Wireless Communication

and
Mobile Computing

By
Tekalign B.
Chapter Two
Mobile Computing

Lecture 2: Mobile Computing 10/25/2023

 Mobile Computing
3

 A simple definition could be:

• Mobile Computing is using a computer (of one kind or
another) while on the move.
 Another definition could be:
• Mobile Computing is when a work process is moved from a
normal fixed position to a more dynamic position
 A third definition could be:
• Mobile Computing is when a work process is carried out
somewhere where it was not previously possible
• Mobile Computing is an umbrella term used to describe
technologies that enable people to access services anytime
and anywhere
Lecture 2: Mobile Computing 10/25/2023
 Mobile Computing
4

Mobile computing systems

• are computing systems that may be easily moved physically and
whose computing capabilities may be used while they are being
moved.

• Involves:
 Mobile devices ( like laptops, personal digital assistants (PDAs) and
Smart phones)
 And a wireless network connection based on Wi-Fi or cellular
wireless technology, such as 5G.

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• How to distinguish mobile computing systems from other

computing systems?
• we can identify the distinctions in
 the tasks that they are designed to perform,

 the way that they are designed, and

 the way in which they are operated.

Lecture 2: Mobile Computing 10/25/2023

 History of Mobile Computing
6

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 Cont’d…
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• One of the very first computing machines, the abacus, which

was used as far back as 500 B.C., was, in effect, a mobile computing
system because of its small size and portability.
• Most calculators today are made with an entire slew of
mathematical functions while retaining their small size and
portability.
• The abacus and calculators became important parts of technology
not only because of their ability to compute but also because of
their ease of use and portability.
• A mobile computing system, as with any other type of computing
system, can be connected to a network. Connectivity to the
network, however, is not a prerequisite for being a mobile
computing system.
Lecture 2: Mobile Computing 10/25/2023
 Why Mobile Computing?
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Lecture 2: Mobile Computing 10/25/2023

 Why Mobile Computing?
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Lecture 2: Mobile Computing 10/25/2023

 Principles of Mobile Computing
10 (Evolution)

 Mobile computing can be categorized into seven major

categories of focus

 These categories are the basis for the technology that is used today
in research and design of mobile computing

 Each category or section is a different area that was focused on

making mobile computing what it is today

 These seven categories are: Portability, Miniaturization,

Connectivity, Convergence, Divergence, Apps, Digital
Ecosystems
Lecture 2: Mobile Computing 10/25/2023
 1. Portability
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 2. Miniaturization
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 3. Connectivity
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 4. Convergence
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 5. Divergence
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 6. Applications (Apps)
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 7. Digital Ecosystem
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 Example: Smartphone
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 2.2. Mobile Devices and Mobile OS
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 What are types of mobile computing?
20
 Mobile computing is a combination of infrastructure, hardware and software
technology.
1. Mobile infrastructure. Technical pieces that allow devices to
communicate. Mobile infrastructure includes the wireless protocols
(IEEE802.11).

2. Mobile hardware. The physical mobile device and supporting hardware

that users interact with make up the mobile hardware. This may include cell
phones, laptops, tablets, wearable computers and accompanying chargers
and accessories.

3. Mobile software. This refers to the applications that run on mobile

devices, including mobile operating systems (OSes) and user-facing
applications, such as mobile browsers and e-commerce applications.
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Mobile Hardware
 Includes mobile devices or device components that receive or access the
service of mobility.
 They would range from portable laptops, smartphones, tablet Pc's, Personal
Digital Assistants.
 These devices will have a receptor medium that is capable of sensing and
receiving signals.

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Mobile Software
 Is the actual program that runs on the mobile hardware.

 A Mobile operating system, also known as a Mobile OS, a Mobile platform,

or a handheld operating system, is the operating system that controls a
mobile device similar in principle to an operating system such as Linux or
Windows that controls a desktop computer

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 Below is the list of most common operating systems (OS)

found on smartphones and its manufacturers.
 Symbian OS – Nokia’s Cell Phone operating system

 Android OS – Google’s free, open-source cell phone operating

system

 iPhone OS (iOS ) – Apple’s mobile operating system

 BlackBerry OS – Proprietary mobile operating system, developed

by Research In Motion for its BlackBerry

 Windows Phone 7 ( Windows Mobile ) – Mobile operating system

developed by Microsoft Lecture 2: Mobile Computing 10/25/2023
 2.3. Mobile Computing Issues and Challenges
24

 Due to technology growth distances become short,

communication becomes easy, data transfer is enriched, but there
are so many issues and challenges in the domain that need to be
researched and addressed to make mobile computing more secure,
robust and reliable.

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Some important mobile computing issues

Low bandwidth

 Mobile internet access is slower than the fixed desktop

connection while using GSM and other advanced technologies
such as 3G, 4G, and 5G.

 Local wireless connection offers Mbit/s of speed and wide

wireless connection offers only Kbit/s of speed.

 There is a requirement of using more bandwidth while using such

advanced mobile technologies so that the user can transfer data at a
higher speed while the user is mobile Lecture 2: Mobile Computing 10/25/2023
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Lower security
 When working with mobile people are completely dependent on
the public network which can be easily tracked and hacked by
hackers.
 There is a big problem with the security of data while transferring
from one mobile device to another device. Therefore to protect
the data from eavesdropping there is a need for strongly secured
algorithms of authentication and security.
 Money transaction is a very sensitive area and it is the target on the
hackers. Internet frauds related to money are huge.
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Transmission interferences
 Radio transmission cannot be protected therefore there is higher
transmission interference due to electric engines, lightening, high
buildings, mountains, weather conditions, etc., all this results in a higher
loss of data rate and bit errors.

Shared medium
 Radio access is a shared medium because it is just impossible to give
dedicated radio access to all the users.
 However, different techniques are deployed still so many questions are
unanswered such as how to provide quality of service to each user
sharing radio access.
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Ad-hoc networking
 Wireless and mobile computing allow ad-hoc networking without a prior set of
infrastructure between senders and receivers.
 This creates several challenges and issues before the network administration
such as the reliable and secure connections between sources to destination.
 Dynamic topology again a challenging issue for a reliable connection from
one point to another point.

High delays, large delay variation

 A serious problem faced by Internet protocols is variations in link characteristics.
In wireless transmission delays of various seconds occur that create so many
problems in transmission and communication.

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Power consumption

 When a power supply is not available mobile devices totally depend

on battery power. There is a need to use some resources that can
provide power supply at a cheaper cost and with ease.

Lecture 2: Mobile Computing 10/25/2023

 2.4. Mobile Computing Technologies
30

 Mobile technology is technology that goes where the user goes.

 It consists of portable two-way communications devices,
computing devices and the networking technology that connects
them.

 Currently, mobile technology is typified by internet-enabled devices

like smartphones, tablets and watches.

 These are the latest in a progression that includes two-way pagers,

notebook computers, mobile telephones (flip phones), GPS-

navigation devices and more.

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Types of Mobile computing Technologies

 Followings are the few famous mobile technologies:

 SMS

 MMS

 4G

 3G

 GSM

 CDMA

 Wi-Fi
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 SMS: “SMS” stands for “Short Message Service.” It is now the most
widely used and oldest text messaging service. SMS are also sent over
cellular networks, therefore you’ll need a wireless plan and a wireless
carrier. SMS is fast gaining popularity in the world as a low-cost
messaging medium.

 MMS: MMS (Multimedia Messaging Service) messaging is a

standard method of delivering multimedia material, including messages.
MMS, as opposed to SMS, can send up to forty seconds of video, one
picture, a multi-image slideshow, or audio. MMS texting will be supported
by the majority of contemporary devices.
Lecture 2: Mobile Computing 10/25/2023
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 3G: The third letter in the designation 3G stands for third-generation
access technology, which allows mobile phones to connect to the internet.
Every new technology introduces new frequency bands and data
transmission rates.
 4G: The fourth generation of mobile networking technology is known as
4G, which comes after the 2G and 3G networks. Although it’s commonly
referred to as 4G LTE, this isn’t exactly right because LTE is just one
sort of 4G.
 Global System for Mobile technology: The (GSM) is an acronym
for Global System for Mobile Communication. GSM is a cellular
technology that is open and digital and is used for mobile
communication.
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 Wi-Fi (Wireless Fidelity): Wi-Fi is a wireless networking

technology that allows us to connect to a network or to other
computers or mobile devices across a wireless channel.

 Code Division Multiple Access: (CDMA) is an acronym for

code division multiple access. It is a channel access mechanism that
also serves as an example of multiple access. Multiple access
simply means that data from multiple transmitters can be delivered
onto a single communication channel at the same time

Lecture 2: Mobile Computing 10/25/2023

 2.5. Advantages and Limitations of Mobile
35 Computing

Advantages of mobile computing

 Portability
 small and light enough to be carried or moved easily, and not attached by
electric wires

 Affordability
 Mobile computing devices are becoming cheaper and offer more capabilities.

 Data Access
 Mobile devices and applications enable companies to collect more consumer
data than was possible with traditional computing.
 For example, mobile devices can record geolocation of the device and its user.
Lecture 2: Mobile Computing 10/25/2023
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Advantages of mobile computing …

 Increased Productivity
 People can work from their homes at any and all times.
 They have access to large amounts of information and can teach themselves
anything and do anything.

 Entertainment
 Access to a wide variety of movies, educational and informative
content is now simple.

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Limitations of mobile computing

 Security
 Keeping a device constantly connected to the internet makes it
vulnerable to threats.
 Issues with Connectivity
 Mobile devices need either WiFi connectivity or mobile network
connectivity to access most of their capabilities.

 Device Size Limitations

 The portability of mobile computing devices demands smaller sizes.
 And the limitations in size puts limitations on features like processing power,
storage, and screen resolution.
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Limitations of mobile computing…

 Power Consumption
 Rechargeable batteries are always limited by the time it needs before it needs
to be plugged in.
 Insufficient Bandwidth
 Mobile Internet access is generally slower than direct cable
connections, using technologies such as GPRS and EDGE, and more
recently 3G and 4G networks.
 Transmission Interference
 Weather, and the range from the nearest signal point can all interfere
with signal reception.
 Reception in tunnels, some buildings, and rural areas is often poor.
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Limitations of mobile computing…

 Potential Health Hazards
 People who use mobile devices while driving are often distracted
from driving are thus assumed more likely to be involved in traffic
accidents.

Lecture 2: Mobile Computing 10/25/2023

 2.6. Mobile Computing Applications
40

 Although many applications can benefit from wireless networks and

mobile communications, particular application environments seem to be
predestined for their use. The following sections will enumerate some of
them – it is left to you to imagine more.

1. Vehicles
 In near future cars will comprise many wireless communication systems
and mobility aware applications.
 For personal communication, a universal mobile telecommunications
system (UMTS) phone might be available offering voice and data
connectivity with 384 kbit/s.
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 For remote areas, satellite communication can be used, while the current
position of the car is determined via the global positioning system (GPS).
 Cars driving in the same area build a local ad-hoc network for the fast exchange
of information in emergency situations or to help each other keep a safe
distance. Satellite communication links can also be used.
 Networks with a fixed infrastructure like cellular phones (GSM, UMTS) will be
interconnected with trunked radio systems (TETRA) and wireless LANs
(WLAN).
 Wireless networks inside a car can comprise personal digital assistants (PDA),
laptops, or mobile phones, e.g., connected with each other using the Bluetooth
technology.

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2. Emergencies
 Just imagine the possibilities of an ambulance with a high-quality wireless
connection to a hospital.
 Vital information about injured persons can be sent to the hospital from the
scene of the accident.
 All the necessary steps for this particular type of accident can be prepared and
specialists can be consulted for an early diagnosis.
 Wireless networks are the only means of communication in the case of natural
disasters such as hurricanes or earthquakes.
 In the worst cases, only decentralized, wireless ad-hoc (The network is ad
hoc because it does not rely on a pre-existing infrastructure) networks survive.
 The breakdown of all cabling not only implies the failure of the standard wired
telephone system, but also the crash of all mobile phone systems requiring base
stations!
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3. Business
 Managers can use mobile computers say, critical presentations to
major customers.
 They can access the latest market share information.
 To enable the company to keep track of all activities of their
travelling employees, to keep databases consistent etc.
 With wireless access, the laptop can be turned into a true mobile
office, but efficient and powerful synchronization mechanisms are
needed to ensure data consistency.

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4. Infotainment
 Now a days there is a huge market of Entertainment for
humans while they are on move.
 Watching movies, listening music and playing a game is become a
part of life for entertainment.
 In this case mobile computing performs a major role to provide
uninterrupted internet connection to digital devices.

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5. Replacement of wired networks
 In some cases, wireless networks can also be used to replace
wired networks, e.g., remote sensors, for tradeshows, or in
historic buildings.
 Due to economic reasons, it is often impossible to wire remote
sensors for weather forecasts, earthquake detection, or to provide
environmental information.
 Wireless connections, e.g., via satellite, can help in this situation.
 Wireless access points in a corner of the room can represent a
solution.

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 There can be other more applications and services for the

mobile computing, few of the possible mobile applications &
services are listed below:

1. Personal 2. Telebanking 3. Perishable

4. E governance 5. Transaction oriented 6. Tourism

7. GPS based systems 8. Entertainment 9. Remote monitoring

10. News 11. Maps/navigation guide 12. M shopping

13. Education 14. credit card verification

Lecture 2: Mobile Computing 10/25/2023
End of Chapter Two

Lecture 1: An Overview of Wireless Communication Systems 10/25/2023