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									Infrared Keyless Entry                                                   Page 1 of 7

                                 Test specification for

                   Automotive Infrared Keyless Entry System

                                    Submitted to:
                               Professor Joseph Picone
                             ECE 4512: Senior Design I
                  Departments of Electrical and Computer Engineering
                             Mississippi State University
                         Mississippi State, Mississippi 39762

                                    March 2, 2001

                                        Submitted by:
                      Adria Jones, Kenny Reynolds, Ray Smith
                            Advisor: Dr. Raymond Winton
                  Department of Electrical and Computer Engineering
                              Mississippi State University
                                       Box 9571
                              Mississippi State, MS 39762
                        Tel: 662-325-2095, Fax: 662-325-8546
                     Email: {adj1, rkr1, rgs1}

ECE 4512                                                               March 2, 2001
Infrared Keyless Entry                                                            Page 2 of 7

                          EXECUTIVE SUMMARY
Wireless communication has become more and more common throughout the
technological world. One form of wireless communication is infrared (IR) data
transfer. It has proven to be a very versatile and reliable medium for control and
communication devices. It has been used in CPU’s for some time and cell phone
technology is picking up on the trend as well. We propose to design an Infrared
Keyless Entry system (IKE) for automobiles.

Automotive companies have used infrared keyless entry in the past few years.
However, the majority of cars use Radio Frequency Keyless Entry (RFKE). RFKE
systems send signals from the transmitter to the receiver. However, the receiver
does not send back a signal informing the user that the signal was received. RF
signals are sometimes blocked or interfered with due to a variety of elements as
well. RF devices also have to meet certain FCC rules and regulations where IR
does not. IR will be a cheap, easy, and efficient means of keyless entry for

IR technology is very versatile. With IR, consumers can communicate by laptop,
cell phone, palm tops, etc. The IKE system we will design will consist of two parts:
the transmitter, which creates and sends the encoded signal and the receiver, which
receives and decodes the signal then performs an operation. So, the IR transmitter
and receiver system we plan to design will have to be flexible. There are many
requirements that must be met for this project to be a success. The transmitter and
the receiver must be small, lightweight, and durable. They must consume as little
power as possible and no more than 100mA of current apiece. The receiver will run
off of power from the vehicle’s battery, and the transmitter will run off of a 6 V
battery. The range of the IR keyless entry will be 20 feet in normal daylight
conditions with a viewing path angle of 30-degrees. To be an efficient design, our
project will have to meet all of our stated design objectives.

To encode and decode the infrared signals, we will need a micro-controller. The
transmitter will send encrypted infrared signals to the receiver. The receiver will
then be able to decrypt the signal and perform the operation of opening the door
locks on the automobile.

1.Flexibility of IKE can be expanded to allow integration with personal laptops, cell
   phones, or any other type of IR device. It can also be used to perform various
   operations on an automobile ranging from rolling down the windows to starting
   the engine. INTRODUCTION

ECE 4512                                                                       March 2, 2001
Infrared Keyless Entry                                                              Page 3 of 7

The goal of this project is to design and implement a low cost infrared keyless entry
system for a vehicle. By incorporating infrared technology, the system will allow
existing communication devices with IrDA compliant ports to interact with the
automobile, thus giving the user alternate access to the vehicle. Design approaches
will incorporate equipment that will allow circuit simulation, projected waveforms
for distance, voltage, and frequency, C++ coding, and overall performance.

The design constraints for our project are:

      1.IrDA Compliancy: We will obtain an infrared transmission speed of 9.6

      2. Security Coding: Signals transceived between the units will have to be
         digitized and encoded in a manner to ensure vehicle security. Third-party
         devices such as palmtops and PDAs will have specialized software to
         provide proper encryption and data transmission between the units.

      3. Range: The transmitter will have a transmission range of no less than 20
         feet during normal daylight conditions.

      4. Power Supply: The power supplies for the devices will be simulated with
         circuit simulation software to ensure that the units will consume no more
         than the specified design requirements.

      5. IR Signal Transcieving: Viewing angle path of transmission and reception
         will be no less than 30 degrees. The unit will also be able to transmit
         signals through the windows of the vehicle. The units must also be tested
         during normal daylight conditions to ensure that the units will operate

      6. Endurance Testing: Endurance testing will be necessary to ensure that the
         receiver will be capable of withstanding the rigors of automobile travel.
         The transmitter will be required to endure the ruggedness of the external
         travel and mobility of the driver while out of the vehicle.

Testing each of these requirements will ensure that the keyless entry system will
operate properly and meet all of the specified design constraints. These design
constraints will enable IKE to allow alternate entry to the automobile.

ECE 4512                                                                      March 2, 2001
Infrared Keyless Entry                                                                          Page 4 of 7


Testing each of the components of our system will be done with a variety of
hardware and software tools. Several preliminary tests will be made to ensure that
each component of the system works. We will be constructing prototypes of each
component to ensure that each component works and interfaces properly to the rest
of the system.

    Constraints          PSPICE EWB* Oscilloscope             C++ Altera Max Performance
                                                             Coding Plux II      Test

 IrDA Compliancy                     X            X             X           X
   Programmable                      X            X             X           X
    Logic Device
  Security Coding                                               X           X              X
       Range                                      X                                        X
   Power Supply            X                                                X              X
  IR Transmission          X                      X
    IR Receiver            X                      X
     IR Signal                                                                             X
 System Durability                                                                         X
Table 1. A summary of the proposed test specifications to evaluate the Infrared Keyless Entry
*Electronics Workbench


Pspice software will be used to simulate and develop the power supplies for both the
transmitter and receiver. The transceiver circuit will be designed and simulated to
operate on a 3 V source. The circuits will also be tested at other various voltage
conditions that might occur. Pspice will also be used to test and simulate the circuits
of the transmitter and receiver.

2.2Electronic Workbench

ECE 4512                                                                                    March 2, 2001
Infrared Keyless Entry                                                            Page 5 of 7

The logic capabilities of Electronics Workbench software will be used to simulate
the digital coding of the infrared signal. In order to maintain proper IrDA 1.1
compliance, this digital signal must operate at 9600 bps. EWB will be used to
simulate this digital signal transmission as well as simulate the circuits of the
transmitter and receiver.


An oscilloscope will be used along with other compatible devices, such as a
function generator and frequency analyzers, to simulate and analyze IrDA
compliancy, range, IR signal transceiving, and daylight signal cancellation. It will
be used to determine appropriate operating frequencies for the devices. It will also
be used to record the waveforms emitted and received. These waveforms will be
compared to calculate the signal to noise ratio (snr).

2.4C++ Coding

Microsoft Visual Studio C++ will be used as the primary language for digital IR
signal encryption. Signal encryption will be necessary to maintain proper security
of the system.

2.5.Altera Max II

The Programmable Logic Devices (PLD's) used to transceive the IR signal will be
simulated using Altera Max Plus II. Boolean equations used within the PLDs will
be created for signal encryption techniques. The software will be used to provide
all possible combinations of signal input conditions. The outputs will be given in
the form of a timing diagram and then translated to a binary chart.

2.6.Performance Test

Various performance tests will be performed to the transmitter and receiver to
ensure correct functionality. Such tests will ensure proper security coding, effective
range of the IR signal transmission under normal daylight conditions, and power
consumption of the components. Endurance testing will also be used to determine
and ensure the durability of the transmitter and receiver. A wide temperature range
test and vibration tests will also be conducted to ensure that the receiver unit is
capable of handling the conditions of a vehicle in travel. The transmitter device will
be durable enough to withstand a drop from several feet.

ECE 4512                                                                       March 2, 2001
Infrared Keyless Entry                                                           Page 6 of 7


MicroSim Spice Version 8.0 will be used in the development of circuit diagrams
from our personal computers and Simrall computer labs.

3.2Electronic Workbench

Electronic Workbench will be used in developing circuitry for IKE on our personal
computers and Simrall computer labs.


The Oscilloscopes will be used from the Simrall labs.

3.4C++ Coding

Microsoft Visual Studio C++ and other programming languages will be used on our
personal computers and Simrall labs.

3.5Performance Tests

Performance test will be performed on the prototype in Simrall labs and our
personal vehicles.

3.6 Endurance Tests

Due to the system installation in an automobile, the system must be able to
withstand the harsh environment of a vehicle in motion. Components will be tested
in personal vehicles while in motion.


We would like to thank Dr. Raymond Winton for his continuous support and
feedback during the development of this design project. We would also like to

ECE 4512                                                                      March 2, 2001
Infrared Keyless Entry                                                            Page 7 of 7

thank Dr. Joe Picone for constant input and for numerous documentation templates.
Their guidance and knowledge are greatly appreciated.
[1]     Roy. W. Goody, Microsim Pspice for Windows: A Circuit Simulation
        Primer, 2nd edition, Vol. 1, Prince Hall, Upper Saddle River, NJ, USA, 1998.
[2]     Richard H. Berube, Computer Simulated Experiments for Electric Circuits
        Using Electronics Workbench, Prentice-Hall Career & Technology, USA,
[3]     "Technical Summary of "IrDA DATA" and "IrDA CONTROL",", Infrared Data Association,
        Walnut Creek, California, 2000.

[4]     “How Infrared Motion Detector Components Work,”, Glolab Corporation, 2000

[5]     Weiner, Seymour. “Infrared Radiation,” Encyclopedia Americana, Vol. 15.
        p.169. Grolier Inc.,1994.

[6]     Knutson, Charles D. “Infrared Data Communications with IrDA.” IrDA
        Test and Interoperability Committee. Corvallis, Oregon, 1998.

[7]     "IrDA Data Link Design Guide,", Hewlett Packard,
        Palo Alto, California, 2000.

[8]     Stuart, Robert. “An Introduction to IrDA Control.” IrDA Control: IrDA
        Application Note. Presented at Portable Design East, August 1998.

ECE 4512                                                                     March 2, 2001

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