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The Global Positioning System (GPS) is a space-based satellite navigation
system that provides location and time information in all weather conditions,
anywhere on or near the Earth where there is an unobstructed line of sight to
four or more GPS satellites. The system provides critical capabilities to military,
civil and commercial users around the world. It is maintained by the United
States government and is freely accessible to anyone with a GPS receiver.
A GPS receiver calculates its position
by precisely timing the signals sent by
GPS satellites high above the Earth.
Each satellite continually transmits
messages that include
the time the message was transmitted
satellite position at time of message
transmission
In 1956, the German-American
physicist Friedwardt
Winterbergproposed a test of general
relativity (for time slowing in a strong
gravitational field) using accurate
atomic clocks placed in orbit inside
artificial satellites. (Later, calculations
using general relativity determined
that the clocks on GPS satellites would
be seen by Earth's observers to run 38
microseconds faster per day, and this
was corrected for in the design of GPS.)
The gps in my opinion is quite a useful tool. It allows confused travelers to
navigate their surroundings with the ease of a native person
Cost
Purchasing a GPS based on price can be a major disadvantage. If you purchase a
"bargain GPS," you will get what you pay for, and features such as traffic and
up-to-date maps could be lacking.
Reception
GPS devices are limited by having clear access to the satellites that provide the
tracking. In locations with tall buildings or sparse coverage, reception can be
poor.
These are just a few of the problems
there quite a few more.
Dr. Ivan Getting was born in 1912 in New York City. He attended the
Massachusetts Institute of Technology as an Edison Scholar, receiving his
Bachelor of Science in 1933. Following his undergraduate study at MIT, Dr.
Getting was a Graduate Rhodes scholar at Oxford University. He was awarded a
Ph.D. in Astrophysics in 1935.
In 1951, Ivan Getting became the vice president for engineering and research at
the Raytheon Corporation. The first three-dimensional, time-difference-ofarrival position-finding system was suggested by Raytheon Corporation in
response to an Air Force requirement for a guidance system to be used with a
proposed ICBM that would achieve mobility by traveling on a railroad system.
Technology is a valuable tool that in current most people cannot live without.
These tools allows to do things such driving to another state, which in earlier
times would have taken weeks whereas now it takes hours.
Technology is a important tool that helps day in and day out with
ease.
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