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UNIT 4 Data Communication. MC

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UNIT 4 Data Communication
4.1 Mobile Computing
Lead-in. In small groups discuss what features do you use on a mobile device (e.g. GPS,
maps, camera, pm3)? What do you them for?
Task 1. Warm up. a) Think about people in these jobs. Brainstorm how might a mobile device
be useful to them?
a delivery driver
an smm specialist
a real estate agent
b) Gather your ideas about each person from the table and put them in correct order in a stepby-step manner. Do the algorithms of people from different professions look similar?
Task 2. Vocabulary. Read the advertisement and find words in the text that match the
definitions.
1 change stg to make it suit a special purpose ___________________
2 add electronic information to stg, e.g. a photo ___________________
3 the position of stg ___________________
4 changing written or printed words to data that a computer can understand ______________
5 give information ____________________
6 a word used to show that stg is completely correct or true _______________
7 stored information, e.g. on a computer ________________
8 a small part inside smartphones and other devices that measures change of speed, e.g. if
someone drops it ______________
Task 3. Communication. Work in pairs. Talk to your partner about how are these mobile
device features and functions useful. Make 3 sentences for each by using 0 and 1st
conditionals, e.g. If the phone has a GPS, we can share our location when necessary…
camera Google
products
GPS
security system
torch
PlayMarket
scanner
explorer
fingerprint sensor
games
Task 4. Reading. Read the text about MC features and complete the following tasks.
Mobile Computing Features
Mobile Devices
The first semblance of mobile computing for old-timers was Laptop due to its little bit
of mobility across desks and offices though connected by wire. The mobile evolution
continued with the invention of slimmer and easily portable end-user compute devices like a
walkie-talkie, pager, Data assistants, Tablet computers like iPad/ Tablet, and finally merging
of Phone and computers as smartphones.
Features of the devices are:
• The size should be as small as possible to carry it easily where ever one goes, and the
weight should be as minimum as possible.
• It should have sufficient processing power to churn out numbers fast.
• Should support all communication protocols
• It should support all networks and should work anywhere in the globe without any network
glitch
• Display should be very clear and responsive to environmental changes
• Battery should have a long life as much as possible
• It should support Near Field communicator (NFC) protocol to emit signals to nearby devices
for completing payment transactions as a replacement to Debit/ Credit cards.
• It should have sufficient storage space
• Should have a modern camera to take photos and interface them with applications
seamlessly.
• It should have finger print sensor to incorporate secured locking features
• Should have fast charging facility
Communication Protocols
Mobile computing uses wireless network protocols mostly to connect to external
networks and devices, and it uses a spectrum of radio waves in the communication.
These protocols deploy the multiplexing technique which combines digital signals
with analog signals in a channel before sending it and demultiplexes at the destination.
Multiplexing optimizes the utilization of scarce resources.
Each user is allotted a different frequency in Frequency division multiplexing
(FDMA) and users share frequency in Time-division Multiplexing (TDMA), and in Code
Division Multiplexing (CDMA), users share the same frequency but identified by a unique
code.
Global System of Mobile communication (GSM) was one of the most adopted
wireless systems in the 1980s. It uses TDMA protocol and it helped in popularising mobile
telephones to a large extent. Wireless local loop (WLL) provided telephone services in a local
area, and it had a base system and handsets for voice communication.
General Packet Radio Services (GPRS) transmitted the voice data over the network
in packets. Users paid only for the volume of data transmitted not for the usage time.
First-generation (1G) mobile communication that used analog signals to transmit
data was introduced in the 1980s in the US. The lacunae in 1G was low-speed 2.4kbps,
inferior quality of voice transmission, and a bulky phone with low battery life.
Second generation (2G) mobile communication used digital signal over GSM
technology improved voice quality and improved the speed up to 64kps and enabled
messaging. 2G had several security issues.
3G offered speed upto 2Mbps and enabled internet browsing, audio/video file
transfer, Email services, and games. It paved the way for merging data technologies with
telephony systems and enabled everything in mobile and mobile-first concepts.
4G improved the mobile user experience to the peak level and it achieved the speed
of 1Gbps. It enabled HD TV with live streaming, cloud computing, telephone on the data
network, etc.
Wireless network
Mobile devices use voice and data network services offered by the telecom service
provider. Users utilize the data services provided by Telcom operators and get into the
internet and do whatever they want. The only disadvantage in this service is the bandwidth of
the data network is limited, and users cannot download large files and refrain from using dataintensive applications.
Mobile devices can be used as desktops, laptops, and connected to the Local area
network or Wide area network of any organization through wireless connection and continue
to do normal activities. These devices can be connected to the internet thru local Wi-fi
networks in the home or in a public place.
Global Positioning System (GPS)
Mobile devices are capable of availing the satellite services to know its current location.
Though the internet is not involved for GPS location services, it added a lot of extra features
in enabling unique services offered to the users such as:
• Integration with Maps to know the current position pictorially
• Navigational applications to know the routes to a place.
• Taxi and other Delivery services to reach your locations
• Location-based contextual information access
Mobile software
Mobile devices vary in size, and it was a challenge to develop programs to display
content matching the size. Responsive web design facility offered by several application
platforms resolved this issue.
Another issue in this software development is that too much content had to be
displayed in a too little place and get the attention of the users quickly. It is addressed by
using innovative methods of simple web design.
Developers need to manage the security concerns and take care of any breaches at
the coding stage itself.
(resource: https://www.educba.com/mobile-computing-features/ )
a) Answer the questions:
How the existence of a Laptop impacted on creating first mobile devices?
How would you rate the classification of mobile devices’ features?
Why does mobile computing use wireless network protocols?
What’s the difference between CDMA and GSM?
How do mobile devices use voice and data network services?
What advantages does GPS provide the consumers?
What are the main issues of the software development?
b) Complete the table. Write the definition of the following terms in your own words:
Term
Definition
1. pager (n)
2. communication protocols (n)
3. Near Field communicator (n)
4. fingerprint sensor (n)
5. analog signals (n)
6. Wireless local loop (phrase)
7. voice transmission (n)
8. merge (v)
9. cloud computing (n)
10. display content (n)
c) Write a mini-paragraph in 100-150 words describing which features and functions of
a mobile device would you like to be improved and explain why.
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