The Third Generation Personal Communication Systems: Research

1
The Third Generation Personal Communication
SystemsResearch Development

• Hong Nie
• Hongn_at_ece.ubc.ca
• Electrical Computer Engineering
• University of British Columbia

2
Order of Presentation

• First and second generation of personal
  communication systems
• Requirements for third generation systems
• Technical aims of IMT-2000
• Basic concepts of CDMA
• Performance enhancement features in IMT-2000
• Radio transmission technology proposals for
  IMT-2000
• Comparison of W-CDMA and CDMA2000
• Time schedules for IMT-2000

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Personal Communication Systems (PCS)

• PCS aim to provide users wireless access to
  existing communication networks instantly at any
  time, anyplace.
• 1G Systems TACS, AMPS, NTT
• 2G Systems GSM, IS-136, IS-95, PDC, PHC
• Serious limitations of 1G and 2G Systems
• - Low transmission rate, e.g., 9.6 kbps for GSM
• - Unable to support mobile multimedia
  applications.

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Requirements for 3G Systems

• More Advanced Services
• - Computer data with Internet access e-mail,
  real-time image transfer, multimedia document
  transfer, mobile computing
• - Telecommunications with mobility
  videoconferencing, video telephony
• - Audio/video content video on demand,
  interactive video service, electronic newspaper,
  teleshopping
• Better Quality of Service
• - Larger data transmission throughput and lower
  delay
• - Global roaming
• - Voice quality comparable to wireline systems

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Requirements for 3G Systems (Continue)

• Flexibility
• - Multiple environments
• - Bandwidth on demand
• - Modulation and multiple access selection
• - Inter and intra system hand over
• Ability to Migrate and Evolve
• - Coexistence with 2G systems
• - Evolution from 2G to 3G

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Technical Aims of International Mobile
Telecommunications 2000 (IMT-2000)

• Support of a wide range of transmission rate
• Up to 144 kbps for vehicular, 384 kbps for
  pedestrian in outdoor, and 2 Mbps in indoor and
  picocell environments.
• Support of both circuit-switched and
  package-oriented services.
• Support of both symmetric and asymmetric traffic.
• Support of soft hand over

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Multiple Access SchemesFrequency Division
Multiple Access (FDMA),Time Division Multiple
Access (TDMA), Code Division Multiple Access
(CDMA)
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Principle of CDMA
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Advantages of CDMA

• Higher spectral efficiency
• At least four times over digital TDMA or FDMA,
  and twenty time over analog FM/FDMA
• Protection against mulitpath interference
• Support of variable transmission rate
• Interference rejection
• Privacy

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Performance Enhancement Featuresin IMT-2000

• Smart Antenna
• - Multiple antennas allow the formation of beams
  towards the desired signal and nulls towards
  interferers, hence enhance signal quality and
  reduce interference.
• - The pilot symbols inserted both on the
  downlink and uplink make the use of adaptive
  antennas more feasible.

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Performance Enhancement Featuresin IMT-2000
(Continue)

• Multi-User Detection
• - Single use detection schemes treat
  interference as noise hence degrade performance
  as the number of interferers increases.
• - Multi-user detection detects both the desired
  signals and interference, hence improves the
  performance of recevier.

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Performance Enhancement Featuresin IMT-2000
(Continue)

• Transmit Diversity
• - In order to meet IMT-2000s stringent
  detection requirements in all environments,
  antenna diversity is indispensable.
• - Receiver diversity at mobile stations may not
  be feasible.
• - Using transmit diversity at base station can
  improve mobile station receiver performance.

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Performance Enhancement Featuresin IMT-2000
(Continue)

• Software Defined Radio
• - Conventional radio receiver is dedicated to an
  individual radio standard and optimized for that
  particular standard.
• - Software defined radio receiver digitizes
  signals with wideband analog-to-digital converter
  and implements most receiver functionalities with
  software re-configurable or parameterizable
  digital device.
• - The inherent flexibility of software defined
  radio can well satisfy the demanding requirements
  of IMT-2000 to provide multi-standards and
  multimedia services.

14
Radio Transmission Technology Proposals for
IMT-2000I. W-CDMA

• Proposed by Third Generation Partnership Project
  (3GPP)
• Europe European Telecommunications Standards
  Institute (ETSI)
• Japan Association of Radio Industries Businesses
  (ARIB) and Telecommunication Technology Committee
  (TTC)
• USA T1P1
• Korea Telecommunications Technology Association
  (TTA)

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Radio Transmission Technology Proposals for
IMT-2000II. CDMA2000

• Proposed by Third Generation Partnership Project
  II (3GPP2)
• USA Telecommunications Industry Association
  (TIA)
• Korea Telecommunications Technology Association
  (TTA)
• Strongly endorsed by Qualcomm and Ericsson

16
Radio Transmission Technology Proposals for
IMT-2000III. TD-SCDMA IV. W-TDMA

• Time Division Synchronous CDMA is proposed by
  Chinese Academy of Telecommunications Technology
• Wideband TDMA (EDGE) is proposed by
  Telecommunications Industry Association (TIA)

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Similarities between W-CDMA and CDMA2000

• Coherent forward and reverse link
• Fast power control both on forward link and
  reverse link
• Variable length orthogonal Walsh sequences for
  forward link channelization
• Complex QPSK spreading on both forward and
  reverse link
• Convolutional codes used as baseline (identical
  polynomials)
• Parallel Turbo code for higher data rates

18
Similarities between W-CDMA and CDMA2000
(Continue)

• Variable spreading factor to achieve higher data
  rate
• Orthogonal Walsh sequences to separate the
  parallel channels of users on the reverse link
• Non orthogonal reverse link based on PN
  scrambling codes
• Mobile assisted inter-frequency hard handoff
  procedures and intra-frequency soft handoff
  procedures
• Variable rate operation with blind rate
  estimation for simple services (e.g. voice)
• Continuous reverse link operation

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Major Differences between CDMA2000 and W-CDMA
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Major Differences between CDMA2000 and W-CDMA
(Continue)
21
Time Schedules for IMT-2000

• Radio transmission technology proposals
• - June 30, 1998
• Proposal Evaluations
• - Fall 1998
• Consensus building and final selection
• - March 1999 (The agreement in Fortaleza,
  Brazil)
• Detailed finalized technical specifications
• - January 2000
• Commercial Deployment
• - Year 2001-2004
• - May 2001, NTT DoCoMo