Today whole world is connected, we can call anyone in any part of the world within fraction of time. lets us know electronics behind it.
How does a phone call work
phone is two way radio, consisting of a radio transmitter and a radio receiver. phone converts our voice into an electrical signal , which is then transmitted via radio waves to the nearest cell tower.
cell phones use radio waves to communicate. radio waves carry the information and travel in air at the speed of light. cell phones transmit radio waves in all directions.
 |
| Phone |
Antenna
cell phones contain at least one radio antenna in order to transmit or receive radio signals. An antenna converts an electric signal to the radio wave.
An antenna is a metallic element for transmitting and receiving specific frequencies of radio waves. older generation phones has ex tractable antennas, modern cell phones has inbuilt antennas. nowadays we have inbuilt Wi -Fi , Bluetooth and GPS.
Optical fiber communication.
To make a call to far distance ( from India to America ) few system is involved back-end. previous days when we used make international calls it would connect with the help international gateway exchanges(switches). nowadays with the help of fiber optics and voice over internet protocol(VoIP) international calls can be dialed without an operator.
Optical fibre is connected between countries through sea bed.
When we diall international number from our phone, our ISP will route the call to international gateway with the help of routing then other end ISP will connect our call to end user.
Future
Due to optical fibre laying under sea telecommunications throughout the world has became cheaper.
International calls using internet has become very cheap already.
