PowerPoint PresentationInfrared Keyless EntryAbstractSlide 4Infrared Keyless Entry SystemTeamDesign Task BreakdownSlide 8Slide 9Slide 10Slide 11Slide 12Slide 13TransmitterSimulation/ResultsReceiver CircuitSlide 17Finished ProductI/O SignalsSlide 20I/O Signals at DistanceSlide 22Ir Problems at DistanceSlide 24Our Problems With IrDACostSlide 27Met RequirementsFuture WorkSlide 30ReferencesInfrared Keyless EntryFinal Presentation Senior Design IINovember 27, 2001Mississippi State UniversityDepartment of Electrical and Computer EngineeringAbstract•Design an interface to allow entry without keys.•Radio Frequency Keyless Entry (RFKE) does not provide flexible interaction between automobiles and external communication devices.•Infrared technology integrated with keyless entry will provide alternate access to automobile.•Devices such as laptops and palm pilots with infrared ports will be able to access the system.Motivation•Allow alternate entry to automobile without keys.•Give flexibility to access multiple components of car.•Ability to program car components with IrDA software.Infrared Keyless Entry SystemTeamAdria Jones, Team LeaderKenny ReynoldsRay SmithDr. Ray Winton,AdvisorDesign Task Breakdown•Kenny Reynolds–Digital Signal Encoding / Decoding–Micro-controller Interface•Adria Jones–Transmitter / Receiver Amplification & Transmission•Ray Smith–IrDA ImplementationKey ComponentsHandheld Ir ReceiverDecodeMicro-ControllerSpecified FunctionAmplificationOptical Signal ReceiverDesign Requirements 1. Functionality:The receiver unit will be able to receive and decode encrypted signals sent from a transmission device via infrared media. After proper decryption, the unit will send a signal to unlock the doors and/or perform some other user-desired operation on another device of the vehicle. 2. Unique Signal Keying:The transmitter will send unique encrypted infrared signals to the receiver. The receiver unit will be able to decrypt codes sent by the infrared remote. The receiver will also be IrDA-1.1 compliant to be able to receive instructions from a third party device, such as a laptop computer or PDA. 3. Power:Power to the receiver unit will be delivered from the vehicle's battery. The system will operate from 10 to 15 Volts DC and consume no more than 100 mA of current. The transmitting unit will operate on a 12V battery and consume no more than 100 mA of current when in operation.Design Requirements 4. Physical Attributes:The receiver unit will be designed to be easily installed within a properly equipped vehicle. The transmitter will have simple buttons for the specified function of the keyless entry system specified by the user. 5. Affordability:Components for both the transmitter and receiver units will not exceed $35.Serial Encoding / Decoding IC’s•Holtek HT-640 serial encoder and HT-648L decoder.•Provide 10 data address lines and 8 control lines. (High, Low, Open)•Built-in RC Oscillator allows for multiple transmission frequencies (~0.15 kHz to ~2.6 kHz).•Codes supplied by PLD (PAL16L8)10 control lines, 8 data lines–Can be tied High, Low, or left open.–3^18 = possible serial combinations.–Code Scanning? At 10 scans/sec -> 1.23 years Example Coding from PIC (f = 100 kHz): A0 A1 A2 A3 A4 A5 A6 A7 A8 A9 A10 D1 D2 D3 D4 D5 D6 D7 D8 0 1 0 1 1 0 1 0 0 1 1 1 0 0 0 0 0 1 1 0 1 0 1 1 0 1 0 0 1 1 1 0 0 0 1 1 0 0 Serial EncodingTransmitter CircuitTransmitterSimulation/ResultsPower Constraint: 100 mAActual: 52mA PeakReceiver CircuitOutputIrDA I/OReceiver CircuitFinished ProductI/O SignalsI/O signals at close range (1 foot).XmitterReceiverI/O SignalsI/O signals at close range (1 foot).XmitterReceiverI/O Signals at DistanceI/O word signals at distance (15 feet).XmitterReceiverI/O Signals at DistanceXmitterReceiverIr Problems at Distance•Ir input signals are shortened.•HT648L Decoder chip requires bits slightly longer to match the operating transmission frequencyof the system.•Possible solution: Tuning the attenuator box?IrDA Access ProgramSoftware interfaces through the PC into the PC/PDA’sIrDA hardware level.Ike.exeOur Problems With IrDASoftware - •PC: Interfacing Hardware Layer of IrDA protocol•Microprocessor Code•Can’t pack enough decryption software into our Microprocessor to thwart random code scanners.Hardware –•Ambient daylight Ir causes severe transmission problems with IrDA.Cost DESIGN COMPONENTS COSTSerial Encoder $2.49Serial Decoder $2.49Microprocessor PIC $5.95IR X-mitter LED’s [2] $0.30IR Receiver LED’s [2] $0.30IrDA Transceiver $3.10Quad OpAmp $1.29SPST Relays $2.18Resistors & Capacitors $1.00Packaging $6.00PCB Fabrication $3.00Battery (12V Alkaline) $0.89TOTAL DESIGN COST $28.99Design Requirement $35DemonstrationMetRequirementsFunctionality Unique Signal KeyingPowerPhysical AttributesAffordabilityFuture Work•Improve the Signal Range!•Finish Debugging IrDA Software•Package Logic Module into a Smaller BoxQUESTIONS?References[1] "Technical Summary of "IrDA DATA" and "IrDA CONTROL", “http://www.irda.org/standards/standards.asp, Infrared Data Association, Walnut Creek, California, 2000. [2] “How Infrared Motion Detector Components Work,” http://glolab.com/pirparts/infrared.html, Glolab Corporation, 2000 [3] Weiner, Seymour. “Infrared Radiation,” Encyclopedia Americana, Vol. 15 . p.169. Grolier Inc., 1994. [4] Knutson, Charles D. “Infrared Data Communications with IrDA.” IrDA Test and Interoperability Committee. Corvallis, Oregon,
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