Loran-C ReceiverGroup MembersBackground: What is Loran-C?Loran-C SignalLoran-C Signal continuedProject PurposeProject FundingTentative BudgetProject ObjectivesOutline of ApproachSubsystems DiagramAntenna Receiver SubsystemAnalog-to-Digital Converter SubsystemFPGA SubsystemProcessor SubsystemRAM SubsystemSerial Interface SubsystemPC SubsystemPowerTasksScheduleDivision of LaborRisks and BackupAbove and BeyondQuestions and CommentsLoran-C ReceiverTeam DeathstarSeptember 7, 2004Capstone Fall 2004Group MembersMatt Anderson (ECE)Chris Birschbach (ECE)Christy Corner (EE)Matt Hayman (EE)Erin Mowbray (ECE)Background: What is Loran-C?Loran-C is a navigation system that was developed by the US Coast Guard. The system is comprised of transmission stations located around the world.The Loran-C signal is transmitted from these stations at specified intervals. By measuring the time delay between transmissions a user can determine their position relative to the towers.Loran-C SignalLoran-C Signal continuedThe Loran-C signal is transmitted on a 100kHz carrier.Project PurposeOur group will design a receiver that will be able to capture and decode the Loran-C signal maintained by the United States Coast Guard. Our system will consist of three main parts: the antenna/receiver, processing unit and personal computer.Project FundingUndergraduate Research Opportunities Program (UROP) Grant.Amount: $1750Tentative BudgetItem Description Estimated PriceProcessor MC68HC912B32 assembled $100.00LCD Display $75.00Additional memory $50.00A to D converter $50.00Antenna Assembly $100.00Receiver Enclosure $100.00Printed Circuit Board $200.00FPGA Xilinx FPGA Evaluation Kit $250.00Filters 3 Butterworth (8th order) $75.00RS-232 Interface $25.00Support Electronics Resistors, Caps, switches, sockets, cables $150.00Power Supply $100.00Student Designed User Manual Weighted Paper, Binding, Printing Costs $150.00Final Project Display Printed Poster for Engineering Expo $100.00Loran C User Handbook $25.00Misc. (Ink Cartridges, Repair parts, Unforeseen Parts needed, additional reference manuals) $200.00 TOTAL: $1,750.00Project ObjectivesCapture a clean copy of the Loran-C signalDetermine Time DelaysConvert to a Latitudinal & Longitudinal coordinates.Outline of ApproachThe system will consist of the following subsystems:Antenna ReceiverAnalog-to-digital converter Motorola 68K processorMemoryFPGASerial Interface PCPowerSubsystems DiagramAntenna/ReceiverFPGA PCRAMA/D ConverterProcessing UnitProcessorAntenna Receiver SubsystemThe antenna/receiver will consist of a loop antenna with a active Butterworth filter to capture and amplify the fundamental signal received by the antenna. This segment of the project serves the main purpose of capturing the Loran-C signal with minimal noise and preparing it for processing.Analog-to-Digital Converter SubsystemThe A/D converter will sample the analog signal.Sampling rate will be 1MHz. The digital data will be sent to the FPGA .FPGA SubsystemThe FPGA has a state machine for detecting the third zero crossing of the Loran-C signal. (Generates an interrupt)It functions as a counter to measure the delay between pulses. It includes an interrupt controller for the processor.Processor SubsystemUpon generation of an interrupt, the processor stores the counter data from the FPGA into RAM. Performs operations on the counter data to determine time delays and stores the delays in RAM.The microcontroller sends the time delay data to the serial interface with the PC.RAM SubsystemHolds the time delay and counter data for processing and transmission.Serial Interface SubsystemThe communication interface between the PC and the processor.Consists of a serial shift register & RS-232 logic level converter.PC SubsystemDisplays the time delays.Performs intensive conversion calculations to convert data into Latitudinal and Longitudinal coordinates. Displays the Latitudinal and Longitudinal coordinates.PowerTransform, rectify, and regulate voltage from standard 120V/60Hz outlet to required DC voltages. (Or purchase power supply)Include portable power sources (battery or car adapter) if time permitsTasks Antenna DesignFilteringPCB designMemory interfaceFPGA designPC programmingPC interfaceA/D interfaceProcessor programmingPowerUsers ManualScheduleDivision of LaborMatt APowerMemory interfaceMicroprocessor ProgrammingChris BPC programmingMicroprocessor programmingUser’s ManualChristy CAntenna/FilteringVerilog DesignUser’s ManualMatt HAntenna/FilteringPCB Microprocessor ProgrammingPC programmingErin MVerilog DesignUser’s ManualPC interfaceRisks and BackupReceiving a clean copy of the signal(Can generate a fake signal)Baud rate generation for PC/processor communicationBuffer overflow (Sample slower)Size and complexity of the state machine.(Can shift tasks from the FPGA to the processor to compensate.)RS-232 Communication on PC(Manually entering data into the conversion program)Above and BeyondIf time permits we shall include a LCD display on our receiver that displays the Loran-C time delays. Portable power sources.Cup HoldersQuestions and