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A
Seminar Report
On
HOW CELL PHONE WORK
(MOBILE COMMUNICATION)
Submitted In partial fulfilment of
The requirement for the award of the Degree Of
BACHELOR OF TECHNOLOGY
IN
APPLIED ELECTRONICS AND INSTRUMENTATION ENGINEERING
By:
KUMAR GAURAV
University Roll No. = 1201210282
DEPARTMENT OF APPLIED ELECTRONICS AND
INSTRUMENTATION ENGINEERING
GANDHI INSTITUTE OF ENGINEERING AND TECHNOLOGY
GUNUPUR – 765022
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This is to certify that the seminar report work entitled “HOW CELL PHONE
WORK ? (MOBILE COMMUNICATION)”is the bonafide work carried out by
KUMAR GAURAV (1201210282) student of BACHELOR OF
TECHNOLOGY, GANDHI INSTITUTE OF ENGINEERING AND
TECHNOLOGY during the academic year 2015-16 in partial fulfilment
of the requirements for the award of the Degree of BACHELOR OF
TECHNOLOGY in APPLIED ELECTRONICS AND INSTRUMENTATION
ENGINEERING.
MR .AJIT PATRO MR.BHIBHU PRASAD
Seminar coordinator seminar Guiide
Mr.SHUBHRAJIT PRADHAN
HOD(AE&I)
ABSTRACT
Around the world there are millions of people use cell phones. Walking and talking, working on the train, always in contact, never out of touch—cellphones have dramatically changed the way we live and work. No one knows exactly how many little plastic handsets there are in the world, but the best guess is that there over 7 billion subscriptions. That's more than the planet's population! In developing countries, where large-scale land line networks (ordinary telephones wired to the wall) are few and far between, over 90 percent of the phones in use are cellphones. Cellphones (also known as cellular phones and, chiefly in Europe, as mobile phones or mobiles) are radio telephones that route their calls through a network of masts linked to the main public telephone network. Here's how they work.
Although they do the same job, land lines and cellphones work in a completely different way. Land lines carry calls along electrical cables. Cut out all the satellites, fiber-optic cables, switching offices, and other razzmatazz, and land lines are not that much different to the toy phones you might have made out of a piece of string and a couple of baked bean cans. The words you speak ultimately travel down a direct, wired connection between two handsets. What's different about a cellphone is that it can send and receive calls without wire connections of any kind. How does it do this? By using electromagnetic radio waves to send and receive the sounds that would normally travel down wires.
Whether you're sitting at home, walking down the street, driving a car, or riding in a train, you're bathing in a sea of electromagnetic waves. TV and radio programs, signals from radio-controlled cars, cordless phone calls, and even wireless doorbells—all these things work using electromagnetic energy: undulating patterns of electricity and magnetism that zip and zap invisibly through space at the speed of light (300,000 km or 186,000 miles per second). Cellphones are by far the fastest growing source of electromagnetic energy in the world around us.
ACKNOWLEDGEMENT
I do take it as a pleasure to express my deepest sense of gratitude and a respect to our eminent and most dynamic person Mr. Subhrajit Pradhan, Head of the Department ,Applied Electronics and Instrumentation Engineering for his affection guidance and support throughout my seminar .
I am grateful to coordinator Ajit Kumar Patro who throughout their deep knowledge helped us in understanding in a simple and better way.
I am also thankful to Bibhu Prasad who guided me through the path of practically experience without whose support this seminar report would not have been possible.
In the last but not least, special thanks are due to my B.Tech. teachers. I finally thank all the well wishers and friends who directly or indirectly helped me in the successful completion of my work.
KUMAR GAURAV
CONTENTS
TITLE PAGE
ACKNOWLEDGEMENTS.................................................................................i
ABSTRACT.........................................................................................................ii
CHAPTER 1 INTRODUCTION
1.1 Introduction to different feature of cellphone..................................................1
1.2 What is a Mobile…………………………………………………………..…1 1.3 Mobile communication……………………………………………………..1 CHAPTER 2 History of the Cell Phones 2.1 First Generation …………………………………………………………......2 2.2 Second Generation………………………………………………………….. 2 2.3 Third Generation……………………………………………………………..3 2.4 4G Generation…………………………………………………………..……3 CHAPTER 3 Basics of the Cell Phones 3.1 Parts of A Cell Phone...................................................................... ……....4 3.2 Main Uses of Cell Phones…………….......................................................4
3.2.1 Popular mobile business applications are..............................................5 3.2.2 Cell Phone Feature................................ ………………………………6
CHAPTER 4 How Cell Phones work 4.1 Cell Phone Networks……………………………………………………..7 4.2 How does a Cell Phone work??..................................................................7 CHAPTER 5 Setting up a call process 5.1 Making a call………………………………………………………………..8 5.2 Receiving a call……………………………………………………………………10
CHAPTER 6 Cellphone calls travel 6.1 How cellphone masts help…………………………………………………11 CHAPTER 7: Invention of mobile 7.1 Who invented cellphones?.............................................................................14 CHAPTER 8 ADVANTAGES & DISADVANTAGES OF MOBILE 8.1 Advantages………………………………………………………………….16 8.2 Disadvantages…………………………………………………………….... 16 CONCLUSION…………………………………………………………………17 REFERENCE......................................................................................................18
1.
CHAPTER 1 INTRODUCTION
1.1 Introduction to different feature of cellphone
• Around the world there are millions of people use cell phones. • The cell phones are the wonderful gadget from it we can talk to
anyone, anywhere in this planet. • The first cell phones is invented by Charles E. Alden in year 1906. • A successful demonstration of a true, fully functioning mobile
phone was dated way back 1973, demonstrated by Martin Cooper of Motorola Company.
1.2 What is Mobile Communications?
• A wireless form of communication in which voice and data information is emitted, transmitted and received via microwaves. This type of communication allows individuals to converse with one another and/or transmit and receive data while moving from place to place. Some examples include: cellular and digital cordless telephones; pagers; telephone answering devices; air-to-ground telecommunications; and satellite-based communications.
1.3 What is a Mobile?
• The mobile phone or cell phone is a long-range, portable electronic device used for mobile communication. In addition to the standard voice function of a telephone, current mobile phones can support many additional services such as SMS for text messaging, email, packet switching for access to the Internet, and MMS for sending and receiving photos and video. Most current mobile phones connect to a cellular network of base stations (cell sites), which is in turn interconnected to the public switched telephone network (PSTN).
CHAPTER 2 History of the Cell Phones
2.1 History of the Cell Phones
• In the beginning, two-way radios (known as mobile rigs) were used
in vehicles such as taxicabs, police cruisers, ambulances, and the
like,
• Users could not dial phone numbers from their mobile radios in
their vehicles.
• A large community of mobile radio users, known as the
mobilizers, popularized the during the early 1940s, Motorola
developed a backpacked two-way radio, the Walkie-Talkie and
later developed a large hand-held two-way radio for the US
military. This battery powered “Handy-Talkie” (HT) was about the
size of a man’s forearm.
Early Years
• In December 1947, Douglas H. Ring and W. Rae Young, Bell Labs
engineers, proposed hexagonal cells for mobile phones.
• Cellular technology was undeveloped until the 1960s, when
Richard H. Frenkiel and Joel S. Engel of Bell Labs developed the
electronics.
• Radio telephony was introduced on passenger airplanes for air
traffic security..
• Recognizable mobile phones with direct dialing have existed at
least since the 1950s.
• The first fully automatic mobile phone system, called MTA
(Mobile Telephone system A), was developed by Ericsson and
commercially released in Sweden in 1956.
• One of the first truly successful public commercial mobile phone
networks was the ARP network in Finland, launched in 1971.
• Dr. Martin Cooper of Motorola, made the first US analogue mobile
phone call on a larger prototype model in 1973. phone call on a larger prototype model in 1973.
2.
2.2 GENERATION
2.2.1 First Generation
• The first handheld mobile phone to become commercially available
to the US market was the Motorola DynaTAC 8000X, which
received approval in 1983
• Mobile phones began to proliferate through the 1980s with the
introduction of “cellular” phones based on cellular networks with
multiple base stations.
2.2.2 Second Generation
• In the 1990s, ‘second generation’ (2G) mobile phone systems such
as GSM, IS-136 (“TDMA”), iDEN and IS-95 (“CDMA”) began to
be introduced.
• in 1991 the first GSM network (Radiolinja) opened in Finland.
2.2.3Third Generation
• At the beginning of the 21st century, 3G mobile phone systems
such as UMTS and CDMA2000 1xEV-DO have now begun to be
publicly available.
• Live streaming of radio and television to 3G handsets is one future
direction for the industry, with companies from Real and Disney
recently announcing services
2.2.4 What is 4G TECHNOLOGY?
• 4G is short for Fourth Generation wireless Technology. It is
basically the extension in the 3G technology with more bandwidth
and services offers in the 3G. The expectation for the 4G
technology is basically the high quality audio/video streaming over
end to end Internet Protocol. If the Internet Protocol (IP)
multimedia sub-system movement achieves what it going to do,
nothing of this possibly will matter. WiMAX or mobile structural
design will become progressively more translucent, and therefore
the acceptance of several architectures by a particular network
operator ever more common.
3.
CHAPTER 4 How Cell Phones work 4.1Cell Phone Networks
• A cellular phone network uses a number of short-range radio transmitter-receivers to communicate simultaneously with many mobile phones
• Commercial wireless networks have evolved over the past twenty years by developing advanced technologies
• The most common type of wireless network is a cellular network.
• Cellular technology is the leading telecommunications technology because of its high capacity, flexible deployment and cost-effectiveness.
How does a Cell Phone work??
• Wireless network carriers use a system of areas or "cells“ served by radio communications
• The signal footprint of each radio antenna defines the location and size of its cell.
• As the mobile phone moves, the call is dropped by the cell being exited and simultaneously picked up by the cell being entered.
• The antennas can be mounted on freestanding towers, poles,
• Radio signals can be blocked by trees, buildings, hills and valleys,
• A consumer needs two things to use a mobile phone:a handset (or mobile communications device)And a phone service plan from a wireless network carrier or service provider.
CHAPTER 3 Basics of the Cell Phones
3.1Basics of the Cell Phones
• Cellular phone is a portable telephone that does not use a wired
connection.
• A cellular phone network uses a number of short-range radio
transmitter-receivers to communicate.
• The wireless network is connected to the public telephone system,
another wireless carrier network or the Internet for completing calls
to another phone or to a computer.
Inside a Cell Phone
3.2 Parts of a Cell Phone
• A microscopic microphone
• A speaker
• An LCD or plasma display
• A keyboard not unlike the one we saw in a TV remote control
• An antenna
• A battery
• An amazing circuit board containing the guts of the phone
3.3 Main Uses of Cell Phones
• Voice calling
• Voice mail
• Messaging
• Mobile content
• Gaming
• Personalize your phone –Play music
• Take photos or videos
• Download and view images
4.
• Organize personal information
• Shop
• Bank
• Location-based services
• Shop
• Bank.
Business Uses for Cell Phones
• increase business productivity.
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1. E-mail
2. Messaging
3. Remote data
4. Customer relationship management (CRM)
5. Field service
6. Supply chain management (SCM)
Cell Phone Features
3.4 General features
• A network carrier is necessary to use cellphone
• Mobile phones include an alarm.
• can also send and receive data and faxes
• send short messages
• Provide full Internet access
• allow for sending and receiving pictures
• Sound and video recording is often also possible.
• Push to talk, available on some mobile phones,
• Downloadable ring tones and logos, are also possible.
Multi-Mode Cell Phones
• A phone which is designed to work on more than one GSM radio
frequency.
5.
• Some multi-mode phones can operate on analog networks as well
most mobile phone networks now use one of two standards, GSM
or CDMA. A third standard, iDEN is found in over 20 countries
around the world.
• Integrated Digital Enhanced Network (iDEN) is a mobile
telecommunications technology, developed by Motorola, which
provides its users the benefits of a trunked radio and a cellular
telephone.
Data Communications
• Mobile phones used for data communications such as SMS
messages, browsing mobile web sites, and even streaming audio
and video files.
• Most cell phones can be used as wireless modems (via cable or
Bluetooth),.
• With newer smart phones, screen resolution and processing power
has become bigger and better.
• Some new phone CPUs run at over 400 MHz. Many complex
programs are now available for the various smart phones,
• Connection speed is based on network support.
New Features
• Text messaging and e-mail.
• Java, Microsoft operating systems, Linux, or Symbian OS, may
• Bluetooth
• Ring tones and screensavers for certain phones.
Video Cameras
• Video camera in many smart phones now
• Nokia N95, which has a 5M pixel camera.
• Modern software allows simple editing and publishing of video
content from phones,
6.
CHAPTER 5 Setting up a call process
5.1 Setting up a call process
• when powered on, the phone does not have a frequency/ time slot to it yet; so it scans for the control channel of the BTS and picks the strongest signal
• then it sends a message (including its identification number) to the BTS to indicate its presence
• the BTS sends an acknowledgement message back to the cell phone
• the phone then registers with the BTS and informs the BTS of its exact location
• after the phone is registered to the BTS, the BTS assigns a channel to the phone and the phone is ready to receive or make calls
5.1.1MAKING A CALL
1. when the phone needs to make a call it sends an access request (containing phone identification, number) using RACH to the BTS; if another cell phone tries to send an access request at the same time the messages might get corrupted, in this case both cell phones wait a random time interval before trying to send again
2. Then the BTS authenticates the cell phone and sends an acknowledgement to the cell phone
3. The BTS assigns a specific voice channel and time slot to the cell phone and Transmits the cell phone request to the MSC via BSC
4. The MSC queries HLR and VLR and based on the information obtained it routes the call to the receiver’s BSC and BTS
5. The cell phone uses the voice channel and time slot assigned to it by the BTS to communicate with the receiver
5.2 RECEIVING A CALL
1. when a request to deliver a call is made in the network, the MSC or the receiver’s home area queries the HLR; if the cell phone is located in its home area the call is transferred to the receiver; if the cell phone is located outside its home area, the HLR maintains a record of the VLR attached to the cell phone
2. Based on this record, the MSC notes the location of the VLR and indicated the corresponding BSC about the incoming call
3. The BSC routes the call to the particular BTS which uses the paging channel to alert the phone
4. The receiver cell phone monitors the paging channel periodically and once it receives the call alert from the BTS it responds to the BTS
5. The BTS communicates a channel and a time slot for the cell phone to communicate
6. Now the call is established.
Pic: -receiving process
CHAPTER 6 How cellphone calls travel
• When you speak into a cellphone, a tiny microphone in the handset converts the up-and-down sounds of your voice into a corresponding up-and-down pattern of electrical signals. A microchip inside the phone turns these signals into strings of numbers. The numbers are packed up into a radio wave and beamed out from the phone's antenna (in some countries, the antenna is called an aerial). The radio wave races through the air at the speed of light until it reaches the nearest cellphone mast.
--Photo: Engineers repair a cellphone mast.
The mast receives the signals and passes them on to its base station, which effectively coordinates what happens inside each local part of the cellphone network, which is called a cell. From the base station, the calls are routed onward to their destination. Calls made from a cellphone to another cellphone on the same network travel to their destination by being routed to the base station nearest to the destination phone, and finally to that phone itself. Calls made to a cellphone on a different network or a land line follow a more lengthy path. They may have to be routed into the main telephone network before they can reach their ultimate destination.
How cellphone masts help
At first glance, cellphones seem a lot like two-way radios and walkie talkies, where each person has a radio (containing both a sender and a receiver) that bounces messages back and forth directly, like tennis players returning a ball. The problem with radios like this is that you can only use so many of them in a certain area before the signals from one pair of callers start interfering with those from other pairs of callers. That's why cellphones are much more sophisticated—and work in a completely different way.
A cellphone handset contains a radio transmitter, for sending radio signals onward from the phone, and a radio receiver, for receiving incoming signals from other phones. The radio transmitter and receiver are not very high-powered, which means cellphones cannot send signals very far. That's not a flaw— it's a deliberate feature of their design! All a cellphone has to do is communicate with its local mast and base station; what the base station has to do is pick up faint signals from many cellphones and route them onward to their destination, which is why the masts are huge, high-powered antennas (often mounted on a hill or tall building). If we didn't have masts, we'd need cellphones with enormous antennas and giant power supplies—and they'd be too cumbersome to be mobile. A cellphone automatically communicates with the nearest cell (the one with the strongest signal) and uses as little power to do so as it possibly can (which makes its battery last as long as possible and reduces the likelihood of it interfering with other phones nearby).
What cells do
So why bother with cells? Why don't cellphones simply talk to one another directly? Suppose several people in your area all want to use their cellphones at the same time. If their phones all send and receive calls in the same way, using the same kind of radio waves, the signals would interfere and scramble together and it would be impossible to tell one call from another. One way to get around this is to use different radio waves for different calls. If each phone call uses a slightly different frequency (the number of up-and-down undulations in a radio wave in one second), the calls are easy to keep separate. They can travel through the air like different radio stations that use different wavebands.
That's fine if there are only a few people calling at once. But suppose you're in the middle of a big city and millions of people are all calling at once. Then you'd need just as many millions of separate frequencies—more than are usually available. The solution is to divide the city up into smaller areas, with each one served by its own masts and base station. These areas are what we call cells and they look like a patchwork of invisible hexagons. Each cell has its base station and masts and all the calls made or received inside that cell are routed through them. Cells enable the system to handle many more calls at once, because each cell uses the same set of frequencies as its neighboring cells. The more cells, the greater the number of calls that can be made at once. This is why urban areas have many more cells than rural areas and why the cells in urban areas are much smaller
How cellphone cells handle calls
This picture shows two ways in which cells work.
Simple call
If a phone in cell A calls a phone in cell B, the call doesn't pass directly between the phones, but from the first phone to mast A and its base station, then to mast B and its base station, and then to the second phone.
Roaming call
Cellphones that are moving between cells (when people are walking along or driving) are regularly sending signals to and from nearby masts so that, at any given time, the cellphone network always knows which mast is closest to which phone.
If a car passenger is making a call and the car drives between cells C, D, and E, the phone call is automatically "handed off" (passed from cell to cell) so the call is not interrupted.
The key to understanding cells is to realize that cellphones and the masts they communicate with are designed to send radio waves only over a limited range; that effectively defines the size of the cells. It's also worth pointing out that this picture is a simplification; it's more accurate to say that the masts sit at the intersections of the cells, but it's a little easier to understand things as I've shown them.
Chapter 7: invention of mobile
• Who invented cellphones?
How did we get from land lines to cellphones? Here's a quick history:
• 1873: British physicist James Clerk Maxwell (1831–1879) published the theory of electromagnetism, explaining how how electricity can make magnetism and vice-versa. Read more about his work in our main article on magnetism.
• 1876: Scottish-born inventor Alexander Graham Bell (1847–1922) developed the first telephone while living in the United States (though there is some dispute about whether he was actually the original inventor). Later, Bell developed something called a "photophone" that would send and receive phone calls using light beams. Since it was conceived as a wireless phone, it was really a distant ancestor of the modern mobile phone.
• 1888: German physicist Heinrich Hertz (1857–1894) made the first electromagnetic radio waves in his lab.
• 1894: British physicist Sir Oliver Lodge (1851–1940) sent the first message using radio waves in Oxford, England.
• 1899: Italian inventor Guglielmo Marconi (1874–1937) sent radio waves across the English Channel. By 1901. Marconi had sent radio waves across the Atlantic, from Cornwall in England to Newfoundland. Marconi is remembered as the father of radio, but pioneers such as Hertz and Lodge were no less important.
• 1906: American engineer Reginald Fessenden (1866–1932) became the first person to transmit the human voice using radio waves. He sent a message 11 miles from a transmitter at Brant Rock, Massachusetts to ships with radio receivers in the Atlantic Ocean.
• 1920s: Emergency services began to experiment with cumbersome radio telephones.
• 1940s: Mobile radio telephones started to become popular with emergency services and taxis.
• 1946: AT&T and Southwestern Bell introduced their Mobile Telephone System (MTS) for sending radio calls between vehicles.
• 1960s: Bell Laboratories (Bell Labs) developed Metroliner mobile cellphones on trains.
• 1973: Martin Cooper (1928–) of Motorola made the first cellphone call using his 28-lb prototype DynaTAC phone.
• 1975: Cooper and his colleagues were granted a patent for their radio telephone system. Their original design is shown in the artwork you can see here.
• 1978: Analog Mobile Phone System (AMPS) was introduced in Chicago by Illinois Bell and AT&T.
• 1982: European telephone companies agreed a worldwide standard for how cellphones will operate, which was named Groupe Speciale Mobile and later Global System for Mobile (GSM) telecommunications.
• 1984: Motorola DynaTAC became the world's first commercial handheld cellphone. Take a look at a picture of Martin Cooper and his DynaTAC!
• 1995: GSM and a similar system called PCS (Personal Communications Services) were adopted in the United States.
• 2001: GSM had captured over 70 percent of the world cellphone market. • 2000s: Third-generation (3G and 3.5G) cellphones were launched, featuring
faster networks, Internet access, music downloads, and many more advanced features based on digital technology.
• 2007: Apple's iPhone revolutionized the world of cellphones, packing what is effectively a touch-controlled miniature computer into a gadget the same since as a conventional cellular phone.
• 2011: World Health Organization published view that cellphones are "possibly carcinogenic" to humans.
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Mobile phones have altered our way of life to an unbelievable degree. Anytime some
old member of a family applies tales regarding prior modes of communication like
beepers, postal letters and telegrams, the children of Twenty-first century feel really
surprised. It would appear that the people relevant the stories regarding telegrams fit
in to a few other planet. So, it’s a fact that the cellular phone technology has started a
new period on our planet that has uprooted the old fashioned lifestyle entirely.
However, it doesn’t mean this technologies has no effect on people adversely.
Everything on the planet earth has two attributes; advantages and disadvantages. The
same will go true for the phone technologies. The technology is effective as well as
disadvantageous. In this article, the advantages will be considered towards the
disadvantages in order to obtain a accurate understanding of the effects of mobile
phones on individual life.
8.1 The Advantages of the Technologies
• It is said that “phones possess turned the world into a global town.” The
declaration appears precisely true. Residing in one part of the world, we can
talk to our family members residing in an additional corner of the world
effortlessly.
• The cell phone technologies have speeded up small and big companies. The
business events around the world can communicate with one an additional in a
few of mere seconds. They can offer and determine quickly. Consequently, the
business world has been enhanced to a astonishing extent due to fraxel
treatments.
• It’s created individuals in contact along with one an additional. In this way,
mobile phones possess urged individual conversation.
• To provide a network for communication, lots of individuals are needed to
handle the duties. Hence, many jobless people have obtained good work for all
of them due to fraxel treatments.
8.2 The Disadvantages of the Technologies
• The finest disadvantage of it is this technologies have impacted the natural
method of human interaction badly. Individuals stay hectic using their tissue
even when sitting in a team of other people.
• There are many tales about the people who fulfilled accidents because of to
keeping focus on their own mobile phone while driving. Therefore, this is one
of the greatest disadvantages of these types of devices.
• Mobile mobile phones are used by criminals to inform one another about their
filthy ideas. And, their own crime strategies are invented by using this
technologies in the majority of cases.
• Mobile phones also have increased up street offences and breach of moral
ideals. Lots of immoral, so-called love tales discover their existence through
the misuse of this technology.
16
CONCLUSION
• Mobile communication is the fastest growing part of network based wireless technology.
• Around the world there are millions of people use cell phones. The cell phones are the wonderful gadget from it we can talk to anyone, anywhere in this planet.
• This type of communication allows individuals to converse with one another and/or transmit and receive data while moving from place to place.
REFERENCE
Books
• The Cellphone by Guy Klemens. Jefferson, NC: McFarland, 2010. • Constant Touch: A Global History of the Mobile Phone by Jon Agar. New
York: Totem, 2005.
• Principles of Mobile Communication, Author: Stüber, Gordon L. • Notes of PMC.
Websites
• Privateline.com: Digital wireless
• Images from google
