Verified Document

Global Positioning System Term Paper

Global Positioning System GPS is a navigation system that gives our exact location on earth at any time and anywhere. It is a high precision tracking system that provides accurate location coordinates mapping even the remotest of locations. Though it was initially designed, developed and controlled by the U.S. department of defense for its military purposes, it soon became available for the civil users worldwide. This navigation system covers the entire surface on earth using 24 satellites (and 3 additional) that orbit around it at a height of 11,000 nautical miles. [The Aerospace Corporation]. Ground stations based in five different locations on earth receive signals transmitted by these satellites and send data, which are used to monitor and control the satellites. Considered a revolutionary breakthrough in the field of navigation, this technology is finding newer applications everyday. A brief overview would provide us a better insight into the subject.

Global Positioning System

GPS makes use of high frequency radio wave transmitters stationed in space making it possible to cover the entire globe accurately. Locations can be tracked to precision up to a height of 300 ft above earth. The GPS system has three different segments namely the space segment, ground-based control stations and the user segment. As discussed above the space segment is composed of 24 satellites moving in fixed orbits taking 12 hours to complete one full circle across the earth. The GPS communication system with all the 24 satellites was completed in 1994. The orbits of these satellites are arranged such that at any point of time at least 4 of them are in visual range from any point on earth. [The Aerospace Corporation]

GPS Control Stations

The control stations are based in strategic locations across the globe. There are a total of 5 such control stations that are based in Hawaii, Kwajalein Island in the South Pacific Ocean; Schriever Air force base in Colorado Springs, the Diego Garcia Island in the Indian...

The Schriever airbase station serves as the central control station. These stations perform the clock corrections for all the GPS satellites and also upload the ephemeris data as and when required. [Peter H. Dana]
GPS Receivers

The GPS user segment is nothing but receivers or gadgets that are equipped to receive the signals from the satellite. It is the receivers that perform the calculations to deduce the location. To do this the receiver must locate four of the GPS satellites and find out the distance from them. Then using a geometrical principle called trilateration the location is calculated. Trilateration is similar to the triangulation function of location determination except that it does not take into account the angle factor. Using a minimum of three reference points (satellites locations) and the distance between each reference point to the affixed point, it is possible to identify the location of the fixed point anywhere on earth. Thus by knowing the position of three satellites (4 satellites for three dimensional mapping) and the distance to them, GPS receivers can locate themselves on earth. The positions of the satellite at any given time is easily known because of their standard orbits. Every GPS receiver also has an almanac, which stores the predicted path of the satellites. [Marshall Brain]

GPS Satellites have highly accurate atomic clocks that can differentiate up to billionths of a second. To find the distance from the reference points (satellites) the receiver calculates the time taken for the radio waves to travel from the satellites to itself. This is done by means of a simple calibration. The satellite generates and transmits a particular digital pattern that the receiver can also generate. However, there is a time lag associated with the satellite's signal pattern compared with the similar pattern generated by the receiver. The receiver measures the time lag and multiplying it with the speed of light obtains the distance from…

Sources used in this document:
Bibliography

1) The Aerospace Corporation, "GPS Primer', Accessed on 6th December 2004, http://www.aero.org/publications/GPSPRIMER/

2) Peter H. Dana, "Global Positioning System Overview," Accessed on 6th December 2004,

http://www.colorado.edu/geography/gcraft/notes/gps/gps_f.html

3) Eurofix, 'PRN Codes', Accessed on December 7th 2004, http://www.eurofix.tudelft.nl/prncode.htm
4) Chris Rizos, "General Applications Of GPS," Accessed on 6th December 2004, http://www.gmat.unsw.edu.au/snap/gps/gps_survey/chap2/231.htm#air_applics
http://electronics.howstuffworks.com/gps1.htm
Cite this Document:
Copy Bibliography Citation

Related Documents

GPS Assessing Global Positioning Systems
Words: 2109 Length: 7 Document Type: Thesis

While this presents enterprises with unequalled levels of potential productivity gains, it also presents security and privacy challenges as well. In the context of cyber foraging, the issues of ethicacy and opt-in meet head-on, as the use of servers to cache locations and define locational preferences and habits of consumers. For these privacy reasons and the untested nature of location-aware advertising services, it is anticipated that GPS-enabled networks such

History and Theory of Global Positioning Satellites
Words: 1490 Length: 5 Document Type: Term Paper

Global Positioning Satellites The History of Global Positioning Satellites The First Global Positioning Satellite Transmission Functions of the Global Positioning Satellites Reception of Information from Global Positioning Satellites Advantages of the Global Positioning Satellites System Introduction to the Global Positioning Satellites As the name suggests, the global positioning satellite system is based on satellites. It is a navigational system that comprises of a complex arrangement of satellites that orbit round the earth. Twenty-four in all, these

Global Technological Advancements on the
Words: 6670 Length: 23 Document Type: Term Paper

However, they remind us of the author Lall (2000), who declares that before companies or farms can use and derive the benefits of the technology, they need to learn and develop new skills. Beyond the capacity of adopting new techniques, developing countries also need the capacity to invent and adapt new technologies. Poor countries need to foster their own creativity to use both local and global knowledge and science

Next Generation Air Transportation System
Words: 2879 Length: 8 Document Type: Term Paper

Global Position System (GPS) System Wide Information Management (SWIM) Advanced data Communication Next Network Enabled Weather The NAS Voice Switch Structural design of new aircrafts In this paper, we look into the new technological development in the air transport system such as GPS in air traffic management, airport infrastructure and proactive safety management. In details the paper discusses the user of specific situation awareness including a new broadband information network, weather observation, prediction and impacts; security,

Wally Wizard, the Manager of Global Positioning
Words: 1057 Length: 3 Document Type: Essay

Wally Wizard, the manager of Global Positioning Navigator System (GPNS) at Behemoth Motor Corporation (BMC), have two alternatives to manufacture GPNS; to make in-house or outsourced to a Chinese company, Far East Enterprises (FEE). So in order to make a decision, cost vs. benefit analysis for these alternatives will be determined to find out the per unit cost of each alternatives, and then better option will be selected. So for

Environmental Systems in the Past
Words: 12463 Length: 45 Document Type: Capstone Project

Although the research tools provided by the ISO 14001 framework are both qualitative and quantitative, this approach is consistent with the guidance provided by Neuman (2003) who points out that, "Both qualitative and quantitative research use several specific research techniques (e.g., survey, interview, and historical analysis), yet there is much overlap between the type of data and the style of research. Most qualitative-style researchers examine qualitative data and vice

Sign Up for Unlimited Study Help

Our semester plans gives you unlimited, unrestricted access to our entire library of resources —writing tools, guides, example essays, tutorials, class notes, and more.

Get Started Now