How Does GPS work?

Global Positioning System (GPS) is funded by and controlled by the U. S. Department of Defense (DOD).

These GPS satellites circle the Earth every 12 hours and send signal information to earth. According to the DOD, GPS consists of three segments - the satellite constellation, ground control network, and user equipment. Together, these three components provide information to the user equipment (the GPS unit) and the receiver collects and compiles the signals.  Each GPS satellite transmits an accurate position and time signal to formulate the user’s exact location.  Comparing the time a signal was formulated with the time received informs the receiver and helps it to determine distance and exact location, which is displayed on the user’s map.

This is how the system begins to generate a detailed trip planner for the user.

Can a portable GPS be used anywhere?

Today, Portable GPS units can be used virtually anywhere as long as you have a GPS receiver and open access to the earth-orbiting satellites, which inform your unit about where you are at any given time and tell you how to get to a destination. GPS devices are being used today by people on land, water and in the air.

Can new maps be uploaded to personal GPS devices?

New maps can be purchased and downloaded to personal GPS devices. A user can purchase a more detailed area map and have them downloaded to a GPS device by connecting the unit to a computer with a USB cable or by downloading detailed maps via cartridges.