Green Computing
Mobile Phones
and Applications
Maziar Goudarzi
Outline
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Significance of mobile phones
Mobile phone internals
Cellular phone infrastructure
Major points of energy consumption
Greener life by mobile phones
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History
• Analog Cellular Networks – 0G, 1G
– 0G: 1947, ATT
• UHF-VHF Frequencies
– 1G: 1978, AMPS
• FDMA
• Digital cellular networks – 2G
– 1990, Finland
– Europe: GSM
– USA: CDMA
Two 1991 GSM mobile phones
with several AC adapters
History (cont’d)
• 2G extensions – 2.5G
– 2G + data service
– CDMA2000 1x, GPRS, EDGE
• Mobile broadband data – 3G
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Demand for data service
Packet switching instead of circuit switching
Various standards, hard to converge
2 Mbit/s maximum data rate indoors, 384 kbit/s outdoors
1st pre-commercial: NTT DoCoMo, Japan May 2001
Mobile internet, Dongles
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History (cont’d)
• Higher speed data – 3.5G, 3G+, Turbo 3G
– High-Speed Downlink Packet Access (HSDPA)
– Down-link speeds of 1.8, 3.6, 7.2 and 14.0 Mbit/s
• Native IP networks – 4G
– 2009: Bandwidth-intensive applications
• E.g. streaming media
• 3G networks would be overwhelmed
– Data optimized technologies
– WiMax in US, LTE in Scandinavia
Further reading: http://en.wikipedia.org/wiki/History_of_mobile_phones
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Basic Operation of Cell Phones
Half-duplex radio
• Half duplex
• Walkie-talkie
• CB: Citizen Band Radio
Full-duplex radio
• Full duplex
• Cell phones
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Basic Operation of Cell Phones
Old Style: Central Radio Tower
• One tower per town
• Limited channels (25)
available
• Powerful radios needed
• Limited number of
simultaneous talkers
• Walkie Talkie: 1 channel
• CB: 40 channels
Cellular Networks
• Share frequencies across cells
• Cell phones: 1664+ channels
Cell Phone Internals
Disassembled Cell Phone
Mechanical Parts
http://techon.nikkeibp.co.jp/article/
HONSHI/20080226/148031/
P905i Main Board
The baseband processing IC is single-packaged into a package-on-package (PoP) with the 10
application processor
W53H Main Board
920SH Main Board
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Cell Phone Components
Main components
• Baseband processor
• Application processor
• Power supply
• Keyboard and display
controllers
• Camera/GPS/WiFi/etc.
• Power supply unit
• Various connectors
http://electronics.howstuffworks.com/inside-cell-phone.htm
The microprocessor (Ericsson phones use an ASIC
version of the Z-80)
An Interesting Project
Cell Phone Implant
• 2002: Royal college of Art,
London
• Vibration transmitted from
tooth to inner air
• Participants confirmed to hear
crystal clear voices through
teeth!
• Got people think about
implantable phone technology
http://electronics.howstuffworks.com/cell-phoneimplant.htm
Smart Phones
What is it?
• Between normal phone and
PDA
• Install applications
• Additional features
– Accelerometer
– Proximity sensor
– Ambient light sensor
• Software stack
– OS (Android, iOS, Windows
Mobile OS)
Google Phone
• Google phone
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2.
The G1, 2008
Nexus One, 2010
• Android OS
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2008
Linux based
Open source
Compare to Apple iOS
The HTC G1 is the first
phone to feature the Google
Android OS.
Further reading: http://electronics.howstuffworks.com/google-phone1.htm
The Nexus One is
the first phone to
be sold by Google
directly to
consumers.
Current State:
Touch, Feel, Locate, Hear, See, Connect
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Top 5 Emerging Phone Technologies
1. WiFi Phones
Use WiFi to place calls by phone
(VoIP)
2: Mobile Augmented Reality
Add location-based information to
your surroundings
http://electronics.howstuffworks.com/emerging-phone-technologies1.htm
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Top 5 Emerging Phone Technologies
3: Open Source Cell Phones
phone software which can be used
on almost any cell phone
4: Mobile Payment
transfer or pay money instantly from
any bank account or credit line
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Top 5 Emerging Phone Technologies
5: Tactile Feedback
touch screen which feels and reacts
when you type on it
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Environmental Impact
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Energy efficiency
Elimination of toxins
Recyclability
Green Apps
Radiation emissions
– http://www.ewg.org/cellphone-radiation
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Coming Next
• Energy efficiency techniques in mobile phones
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