Global positioning system (gps)

Definition

The global positioning system (GPS) is a satellite-based navigation system that provides accurate location and time information anywhere on Earth. It relies on a network of satellites orbiting the planet, ground control stations, and GPS receivers, allowing users to determine their exact position, speed, and direction of travel.

5 Must Know Facts For Your Next Test

1. GPS was originally developed by the U.S. Department of Defense for military navigation but was made available for civilian use in the 1980s.
2. A minimum of four satellites is needed for accurate positioning; three satellites provide 2D location, while four give 3D location and time accuracy.
3. GPS signals travel at the speed of light and are typically accurate to within 5 meters under open sky conditions.
4. In addition to navigation, GPS is widely used in various applications, including mapping, surveying, disaster relief, and agriculture.
5. The system is maintained by the U.S. government, which provides free access to GPS signals; however, there are also paid services that offer enhanced accuracy.

Review Questions

• How does GPS utilize triangulation to determine a user's location?
  • GPS uses triangulation by measuring the distance from at least three satellites to a receiver. By calculating how long it takes for signals from each satellite to reach the receiver, the system can determine how far away each satellite is. This information allows the GPS to pinpoint the user's location in three-dimensional space through intersecting spheres formed by the distances to the satellites.
• Discuss the transition of GPS from military to civilian applications and its impact on various industries.
  • GPS transitioned from military use to civilian applications in the 1980s when it became available for public access. This shift significantly impacted various industries, such as transportation, agriculture, and telecommunications. With precise navigation and timing capabilities, businesses could improve logistics and efficiency while new technologies emerged that relied on GPS for mapping and location services, transforming how society interacts with technology.
• Evaluate the implications of relying on GPS technology for navigation and its vulnerabilities in real-world scenarios.
  • Relying on GPS for navigation has both benefits and vulnerabilities. While it offers high accuracy and convenience for users in various settings, dependence on this technology can lead to issues when GPS signals are obstructed or jammed. For instance, urban environments with tall buildings may experience signal degradation, and adverse weather can also affect accuracy. Moreover, in critical situations like military operations or emergency response, reliance on GPS could pose risks if systems fail or are compromised by intentional interference.

Related terms

Satellites: Artificial bodies placed in orbit around the Earth that transmit signals to GPS receivers, enabling them to determine location.

Triangulation: A method used by GPS to calculate a user's position by measuring the distance from at least three satellites.

Geolocation: The process of identifying the geographic location of an object, such as a device or person, using technology like GPS.