Introduction to 3G network

• + - History
  • + - 1G
    • NMT (Nordic Mobile Telephone)
      • NMT-450
      • NMT-900
        • International Roaming is possible
      • Scandinavia, Ecntral and Southern Europe
    • TACS (Total Access Communications System)
      • UK standard, based on AMPS
      • 900 MHz
    • AMPS (Advanced Mobile Phone Service)
      • US standard
      • 800 MHz
    • MCS
      • NTT: first cellular network in Japan
  • + - 2G
    • Feature
      • use digital radio transmission for traffic
      • basic GSM uses 900 MHz
      • 1800 MHz
    • GSM (Global System for Mobile communications)
      • Most successful and widely used 2G system
      • TDMA
    • D-AMPS (digital AMPS)
      • US-TDMA, IS-136, or just TDMA
    • CDMA IS-95 (Code-division Multiple Access)
      • Developed by Qualcomm
      • the only 2G CDMA standard so far
      • IS-95 also called cdmaOne (brand name)
    • PDC (Personal Digital Cellular)
      • Frequency bands
        • 800 MHz
        • 1500 MHz
      • Feature
        • physical layer: similar to D-AMPS
        • protocal stack: resembles GSM
      • Only operated in Japan
    • Digital Cordless systems
      • CT2
      • DECT (Digital Enhanced Cordless Telecommunications)
      • PHS (Personal Handyphone System)
  • 2.5G
    • new technologies
      • HSCSD High-speed Circuit-switched Data)
        • allocate 4 time slots for transmisstion (9.6 Kbps or 14.4 x 4)
        • + - summary
          • Good: software updates to network, and phone; good for real time apps
          • Bad: usage of scarce radio resources
      • GPRS (General Packet Radio Services)
        • up to 115 Kbps
        • packet switched
        • suitable for non real-time apps
        • bursty data is well handled
        • do not guarantee an absolute maximum delay
      • EDGE (Enhanced Data Rates for Global Evolution)
        • 3 folds of original GSM speed
        • 8PSK (eight-phase shift keying)
        • + GPRS --> EGPRS
          • 384 Kbps maximum
    • IS-136 + (GPRS || EDGE) --> 2.5G
    • Qualcomm
      • CDMA2000 1xRTT
        • IS-95: 14.4 Kbps, 1xRTT: 64 Kbps
        • IS-95 + IS-95B or upgrade CDMA2000 1xRTT -->2.5G
      • HDR (High Data Rate)
        • 2.4 Mbps
        • standardized in IS-856
        • 1xEV-DO (1x Evolved Data Optimized)
          • Add a TDMA component beneath code component
    • PDC-P (NTT DoCoMo)
      • i-mode
• 3G standard proposals
  • UMTS (Universal Mobile Telecommunications System)
    • Done by ETSI SMG (Special Mobile Group)
    • UMTS Forum was created in 1996
  • new technologies
    • + - WCDMA
      • the bandwidth is 5 MHz or more (144kbps, 384kbps or even 2Mbps
      • network
        • Synchronous
          • CDMA2000
            • compatible with IS-95
            • manufacturer: Qualcomm, Lucent, Motorola
            • use ANSI-41 core network
            • 3GPP2 (less support than 3GPP)
          • good/not good
            • good: effecient radio interface
            • bad: expensive H/W
        • Asynchronous
          • ETSI/ARIB WCDMA
            • most popular 3G system
            • manufacturer: Ericsson, Nokia, NTT DocoMo
            • rename to UTRAN (FDD)
            • based on GSM MAP network
            • 3GPP
      • feature
        • fast power control
        • vary bit rate, service params on frame by frame basis
    • Advanced TDMA
      • UWC-136 only
    • Hybrid CDMA/TDMA
      • Not supported
      • in fact, it likes UTRAN TDD
    • OFDM
      • spectrum: effecient
      • user: DAB, DVB, 802.11a, 802.11g, ADSL
      • TDMA/CDMA possible
      • good
        • bandwidth effecient
        • resistance to
          • narrow band interference
          • multipath interefrence
  • IMT-2000
    • umbrella spec of all 3G systems (origin from ITU)
    • IMT Direct Spread (IMT-DS)
      • UTRA FDD
      • 3GPP
    • IMT Multicarrier (IMT-MC)
      • CDMA2000
      • 3GPP2
    • IMT Time Code (IMT-TC)
      • UTRA-TDD/TD-SCDMA narrowband TDD
      • 3GPP
    • IMT Single Carrier (IMT-SC)
      • UWC-136
    • IMT Frequency Time (IMT-FT)
      • DECT
• + - 3GPP
  • an org that develops spec for 3g system based on UTRA radio interface
  • partners
    • ETSI
    • ARIB
    • TTA
    • TTC
    • CWTS(china wireless telecommunications Standard
  • ULTRA
    • FDD
      • + - vocabs
        • chip: a bit in a code word
        • spreading factor: chip rate / data bit rate
        • spreading code: a sequence of chips used to modulate the data bits
      • up/down use separate freq bands
      • chip rate: 3.84 Mcps
    • TDD
      • NOrmal: 3.84 Mcps
      • TD-SCDMA: 1.28 Mcps
    • channels
      • physical (air interface)
      • transport
        • between layer 1 and 2
        • define how data is sent over the air
      • logical
        • within layer 2
        • define the type of data to be sent
• 3GPP2
  • should be backward compatible with IS-95