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GPS Resources from ASAP Motors

Have you ever had to stop to ask for directions? Thanks to the technology of GPS stopping to ask for directions has become a thing of the past. The use of GPS in our daily lives has become a common occurrence that many of us don't even think about. We use GPS technology in our homes, offices and cars. GPS has improved our lives by making us safer and more in tune to the world around us. The technology of GPS started in the 1960s and has taken decades to evolve into the technology we know and use today.

Before the GPS

Before the advent of GPS the way to determine direction and locations was through the use of celestial navigation. One of the first pieces of equipment to use celestial navigation was the sextant. A sextant used celestial observations of the sun, planets and stars. The sextant, which was developed in the beginning of the 19th century, determined position by measuring the height in degrees above the horizon in conjunction with the time. After 1930 electronic navigation technology was developed. This technology included radio navigation and satellite positioning systems used for the military.

How GPS Evolved

The start of the development of GPS began in 1957 when US scientists discovered the ability to track the Soviet satellite Sputnik by determining the changes in the radio frequency of the satellite. Using this knowledge the US Navy developed TRANSIT in 1960. TRANSIT was the first navigational satellite system. The system was used to help guide submarines. In 1967, the US Navy developed Timation, a system that incorporated a synchronized clock located within satellites. By 1978, the United States launched the first four GPS satellites. Before 1983 GPS technology was only available to the military. In 1983, a change to the availability of GPS was prompted after a Korean Airline flight was shot down after it mistakenly flew into Soviet airspace. After the incident, President Regan declared that GPS would be available worldwide not just in the United States. Another change in the availability of GPS came in 2000 when the US military stopped their practice of blurring GPS signals and civilians began demanding GPS technology. By 2005, the first modernized version of a GPS satellite was launched it transmitted a separate signal that civilians could access for free.

How a GPS Works

A global positioning system (GPS) operates by positioning, navigating and timing services. The system is composed of three sections, space navigation, a control section and a user section. GPS satellites transmit signals to equipment called receivers. These receivers require an unobstructed view of the sky. Each GPS satellite contains an atomic clock which is synchronized with the atomic clocks at the US Naval Observatory. A GPS receiver must obtain signals from at least four satellites however, if a fourth satellite is not available, a receiver can work off of three satellites. Each GPS satellite transmits its location and time data. A GPS receiver uses the signals it receives from the satellites to determine the time the signals where sent, in turn the satellite then positions itself corresponding to these times. This data is used to identify the receiver's exact location on earth in relation to the location of the satellites. There are at least twenty-four GPS satellites working at all times.

GPS Uses Today

GPS uses today include applications on Smartphones for personal safety, and personal navigation, entertainment and recreation and enhancing reality. The most common use of GPS for personal safety is OnStar. OnStar uses GPS and vehicle telemetry information to help discover potential emergency situations, diagnose vehicle problems, remotely unlock vehicle doors and assist in locating stolen vehicles. GPS is commonly used for personal navigation. GPS for personal navigation includes maps, turn-by-turn directions, real-time traffic reports and weather updates. Another popular use for GPS is for entertainment and recreation. Geocaching is one form of using GPS for entertainment. Geocaching is an advanced form of scavenger hunting which uses GPS to find geocaches consisting of items for collecting or trading. The use of GPS for recreation includes athletic training. The MyTracks app allows users to plan routes used for running, bicycling and walking. The app also allows the users to record their speed, time and distance traveled. A new use for GPS is enhancing reality. Enhancing reality apps use GPS to reveal information to the user about the physical world around them. The apps use a cell phone's camera to reveal restaurant locations, real estate prices and crime statistics for the area displayed through the cell phone's camera.

GPS Overview

Global Positioning System

GPS Info

Global Positioning Systems Directorate

The Global Positioning System (GPS)


General Information on GPS

Global Positioning System Overview

GPS Tracking: The Future


Improving GPS Accuracy

GPS Goes To War

The Navy and Satellites

GPS Satellite History

GPS Bibliography

Written by: Milan Alcot