (it is not mandatory to read):
M. Satyanarayan, Fundamental Challenges in Mobile Computing, M. Satyanarayan, Fifteen ACM Symposium on Principles of Distributed Computing, 1996.
9/23 - The first class is on Wednesday at 15:40 in room 502.
9/23 - If you are an undergraduate and would like to take the course seriously, then come to my office and write your name on the list that is posted on my door. I will decide later how many undergraduates I will allow for the course.