The Global Positioning System or GPS is a system of satellites that was originally started by the United States Department of Defense in the early 1970's. The 24 satellite system became fully operational in 1993 for military navigation and tracking. Today GPS has two different levels of service: Standard Positioning Service (Available to Everyone) and Precise Positioning Service (Available only to the U.S. Armed Forces).
How It Works:
The satellites orbit the earth an altitude of 20,000 km and constantly beam out radio waves that carry a signal to your receiver. Each satellite has four atomic clocks on board that time stamp each radio wave which allows for it to be timed on its way to the receiver. Then it combines the time and how fast the radio wave travels to determine the distance between the satellite and receiver. No matter where you are on earth you will be able to receive a signal from at least 4 satellites. This allows it to use a method called Trilateration to pinpoint your position. Trilateration is where at least three satellite use their distance to the receiver to form overlapping spheres that will show where they intersect.
- Allows for easy travel
- Inexpensive
Cons:
- Requires the use of satellites
- Privacy issues
Future:
In the future GPS will play a large role in the automation of farming by creating self driving tractors. It will also be used to create a system of self driving cars and self flying planes. GPS will eventually eliminate the need and use of radar technology.
Works Cited
Dunbar, Brian. “Global Positioning System History.” NASA, NASA, 5 May 2015, www.nasa.gov/directorates/heo/scan/communications/policy/GPS_History.html.
How Does GPS Work?| Explore, www.physics.org/article-questions.asp?id=55.
www.explainthatstuff.com/howgpsworks.html.
No comments:
Post a Comment