Handheld Wireless GPS Tracking Device

1. Handheld Wireless GPS Tracking Device Senior Design EEL 4914C : UWF, Fall 2006

2. Team • Doug Cumbie • Developed GPS Module and Wireless Transceiver Module. Assisted in development of LCD software interface. • Jonathon Bean • Developed User-Interface Module, Power Supply Module, and assisted with LCD software/hardware interface. PCB Design and assembly. • Faculty Mentor: Dr. Thomas Gilbar

3. Abstract The enhanced awareness that Global Positioning Systems (GPS) provide has revolutionized the way we interact with our surroundings. Many industries today, primarily in aviation, depend upon the latitude, longitude, and altitude information that GPS provides. Commercially, GPS has become increasing popular for use in vehicles and handheld units. An enhancement to a GPS device would allow for the ability to not only track your own position, but the position of other remote devices. By utilizing wireless communication technology, the position information obtained from a GPS may be relayed to other devices for tracking and increased awareness of other remote units.

4. Introduction • Main Goal: Develop a GPS Device with the added feature of remote position tracking/sharing. • Intended Users: Various user groups • Hikers • Military • Disaster Relief – Rescue workers • Limitations • GPS requirement for outdoor, sky-visible condition • Limited range of wireless transceiver

5. Design Requirements • Main Design Objectives • Provide geographical present position information • Provide ability to transmit present position information to a remote unit either automatically or on-command • Provide ability to receive a remote unit’s position information • Present a graphical presentation of remote unit’s position relative to self position • Provide a predefined-message sending capability • Present all information on a graphical liquid crystal display (LCD) • Provide a minimal user-interface for simple use • Package components in a compact case

6. Design Requirements cont… • Constraints • Time • Product Selection and Cost • Standards • NMEA 0183 Interface Standard for GPS Data Retrieval • UART for Module Communications • FCC Approved Radio Transmission

7. End Product Description • The Handheld Wireless GPS Tracking Device is a product that provides the user with the ability to obtain one’s geographical position in the form of latitude, longitude, and altitude and wirelessly share this data with another similar device. The battery-powered device is packaged in a compact case for easy operation and portable use. The user interface consists of a graphical display and four buttons used for paging through various informative screens. The graphic LCD provides information to the user that consists of current present position, numeric position of the remote unit, graphical position of the remote unit, and a message sending/receiving capability. The device utilizes a wireless transceiver that is capable of transmitting the user’s position information up to 14 miles line-of-sight. The Handheld Wireless GPS Tracking Device is useful for many scenarios that require knowledge of another person or group’s location.

8. Technical Approach • Modularized Design • Microprocessor Module • GPS Receiver Module • Wireless Transceiver Module • User Interface Module • LCD and Pushbuttons Interface • Power Supply Module • System Software Modules • Main • GPS • Radio • LCD

9. Component Parts Breakdown

10. Microprocessor Module • Runs Main Loop • Initializes all Modules • UART Parsing • Button Handling • LCD Refresh • LCD Screen Transitions • User Message Sending

11. GPS Receiver Module • Initializes GPS Receiver • NMEA Parser • Updates Present Position Structure (Latitude, Longitude, Altitude, Heading, and Speed) • Slant Range and Bearing to Remote Device Calculations • Formats Position Message for Sending

12. Radio Software Module • Initializes Wireless Transceiver • Sends Message Data • Receives Message Data • Parses Received Position or User Messages • Stores Parsed Position Data in Remote Position Structure • Message Structure Format: Comma-Delimited ASCII Packets

13. User Interface Module • Pushbutton Interface • Power Switch: Double-Pole Double-Throw • Four User Pushbuttons

14. User Interface Module cont… • LCD Interface • Initializes MOD5213 Queued Serial Peripheral Interface (QSPI) • Initializes LCD Device • Provides Software API for Character Writing and Graphical Drawing to the Display • Format 48x84 pixel display into 6 row x 14 column character map

15. User Interface Module cont…

16. Graphical Tracking “X” represents remote unit position relative to self User’s heading is referenced toward top of screen, remote unit is referenced from user’s heading. 2 Miles Wide by 0.878 Miles High Maximum Distance (1 mile = 20.5 pixels) Range (miles) and Bearing (degrees) User Interface Module cont…

17. Power Supply Module • Two DC Voltage Supplies • 3.3VDC Regulated for MOD5213 and LCD • 5.0VDC Regulated for GPS and Radio Modem • Double-Pole Double-Throw used for Power Switch • Transient Suppression Circuits for Protection • Battery Life (max calculated): • 20.697 hrs for 3.3V Supply • 9.69 hrs for 5.0V Supply • Approximately 9 hour overall battery lifetime

18. Full System Schematic

19. Power Supply Schematic

20. Printed Circuit Board Design

21. Printed Circuit Board Assembly

22. Testing Approach • Validate each individual module independently for proper operation • Full System Tests • Validate all modules operate as expected • Radio transmission between units • GPS Position Fix • LCD Updates • Pushbutton Events

23. Budget

24. Compact Case Design with Simple User Interface GPS Position Information Remote Device Position Tracking Predefined Message Sending/Receiving Final Product Results -Handheld Wireless GPS Tracking Device