• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

The Global Positioning System.

Extracts from this document...

Introduction

The Global Positioning System Anna Reoch The global positioning system (GPS) is a satellite-based navigation system, consisting of a network of 24 orbiting satellites travelling on six different orbital paths. These satellites, referred to as NAVSTAR satellites, are constantly moving, making two complete orbits around earth per day. The first GPS satellite was launched in February, 1978. Satellites now weight approximately 1 tonne, and are about 5 metres across with extended solar panels. GPS needs at least 24 satellites to provide full coverage of every point on the earth, all the time. To calculate one position on the earth, at least 3 satellites are needed. Currently, there are 28 working GPS satellites, out of roughly 750 currently in miliary, civilian and commercial use. GPS satellites, quite simply, broadcast data - each satellite knows two things: its exact location in obit, and exactly what time it is. It knows its position within a few feet, whilst moving a t 17 000 miles per hour, and knows the time within approximately 100 picoseconds (1 trillion picoseconds to a second). The satellite signal also contains a 'psuedo-random code' - its identification, ephemeris and almanac data. ...read more.

Middle

A process known as Differential GPS (DGPS) employs a second receiver at a fixed location to compute corrections to the GPS satellite measurements. A number of free and subscription services provide these DGPS corrections, which will considerably improve accuracy. Without the use of DGPS however, accuracy has been measured with a global average error less than 13m. It was war that was the first to bring GPS to the popular imagination: initially in the Gulf War, and then this year, in Iraq. The US military uses its GPS to deliver bombs, missiles and even individual artillery shells to targes with complete exactitude. This is actually just an extension of the original intention of GPS - to provide guidance and position information to the military. Now however, the commercial and civilian uses of GPS have outstripped the miliary uses. In 10 years, GPS has proved itself an indispensable tool. It's predicted that at the end of 2003, as many GPS devices of all kinds will be produced as in the previous 25 years that the satellites have been in orbit, and that in 2004 the number of devices will double again. Indeed, GPS is proving itself a genuinely transformational technology. ...read more.

Conclusion

Anything of value, that has the potential to be stolen, could be relocated through GPS - everything will know its location, and be able to report it. Insurance companies would be able to sell auto insurance based on how you actually use your car. They then review the GPS information on where you've driven, how far, how fast, and can bill you for the risks that you're taking. A trial has already been performed in Texas using such a system. Indeed, commercial companies are now using GPS for ultimate knowledge - knowing exactly where their units are, and what they are doing, in the mould somewhat, of Big Brother. Big Brother-esque again, is the fitting of GPS chips into mobile phones. By the end of 2005, all mobile phones sold in the US must be able to report their location. The GPS phone will know where it is and be able to report that information, if it is stolen, in an emergency, if you are lost. Further GPS research can only further the dominance of this technology, providing a future with greater awareness, greater knowledge, openness and even wider communication, making the world once more a smaller place. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Computer Science section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Computer Science essays

  1. Programming Techniques

    The while loop iterates on a true Boolean condition whereas in a repeat..until, it iterates on a false boolean condition (3) The repeat..until loop will execute at least once whereas the while loop may not execute at all The for loop (For...next loop)

  2. Free essay

    Setting up and E-Commerce Site

    competitive rate * E-Commerce setup, including customized shopping cart * Content writing and management * Programming customized to your needs * Search Engine Optimization (SEO) for Search Engine ranking Search engine optimisation as I said in the task one of this assignment is a key consideration that needs to be

  1. overview of GPS

    The orbital radius is approximately 26,600 km (i.e., distance from satellite to centre of mass of the earth)' Corin Gareth Pearce Figure1 http://www.ncgia.ucsb.edu/education/curricula/giscc/units/u017/figures/figure02.gif The figure on the next page shows how the three segments of GPS work together to give information to the user.

  2. AQA Computing CPT3

    stop, it will also stop the pay display (variable - totalToPay) to stop calculating, and provide the final amount of petrol that the customer has to pay for the current transaction, this is calculated according to the price per litre (variable - pricePerLitre)

  1. Smart Card System

    The sequence of sending a data packet transmission is requested be an end node and controlled by the repeater. When a data packet transmission is about to occur: If an end node has a data packet ready to send, it transmits either a Request_Normal or Request_high control signal.

  2. Definition-nature of the problem solved - Car Mechanic business

    Customers who don't want to talk to a mechanic through about five other people can just have face-to-face meetings to discuss the problem and make the decisions around that. It's a trust thing, I don't think they mind the paper-based approach but they would probably prefer it to be a

  1. Flexible Architectures in Communication Security Application

    Secret-key ciphers have the advantage of running as much as 1000 times faster than comparable public-key ciphers [30]. To maximize security and performance, most secure protocols use both forms of cryptography. Public key encryption is used at the start of a session to authenticate communicating parties and to securely distribute a shared secret key.

  2. ICT Coursework - Big M Cinemas

    When designing the web-based system I could have used Microsoft Word, PowerPoint or many more. I needed these applications to be easy to use, change and alter. It should be easy to access different pages on the site. Inserting hyperlinks to websites and files should be easy to use.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work