RAN 3g.pdf

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    Dimensioning, configuration and

    deployment of Radio Access

    Networks.

    part 5: HSPA and LTE

    HSDPA

    Enhanced Support for Downlink Packet Data

    Higher Capacity

    Higher Peak data rates

    Lower round trip delay time

    Part of release 5

    Similar to cdma2000 EV DO

    Shared Channel Transmission

    Higher order Modulation

    Fast Link adaptation

    Fast hybrid ARQ

    (MIMO to be considered for later releases)

    Shared Channel Transmission

    Efficient code and power utilization by dynamically sharing radio resources among multiple users

    Time domain (TTI = 2 ms)

    Code domain (up to 15 codes)

    Not all UEs are capable to receive data in consecutive TTI (Minimum inter-TTI time > 1)

    CC are not orthogonal due to multipath propagation self interference generated in the cell affecting capacity

    Channelization codes allocated

    for HS-DSCH transmission

    8 codes (example)SF=16

    SF=8

    SF=4

    SF=2

    SF=1

    User #1 User #2 User #3 User #4

    TTI

    Sharedchannelization

    codes

    time

    HSDPA - Shared channel transmission

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    Channel coding and throughput

    Channel coding at rates 1/4-3/4 Dynamically changed

    Higher order Modulation

    Allows for higher peak data rates QPSK 480kbps channel bit rate per code

    16QAM 960kbps channel bit rate per code Requires higher SNIR

    Smaller cells

    Shared channel transmission

    Radio channel conditions changes fast due to:

    Interference variations

    Path loss and shadowing

    Multipath fading

    HS-DSCH channel rate control = constant power

    Adaptive channel coding Adaptive modulation (QPSK 16QAM)

    Fast adaptation - TTI=2 ms

    Available rate is adjusted by selecting a Transport Format and Resource Combination (TFRC)

    The achievable rate dependent on:

    Available HS power

    Radio conditions

    UE category

    Available # HS codes 16QAM availability

    Load

    Fast link adaptation Modulation, coding and data rate

    Modulat ion Coding rateThroughput5

    CC

    Throughput

    10 CC

    Throughput

    15 CC

    QPSK

    1/4 600 kbps 1.2 Mbps 1.8 Mbps

    2/4 1.2 Mbps 2.4 Mbps 3.6 Mbps

    3/4 1.8 Mbps 3.6 Mbps 5.4 Mbps

    16QAM

    2/4 2.4 Mbps 4.8 Mbps 7.2 Mbps

    3/4 3.6 Mbps 7.2 Mbps 10.8 Mbps

    4/4 4.8 Mbps 9.6 Mbps 14.4 Mbps

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    SINR vs throughput

    Throughput is afunction of modulation,

    coding and SNIR

    RNC

    Air interface limitations HW limitations

    Channel elements

    in NodeB

    Transmission(x E1)

    - DL power

    - DL codes

    - UL interference

    Capacity management overview 3G RAN

    384 kbps384 kbps384 kbps

    1Mbps

    0.5Mbps

    Power control

    Constant bit rate

    RNC

    R99

    Power controlled

    Power control and rate control

    Rate control

    Constant DL power

    RNC

    R5

    Rate controlled5Mbps3Mbps

    384 kbps

    Deployment strategy example

    f1: R99

    Hot spots

    Dense urban

    Urban

    Suburban

    Rural

    Deployment

    phase

    f2: R99 + HS

    f1: R99 + HS

    f2: R99 + HS

    f1: R99 + HS

    f1: R99 + HS

    f2: R99 + HS

    f1: R99

    f1: R99 + HS

    Initial phase

    Mature phase

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    LTE 4G Mobile Broadband

    A SHORT SUMMARY ON BEHALF OF ERICSSON

    HSPA and LTE = Mobile Broadband

    HSPA High-Speed Packet Access (Turbo-3G)

    Gradually improved performance in existing 3G networks

    LTE Long-Term Evolution (4G) Significantly higher performance and user experience

    in a wide range of spectrum allocations

    Packet-switched services only

    Fulfills IMT-Advanced requirements

    Studies Specs

    LTE LTE-Advanced

    HSPA HSPA evolutionHSDPA

    2004 2006 20082002

    Requirements

    WCDMA

    2005 2007

    Stefan Parkvall

    LTE 4G Mobile Broadband

    via trials

    to commercial operation!

    http://www.teliasonera.com/4g/index.htm

    LTE Testbed

    2007

    http://www.ericsson.com/thecompany/press/releases/2009/12/1360881

    Testbed 2007, 20 MHz, 2x2 MIMO

    12

    23

    37

    54

    74

    97

    123

    154

    700 m

    From early studies

    Rel-9 Rel-10Rel-8

    Basic LTE functionality Enhancements & extensions Further extensions

    IMT-Advanced compliant

    FDD and TDD supportBandwidth flexibility

    ICICMulti-antenna supportdata1

    data2

    data3

    data4

    C ha nn el -d ep en de nt sch ed ul in g H yb ri d ARQ

    OFDM t ransmission

    MBMS Carrier Aggregation

    Relaying

    Multi-antenna extensionsDual-layer beamforming

    Positioning

    LTE Basic Radio-Access Principles

    2008 2009 2010

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    Transmission Scheme

    Downlink OFDM Parallel transmission on large number of

    narrowband subcarriers

    Uplink DFTS-OFDM DFT-precoded OFDM

    Benefits:

    Avoid own-cell interference

    Robust to time dispersion

    Main drawback

    Power-amplifier efficiency

    Tx signal has single-carrier properties

    Improved power-amplifier efficiency

    Improved battery life

    Reduced PA cost

    Critical for uplink

    Equalizer needed Rx Complexity

    Not critical for uplink

    Cyclic-prefix

    insertion

    OFDM modulatorDFT precoder

    DFT IFFTIFFTCyclic-prefix

    insertion

    Multi-antenna Transmission

    Diversity for improvedsystem peformance (robustness)

    Beam-forming for improved coverage(less cells to cover a given area)

    SDMA for improved capacity(more users per cell)

    Multi-layer transmisson (MIMO)for higher data rates in a given bandwidth

    The multi-antenna technique to use depends on what to achieve

    Spectrum Flexibility

    Operation in differently-sized spectrum allocations

    Core specifications support any bandwidth from 1.4 to 20 MHz

    Radio requirements defined for a limited set of spectrum allocations

    6 RB (1.4 MHz)

    100 RB (20 MHz)

    Support for paired andunpaired spectrum allocations

    time

    FDDtime

    Half-duplex FDD(terminal-side only)

    timeTDD

    10 MHz 15 MHz 20 MHz3 MHz 5 MHz1.4 MHz

    with a single radio-access technology economy-of-scale

    Supported Frequency Bands

    20251710

    19801785 18801805

    2110 2200

    2110 2170

    26902500

    2500 2570 2620 26901710

    2300 2400

    General

    bands

    Regional

    bands

    Local

    bands

    Band 3 Band 1 Band 7

    Band 2

    Band 4

    Band 10

    Paired Uplink Paired Downlink

    Legend:

    Unpaired

    19101850 19901930

    15251427

    IMT IMT IMTITU: IMTMobile

    B an d 11 & 21 (J ap an ) B an d 9 (J ap an )

    Band 39 (China)

    Band 36Band 35

    (Band 37)

    19101850 19901930

    Band 33Band 34

    Band 40

    Band 38

    Band 41

    2496 2690

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    Supported Frequency Bands

    Paired Uplink Paired Downlink

    Legend:

    960698

    IMT

    General

    bands

    Local bands

    824 849 869 894

    830 845 885875

    880 915 925 960

    Band 8

    Band 5Band 12Band 13

    Band 14

    Band 18 &19 (Japan)

    ITU:

    Band 17

    815 860

    791 821 832 862

    Band 20

    Regional

    bands

    Rel-9 Rel-10Rel-8

    Basic LTE functionality Enhancements & extensions Further extensions

    IMT-Advanced compliant

    FDD and TDD supportBandwidth flexibility

    ICICMulti-antenna supportdata1

    data2

    data3

    data4

    C ha nn el -d ep en de nt sch ed ul in g H yb ri d ARQ

    OFDM t ransmission

    MBMS Carrier Aggregation

    Relaying

    Multi-antenna extensionsDual-layer beamforming

    Positioning

    LTE Continuous Evolution

    2008 2009 2010

    RelayingRel-10

    Repeater

    Possible already in Rel-8, simply amplifies and retransmits recevied signal

    Relaying (added in Rel-10)

    Relay = small base station connected to RAN using LTE radio resources

    Mainly interesting if fibre/microwave backhaul is more expensive than using LTE

    spectrum

    Relay cell

    Donor cell

    HetNets

    What?

    Low power nodes placed throughout a macro-cell layout

    Heterogeneous Networks

    Conventional

    Independent pico cells

    Relay

    Independent relay cells

    Relay connected to macro

    RRU

    Remote pico antenna,

    processing in macro

    No new pico cells

    Why?High data rates dense infrastructure...but non-uniform user

    distribution

    Macro for coverage, pico for high data ratesHow?

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    The Wireless Evolution

    Additional functionality and

    capabilities

    Improved performance

    New application areas

    Everything is connected 50 billion devices

    Need for new business models?

    More Reading

    Available in English, Chinese, Korean and Japanese.

    ...or read The Book!

    Open the 3GPP specifications...