Global positioning systems, or GPS units, have become commonplace in modern society. As is true with any device that can record and store data, these devices can become a source of evidence in civil and criminal cases [1].
In using GPS data as evidence, it is important to understand what impacts the accuracy of the data these devices produce as well as the potential for errors in analyzing the data. While global positioning is best known for its use in navigation, it is also used to pinpoint and record precise locations in land surveying, and the GPS system is also used for time and frequency purposes in telecommunication systems because of its extremely accurate onboard clocks located in the satellites themselves. “GPS satellites have very precise clocks that tell time to within 40 nanoseconds or 40 billionths (0.000000040) of a second.” GPS capability shows up in some unexpected places, and there are devices and programs that can perform GPS functionality without being a dedicated GPS unit [2].
Companies use GPS devices to track their trucks and the employees driving them, and GPS units are in many rental cars both for navigation and for the recovery of lost and stolen vehicles. The social media website Twitter can track your location, and applications for phones, such as Facebook Places, can send updates to your networking sites with information about where you are at the moment. Using your smartphone, you can also tag other’s locations for posting to Facebook. The tracking system is generally used in cars, planes, and pets, as well as for children to keep track of where they are [3].
In general manner, the GPS system consists of three parts or segments that can be broken down
into the space segment, the ground segment, and the user segment. The explanation of each segment is interpreted as follows [4]:
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Space Segment: The space segment is the part of the system that is made up of the GPS satellites that are in geosynchronous orbit around the earth.
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Ground Segment: The ground segment is the part of the system that has the master control station operated by the Air Force, and both ground antennas and monitoring stations. The master control station is where the Air Force manages the satellite system. The ground antennas collect telemetry information from the satellites and also send commands and data up to the satellites for accuracy corrections.
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User Segment: The user segment consists of the devices that actually receive and use the data provided by the GPS satellites to perform navigation, such as handheld, marine, aviation, and automotive units. Figure 1 shows the GPS system and its various segments.
Many years ago, many cases of missing children between ages 14 and 17 years are reported. Parents always worry about the possibility of kidnapping or the loss of their children. With the development of technology, the emergence of microcontrollers, and the emergence of smart navigation and tracking systems on Google Maps, there has become a necessity to solve the mentioned problem. In this work, we will design a small, inexpensive device that can be placed in a child's neck or bag to be tracked via Google Maps. In addition, this device can be used to track pets or put in vehicles and bikes to track them and thus know where they are.