Generations of wireless networks

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Generations of wireless networks

• Chapter 1

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1G wireless standards
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2G wireless
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3G wireless
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4G wireless
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Where is wireless access going???

• Many (maybe too many) wireless technology choices
  are available today
• Short-range (WLANs, sensor technologies such as
  Bluetooth or Ultra Wideband)
• Long-range (Cellular)
• Broadband (WiMAX/WiBRO, Flash-OFDM, etc.)
• Broadcast (DVB-H, DMB, MediaFLO)
• Device segmentation is not universal
• Can vendors address the needs of the subcontinent
  while still making a global product?
• Democratization of wireless technologies
• Sales channels in the subcontinent are so varied
  do device features have to stop with the
  original manufacturer?

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Air Interface Technologies
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So Many Technology Choices
6.
3.9G
5.
3GHSDPA
3GHSUPA
4.
WiBRO
WiMAX (fixed)
WiMAX (mobile)
3.
WLAN Hotspots
2.
Flash-OFDM
802.20
1.
3GPP2 systems (1X, EV-DO, nxDO, Phase II
Evolution)
2009
2005
2006
2007
2008
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• Cellular technologies
• Mature GSM/EDGE, CDMA
• Voice-only products approaching commodity status
• Ongoing rollout 3G (WCDMA) and 1X-EV-DO (CDMA
  evolution)
• What are the usage scenarios in the subcontinent?
• Bringing the internet to underserved user
  segments?
• Fancy services for a very small, very rich niche?
• Future 3.9 G
• Extending the high throughput capabilities of
  WLAN technologies into cellular
• Short range technologies (WLAN primarily)
• Not much good without an internet backbone goes
  hand-in-hand with broadband penetration

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• Wireless broadband
• Slowly gaining traction in the West telecom
  operators are cautious because of previous
  overinvestment in other broadband technologies
  (DSL, optical)
• Very clear usage scenario in the subcontinent
• Strong backbone solution can bring internet
  access to remote areas and villages
• Is there enough business to get a major telecom
  vendor excited?
• Broadcast for wireless (DVB-H, DMB, MediaFLO)
• Certainly a proven appetite in Asia for TV
• Hard to say if users in the subcontinent will
  watch TV on small devices

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Future Wireless System Development

• Increasing penetration
• Lowering costs of devices
• Improving return for operators
• Customizing services for the local population
• There is a quandary with going forward with a
  regional technology
• Will global vendors support it?
• If not, is there a local vendor base?
• Is the scale of the technology large enough to
  drive down cost?

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• Low penetration provides some opportunity
• Legacy of cellular circuit-switched services
  (particularly voice) not insurmountable
• Rather than develop a new technology for South
  Asia, subcontinent researchers should try to
  drive locally enabling technologies through
  standardization, for example
• Improve cellular technologies for VoIP, enabling
  lower cost backbone
• Advanced cellular receiver design to improve
  voice capacity
• Driving targeted features in global
  standardization would be a win-win scenario for
  South Asia and the global vendor community
• Global technologies mean large scale costs can
  go down
• Opportunity for Asian researchers to influence
  standards that are deployed over the world
• Cellular is the best choice

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Devices
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Wireless Access Mapping

• Voice-only
• 2G (GSM, cdma2000 1X)
• Messaging and limited data services
• 2G (GSM, cdma2000 1X)
• Advanced wireless
• 2G (GSM, cdma2000 1X)
• 3G (WCDMA, cdma2000 1X-EV-DO)
• High-end business/multimedia
• 3G (WCDMA, cdma2000 1X-EV-DO)
• Complimentary access (WLAN a definite, maybe
  WiMAX)

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Democratization of Wireless Technologies

• Example Research conducted in Delhi by Nokia
  Research Centers Usability Group, Tokyo

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Karol Bagh market area of Delhi, India 200
small indoor shops, and 100 outdoor market stalls
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this one building, approx. 60 small shops spread
over 4 stories
wholesaling phone accessories and repair equipment
small workshops actively repairing phones, and
offering training
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minimal street customer care center flat
surface screwdriver new component knowledge
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What can we take away?

• Huge after market service industry has developed
  in South Asia
• Phone repair, re-sale
• Reconditioned phone sales may be the ticket to
  providing new cellular service to customer
  segments, e.g.
• Basic voice to BOP
• Advanced multimedia to existing voice-only users
• Large proliferation of after-market services may
  also be able to provide some limited enhancement
  to cellular devices
• If multinational vendors can tap into this more
  effectively rather than view it as a threat, then
  consumer insight could result
• Are there low-cost innovations that could better
  serve an emerging market?

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Wide Area Wireless Technology

• What are the next few years going to bring?

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• From the Seventies through the Nineties, most
  cellular systems were developed through consensus
  and standardization
• AMPS was a technology delayed nearly 20 years due
  to building consensus!
• GSM has proven to be long-lasting and
  widely-supported also developed through
  industry cooperation
• In the Nineties, proprietary technologies emerged
• IS-95 (CDMA), proposed by Qualcomm Inc.
• Followed by 1X-EV-DO in the late Nineties
• Nowadays, several more proprietary alternatives
  to standardized cellular technologies have gained
  notoriety (not necessarily widespread adoption)
• Flarions Flash OFDM
• Other technologies may be nearly proprietary,
  with a small number of companies driving
  development

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• What makes proprietary technologies attractive?
• Good ideas are sometimes compromised in the
  standardization process
• Standardization process can delay product
  development
• Proprietary route has pitfalls
• Lack of widespread vendor support for a given
  technology
• Intellectual property concentrated in the hands
  of a few players
• Is there a middle ground?
• Yes, when a small group of companies who can
  support a given technology develop it together
  outside of standards
• Standardization can follow, to allow other
  equipment manufacturers exposure to the
  technology and ensure interoperability

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Where does spectrum come into the picture?

• Spectrum is not as cheap as once thought
• North American example recent consolidation
  among operators has left winners and losers in
  spectrum
• New 3G spectrum auctions (1.7/2.1 GHz) have not
  happened fast enough to address this
• Operators want to evolve existing cellular
  technologies in a manner that continues to
  leverage their huge investment in 3G equipment
• Backwards-compatibility will be a driver
• Makes it difficult to find a disruption point for
  good proprietary technologies
• The overlap period becomes a driver how long
  does the network operator have to support legacy
  subscribers while the new technology is being
  introduced?

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• These are issues that will influence the
  evolution of cellular technologies
• New cellular systems will leverage as much as
  they can from legacy systems
• For example, reuse of control/overhead mechanisms
  from legacy
• Baggage from the legacy systems can reduce the
  benefits from innovation in evolution systems
• In response, wireless vendors need to get more
  creative as to what defines backwards
  compatibility
• Need to be selective in what is actually
  leveraged from the legacy system
• Also, need to consider how much evolution in the
  air interface technology is necessary for
  improving system performance
• Can improved performance be addressed through
  software/middleware innovation?

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• Wireless broadband (802.16)
• Slowly gaining traction in the West telecom
  operators are cautious because of previous
  overinvestment in other broadband technologies
  (DSL, optical) Technology positioning is a
  problem for cellular operators already deploying
  3G
• The target customer base overlaps
• Broadcast for wireless (DVB-H, DMB, MediaFLO)
• Certainly a proven appetite in Asia for TV bodes
  well for DMB in East Asia
• European and North American markets unproven yet
  for handheld digital TV

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What about Voice Services?

• Voice is still the killer app for cellular
• Without a compelling data application for 3G, it
  may be a safe starting point to say that VoIP
  will be the killer app for 3G evolution
• This profoundly affects cellular evolution
• Air interface must be optimized for low rate, low
  delay service such as voice
• This could come in conflict with design goal of
  extending high speed capabilities seen in WLAN to
  cellular
• As long as voice is perceived as a separate
  revenue stream rather than just another IP-based
  service, this could hamper cellular evolution
• In other words, should future cellular systems
  performance be benchmarked primarily by voice
  spectral efficiency?

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Quality-of-Service for Internet
ApplicationsShould cellular provide the same as
broadband?

• Many internet applications are not designed with
  a cellular link in mind
• Underlying expectation of relatively constant
  quality of service (QoS)
• Throughput is assumed to be known during session
  setup
• Certainly totally different applications can be
  designed for cellular, but some innovation in the
  middleware area may improve application
  performance over cellular without
• Redesigning air interface
• Rewriting application
• Example online multiplayer gaming (First
  person shooter)
• Player actions based on other player actions
• Near real time