Skip to main content

GLOBAL TELECOMMUNICATIONS.

CONSTELLATIONS  OF LOW-ORBITING  satellites  hold  the key  to  today's    flexible   global  telephone  networks .These  systems integrate  satellite   communications  with  existing  land line  and  cellular  network  to provide   truly  global  coverage  from  a  mobile  phone  .This  enables   people, even      in  remote   areas even  those  on  tiny  pacific   islands   or  high  in the  Himalayas   ,to  keep  in  touch  with   rest  of  the  world .Satellite  system s   are  the    next  logical    step    in  the  mobile  -phone  revolution  that  swept  the  world  in  the  late  1990's.
IRIDIUM    was  the  first  system  to  offer   a commercial  service .It  was  conceived   and  developed  by   the  US  electronics company   Motorola   ,and  began  operation  on 1  November  1998.The  system  was  named  after  the  77th  chemical  element in  the periodic Table  ,as there  were  originally to  be  77 satellites  in the   network.Other  networks   offering  a  similar    service  include  Global star  , which  operates  with  a constellations   of  48 satellites.
IRIDIUM  SATELLITE  ORBITAL  NETWORK.
The  Iridium  network  consists  of   66  satellites  ,each  providing  a  coverage  of  16  million square  km (6  million  square mile).It  offers  a  constant  service  ,as  there  will always  be  one    or  more satellite    over  the   horizon  .The   network  operates  as  a  constellations h  means  which  means  that  a  failed  or  malfunctioning  satellite   will  not  impede   the  system's  ability   to  provide global  coverage.When  a  call  is  made  it  is  routed to the   nearest  satellite  ,and   then  relayed  around  the  world  to  its  destination.If  the  destination  is  the  land  based  telephone  , the  last  satellite    in  the  chain    feed  the  signal     to  a"gateway" ground  station  .This  gateway  then  connects   with  the  existing   land line  telephone  system. ,

 

Comments

Popular posts from this blog

REVOLUTIONS-INDUSTRIAL AND INFORMATION

INDUSTRIAL   REVOLUTION  Starts   in   Europe  particularly  in  England  in  eighteen  century.It   changed  the  whole   of Europe   and   England 's  economy.During  this  period    New    machines  are  invented  in   England   to  speed  up  the    spinning  of  wool  and  cotton .At  first  they  were  powered  by  water  wheels  but  later steam  engines   are  developed.Iron   become  cheaper  and  stronger  as  Iron  making  techniques   improved.Canals  are  dug  to  carry   coal   from  the  mines and  to  transport  finished  goods.After   some times  Railways    replaced  canals  .The  first  railways   opens  in   1825.Big  changes   took  place   in  Agriculture  .Machines  replaced    human  power,thus  now  fewer  people   are  to  grow  food.This  forced  people   to  leave  the  country side   to  find  work  in  mills  and  factories.Industrial   town   grow   rapidly.   MASS  PRODUCTION -  The  most  unique   thing   of  Industrialization    was   mass  produ

WEB SITES TO ENTERTAIN YOU

If  you   get  bored   from  the   web  viewing  the  same  stuff    over  and  over  again -social media  ,blogs,   news  etc  then  you  certainly   need  some  thing  different  that  can  soothe   your  soul and  give  you some  kind of entertainment  then  here  are some  sites  that  can  solve  your  purpose. Bored Panda   Bored Panda is the place you want to be when you want to discover interesting and visually appealing content. It's a blog that publishes regular updates on the coolest finds in travel, photography, illustration, animals, DIY, technology, design and all sorts of other great categories. You can also create an account to vote posts up or down. Brain Pickings .      Try expanding your knowledge by diving deep into the incredibly useful and thought-provoking blog posts on Brain Pickings, which is a popular blog run by MIT fellow Maria Popova. She's the one who does all the research and writing for each

BEST INTERESTING SITES

 Human achievement, human folly, inspirational stories of compassion and courage, and horrific stories of terrible crimes are all represented here. These  sites   are  inspiring  sometimes  shocking   but  they  are   very interesting  to  view  . Some  of  such  websites  are  - Here  , SFW  means  "safe for  work" with all  clean  content .NSFW  means  "not  safe  for  work.Its  content  may  not  be  safe  for  work. Distractify (SFW) Distractify.com is about human emotion. These viral stories are hand-picked by the editors because they impact the human condition in some way. The photography is often impressive. You can find life hacks on how to raise your children in a safer way, tips on how to improve your relationship with your dog, and topics beyond. Compelling and addictive content fills the pages of Distractify.     Listverse (SFW) .  Listverse is a collection of thousands of gems of human knowledge, presented in li