Global Positioning System (GPS)

By

Amanda Godwin, Rebecca Provencio, and Erin Rooney

What is GPS?

The Global Positioning System is a system of satellitesthat finds locations anywhere on the Earth.  It can help you find your way when you are lost, and aids in navigation in general.  They are very helpful when you are in search of the nearest gas station, restaurant, banks, etc.  GPS was originally designed by the military.  The idea had been in the works since the 1960s, and in February 1978 the first satellite was launched. (9) A GPS can come in different forms.  Now, you can even use a GPS on your cell phone.  This is called an AGPS and will work more quickly than more expensive GPS's but less accurately. (8)  They can range in price from about $100 to around $2000 depending on how many features you are looking to include in your GPS. (10)

How Does GPS Work?

Global positioning systemsuse a system of satellites to triangulate locations around the world.  There are at least 20 satellites operating at all times.  These satillites send signals to GPS recievers, which is what you would be carrying around with you.  The satellites will all send a signal to your GPS at the same time, some arriving earlier than others.  This is how it figures out distance, based on the time it takes for each signal to arrive at your GPS.  The GPS will then use this information from at least four different satellites to find the location.  The more satellites used, the more accurate it will be. (7)

Activities for the Math Classroom

- Students will be learning how a GPS works. The teacher will provide a layout of the school (an overhead view) projected onto a coordinate plane. The origin will be the teachers’ classroom. The teacher will provide the students with coordinate points that will correspond to other classrooms within the school. Students will be split into groups of 3-4 and they will use what they have learned about how GPS’s work in order to find the coordinate points provided. Once they find the classrooms they students will need to write down whose classroom it is and move on to the next point.

Resources:

1. www.gps.gov
2. http://www.math.tamu.edu/~dallen/physics/gps/gps.htm
3. www.nasm.si.edu/gps/work.html
4. www.youtube.com/watch?v=S_ZnAWyC-M&feature=related
5. www.youtube.com/watch?v=wi_3XwkA8cQ
6.  http://scign.jpl.nasa.gov/learn/gps2.htm
7.  http://www.pocketgpsworld.com/howgpsworks.php
8.  http://www.youtube.com/watch?v=tZXM_g3mqew
9.  http://www.loc.gov/rr/scitech/mysteries/global.html
10.  http://www.articledashboard.com/Article/How-GPS-Came-About/1334642