description about mobile phones and its basic parts. mobile phone as an electronic device. history of mobile phone and its functions
Salalah College of Technology
Hamed Muhammed Suhail Harsoosi
A mobile phone is a wireless handheld device that allows users to make
calls and send text messages, among other features. The earliest
generation of mobile phones could only make and receive calls. Today’s
mobile phones, however, are packed with many additional features, such
as Web browsers, games, cameras, video players and even navigational
A mobile phone may also be known as a cellular phone or simply cell
phone. Modern mobile phones also support a wide variety of other
services such as text messaging, MMS, email, Internet access, short-range
wireless communications (infrared, Bluetooth), business applications,
gaming, and photography. Mobile phones that offer these and more
general computing capabilities are referred to as smart phones.
When the first mobile phones were introduced, their only function was to
make calls, and they were so bulky it was impossible to carry them in a
Later, mobile phones belonging to the Global System for Mobile
Communications (GSM) network were capable of sending and receiving
text messages. As these devices evolved, they became smaller and more
features were added, such as multimedia messaging service (MMS),
which allowed users to send and receive images.
Most of these MMS-capable devices were naturally equipped with
cameras, which allowed users to capture photos with the built-in camera,
add captions, and send them to friends and relatives who also had MMScapable phones. A mobile phone typically operates on a cellular network,
which is composed of cell sites scattered throughout cities, countryside's,
and even mountainous regions.
Main Parts of Mobile phones
Following are the main basic parts of any mobile phone.
1. A circuit board
2. An antenna
3. A liquid crystal display (LCD)
4. A keyboard
5. A microphone
6. A speaker
7. A battery
A circuit board
The circuit board is the heart of the system. The analog-to-digital and
digital-to-analog conversion chips translate the outgoing audio signal
from analog to digital and the incoming signal from digital back to
analog. The microprocessor handles all of the housekeeping chores for
the keyboard and display, deals with command and control signaling with
the base station and also coordinates the rest of the functions on the
When talking on a cell phone, a transmitter takes the sound of your voice
and encodes it onto a continuous sine wave. A sine wave is just a type of
continuously varying wave that radiates out from the antenna and
fluctuates evenly through space. Sine waves are measured in terms of
frequency, which is the number of times a wave oscillates up and down
per second. Once the encoded sound has been placed on the sine wave,
the transmitter sends the signal to the antenna, which then sends the
signal out. Finally, the Radio Frequency amplifiers handle signals
traveling to and from the antenna.
A liquid crystal display (LCD)
The short name for Liquid Crystal Display is LCD. The led cell consists
of two glass plates that are prepared with ITO (indium-tinoxide)
electrodes during a photolithographic process. Between these plates a
layer of liquid crystal is applied. On the outsides of the cell two
polarization filters are attached.
Between the fixed and liquid phase the molecules naturally have a rotated
structure. By etching vertical ITO-paths on the glass plate below and
horizontal paths on the plate above you get a lattice of ITO-paths by
which it is possible to create a different voltage on every ‘intersection’.
By adapting the voltage, the rotated structure of the molecules can be
influenced in order to regulate the light transmission. Now it is possible
to create pixels that all can be switched on and off. This can be controlled
by a chip.
Any 12 key telephone keypad can be used as a computer terminal
keyboard. The speed and efficiency of the Phone Keyboard is faster and
easier than all previous data entry methods using any phone or any twelve
sensor keypad. All data entered on any standard computer keyboard can
be entered using any 12 key phone keypads.
A microphone, colloquially mic or mike is an acoustic-to-electric
transducer or sensor that converts sound in air into an electrical signal.
Microphones are used in many applications such as telephones, hearing
aids, public address systems for concert halls and public events, motion
picture production, live and recorded audio engineering, two-way radios,
megaphones, radio and television broadcasting, and in computers for
recording voice, speech recognition, VoIP, and for non-acoustic purposes
such as ultrasonic checking or knock sensors.
In any sound system, ultimate quality depends on the speakers. The best
recording, encoded on the most advanced storage device and played by a
top-of-the-line deck and amplifier, will sound awful if the system is
hooked up to poor speakers. Cell phones have such tiny speakers and
microphones that it is incredible how well most of them reproduce sound.
As you can see in the picture above, the speaker is about the size of a
dime and the microphone is no larger than the watch battery beside it.
Speaking of the watch battery, this is used by the cell phone's internal
While there are many different types of batteries, the basic concept by
which they function remains the same. When a device is connected to a
battery, a reaction occurs that produces electrical energy. This is known
as an electrochemical reaction. Today, batteries are all around us. They
power our wristwatches for months at a time. They keep our alarm clocks
and telephones working, even if the electricity goes out.
Cell phones have completely changed our world. People now use them
for leisure time, business, school, and so much more. Cell phones are not
just cell phones anymore. People rely on them for video chatting for
conference calls, searching the web for nearby restaurants, taking pictures
of their travels, using a GPS tracking system, etc. The majority of people
own cell phones nowadays and people rely on them more than ever. Cell
phones have become a part of everyday life and I could not imagine what
it would be like having to live without having a cell phone. Being away at
school I still am able to keep in contact with my parents and grandparents
although I am far away from them. Cell phones are a vital service in the
human connection because people are able to have connections that the
past decades never imaged. The cell phone is an incredible invention that
has altered our lives forever.