How does your mobile phone work? - Healthy Articleses
For most of us a mobile phone is a
part of our lives but I'm sure you're curious minds have always been struck by
such questions as how a mobile phone makes a call and why there are different generations
of mobile communications let's explore the technology behind mobile
communications when you speak on your phone your voice is picked up by your
phone's microphone the microphone turns your voice into a digital signal with
the help of a MEMS sensor and I see the digital signal contains your voice in
the form of zeros and ones an antenna inside the phone receives these zeros and
ones and transmits them in the form of electromagnetic waves electromagnetic
waves transmitted the zeros and ones by altering the wave characteristics such
as the amplitude frequency phase or combinations of these for example in the
case of frequency 0 and 1 are transmitted by using low and high frequencies
respectively so if you could find a way to transmit these electromagnetic waves
to your friends phone you would be able to establish a call however
electromagnetic waves are incapable of traveling long distances.
How does your mobile phone work? - Healthy Articleses |
They lose their
strength due to the presence of physical objects electrical equipment and some
environmental factors in fact if there were no such issues even then
electromagnetic waves would not carry on forever due to the Earth's curved
structure to overcome these issues cell towers were introduced using the
concept of cellular technology in cellular technology a geographic area is
divided into hexagonal cells with each cell having its own tower and frequency
slot generally these cell towers are connected through wires or more
specifically optical fiber cables these optical fiber cables are laid under the
ground or of the ocean to provide national or international connectivity the
electromagnetic waves produced by your phone are picked up by the tower in your
cell and convert them into high frequency light pulses these light pulses are
carried to the base transceiver box located at the base of the tower for
further signal processing processing your voice signal is routed towards the
destination tower upon receiving the pulses the destination tower radiates it
outwards in the form of electromagnetic waves and your friend's phone then
receives the signal this signal undergoes a reverse process and your friend
hears your voice so it's true that mobile communications are not entirely
wireless they do use a wired medium - this is how mobile communications are
carried out however there is a big issue that we intentionally left unanswered
mobile communication is only successful when your tower transfers the signal to
your friends tower but how does your tower know in which cell tower area your friend
is located well for this process the cell tower gets help from something called
a mobile switching center the MSC is the central point of a group of cell
towers before moving further let's explain more information about the MSC when
you purchase a SIM card all the subscription information is registered in a
specified MSC this MSC will be your home MSC the home MSC stores information
such as service plans your current location and your activity status if you
move outside the range of your home MSC the new MSC which serves you instead is
known as a foreign MSC as you enter a foreign MSC region it communicates with your
home MSC in short your home MSC always knows which MSC area you are in to
understand in which cell location the subscriber is within the MSC area the MSC
uses a few techniques one way is to update the subscriber location after a certain
period when the phone crosses a predefined number of towers the location update
is again done the last one of these is when the phone is turned on let's try to
understand all of these procedures with an example suppose Emma wants to call
John when Emma dials John's number the call request arrives at Emma's home MSC upon
receiving John's number the request will be forwarded to John's home MSC now
John's MSC checks for his current MSC if John is in his home MSE the call request
will be immediately sent to his current cell location and it checks whether
John is engaged on another call or if his mobile is switched off if everything
is positive John's phone rings and the call will be connected however if John
is not in his home MSE John's home MSE simply forwards the call requests to the
foreign MSC the foreign MSC will follow the previously explained procedure to
locate John's phone and will then establish the call now let's discuss why the
frequency spectrum is quite important in mobile phone communications to
transfer zeros and ones in digital communication each subscriber is allocated a
frequency range however the frequency spectrum available for cellular
communications is quite limited and there are billions of subscribers this
issue is solved with the help of two technologies one frequency slot
distribution and two multiple access technique in the first technique different
frequency slots are carefully allocated to different cell towers in the
multiple access technique this frequency slot is efficiently distributed
amongst all the active users in the cell area now the big question why are
there different generations of mobile phone technologies 1/g originally allowed
users for the first time to carry a phone without a cable attached to it but 1g
suffered from two major problems the first problem was that the wireless transmission
was in an analog format analog signals are easily altered by external sources
so it provided poor voice quality and poor security the second problem was that
it used the frequency division multiple access technique which used the
available spectrum in an inefficient way these factors paved the way for the
second generation of mobile communications 2g used digital multiple access technologies
namely TDMA or CDMA technology the second generation also introduced a
revolutionary data service SMS and internet browsing 3G technology was focused
on giving a higher data transfer speed it used aw CD multiple access technique
along with an increase in bandwidth to achieve this the 3G speed of 2 Mbps
allowed the transfer of data for uses such as GPS videos voice calls etc 3G was
a huge step in the transformation of the basic phone to a smart phone next came
4G which achieved speeds of 20 to 100 Mbps this was suitable for
high-resolution movies and television this higher speed was made possible due to
the of multiple access technology and my mode technology my mo uses multiple
transmitter receiver antennas inside both the mobile phone and the towers the
next generation of mobile communication 5g to be rolled out soon will use
enhanced MIMO technology and millimeter waves it will provide seamless
connectivity to support the internet of things such as driverless cars and
smart homes would you like to learn how a touchscreen works please check out this
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How does your mobile phone work? - Healthy Articleses
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