The question you might ask next is; well, how does this global positioning technology work today? There are three main key words which are essential in the understanding of how GPS technologies work in our world today. These are Trilateration, Synchronization, and Time Travel…yes time travel.
To begin, the basic concept of the Global Positioning system consists of having a minimum of 24 operational satellites in orbit at an altitude of about 24,000 km above the Earth and traveling at an orbital speed of around 14,000 km/hour. At any point in time, there are always at least 4 satellites that are “visible” to your receiver (ex. iPhone). The receiver then gets information from at least 3 of these 4 satellites and uses what is called Trilateration to determine your exact position on the surface of the Earth. Trilateration, according to the Encyclopedia Britannica, is a “method of surveying in which the lengths of the sides of a triangle are measured and from this information angles are computed. By constructing a series of triangles adjacent to one another, a surveyor can obtain other distances and angles that would not otherwise be measurable.” To simplify things, trilateration is the method by which 3 satellites send a signal to a receiver which then calculates the distances to each one, and the time at which the signal was sent. The time portion of this process is essential and will be explained later on. The receiver then compares these 3 or even 4 signals and finds the common intersection between them, essentially determining where the GPS user is.
The basic concept of how the Global Positioning System works sounds extremely simple, however what goes on behind the scenes includes processes that become particularly confounding...
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...per day. On the other hand, Einstein’s theory of General Relativity basically says that clocks closer to a large mass will seem to slow down in comparison to those that are isolated in space. As a result, the clocks down here on earth will tick faster than those that are further away. And in this case satellites are found to be around 24,000 km above the Earth which means that clocks found inside the satellites would be ahead of ours by about 45 microseconds a day. With some basic mathematics, we can calculate 45 and subtract 7 to get the magic number of 38, which is the time satellite clocks get ahead of ours each day. To offset this natural error, engineers slow down the ticking frequency of the atomic clocks placed on satellites before they are set to orbit. Satellites literally time travel so that we can find our ways to the nearest gas station when we are lost.
Throughout the day we are constantly checking the time, preparing for the upcoming months, and keeping track of the year. Clocks tell us the time we use as a measurement. It’s how we keep track of those important months and events, such as holidays and birthdays. Although there are many investigations and research being done on the nature of time, many unresolved issues remain.
ADT has serviced the world for over 135 years and prides itself in the products and services they provide. Throughout the years they continue to create new products and improve their existing products. ADT hopes to continue on that path with the creation of the Miniature GPS Tracking Device. Through thorough marketing research and strategic planning ADT hopes to provide this product to all consumers who can benefit from it throughout the world.
The story of the haunted GPS unit served as a commentary on the consequences of over-reliance as well as blind trust in not only navigation units, but also technology in general. It also served as a warning against buying items that were at too good to be true prices from websites where the sellers are not reputable companies but users who have no desire to maintain a good reputation.
Ptolemy explains how he assigned coordinates to the geographical locations he knew on a grid that covered the entire Earth. A world map from it covered as far east as China and as far west as the countries on the east side of the Atlantic ocean, also including a fair bit of Africa down south. Besides the lack of knowledge of the countries beyond the map and the misinformation of the size of the Indian island Sri Lanka, he was only off by fourteen degrees, and even accepted this and that the way he determined longitude was faulty.
Travelling through time is certainly easy to imagine. You step into the time machine; press a few buttons; and emerge out not just anywhere – but anywhen. However, in reality things aren’t quite as convenient as science fiction would suggest, as you will understand later on.
The Global Positioning system has come a long way since William Guier and George Weiffenbach chose to mess around with Sputnik’s location in its orbit. It has gone from being one of the most secretive projects ever developed to being one of the most popular and mostly used technologies in our modern day lives. There is no doubt that the future of GPS technologies hold many more bright and innovative ideas that could once again change how our society lives.
First, we must determine what is meant by time and time travel. Time travelling, defined by David Lewis is as follows “Any traveler departs and arrives at his destination; the time elapsed from departure to arrival is the duration of the journey. But if he is a time traveler, the separation in time between departure and arrival does not equal the duration of his journey”1. Time can be discerned into two different meanings. One meaning of the word is universal time, which is experienced by everyone and everything that is not time travelling. The other, is a traveller’s personal time which is amount of time spent living regardless of when or where they are. If one does not time travel at all, then they will live and die with their personal time, constantly progressing parallel to the universal time (they live for 80 years and die 80 years after their birth). If one does time travel, and they travel 150 years into the past, then die there (and then),
Cartography has existed for thousands of years. From the early days of tribes marking off where their best hunting grounds are, to the modern day of mapping flight paths, cartography has evolved and developed in various ways to what it is today. There are now technologies that allow for people to design maps in ways never imagined before. Computer programmes exist that allow for different types of data to be stored so that accurate representations can be formed. It has been said that, “Maps are pictures of the world’s land surface, showing its features, resources and the way it has been developed.” (Bondi, et al., 1977)
The Library of Congress (2011). What is a GPS? How does it work? [online] Available at: http://www.loc.gov/rr/scitech/mysteries/global.html [Accessed 16th April, 2014]
Let me tell you, if we want an object location on the earth, GPS receiver have to connect with minimum 3 Satellite at the point of time. Now i explain this in a simple way by the help of fig 1.1:
There was a time a person would use a roadmap to get from one location to another. Some also would stop and ask for directions. Today, you seldom see paper maps and people stopping at a local gas station for directions. Many vehicles come with a navigation system that provides a real-time map of the vehicle’s current location as well as systematic directions to requested destination.
Location is described in two ways: absolute location and relative location. Absolute location is the place on earth where a geographic feature is found. To define this they use imaginary lines, the hemisphere; which is half of the globe, equator; is the imaginary line that divides the north and south halves, and the prime meridian; is the imaginary line dividing the earth’s east and west. Another way to call it, is Greenwich meridian. To locate places north or south, geographers use parallel to the equator run imaginary lines, called latitude lines. To complete the grind system, they use imaginary lines that go around the earth over the poles, called longitude lines. Relative location describes a place in comparing to other places around it. Place includes the physical features and cultural aspects of a location, such as climate, landforms, buildings, houses, etc. A region is an area of the earth’s surface with similar characteristics. They may include physical, political,
How does a compass function? A magnet always points north because it has two poles: The south and the north pole.The Earth is a literally a magnet, and it can interact with other magnets in this way, so the north end of a compass magnet attracts to the Earth's magnetic field. Because the Earth's magnetic North Pole attracts the "north" ends of other magnets, it is technically the "South Pole" of the earth’s magnetic field. The geographical pole is the point at 90° northern latitude. It is the north pole that is shown on maps. the geographic North
The Global Positioning System consists of three sections, 1.satellites which are orbiting the planet, 2.there are numerous control/monitoring centers here on the ground, and 3. gps receivers which are used by their owners. The satellites send down signals from orbit, which are received by GPS receivers on the ground in the air or on the water, the GPS receiver then converts this information into a location longitude, latitude and altitude along with time.
Interactions that take place on planet Earth are an ever-changing effect of the Earth’s role in the universe. Interactions stem from many factors, including the Earth’s position in relation to the sun, the axis of the Earth, and that of forces on Earth itself, such as gravity and position. One major interaction that affects everyone and everything on the planet is time. Throughout history, people have experimented with timekeeping in efforts to develop the best system. Through countless trials, the system we use today was developed. In it, time zones were established corresponding to different locations on the Earth. Scientists discovered that different times of year, when the Earth’s position is in different relations to the sun, the weather in the area can be affected, causing seasons. Although spanning worldwide and originating under different circumstances, latitude, longitude, time zones, and seasons are all interrelated through interactions between the Sun and the Earth.