The history of mobile phones charts the development of devices
which connect
wirelessly to the public switched telephone network. The transmission of speech
by radio
has a long and varied history going back to Reginald
Fessenden's invention and shore-to-ship demonstration of radio telephony,
through the Second World War with military use of radio telephony links.
Hand-held radio transceivers have been available since the 1940s. Mobile
telephones for automobiles became available from some telephone companies
in the 1940's. Early devices were bulky and consumed high power and the
network supported only a few simultaneous conversations. Modern cellular
networks allow automatic and pervasive use of mobile phones for voice
and data communications.
Mobile phone history is often divided into generations to mark significant
step changes in capabilities as the technology improved.
IN EARLIER TIMES,there was only post offices through which people post letters
to one another,but todays world is world of mobile phones..now its very easy to
contact a person within seconds and work done in seconds.....
EARLIER WORLD,
TOD
AYS WORLD.....
IN TODAYS WORLD
every person has a mobile every work is done
through mobiles and mobiles companies got a heavy profit.....................
