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CHAPTER ONE
INTRODUCTION
1.1 Background of the Study
The Wireless technology was devised in 1880 by Alexander Graham Bell and Sumner
Tainted when the photo phone invented Carson (2007), Nowadays, there are many
types of wireless devices being used to communicate. Mobile phone and Wireless
Network are the part of our daily life throughout the world. The Wi-Fi device allows
the exchange (receiving and sending) data through wirelessly and Wi-Fi devices emit
radio waves. Devices that use Wi-Fi are tablet pc, cell phone, audio player, PC and
digital camera. The wireless devices are based IEEE standard 802.11 (Collins, 2015).
Nowadays, the using of wireless devices increased day by day because these devices
do not use the physical cable that is for the purpose of communication. These devices
use the electromagnetic radiation for receive and send the data through the air, either it
is sound data or network data. These devices emit harmful radiations are affected on
human body because such radiations are present everywhere that we cannot neither
feel nor see. These radiations penetrate in our body and effect on the cell’s DNA (The
DNA is genetic material of cell that is sensitive to ionizing radiation. With the
ionizing radiation the DNA of cell can be changed (Dohle, 2010),
There are various factors responsible for the speedy developments in mobile or
wireless. Communication and the main factors are digital and RF circuit fabrication,
large scale circuit integration, portable radio equipment, smaller, cheaper, and reliable.
Digital switching techniques have made easy to use radio Communication networks
and it has bright future. May (2012).
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 Wireless Communication is the transfer of information over a distance without
using electrical conductors or wires.

The term “wireless” describes the communication in which electromagnetic waves
or RF (Radio Frequency) carry a signal over part or the entire communication path.
The main reasons for the development of the wireless Communication are:
1) Limitations of conventional mobile telephone system i.e limited service capability,
poor service performance and inefficient frequency spectrum.
2) Spectrum efficiency approach considerations should be to achieve to an ideal
mobile telephone system. This is possible using single sideband (SSB), to reuse
allocated frequency band in different geographic locations and to use spread spectrum
or frequency hopped, which generates many codes over a wide frequency band.
3) To match with latest technologies.
Wireless Communication can be via:
1) Radio frequency communication
2) Microwave communication
3) Infrared (IR) short range communication
The term “wireless” came into public use to refer to a radio receiver or transceiver.
Earlier, it was used in the field of wireless telegraphy and now a days this term is used
to describe modern wireless connections such as in cellular networks and wireless
broadband internet. (Sage 2009)
 The wireless communication devices are in the process of a global wireless
network. The development of highly reliable, miniature, solid-state radio
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frequency systems made the wireless communication system to come into
existence.
 In 1935, Edwin Armstrong demonstrated frequency modulation (FM) and since
then the FM technique is used for the mobile communication system.
The first aim on wireless was for voice and now the focus is on data. Wireless users
use the internet facility but wireless devices have limited display and inputs as
compared to fixed devices such as PC. (Setubal, &Meidanis (1997).
The “First - generation” (IG) digital wireless network in North America, used Cellular
Digital Packed Data (CDPD) and that provides 19.2 kbps data.
The “Second - generation” (2G) wireless systems are the Globals systems for Mobile
Communication (GSM). Personal Communication Service (PCS) etc. used time
division multiplexing TDMA while PCS IS-95 uses code division multiple access
(CDMA).
In third - generation (3G) wideband direct-sequence code division multiple access
(DSCDMA) is being used (Townes, 2013)
In fourth - generation (4G) digital, multimedia and high data rates is in use. Fourth generation (4G) cellular system applications need high speed data rates.
1.2 Statement of problem
Wireless communication makes use of radiation which is energy that originates from
the unstable atom, and the radiation is the form of wave particles, radiations transfer
or spread in the form of particle or wave or rays through the space. There are two
types of radiations which are ionizing and non-ionizing radiation. The non-ionizing
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radiations are directly transmit (sending and receiving) of electromagnetic radiation or
sound energy or heat energy and it does not break the chemical bond but the ionizing
radiation is composition of high energy waves that can easily remove or move the
electrons from the molecules, atoms and cause the cell damage also increase the risk
of many diseases. According to the medical test the low amount of ionizing radiation
is not much harmful, but the high amount of ionization of radiation can radiation
sickness, cause cancer etc. The DNA is genetic material of cell that is sensitive to
ionize radiation. With the ionizing radiation the DNA of cell can be changed.
Also there is time varying and multipath propagation properties.
Communicate over a medium significantly less reliable than wired physical layer.
Are unprotected from outside signals and interceptions. Multiuser interference (MUI)
is a significant problem in wireless communications. It has neither absolute nor
readily observable boundaries outside of which stations are known to be unable to
receive network frames.
1.3
Objectives of the Study
The specific objectives of this study are as follows:
1. To examine effective communication without any electrical cable
2. To access the importance of communication to man
3. To enumerate various types of communication
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1.4
Significance of the Study
A wireless local area network is a wireless computer network that links two or more
devices using wireless communication within a limited area such as a home, school,
university, computer laboratory, or office building. affirmed that WLAN or wireless
LAN is a local area network that uses radio waves as transmission
1.5
Definition of Terms
Wireless: The term “wireless” describes the communication in which electromagnetic
waves or RF(Radio Frequency) carry a signal over part or the entire communication
path
Wireless Communication: is the transfer of information over a distance without
using electrical conductors or wires.
Electromagnetic Waves Communication: The type of communication which use
electromagnetic waves as communication media for transmitting and receiving data
or voice.
Data communications (DC) is the process of using computing and communication
technologies to transfer data from one place to another, and vice versa. It enables the
movement of electronic or digital data between two or more nodes, regardless of
geographical location, technological medium or data contents.
.
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CHAPTER TWO
REVIEW OF RELATED LITERATURE
2.1 Introduction
Wireless communication was introduced in the 19th century and wireless
communication technology has developed over the subsequent years. It is one of the
most important mediums of transmission of information from one device to another
devices. In this technology, the information can be transmitted through the air without
requiring any cable or wires or other electronic conductors, by using electromagnetic
waves like IR, RF, satellite, etc. In the present day, wireless communication
technology refers to a variety of wireless communication devices and technologies
ranging from smartphones to computers, tabs, laptops, Bluetooth Technology,
printers.
2.2 Brief History of wireless communication
The history of wireless communication is discussed below.

The first telegraph was invented (1600 – 1833)

The invention of the radio from the telegraph (1867-1896)

The birth of radio (1897 – 898)

Transoceanic Communication (1901 –1909)

Voice over Radio and the First Television Transmissions (1914 – 1940)

Commercial Television and the Birth of Mobile Telephony (1946 – 1976)

Cellular Mobile Telephony and Steps toward Wireless Internet (1979 – 1994)

The Wireless Data Era (1997 – 2009)

PCS (1995-2008)
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2.3 Components of a Communication System
Figure 2.1: Communication Systems
The source originates a message, which could be a human voice, a television picture
or data. The source is converted by an input transducer into an electrical waveform
referred to as the baseband signal or message signal. Sage (2009)
The transmitter: modifies the baseband signal for efficient transmission. The
transmitter generally consists of one or more of the following subsystems: a preemphasizer, a sampler, aquantizer, a coder and a modulator.
The channel is a medium through which the transmitter output is sent, which could be
a wire, a coaxial cable, an optical fiber, or a radio link, etc. Based on the channel type,
modern communication systems are divided into two categories: wireline
communication systems and wireless communication systems.
The receiver reprocessed the signal received from the channel by undoing the signal
modifications made at the transmitter and the channel. The task of the receiver is to
extract the message from the distorted and noisy signal at the channel output. The
receiver may consist of a demodulator, a decoder, a filter, and a de-emphasizer.
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The receiver output is fed to the output transducer, which converts the electrical signal
to its original form.
Transmitters and receivers are carefully designed to overcome the distortion and
noise. The Goal of Physical layer Communication System is to transmit information
accurately and efficiently (power and spectrum).
2.4 Types of Wireless Communication
The usage of mobiles has been increased for different requirements like the internet,
talking, multimedia, gaming, photos, video capturing, etc. All these services are
available on mobile. Using wireless communication services, we can transfer data,
voice, images, videos, and many more. Carson (2007),
The different services provided by the wireless communication system is a cellular
telephone, Radio¸ paging, TV, video conferencing, etc use different communication
services, there are different wireless communications systems are developed based on
the application. Some of them are discussed below. A wireless Communication
system is classified into Simplex, Half Duplex & Full Duplex.
The simple wireless communication system is one-way communication. In this type,
the communication can be done in one direction only. The best example is the radio
broadcast system.
The half Duplex communication system is two-way communication, however, it is not
simultaneous. The best example of this type of communication is walkie – talkie.
The full Duplex communication system is also two-way communication & it is
simultaneous. The best example of this communication system is the mobile phone. In
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wireless communication, the devices which are used for communication may change
from one service to others because these are available in different shape, size & data
throughput. The region enclosed through this type of communication system is an
essential factor. Here, some of the most essential wireless communication systems are
discussed like IR wireless communication, satellite communication, broadcast radio,
Microwave radio, Bluetooth, Zigbee, etc.
2.4.1 Satellite Communication
Satellite communication is one type of self-contained wireless communication
technology, it is widely spread all over the world to allow users to stay connected
almost anywhere on the earth. When the signal (a beam of modulated microwave) is
sent near the satellite then, the satellite amplifies the signal and sent it back to the
antenna receiver which is located on the surface of the earth. Satellite communication
contains two main components like the space segment and the ground segment. The
ground segment consists of fixed or mobile transmission, reception, and ancillary
equipment and the space segment, which mainly is the satellite itself.
2.4.2 Infrared Communication
Infrared wireless communication communicates information in a device or system
through IR radiation. IR is electromagnetic energy at a wavelength that is longer than
that of red light. It is used for security control, TV remote control, and short-range
communications. In the electromagnetic spectrum, IR radiation lies between
microwaves and visible light. So, they can be used as a source of communication.
For successful infrared communication, a photo LED transmitter and a photodiode
receptor are required. The LED transmitter transmits the IR signal in the form of
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nonvisible light, that is captured and saved by the photoreceptor. So the information
between the source and the target is transferred in this way. The source and
destination can be mobile phones, TVs, security systems, laptops, etc support wireless
communication.
2.4.3 Broadcast Radio
The first wireless communication technology is open radio communication to seek out
widespread use, and it still serves a purpose nowadays. Handy multichannel radios
permit a user to speak over short distances, whereas citizen’s band and maritime
radios offer communication services for sailors. Ham radio enthusiasts share data and
function emergency communication aids throughout disasters with their powerful
broadcasting gear, and can even communicate digital information over the radio
frequency spectrum.
Mostly an audio broadcasting service, radio broadcasts sound through the air as radio
waves. The radio uses a transmitter that is used to transmit the data in the form of
radio waves to a receiving antenna(Different Types of Antennas). To broadcast
common programming, stations are associated with the radio N/W’s. The broadcast
happens either in simulcast or syndication or both. Radio broadcasting may be done
via cable FM, the net, and satellites. A broadcast sends information over long
distances at up to two megabits/Sec (AM/FM Radio).
Radio waves are electromagnetic signals, that are transmitted by an antenna. These
waves have completely different frequency segments, and you will be ready to obtain
an audio signal by changing into a frequency segment.
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For example, you can take a radio station. When the RJ says you are listening to 92.7
BIG FM, what he really means is that signals are being broadcasted at a frequency of
92.7megahertz, which successively means the transmitter at the station is periodic at a
frequency of 92.700,000 cycles/second.
When you would like to listen to 92.7 BIG FM, all you have to do is tune the radio to
just accept that specific frequency and you will receive perfect audio reception.
2.4.4 Microwave Communication
Microwave wireless communication is an effective type of communication, mainly
this transmission uses radio waves, and the wavelengths of radio waves are measured
in centimeters. In this communication, the data or information can be transfers using
two methods. One is the satellite method and another one is a terrestrial method.
Wherein satellite method, the data can be transmitted through a satellite, that orbit
22,300 miles above the earth. Stations on the earth send and receive data signals from
the satellite with a frequency ranging from 11GHz-14GHz and with a transmission
speed of 1Mbps to 10Mbps.
In the terrestrial method, in which two microwave towers with a clear line of sight
between them are used, ensuring no obstacles to disrupt the line of sight. So it is used
often for the purpose of privacy. The frequency range of the terrestrial system is
typically 4GHz-6GHz and with a transmission speed is usually 1Mbps to 10Mbps.
The main disadvantage of microwave signals is, they can be affected by bad weather,
especially rain. Please refer to this link to know more about Microwaves – Basics,
Applications and Effects
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2.4.5 Wi-Fi
Wi-Fi is a low power wireless communication, that is used by various electronic
devices like smartphones, laptops, etc.In this setup, a router works as a
communication hub wirelessly. These networks allow users to connect only within
close proximity to a router. WiFi is very common in networking applications which
affords portability wirelessly. These networks need to be protected with passwords for
the purpose of security, otherwise, it will access by others
2.4.6 Mobile Communication Systems
The advancement of mobile networks is enumerated by generations. Many users
communicate across a single frequency band through mobile phones. Cellular and
cordless phones are two examples of devices that make use of wireless signals.
Typically, cell phones have a larger range of networks to provide coverage. But,
Cordless phones have a limited range. Similar to GPS devices, some phones make use
of signals from satellites to communicate.
2.4.7 Bluetooth Technology
The main function of Bluetooth technology is that permits you to connect various
electronic devices wirelessly to a system for the transferring of data. Cell phones are
connected to hands-free earphones, mouse, wireless keyboard. By using the Bluetooth
device the information from one device to another device. This technology has various
functions and it is used commonly in the wireless communication market.
2.4.8 Global Positioning System (GPS)
In satellite communication, GPS or global positioning system is a subcategory. This
kind of system is used to help by providing different wireless services such as speed,
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location, navigation, positioning using satellites, and GPS receivers. Please refer to
this link to know more about the Global Positioning System.
2.4.9 Paging
A paging system allows one-way communication to a huge audience. Apart from the
broadcast source, this kind of paging system allows the speaker to give clear,
amplified commands throughout a capacity. When the employee of paging
communicates through a telephone then the message will be broadcasted throughout
the speakers of the system. After that, messages can also be recorded.
There are many benefits by using this type of communication system like the
following.

E-mails are frequently ignored otherwise recorded through spam blockers.

Mass texts mostly lie on a telephone network.

This system is wired into the infrastructure of the building that allows consistent
mass communication.

Systems of speakers make sure that a message converses with each region of a
building concurrently. It’s also achievable to transmit pages to exact building
“zones” if required.

Another advantage of this paging system is that no dedicated broadcast device is
necessary. An employee can just lift the phone, choose the paging system &
broadcast the whole building.
2.4.10 Radar
Radar is an electromagnetic sensor or detection system used to track, locate, detect &
and identify objects of different types at significant distances. The operation of this
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detection system can be done by sending electromagnetic energy in the direction of
objects, usually called targets, which observes the echoes. Here the targets may be
ships, astronomical bodies, aircraft, spacecraft, automotive vehicles, insects, etc.
2.4.11 Radio Frequency Identification
Radio Frequency Identification (RFID) is one kind of wireless communication that
uses electrostatic coupling otherwise electromagnetic in the RF portion of the
electromagnetic spectrum to exclusively identify a person, object & animal. It is used
in manufacturing, healthcare, shipping, home use, retail sales, inventory management,
etc.
RFID & barcode technology are used in related methods to track inventory, however,
three significant differences will make everyone a better choice in certain
circumstances. In real-time, the data which is stored within the RFID tag can be
updated. Indifference, the data in the bar code is read-only & cannot be altered. RFID
tags need a power source whereas the bar codes simply need the technology to read
the bar code to include a power source. (Carpenter, 2013)
2.5 Benefits of Wireless Communication
1.
Anywhere,
Anytime
Work:-
Working
professionals
through
wireless
communication can access the internet and mobile anywhere, anytime without any
problem of wire and cables.
2. Enhanced Productivity:- Wired internet or dialup connectivity increases the cost,
whereas using wireless internet not only reduces the cost but also it is possible for a
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student or any person to complete an assignment or work at any time. The ultimately
improves Productivity.
3. Remote Area Connectivity:- Wireless Communication makes possible for the
doctors, engineers and other professionals working in remote areas to keep in touch
with each other.
4. On Demand Entertainment:- Persons who are unable to space time from their
busy working schedule can have reality programs, online TV shows and internet
surfing or download activities on their demand anytime.
5. Emergency Alerts:- It is possible to address emergency situations quickly through
wireless communication. With the help of wireless communication help and assistance
can reach the affected areas in emergency and crisis situation.
6. Accelerated Bussiness Process:- Wireless Communication can increase the
number of sales opportunities. A single sale person can meet sale goals successfully.
7. Industrial Use:- Specialised mobile radio and land line mobile radio can be used in
certain industrial situations for the safety.
8. Worldwide Connectivity:- Wireless Communication is the best technology to
connect billions of people worldwide.
9. Multiple Usage And Low Interference:- Cell handsets can continuously change
frequencies as per the requirement. Multiple Usage and low Interference rates are
achieved through the use of low power transmitters.
10.Device Mobility:- In the wireless communication there is Mobility of the devices
with in the environment. It is a simple matter to add or remove a device from the
system without any disturbance to the remaining devices.
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11.Easier Transmission:- Data transmission is easier in wireless communication.
12.Cost:- Setting up the cell sites and the cost of running and maintaining a wireless
based communication is very less as compared to the Wired communication system.
Agarwal, (1991)
13.Other
Features/Benefits:-
Internet
Surfing, high speed
Wi-Fi system,
downloading activities, live TV shows, matches etc. are available on one device with
wireless communication.
2.6. Advantages of wireless Communication:
As compared with wired systems, wireless communication systems have several
benefits. The advantages of wireless communication include the following
1. Freedom from wires: Can be configured with the use of any physical
connection.
2. Easy to setup: Wireless network is easy to expand and setup
3. Better or global coverage: It provides global reach by providing networking in
places such as rural areas, battlefields, etc… where wiring is not feasible.
4. Flexibility: Wireless network is more flexible and adaptable compared to a wired
network.
5. Cost-effectiveness: Since it is easy to install and doesn’t require cables, the
wireless network is relatively cheaper.
6. Mobile and portable: Wireless network is easy to carry and re-install in another
place.
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.Price: The price of fixing cables, wires & other communications can be reduced
within wireless communication. Therefore the total cost of the system can be reduced
as evaluated with wired communication. Fixing a wired network within a building,
digging up the soil to place the cables to run those wires across the roads is a very
hard, expensive, and time taking task.
In old constructions, making holes to fix the cables is not a good idea because it
demolishes the integrity as well as the significance of the building. In addition, in
older constructions with no committed shape for communication, Wi-Fi otherwise
WLAN is the single option.
Mobility: As previously mentioned, mobility is the major benefit of this
communication system. It gives the liberty to go around when it is still connected to
the system.
Simple Installation: The system & fitting of equipment in wireless communication
network & communications is extremely simple because we shouldn’t be anxious
regarding the irritate of cables. In addition, the time necessary to connect a wireless
system very less as compared with a full cable-based network.
Consistency: In wireless communication, there is no involvement of wires and cables
so communication failure is not happened because of the harm of these cables which
may be caused based on the ecological conditions, normal reduction of metallic
conductors, and splice of cable.
Tragedy Recovery: When fire accidents, disasters, or floods occur, then the loss of
communication in the system can be negligible.

Any data or information can be transmitted faster and with a high speed
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
Maintenance and installation is less cost for these networks.

The internet can be accessed from anywhere wirelessly
It is very helpful for workers, doctors working in remote areas as they can be in touch
with medical centers. (Boyce, 2015)
2.7 Disadvantages of wireless communication
Wireless
communication
has
some
drawbacks
as
compared
with
wired
communication. The disadvantages of wireless communication include health,
security, and interference.
Interference: In a wireless communication system, the signals can be transmitted by
using open space like the medium. So, there is a chance of interfacing the radio
signals from one network to other networks like Bluetooth and WLAN. These
technologies utilize the 2.4GHz frequency to communicate when they are active as
well as; there is a chance of intrusion.
Safety: Security is the main concern in the wireless communication system because
when the signals are broadcasted within open space, then there is a chance of
interrupting the signals & copy sensitive data.
Health Concerns: Exposure to any kind of radiation continuously can cause health
issues. Although, the RF energy range can cause injure are not exactly recognized, it
is informed to keep away from RF radiation to the most.

An unauthorized person can easily capture the wireless signals which spread
through the air.

It is very important to secure the wireless network so that the information cannot be
misused by unauthorized users
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2.8 Generation of Wireless Communication
The different generations of wireless communication include the following.

1st Generation (1G)

2nd Generation (2G)

3rd Generation (3G)

4th Generation (4G)

5th Generation (5G)
2.9 Applications of Wireless Communication
Applications of wireless communication involve security systems, television remote
control, Wi-Fi, Cell phones, wireless power transfer, computer interface devices, and
various wireless communication-based projects.
Wireless Communication Based Projects
Wireless communication-based projects mainly include different types of wireless
communication technologies like Bluetooth, GPS, GSM, RFID, and Zigbee projects
which are listed below.

Android Based Smart Phone Used for Induction Motor Control

Smart Phone Controlled Traffic Signal Override with Density Sensing System

Arduino based Home Automation

Phone Controlled-Load Management System

Robotic Vehicle Movement By Cell Phone

Dialed Telephone Number LED Based Display System

DTMF based Load Control System

Dedicated Message Communication Wirelessly between Two Computers

Wireless Message Communication between Two Computers

Android-based Remotely Programmable Sequential Load Operation
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
Remotely Controlled Android based Electronic Notice Board

Remote Operated Domestic Appliances Control by Android Application

Remote Password Operated Security Control by Android Applications

Home Automation by Android Application based Remote Control
Therefore, this is all about Types of wireless communication, these networks are one
of the important technologies in the telecommunications market. WiFi, WiMax,
Bluetooth, Femtocell, 3G, and 4G are some of the most important standards of
Wireless technology. The information which is given in this article will be helpful to
the viewers. Furthermore, for any queries, suggestions, or electronics projects, you can
comment on us by commenting in the comment section below. Here is a question for
you “What are the Advanced Technologies in Types of Wireless Communication?”
Other applications are:
1. Satellite system
2. Television remote control
3. Wi-Fi
4. Paging system
5. Wi-Max
6. Security systems
7. Cellphones
8. Computer interface devices
9. Bluetooth
10. GPS
11. GSM
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CHAPTER THREE
SUMMARY, CONCLUSION AND RECOMMENDATIONS
3.1 Summary
In the present days, the wireless communication system has become an essential part
of various types of wireless communication devices, that permits the user to
communicate even from remote operated areas. There are different types of wireless
communication
devices
like
mobiles.
Cordless
telephones, Zigbee
wireless
technology, GPS, Wi-Fi, satellite television, and wireless computer parts. Current
wireless phones include 3 and 4G networks, Bluetooth, and Wi-Fi technologies.
3.2 Conclusion
The main benefit of wireless communication is mobility. This kind of communication
provides flexibility and very easy to use excepting mobility. For instance, mobile
telephony can be implemented anytime and anyplace through significantly high
throughput performance.
One more point is its infrastructure because, for the wired communication systems, the
fitting of infrastructure is a costly & time taking task whereas the installation of
wireless communication infrastructure is very simple and less cost.
from the above information, finally, we can conclude that in remote areas as well as
emergency situations, the wired communication setup is not easy but wireless
communication is a possible choice. There are many reasons to employ wireless
communication like liberty from wires, global coverage, flexibility & stay connected.
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3.3 Recommendations
wireless devices emit radiations are harmful to human health so there are some
recommendations that one should use one’s cell phone when it is necessary.
Each and every one should know about the effects of these wireless radiations on
human body, in this regard public awareness programs may be designed and
executed as soon as possible by the concerned authorities.
Government should take an action on cell phone towers existing in or near
populated areas because cell phone towers emit the harmful radio waves which
are a cause of human health problems.
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