EE511 FALL 2005
INTRODUCTION TO COMMUNICATION
SYSTEMS
12-15-05: 9pm
SYLLABUS
Home work and
class schedule
V3 Data (ABlist05.m)
V3
DSSS Description
FINAL PROJECT
RESULTS
“So much bandwidth
to use, so little noise”
FIRST PLACE:
The Terminator and Whatever
SECOND PLACE: Tyler
THIRD PLACE: The Destroyers
GROUP
BITS/PACKET
DATE
COMMENT
1. The_Terminator:
Jon Fiorelli, Harish, 524,288 12-14-05 Broke the Bank!
Zhenzhou and Shantilal
2. Whatever: Van Yadack,
Nan Hu 524,288 12-15-05 2nd group to break
the Bank!
3. Tyler:
Tyler J. Doering 251372 12-15-05 Good
4. The Destroyers: Angel Careaga, James Powell, 87381 12-15-05 Good
Mamode Ufomata and Dennis Nainan
5. Shockers: Jessica Woodson, Jeremy
Byrd, 87380 12-15-05 Good
Anne Wheatley and Michael Stewart.
SCORING: This is a competitive
format so the scoring is based on a dynamic scale. The score is SCORE = A * Nbit
+ B where A and B are determined from the following two equations:
100
= A * Nbmax + B
80
= A * 65536 + B
where Nbmax is the highest number
of bits transmitted and received without error. The baseline ran at 65536 bits.
PROTOCOL
for FINAL PROJECT
updated 11-12-04 (NOT UPDATED FOR 2005
YET)
Student sends the bit matrix size,
modulator and demodulator m files to instructor. All the files sent to the
instructor have the "groupname" as a prefix
so the instructor can keep the track of the individual group m files and data.
1. BIT MATRIX SIZE (student sends
this to instructor): The student is ranked by the total number of bits that can
be transmitted through the channel. The bit matrix is 2 dimensional. It has a
length Nbit (column dimension) and a width of Nseq (row dimension). These values, named "Nbit" and "Nseq",
along with a character string containing "groupname",
they are stored in a file called "groupname_Bsize.mat."
An example m file is "groupname_createBsize.m".
Group sends instructor this m file to initiate test.
2. BIT MATRIX (instructor generates
this based on groupnameBsize values): The bit matrix
is generated and stored in a file called groupname_B.mat
and the matrix is called B. A sample code that will generate a
Nseq x Nbit bit matrix B is
"Bgen05.m." I will use Bgen to generate a random sequence of bits of the size
specified by the student in "groupnameBsize.mat."
3. MODULATOR (student sends the
modulator m file to the instructor): A modulator m file by the name "groupname_modulator.m"
will be sent to the instructor. Its input is the file named "groupname_B.mat." The program will create a 1 x N real
vector "s" and a Nseq x N, bit check
matrix, called "Bcheck." The signal vector
will be stored in "groupname_signal.mat"
and the bit check matrix is stored in "groupname_Bcheck.mat."
The length is N=524288=65536*8. The Bcheck matrix (Nseq x N) has 3 element values +1 for a bit value of
"1" to be present, -1 for a bit value of "0" to be
present and 0 for "don't care."
4. CHANNEL (instructor will run
this program, channel05.m, on vector s). The channel will do
three things, lowpass plus bandpass
filter and then add noise. The signal vector s0 is convolved with the
Butterworth low pass filter of order 8 and fc=(N/16)/5,
yielding a bandlimited signal vector s. Added to this
is a bandpass component with bandwidth of about
(N/16) and center frequency of 3*(N/16). The noise is based on the value
sigma=0.2*(max(s)-min(s)) and is generated by w=sigma*randn(1,N). The noisy vector
is sn=s+w. The output of
the channel will be a real one dimensional vector, "r", of size 1xN.
This r vector will be stored in groupname_r.mat.
5. DEMODULATOR/BINARIZER (student
sends the demodulator.m file to the instructor): A
demodulator file by the name "groupname_demodulator.m"
will be sent to the instructor. Its input file is groupname_r.mat.
Its output will be a Nseq x N real matrix. Each row
of the matrix will represent the demodulated and binarized
bit stream defined in B. This output will be stored in "Bs" and saved
to the file groupname_Bs.mat. NOTE: The demodulator
should also binarize the signals in Bs to have values
of either 1 or 0.
6. BIT CHECK (instructor will run bitcheck, bitcheck05.m, to test the students
data for errors): The instructor will run a program that will input the groupname_B.mat file, groupname_Bcheck.mat
file and the groupname_Bs.mat file. The program will
go to each value of 1 or -1 in the Bcheck matrix and
see if the associated element in the Bs matrix is (1) if Bcheck
is 1, then Bs value must be 1 (above 0.5), (2) if Bcheck
is -1, then Bs must be 0 (below 0.5). For each element of Bcheck
that is 0 (between -0.5 and +0.5) the associated value in Bs is ignored. The
resulting values will be verified with the B matrix. To be acceptable, there
must not be any errors in either the number of ones and zeros or the specific
bit values when compared to B. The results will be posted on the web.
Additional
m files include:
binarize.m
irect.m
lp_butterworth_oN_dft.m
bp_butterworth_oN_dft.m
V7
Mixer and DSBSC Description
FAQs
MATLAB:
- Where
is a manual for MATLAB? Try the library first. Most students only use the
manual in the very beginning of their MATLAB experience. Once into it, the
language is intuitive enough and there are enough sample M files that
learning MATLAB is somewhat self-sustaining without manuals. Type "matlab" to execute intepreter,
"help ?" to see listing of operators, "help" for
listing of functions, "who" to see active variables,
"what" for listing of M files and always use "clear"
to start over again.
- How do
you initialize the dimension of a variable? One way is to initialize its
values by zeros(M,N) or ones(M,N). Ex: A=zeros(10,8) is a 10 x 8 matrix of
zeroes. Another function is "ones" which works the same way as
"zeros". Another method is nested loop, ie.,
1:5 loops from 1 to 5 so A(1:5)=3:7 will store the values 3 to 7 in the
first 5 elements of A.
