EE511 FALL 1997

INTRODUCTION TO ANALOG AND DIGITAL COMMUNICATIONS

SETUP AND USAGE OF EE511 NEWSGROUP

DATA BOOKSHELF for data sheets

Updated 12-21-97

PROJECTS

Students will be able to access Labs rooms: 552 AH, 591 AH and 581 AH as listed in the SCHEDULE FOR LABORATORY ACCESS. 552 AH is the EE499 lab so EE499 students have priority...please be courteous.

PROJECT 1: Direct Sequence Spread Spectrum

Each student randomly picks an integer number between -10 and 10. The resulting numbers are recorded and split into two sequences, A[n] and B[n]. Half the class treats the A sequence as the target sequence and B as the noise sequence. The other half of the class treats B as target and A as noise. Using MATLAB, Mathematica, Maple, etc., the students detect their target sequence and suppress their noise sequence using spread spectrum technique.

PROJECT 2: DETECTION AND DIGITIZATION OF ON/OFF KEYING MODULATION

Students will build a square wave generator circuit which will send a finite number (i.e., burst) of modulated pulses to a bandpass filter. A diode detector is used to detect the pulses and a comparitor is used to convert them to binary information.

There are two stages to this system, the transmitter and receiver, respectively. Previous competitions have required the systems to operate from 10 feet to 160 feet (maximum length of hall way) so the received power vary from K/10^2 to K/160^2. The ratio of these is 16^2 = 256. Thus, it is recommended to test the dynamic range of the receiver for 1 to 256 units.

A. Build the transmitter so that it may be tested for output count, frequency and duty cycle. For testing the system performance, use a variable resistor that can vary the output voltage from 0.004 volts to 1 volt peak-to-peak. I suggest forming a voltage divider from say R1 = 256 R2 where R2 is a trim potentiometer. Ex: Let R2=1000 ohms, R1=256,000 ohms.

B. Build a receiver that will detect the transmitter's fundamental frequency. The input to the receiver will be tested, using the transmitter, between 0.004 volts p-p to 1 volt p-p. The output of the transmitter should be a binary value of on or off depending on the presence of the correct frequency pulse. Note that if your supply voltage were +/- 6 volts then the ac input would effectively be +/- 0.5 volts. The comparator range would be about 0 to 4.6 volts ( I subtracted 1.4 volts for 2 Vbe drops) so the gain would be 9.2 = 4.6/0.5 which would yield voltages at the input of the comparator between 0.036 = 9.2 x 0.004 to 4.6 = 9.2 x 0.5.

GROUPS for Project 1(first name is your group representative)

1. Mun Yeong Choy (mychoy0@mik.uky.edu) , Jin Churn Chong, Wei Ping Lor, Tai Chan.

2. Brian Cottongim (brcott0@ewl.uky.edu) , Chris Hughes Email: cahugh@uky.campus.mci.net , Patrick Baisden, Jeff Leuderalbert.

3. Aaron Judge (cajudg00@pop.uky.edu) , Jeff Bowers, Jeff Metze Email: jpmetz00@pop.uky.edu , Paul Upton.

4. Christopher Carr alpha7@uky.campus.mci.net , Bamidele Ali, Joseph Harbeson, Darren Boyd, Rami Alkabra.

5. Clain Hendrix, Kevin Mefford, Rodney White Email: rawhit0@pop.uky.edu , James Wilson.

6. Corey Clark clclar1@pop.uky.edu , Amy Bush acbush0@ewl.uky.edu , Shawn O'Conner, Craig Carpenter.

7. Matt Reed mbreed0@engr.uky.edu , Mark Nolan, John Writt, Wade Allen.

8. John Lemaster johlemaster@uky.campus.mci.net , Marc Leach.



PROJECT 3: Optical Link

The objective of Project #3 is to build and test an optical communications link. The transmitter will transmit a square wave at the groups primary frequency f- and 10 additional measurements will be made uniformly between fc/10Hz and 10 x fcHz. A square wave generator may be used for this measurement. The receiver will receive this wave form and isolate it from ambient and overhead lighting interference. Project #3 does require demonstration of the Project 2 detector/digitization circuitry. There are two types of transmitters used, LED's and LASER DIODES. Each group will choose which transmitter to use for Project #3. The following is the required measurements for these different transducers.
1.a. LED transmitter BEAM PATTERN: No lens is used. The students will make measurements at their specific frequency only. Measurements are made NONUNIFORMLY from 90 degrees to -90 degrees where 0 degrees represents the maximum transmission direction. Typically, students rotate the transmitter on top of polar graph paper. More measurements are made in the region of the maximum beam response than in the sidelobe regions. When the beam pattern is graphed, the peak of the main lobe is scaled to a constant value and other values are plotted relative from this. The beam spread angle is the angle between values having 0.707 magnitude of the main lobe peak. Be sure to record the peak to peak voltage measurements made at each angle. Instructor must observe data but observation of the experiment is not necessary.
1.b. LASER transmitter BEAM PATTERN: There is no reason to rotate and measure the beam pattern of the LASER. Instead, either the transmitter or receiver is laterally translated, in mm, to measure the beam profile. The magnitude is recorded on a rectangular grid. The students should spread the beam, if they have a lens, to about 5 cm wide. If No lens is used then finer measurements should be made. The students will make measurements at their specific frequency only. Measurements are made in increments close enough to indicate the first two spatial harmonics of the laser. There should be two sets of measurements representing the rectangular symmetry if the beam footprint. Be sure to record the peak to peak voltage measurements made at each lateral position. Instructor must observe data but observation of the experiment is not necessary.
2. BOTH LASER and LED systems will be tested for their ability to detect and digitize the signal form project 2. Instructor must observe this.

PROJECT 4:Count and Display Data

Build a circuit to count and display pulses generated in Projects 2 and 3. Project #4 will include the Project #2 and #3 circuitry. Count may be in binary or decimal format.

PRELIMINARIES

0. EE511 baseline system (Distance=160 feet,12-8-97), i.e., all the way.

1. W.A.R.N. GROUP(Distance=80 feet, 12-5-97) Matt Reed mbreed0@engr.uky.edu , Mark Nolan, John Writt, Wade Allen.

2. STINKFIST GROUP(Distance=47 feet, 12-5-97) Aaron Judge (cajudg00@pop.uky.edu) , Jeff Bowers, Jeff Metze Email: jpmetz00@pop.uky.edu , Paul Upton.

3. ENIGMA GROUP (Distance=45.5 feet, 12-10-97) Clain Hendrix, Kevin Mefford, Rodney White Email: rawhit0@pop.uky.edu , James Wilson.

4. SLOWPOKES GROUP (Distance=42 feet, 12-9-97) Mun Yeong Choy (mychoy0@mik.uky.edu) , Jin Churn Chong, Wei Ping Lor, Tai Chan.

5. L^2 DESIGN GROUP(Distance=39 feet, 12-5-97) John Lemaster johlemaster@uky.campus.mci.net , Marc Leach.

6. SCHMITT TRIGGERED(Distance=21.5 feet, 12-10-97) Corey Clark clclar1@pop.uky.edu , Amy Bush acbush0@ewl.uky.edu , Shawn O'Conner, Craig Carpenter.

7. CARR'S GROUP(Distance=13.5 feet, 12-5-97) Christopher Carr alpha7@uky.campus.mci.net , Bamidele Ali, Joseph Harbeson, Darren Boyd, Rami Alkabra.

8. ABSENT MINDED GROUP(Distance=11, 12-8-97) Brian Cottongim (brcott0@ewl.uky.edu) , Chris Hughes Email: cahugh@uky.campus.mci.net , Patrick Baisden, Jeff Leuderalbert.

FINAL CONTEST RESULTS

FIRST PLACE: Two teams, ENIGMA and W.A.R.N. tied for first place by successively transmitting 237 feet which is the full length of the contest location. Both teams used laser diodes for transmitters.

SECOND PLACE: SLOWPOKES attained the farthest distance with an IR LED transmitter.

THIRD PLACE:STINKFIST.

OTHER RANKING (4)L^2 DESIGN, (5) CARR'S GROUP, (6) ABSENTMINDED, (7) SCHMITT TRIGGERED.

SPECIAL HONORS

Best Electronic Design - ENIGMA and W.A.R.N. Both teams had designs that significantly differed from the baseline designs provided to the class.

Best Circuit Construction - SCHMITT TRIGGERED This team had the most compact and rugged circuit construction.

Best Optical Design - W.A.R.N. and L^2 DESIGN Both teams used reflective lenses on their receivers.

Best Package Design - CARR'S GROUP This team had the most innovative packaging for their light gun and receiver.



FINAL PROJECT and PHOTOS:

Slow Pokes. (BEST WEB PAGE AWARD)

Report
Photo: Left to Right, MunY. Choy, Thye H. Chan, Jin C. Chong, Wei P. Lor.

Stinkfist

Report
Photo: Left to Right, Jeff Metze, Jeff Bowers, Paul Upton, Aaron Judge.

W.AR.N.

Report
Photo: Left to Right, Matt Reed, Mark Nolan, Wade Allen, John Writt.

Enigma

Report
Photo: Left to Right, Clain Hendrix, Kevin Mefford, Rodney White, James Wilson.

Carr's Group

Report
Photo: Left to Right, Rami Alkabra, Bamidele Ali, Joeseph Harbeson, Christopher Carr, Darren Boyd.

Absent Minded

Report
Photo: Left to Right, Patrick Baisden, Brian Cottongim, Jeff Leuderalbert, Chris Hughes.

Schmitt Triggered

Report
Photo: Left to Right, Shawn O'Conner, Corey Clark, Amy Bush, Craig W. Carpenter.

L^2 Design

Report
Photo: Left to Right, Mark Leach, John Lemaster.

CONTEST PAIRING

1st Level Final Four Championship Winner
W.A.R.N. W.A.R.N W.A.R.N W.A.R.N

and

ENIGMA

tied at 237 feet or the full length of the Civil Engr. And Anderson Hall Basement Hallway.

ABSENT MINDED
STINKFIST SLOWPOKES
CARR'S GROUP
ENIGMA> STINKFIST ENIGMA
SCHMITT TRIGGERED
SLOWPOKES ENIGMA
L^2 DESIGN


2nd Level Elimination 6th place 5th place
ABSENT MINDED L^2 DESIGN L^2 DESIGN
L^2 DESIGN
SCHMITT TRIGGERED CARR
CARR




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