Sending and receiving devices

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Term 2, 2011
Week 1
CONTENTS
• Sending and receiving devices
• Mobile devices connected to networks
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Smart phones
Personal digital assistants
Hand-held computers
Netbook
Portable media players
Navigation systems
Digital cameras
• Questions
• Initiate or accept the transmission of data, instructions
and information.
• Notebook and desktop computers, TabletPCs,
midrange servers and mainframe computers can all
serve as sending and receiving devices.
• Can communicate directly with another computer, with
hundreds of computers on a company network or with
millions of computers on the internet.
• A web-enabled hand-held device also serves as a
sending and receiving device. Provides access to the
internet and email from any location.
• Usually small enough to fit in a pocket.
Devices store programs and data permanently
on memory inside the unit or on a flash
memory card. Usually able to be connected to
a personal computer.
• A number of mobile devices can be connected
to the internet wirelessly allowing users to
chat, send messages, email and access
websites.
Smart phones
• Allows users to send emails and access the Web.
Replacing Notebook computers for many
business people due to them being lightweight
and convenient.
• Communicate wirelessly with other devices or
computers. Can function as a portable media
player and a digital camera.
• Often include applications software (i.e.
Spreadsheets, word processors).
• Design of smart phones vary.
• Have some limitations: small screens decrease
amount of information which can be displayed at
once, small keyboard affects ability to correctly
enter data.
• These limitations can be overcome to a degree.
Most websites offer a simplified version of the
page so it can be viewed on a smart phone, and
smart phones often use auto-correct
applications.
• Most can directly connect to Bluetooth-enabled
devices.
• The increasing popularity of these devices cause
an increase of traffic on networks.
Personal digital assistants
• Personal digital assistant (PDA) originally featured
personal management tools (i.e. Calendar,
appointment diary, calculator, address book).
Now include application software.
• Usually use a stylus but can also contain mini
keyboard.
• Limitations include: small screen size, limited
battery life, limited memory to run applications.
• Becoming difficult to distinguish between PDA’s
and smart phones due to both being used for
similar functions.
Hand-held computers
• Small enough to fit in the hand.
• Communicate wirelessly with other computers
and devices. Many have mini/specialised
keyboards.
• Often used by people who need to record
data as they travel (i.e. Electricity and water
meter readers).
Netbook
• Does not have all the features of a notebook computer.
• Weighs about 1.4 kg, 25cm screen and a QWERTY keyboard
which is 80-90% the size of a standard keyboard.
• Some have hard-disk drive, others use a solid-state flash
memory drive.
• Flash memory is robust and less likely to suffer mechanical
breakdown. However, more expensive and can slow
computer.
• Do not include an optical drive which ensures they remain
small.
• Lack a graphics card, therefore video performance can be
poor.
• Processor commonly has a speed of 1.66 GHz, compared to
Notebook speed of 2.4 GHz.
Portable media players
• Stores, organises and plays digital media.
• Usually connects to a computer from which
the media is downloaded. Can include music,
video, movies and photos.
• Can be touch screen, and some media players
are web-enabled.
Navigation systems
• The global positioning system (GPS) is a
navigation system made up of at least 24
satellites that communicate with a device (fixed
or portable) in a car or other vehicle.
• Able to pinpoint the car’s location to within 50
metres, receives 3D data (latitude, longitude,
altitude), and precise time. The car’s position is
then overlaid with digital mapping.
• The device then provides directions as well as
locations of petrol stations etc.
• Many phones now include GPS.
Digital cameras
• Photos are taken and stored digitally on a
memory card.
• Can view photos, delete or upload to
computer (usually via a cable or memory card
reader on computer).
• Many smart phones and PDA’s come with
digital cameras.
Questions
• What does web-enabled mean? What devices
come with this capability?
• What functions are available on a smart phone?
• Briefly compare a Notebook to a Netbook. What
the pros and cons of each?
• Research and explain (in your own words) what
the term ‘technological convergence’ refers to.
Provide an example of a sending and receiving
device that technological convergence applies to.
What are the advantages of this? Are there
disadvantages?
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