GPS Terminology You Need To Know

GPS is a pretty common part of our modern lexicon, but unless you're a tech guru you may not know what all the terminology means and how it affects our everyday lives. Following are some of the basics to help give you a working knowledge of all things GPS.

GPS - Global Positioning System:  A network of satellites and ground stations that "talk" to each other to map every square inch of planet Earth.

Longitude:  One of the measurements GPS units fixes; the location on the world map east or west of the north-south Prime Meridian.

Latitude:  The other measurements GPS units calculate; the location on the world map north or south of the equator.

Trilateration:  The method by which GPS satellites and their ground stations calculate a fixed point on the map. The method uses two or more known points and the difference in distance between the subject and those known reference points.

Assisted GPS:  A type of technology that uses some type of assistance serve to cut down the time to pinpoint a GPS location. Assisted GPS is most closely tied to cell phones because the Federal Communications Commission wanted emergency dispatchers to be able to quickly locate a cell phone if someone was calling 911 for emergency help from a cell phone.

Line of Sight:  In order for GPS systems to work properly, the GPS receiver must have a clear line of sight to at least four satellites in the Global Positioning System's network of 24 satellites. In areas where this is difficult (i.e. indoors or in urban situations where the person might be surrounded by tall buildings) is where the importance of Assisted GPS comes into play.

Geocaching:  A type of location-based game similar to a treasure hunt in which players use personal, handheld GPS units to locate "treasures", typically nothing of real value beyond the fun experience of finding it.

GPS Machine Guidance:  A type of GPS used in agricultural operations to help farmers manage their crops more efficiently and produce yield maps.

Differential GPS:  A highly accurate form of global positioning that utilizes the readings from several stationary GPS receivers to figure out the difference between an object's known position and the position being indicated by a GPS signal. The difference is broadcast as an FM signal so that GPS receivers can calculate the more accurate location.

GPS Tracking:  Can be used to track vehicles, people, even pets. Periodic recordings of where the tracked object is provide a track of their movements.

Geodashing :  A worldwide game in which players try to reach as many previously selected GPS map points as possible within a set time limit. The team that reaches the most points, known as waypoints or dashpoints, wins the game.

WAAS:  Wide Area Augmentation System; a program initiated by the Federal Aviation Administration to ensure the accuracy of GPS data coming from the network of GPS satellites.

If you really want to get into the specifics of GPS terminology, check out http://www.rbf.com/cgcc/glossary.htm for a rather extensive and technical glossary.