Making a tiny GPS position recorder
Where in the World

© Lead Image © Zoya Fedorov, 123RF.com
Design and construct a battery-powered GPS receiver and recorder in a compact package, with firmware and a Linux-based GUI application for visualizing the data recorded.
A variety of solutions are available for tracking the location of things, such as locating "lost" items (e.g., smart dog collars) or locating your luggage (e.g., Apple AirTags). All these devices have to balance functionality, size, weight, and time of battery life (rechargeable or otherwise). A mobile phone makes a pretty good location device, because it has a GPS receiver and a radio transmitter. However, they are relatively large, are expensive, have unnecessary components (e.g., displays), and rely on a cellular network that might not be available in remote areas.
Apple AirTags rely on Bluetooth communication with other Apple devices in the vicinity to provide position information and relay that data to iCloud, which the user can access with the Find My app. This useful function allows the tags to be very small and operate from a small button cell battery. The drawback to this method is its reliance on other devices and, again, the presence of a cell network.
The device presented here is completely autonomous; the size of a matchbox, weighing less than 50g (<2oz), and has its own GPS receiver, a LiPo battery providing several days of operation, and flash memory to store the acquired GPS data. Because GPS coverage is worldwide in its various forms, no other infrastructure is required for operation.
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