EEL 4514 - Communication Systems and Components - Spring 2005
Dr. John M. Shea
- Final exam information
- Exam 2 information
- Exam 1 is on Thursday, March 17th during 4th and 5th periods
in the usual room, NEB 202.
- The TA's office hours will be 5th period Tuesday, 6th period
Thursday, and by e-mail.
- I mentioned that you can build a simple parabolic reflector
to improve the performance of your wireless LAN (in one direction!).
The template I used is for the
from freeantennas.com, but they also have some other templates.
- Please read the course syllabus
- Lecture Materials
- Quiz Solutions
- Homework 1, due Feb. 1
- Homework 2, due Feb. 17
- Problem statement
- Solution, part 1
- MATLAB code for problems 5 and 6
- Figure for problem 5. I had meant
to specify a carrier frequency of 1.9 GHz, but I typed 11.9GHz.
This if the 11.9 GHz result. Note the severe variations in received
power with distance. At very short distances, there are not
enough points in the graph to accurately reflect the performance.
As the distance gets very large, there is a last lobe that rolls
off at 20 dB/decade (same as free space). This is a little easier
to see if we either plot the result for a larger distance range or
consider the frequency I intended by looking at the
results for 1.9 GHz carrier freq..
The received power drops from -9 dBm at 1e4 m to -28 dBm at 1e5 m, which
is 19 dB/decade.
- Figure for problem 6. Note how
much faster the power rolls off if the ground reflection coefficient
is -1. In particualr, for large distances, the slope of the curve
is 40 dB/decode (same as exponential path loss with n=4. As before,
this is easier to see if you plot the result out to a larger distance
or consider the performance results for
1.9 GHz. The received power drops from -4 dBm at 1e4 m to
-35 dBm at 1e5 m, a loss of 39 dB/decade.
- Homework 3, due Feb. 24
- Homework 4, due March 11th by 4:45 PM in EB 440.
- Homework 5, due at beginning of class on March 29th
- Homework 6, due April 8 by 4:45 PM in EB 440
- Homework 7, due April 11 by 4:45 PM in EB 440