Senior Design Lab
RFiD Traffic Signal
T.A. Tony Mangogina
I plan to implement the RFID technology for developing a monitoring system that
can be placed at t traffic signals. The system will acquire and log about 6 six
fields of data. Such a system can be used in conjunction with the photographic
method of identifying traffic violators, or it can entirely replace it. The data will be
acquired not only when a vehicle is in violation but at all times. This sort of a
monitoring system can prove to be essential from a security point of view. A
system very similar to this one has already been implanted and is enforced in
certain parts of the Middle East. The government of Illinois also is rallying for
such a system to be implemented.
• Better monitoring, with use of RFID technology
• Higher accuracy than the photograph method.
• Traffic flow monitoring, and individual vehicle monitoring.
• Fully automated, no human involvement.
• Capable of storing 5 to 6 fields of data.
• Can support multiple sensors, one for each lane.
• Can incorporate additional memory chips for large amounts of data.
• Easy viewing with LCD screen.
II. Block Diagram.
PIC Speed Detector
The antenna will be embedded on the surface of the road, and possibly covered
by a fiberglass sheet for protection (In our case since we are building a model,
this will not be necessary.)
Since the vehicles will move one at a time on any given lane, interference will not
be a major problem. I will use 3 lanes to model the traffic; this would simulate a
real world scenario. The antenna I will be using is the pre manufactured 50 ohm
provided by Skyetek.
We will need power supplies to supply the RFID Reader and the Microprocessor
(PIC). The RFID Reader will require around 3.3 – 5 V DC and the PIC will use ab
out 5V DC.
The RFID reader will be placed at a distance near the traffic light pole. It will acqu
ire the signals through the antennae. Its main purpose is to interact with the
passive RFID tags through the antennae and obtain the unique RFID code for
the vehicle. According to the manufacturer it can handle 50 RFID tags per
second so a maximum of 3 tags at a time should not be a problem.
The reader I will be using is the Skyetek M9 module. Since the serial output
given by this is not in TTL voltage levels we will need a MAX233A chip to convert
it so that our microcontroller can read the data.
The Max 233A driver will be used to convert serial out voltages to TTL for use by
the microcontroller. I will be powered by a 5V dc source.
Microprocessor / Memory Management
The PIC microprocessor will be responsible for receiving information from the
RFID reader about the vehicles. It will process the information and determine the
type of vehicle, the license number, etc from its internal memory.
The PIC will be responsible for storing the logged data on the external memory,
and displaying that data on the LCD upon recall.
IV. Testing and Tolerance.
The testing will be conducted at the modular (block) level initially, testing each
block individually. When satisfactory results are shown then the testing will be
conducted at the fully integrated level.
This will altogether be a 4-stage process:
1. Making complete connections between the antennae and the RFID reader.
The testing for this part will be done using a PC and given software, to see if the
tags are being assigned and read correctly. Various angles and speeds (between
the tags and the reader) will be tested in this phase. Since the software for this is
pre developed, this phase should not take too much time.
2. Interfacing between the RFID reader and PIC controller via MAX 233A chip.
Complete circuit connections between these three components will be made.
Testing will be done to verify the data supplied by RFID is conveyed to the PIC.
Connecting the PIC to the PC and reading its internal memory contents will verify
3. Interfacing between PIC and external memory. This could prove to be the most
tedious part of the project. Some data will be stored on the PIC’s internal memory
via the PC and a short program will be written to transfer that data to the external
memory. The memory module can then be hooked to the PC to view the results.
4. Interfacing between the PIC and LCD display. Using the drivers, the PIC will
be connected to the LCD and pre stored data will be displayed. The verification
will come automatically if the test is successful (since the LCD display will flash
the correct data).
When all of the above procedures are complete a decision tree will be
implemented with some human interface for the reading of logged data.
The Rfid reader will be required to read the data from the tags at no less than 2ft
(Hummer H3 has a ground clearance of 1.3ft) of distance. If this proves
unsuccessful a signal amplifier may have to be introduced. The Reader should
be able to pick up data for a car traveling at 120mph at least. The tag is
supposed to have a 2ft spherical radius so data read rate should be faster than
120 mph = 176ft/sec => so time taken to cover a 4 ft distance ~= 0.0226sec =
The manufacturer claims that the Skyetek reader has a data read rate of 40 to 80
kbps(which should be more than sufficient). However, if the testing shows
otherwise, the tag length will have to be fixed in order to facilitate high-speed
V. Cost Analysis and Schedule.
Part Status Manufacturer Description For Price Qty Total
M9 module No Skyetek RFID PIC $1547.70 1 $1547.70
Skyetek No Skyetek Antennea RFID Reader $200.0 1 $200.0
Power No ECS Power ALL $30.0 1 $30.0
Supply 5v Supply
LCD No Toshiba LCD Display $15.0 1 $15.0
Display 16 x
PIC No Microchip PIC ALL $10 1 $10.0
HD 44780 No Toshiba 10 K RES LCD Free 1 Free
MAX233A No MAXIM Driver Microcontrolle $10.0 1 $10.0
ECJ-4YB1C No PAN 10 uf CAP PIC $0.32 2 $0.64
Week Gaurish Kapoor
2/18/09 Work on design review.
2/25/09 Work on design review, Research PIC.
3/4/09 Get parts and work on PIC microcontroller.
3/10/09 Work on PIC microcontroller and external memory.
3/17/09 Integrate RFID receiver and PIC.
3/24/09 Spring break
4/1/09 Integrate PIC and display unit.
4/8/09 Obtain scale model cars and test them.
4/15/09 Mock Demo and testing.
4/22/09 Test and troubleshoot.
4/29/09 Troubleshooting and final presentation.
5/6/09 Present, Demo, and work on final paper.
5/10/09 Work on final paper