Top Banner
HUAWEI TECHNOLOGIES CO., LTD. All rights reserved www.huawei.com Internal OWJ100101 WCDMA Radio Network Coverage Planning ISSUE1.0
72

147181030 003 WCDMA Radio Network Coverage Planning ISSUE 1

Nov 22, 2015

Download

Documents

olumiderare

WCDMA Radio Network
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
  • HUAWEI TECHNOLOGIES CO., LTD. All rights reserved

    www.huawei.com

    Internal

    OWJ100101 WCDMA Radio Network Coverage

    PlanningISSUE1.0

  • HUAWEI TECHNOLOGIES CO., LTD. Page 2All rights reserved

    Upon completion of this course, you will be able to:Know the contents and process of network planning.Understand the uplink budget and its elements.Understand the downlink budget and its elements.Familiarize the coverage enhancement technologies.

  • HUAWEI TECHNOLOGIES CO., LTD. Page 3All rights reserved

    Section 1 Process of WCDMA Network Planning Section 1 Process of WCDMA Network Planning

    Section 2 Uplink BudgetSection 2 Uplink Budget

    Section 3 Downlink Budget Section 3 Downlink Budget

    Section 4 Coverage Enhancement TechnologiesSection 4 Coverage Enhancement Technologies

  • HUAWEI TECHNOLOGIES CO., LTD. Page 4All rights reserved

    Section 1 Process of WCDMA Network PlanningSection 1 Process of WCDMA Network Planning

    1.1 Overview of Radio Network Planning1.1 Overview of Radio Network Planning

    1.2 Huawei Concept of Radio Network Planning 1.2 Huawei Concept of Radio Network Planning

    1.3 Process of Radio Network Planning 1.3 Process of Radio Network Planning

  • HUAWEI TECHNOLOGIES CO., LTD. Page 5All rights reserved

    Definition and Category of Network Planning

    Focus of the train: Planning of radio network.

    Definition: Network planning means that proper network elements (NEs) are

    selected according to the network target, network evolution requirement, and cost, and then the quality, configuration, and connection mode of the NEs are determined to facilitate engineering implementation.

    Categories: Planning of core network Planning of radio network Planning of transmission network

  • HUAWEI TECHNOLOGIES CO., LTD. Page 6All rights reserved

    Importance of Radio Network Planning in 3G

    Importance: The construction cost of the mobile

    communications network mainly lies in the equipment investment.

    Among the three parts of the 3G network (radio access network, transmission network, and core network), the radio access network occupies more than 70% investment.

    The investment in the radio access network depends on the number and configuration of the BSs.

  • HUAWEI TECHNOLOGIES CO., LTD. Page 7All rights reserved

    Compare WCDMA Network Planning with that of GSM

    In the GSM system, the structure and frequency of the cellular network are planned in order to ensure that the co-frequency and adjacent-frequency interference meet the call quality requirement.

    If the interference requirement is met, the number of supported subscribers can be calculated based on the number of carrier frequencies and the number of timeslots.

    The coverage of the GSM system depends on the transmit power of the transmitter and the demodulation performance of the receiver.

    The GSM mainly offers voice service, and the GoS and design objective are relatively simple.

    f1

    f1

    f2

    f2

    f3

    f1

    f1

    f2

    f2

    f3

    f3f1

    f2f1

    f3f1

    WCDMA uses the spread spectrum technology, so it can realize 11 frequency multiplexing without frequency planning.

    The capacity of each carrier in WCDMA is "soft" because it is related to factors such as environment and adjacent-cell interference.

    The coverage of the WCDMA system is related to the system load. If the system load increases, the coverage will shrink.

    The WCDMA system supports services with different rate and QoS, including voice service, and their coverage capacity is different. In the network planning, the system performance shall be optimized through reasonable planning and radio resource management.

    f1

    f1

    f1

    f1

    f1

    f1

    f1

    f1

    f1

    f1

    f1f1

    f1f1

    f1f1

  • HUAWEI TECHNOLOGIES CO., LTD. Page 8All rights reserved

    Section 1 Process of WCDMA Network PlanningSection 1 Process of WCDMA Network Planning

    1.1 Overview of Radio Network Planning 1.1 Overview of Radio Network Planning

    1.2 Huawei Concept of Radio Network Planning1.2 Huawei Concept of Radio Network Planning

    1.3 Process of Radio Network Planning 1.3 Process of Radio Network Planning

  • HUAWEI TECHNOLOGIES CO., LTD. Page 9All rights reserved

    Huawei Concept of Wireless Network Planning Optimal coverage for profitable services

    The 3G network is a multi-service network, so the network resources need be distributed among different services. The cell radius and coverage scheme should be determined after the profitable services and their coverage quality are determined. At the early stage of the 3G network, if the planning focuses on high-speed data service, it will result in waste of the BSs because there are not enough services.

    Competitive core service Core service refers to the service that have a long-term effect on the network

    development. It is possible that the core service is not profitable in a short period, but is the attraction of the subscriber increase and service development, for example, high-speed data service. Therefore, the quality of the core service should be guaranteed in order to show the service and performance advantages of the 3G network and promote the operator's brand.

  • HUAWEI TECHNOLOGIES CO., LTD. Page 10All rights reserved

    Huawei Concept of Wireless Network Planning

    Highest capacity based on limited resources

    The capacity of the 3G network is mainly affected by interference. Reasonable parameter planning may help to reduce intra-cell and inter-cell interference, improve the cell capacity, and make full use of the limited resources.

  • HUAWEI TECHNOLOGIES CO., LTD. Page 11All rights reserved

    Huawei Concept of Wireless Network Planning

    Lowest overall cost of network construction

    The construction of the radio network goes through the lifecycle of the network. In the planning, further development shall be considered, in order to reduce the total cost of network construction.

  • HUAWEI TECHNOLOGIES CO., LTD. Page 12All rights reserved

    Section 1 Process of WCDMA Network PlanningSection 1 Process of WCDMA Network Planning

    1.1 Overview of Radio Network Planning 1.1 Overview of Radio Network Planning

    1.2 Huawei Concept of Radio Network Planning 1.2 Huawei Concept of Radio Network Planning

    1.3 Process of Radio Network Planning1.3 Process of Radio Network Planning

  • HUAWEI TECHNOLOGIES CO., LTD. Page 13All rights reserved

    Process of Wireless Network Planning

    Radio Network Dimensioning (RND) At the early stage of the project planning, the future

    network is preliminarily planned, and the configuration and the number of RAN NEs are output for preliminary project negotiation and for cost estimation in contract signing.

    Pre-planning of radio network

    At the mid stage of project planning, based on the dimensioning output, the future network is planned in detail, and the accurate network scale and theoretical site location are determined. A pre-planning report will be output for mid-stage project and cost estimation in contract signing.

  • HUAWEI TECHNOLOGIES CO., LTD. Page 14All rights reserved

    Process of Wireless Network Planning

    Cell planning of radio network

    At the later stage of project planning, based on the pre-planning output, each selected site is surveyed, and the related cell parameters are determined. If the result is quite different from the planning, the cell parameters and planning effect should be checked through simulation, and the output report would be the final radio network planning scheme that can guide the project implementation.

  • HUAWEI TECHNOLOGIES CO., LTD. Page 15All rights reserved

    Process of Radio Network Planning

  • HUAWEI TECHNOLOGIES CO., LTD. Page 16All rights reserved

    Radio Network Dimensioning

    Radio network dimensioning is a simplified analysis of the future network. Objective:

    To obtain the network scale (Approximate BS quantity and configuration), to obtain the construction period, and to obtain information such as electronical cost and human resource cost.

    Method:Select a proper propagation model, and subscriber mobility, distribution, and traffic models, and then estimate the site quantity, cell quantity, coverage size and capacity.

  • HUAWEI TECHNOLOGIES CO., LTD. Page 17All rights reserved

    Requirement of RND parameters Information of coverage area

    The engineers of RNP should know exact information about coverage area ,for example :

    Area , economy, population Distribution of cluster The information of mobile communication market

    Target of network The target of network should include several factors:

    Service Coverage area & Coverage quality Network Capacity Target load of cell

  • HUAWEI TECHNOLOGIES CO., LTD. Page 18All rights reserved

    Requirement of RND parameters

    Limited by network scale & Building plan in different phase

    Base on commercial contract

    Base on RND result if there is no commercial contract

    Information of available site

    For a new operator who doesnt have abundant 2G mobile communication network sites, the RNP engineer should collect exact information about available site.

  • HUAWEI TECHNOLOGIES CO., LTD. Page 19All rights reserved

    Radio Network dimensioning

    Coverage information Coverage area Coverage probability

    Capacity information Traffic model Service model Subscriber density

    Quality information QoS requirement GoS requirement Demodulation threshold

    System scale

    Site quantity

    System configuration

    Sector structure

    Carrier quantity

    Network construction cost

    Site cost

    Equipment cost

    InputInput OutputOutput

    Coverage dimensioning

    Capacity dimensioning

  • HUAWEI TECHNOLOGIES CO., LTD. Page 20All rights reserved

    Radio Network Pre-planning

    Based on radio network dimensioning, the network pre-planning intends to determine the initial layout and theoretical location of the BSs and select engineering parameters (BS location, network hierarchy, transmit power, antenna layout/type/direction/tilt angle, and so on) and some cell parameters (common channel, transmit power of traffic channel, orthogonal factor, cell scrambling code, and so on) .

  • HUAWEI TECHNOLOGIES CO., LTD. Page 21All rights reserved

    Radio Network Pre-planning Based on the result of RND,

    theoretical location of site, parameters of project, parameters of cell, We should carry out coverage simulation.

    We should carry out more detailed adjustment (for example amount of NodeB, configuration of NodeB, antenna altitude, antenna azimuth) after analyzing the results of coverage simulation.

    Finally ,we should get perfect coverage result.

  • HUAWEI TECHNOLOGIES CO., LTD. Page 22All rights reserved

    Radio Network Pre-planning Radio Network Pre-planning report

    We should output Radio Network Pre-planning report after finishing previous jobs. Radio Network Pre-planning report should include following factors:

    Introduce of project background Information of planning area :area, population, cluster Project of radio network pre-planning: site distribution map, site list

    ( include site name, latitude ,longitude, parameters) Performance of project :based on the simulation result Appendix: statistical diagram about performance

  • HUAWEI TECHNOLOGIES CO., LTD. Page 23All rights reserved

    Radio Network Cell Planning Flowchart of cell planning Flowchart of cell planning

    N

    Site survey report

    Site selection

    System emulation

    Design objective

    met?

    Wireless network planning report

    Noise test

    Noise test report

    Wireless network pre-planning

    report

    Site survey

    N

    NewSite

    2G

    Search

    Rings

    Yes

    Site list

    New site (prefix: NewSite)?

    2G site?

    Output Search Rings

    Obtain candidate sites

    Site conditions determined?

    Site survey report

    Site requirement

    met?

    Yes

    Site survey

    No

    Noise test Noise test report

    Wireless network pre-planning

    report Yes

    No

    No

    Yes

    Yes

    No

  • HUAWEI TECHNOLOGIES CO., LTD. Page 24All rights reserved

    Radio Network Cell Planning site survey In fact , perfect site position could not be acquired. We must select some backup

    site. But how can we select the backup site? Based on experience , backup site is selected in SEARCH RING scope ,

    SEARCH RING =1/4*R, at the same time ,we still consider its height. We still pay attention to some other factors when we select the backup sites :

    Radio propagation Site position Site height Surrounding

    Job implementation Space of room Antenna installation Transmission Power

    Commercial factor Rent

  • HUAWEI TECHNOLOGIES CO., LTD. Page 25All rights reserved

    Radio Network Cell Planning System Simulation

    System Simulation class

    Static simulation Static simulation would gain the

    performance of radio network based on snapshot

    Dynamic simulation Dynamic simulation would gain the

    performance of radio network based on analysis of mobile subscribers.

    At present, Static simulation is in common use. Monte Carlo simulation is one type of static simulations

    The example of Monte Carlo simulation

  • HUAWEI TECHNOLOGIES CO., LTD. Page 26All rights reserved

    The example about Monte Carlo simulation

    100%100% 100%100%20%20% 60%60%

    0%0% 75%75% 40%40%60%60%

    Access ratioAccess ratio

  • HUAWEI TECHNOLOGIES CO., LTD. Page 27All rights reserved

    Distribution of NodeBs

  • HUAWEI TECHNOLOGIES CO., LTD. Page 28All rights reserved

    Simulation diagram pilot coverage intensity

  • HUAWEI TECHNOLOGIES CO., LTD. Page 29All rights reserved

    Simulation diagram pilot coverage quality (Ec/Io)

  • HUAWEI TECHNOLOGIES CO., LTD. Page 30All rights reserved

    Coverage probability of 12.2k voice service

  • HUAWEI TECHNOLOGIES CO., LTD. Page 31All rights reserved

    Coverage probability of 64k video phone service

  • HUAWEI TECHNOLOGIES CO., LTD. Page 32All rights reserved

    Coverage probability of 144k Net Meeting service

  • HUAWEI TECHNOLOGIES CO., LTD. Page 33All rights reserved

    Coverage probability of 384k HTTP service

  • HUAWEI TECHNOLOGIES CO., LTD. Page 34All rights reserved

    Simulation result about pilot pollution

  • HUAWEI TECHNOLOGIES CO., LTD. Page 35All rights reserved

    Summary of the Section

    Categories of radio network planning

    Huawei concept of radio network planning

    Differences between GSM network planning and WCDMA network planning

    Process of radio network planning

    Input and output requirements of the radio network pre-planning

    This Section covers the following: This Section covers the following:

  • HUAWEI TECHNOLOGIES CO., LTD. Page 36All rights reserved

    Section 1 Process of WCDMA Network PlanningSection 1 Process of WCDMA Network Planning

    Section 2 Uplink BudgetSection 2 Uplink Budget

    Section 3 Downlink Budget Section 3 Downlink Budget

    Section 4 Coverage Enhancement TechnologiesSection 4 Coverage Enhancement Technologies

  • HUAWEI TECHNOLOGIES CO., LTD. Page 37All rights reserved

    CapacityCoverageQuality Relation between capacity, coverage, and quality of the WCDMA

    system The WCDMA system is a self-interference system, and its

    capacity, coverage, and quality closely related to each other. Capacitycoverage (e.g. cell breath)

    If the load increases, the capacity and interference also interference, and the coverage shrinks.

    Capacityquality (e.g. outer loop power control) The system capacity may increase by lowering the quality of

    some connections. Coveragequality (e.g. AMRC)

    The coverage may increase by lowering the quality of some connections.

  • HUAWEI TECHNOLOGIES CO., LTD. Page 38All rights reserved

    Process of Coverage Budget Environment features of the

    planned area

    Site capacity

    Indoor coverage

    Coverage probability

    Propagation model

    Equipment performance

    Create link budgetCreate link budget

    Obtain cell radius Obtain cell radius

    Calculate site area Calculate site area

    Specify site quantity of the area

    Specify site quantity of the area

    Maximum path loss

    Minimum cell radius

    Maximum site coverage area

    Site quantity=planned area/site coverage areaSite quantity=planned area/site coverage area

  • HUAWEI TECHNOLOGIES CO., LTD. Page 39All rights reserved

    Fundamental Principle

    Link Budget: Link Budget intends to estimate the system coverage by analyzing the factors of the propagation of the forward signal and reverse signal, in order to obtain the maximum propagation loss after certain communications quality is ensured.

    TX

    CombinerDuplexer

    Feeder

    RX

    Pout_BS

    Lc_BSLf_BS

    Ga_BSNodeB

    TX

    RX

    Pout_UE

    Ga_UEUE

    CombinerDuplexer

    PL_DLPL

    _UL

    Body Loss

    FadingMargin

    PenetrationLoss

  • HUAWEI TECHNOLOGIES CO., LTD. Page 40All rights reserved

    Algorithm Introduction

    PL_UL=Pout_UE +Ga_BS+Ga_UE Lf_BS+Ga_SHO Mpc Mf MI Lp Lb S_BS

    PL_UL: Maximum propagation loss of the Uplink Pout_UE: Maximum transmit power of the traffic channel of the UE Lf_BS: Cable loss Ga_BS: Antenna gain of the BS; Ga_UE: Antenna gain of the MS Ga_SHO: Gain of soft handover Mpc: Margin for fast power control Mf: Slow fading margin (related to the propagation environment) MI: Interference margin (related to the designed system capacity) Lp: Penetration loss of a building (used if indoor coverage is required) Lb: Body loss S_BS: Sensitivity of BS receiver (related to factors such as service and

    multi-path condition)

    Uplink (reverse)Uplink (reverse)

  • HUAWEI TECHNOLOGIES CO., LTD. Page 41All rights reserved

    Elements of WCDMA Uplink BudgetMax Power of TCHBody LossGain of UE Tx AntennaEIRPGain of BS Rx AntennaCable LossNoise Figure (BS)Required Eb/No (BS)Sensitivity of BS Receiver UL Cell LoadInterference MarginBackground Noise Level

    SHO Gain over Fast FadingFast Fading MarginMinimum Signal Strength RequiredPenetration LossStd. dev. of Slow FadingEdge coverage ProbabilitySlow Fading MarginSHO Gain over Slow Fading

  • HUAWEI TECHNOLOGIES CO., LTD. Page 42All rights reserved

    Elements of WCDMA Uplink Budget 1.Max Power of TCH (dBm)

    For a UE, the maximum power of each traffic channel is usually the nominal total transmit power. There are many types of UE in a commercial network, so this parameters should be reasonably set in the link budget according to the specifications of a mainstream commercial cell phone and the requirement of the operator.

    Grade of UE power TS 25.101 v3.7.0 2001-066.2.1

    +2/-2dB+21dBm4

    +1/-3dB+24dBm3

    +1/-3dB+27dBm2

    +1/-3dB+33dBm1

    ToleranceNominal maximum output powerPower Class

  • HUAWEI TECHNOLOGIES CO., LTD. Page 43All rights reserved

    Elements of WCDMA Uplink Budget

    2. Body Loss (dB)For voice service, the body loss is 3 dB. Because the data service mainly involves reading and video,

    so the UE is relatively far from body, and the body loss is 0 dB.

    3. Gain of UE Tx Antenna (dBi) In general, assume that the receiver gain and transmitter

    gain of the UE antenna are both 0 dBi. 4. EIRP(dBm)

    UE EIRP (dBm) = UE Tx Power (dBm) - Body Loss (dB)+ Gain of UE Tx Antenna (dBi)

  • HUAWEI TECHNOLOGIES CO., LTD. Page 44All rights reserved

    Elements of WCDMA Uplink Budget 5. Gain of BS Rx Antenna (dBi)

    Kathrein 741794

    6.6kgWeight

    1302 mm / 155 mm / 69 mm

    dimensioning (Height / Width / Depth)

    >30dBFront-to-back ratio, co-polar

    >14dBSide lobe suppression for 1st side

    lobe above horizon

    Fixed, 2Electrical tilt

    Horizontal: 63

    Vertical:6.5HPBW (1920~2170MHz)

    18.5dBiGain

    +45, -45Polarization

    1710~2170MHz (dual band for DCS and

    UMTS)Frequency range

    Kathrein 741790

    5kgWeight

    1387 mmdimensioning (Height)Fixed, 0Electrical tilt

    Vertical: 7HPBW

    11dBiGain

    VerticalPolarization

    1920~2170MHzFrequency range

  • HUAWEI TECHNOLOGIES CO., LTD. Page 45All rights reserved

    Elements of WCDMA Uplink Budget 6. Cable Loss (dB)

    It includes the loss of the feeders and connectors between the cabinet top and the antenna connector.

    Lower jumper Connector Feeder Upper jumper Etc.

    Except for the feeder, the loss is relatively constant. Assume that the connecter loss is 0.8 dB.

    7/8-inch feeder: 6.1 dB / 100m for 2GHz 5/4-inch feeder: 4.5 dB / 100m for 2GHz

    Bracket

    Bracket

    Tilt adjuster

    Antenna

    Upper jumper

    Feeder

    Feeder windowLightning arrester

    Lower jumper

    Feeder fixing clip

    Feeder grounding clip

    Feeder installation

  • HUAWEI TECHNOLOGIES CO., LTD. Page 46All rights reserved

    Elements of WCDMA Uplink Budget 7. Noise Figure (dB)

    Noise figure (NF): It is used to measure the noise performance of an amplifier. It refers to the ratio of the inputSNR to the output SNR of the antenna.

    Thermal noise of receiver (unit bandwidth): PN = KTBWNF

    = -174 (dBm/Hz) + 10lg(3.84MHz / 1Hz) + NF(dB)= -108 (dBm/3.84MHz) + NF (dB)

    NF NF = = SNRSNRii / / SNRSNRoo= (S= (Sii / N/ Nii) / (S) / (Soo / N/ Noo))

  • HUAWEI TECHNOLOGIES CO., LTD. Page 47All rights reserved

    Elements of WCDMA Uplink Budget 8. Eb/No Required (dB)

    It is obtained through link simulation. It is related to the following:

    Configuration of receiver diversity

    Multi-path channel condition

    Bearer type

    9. Sensitivity of BS Receiver (dBm)Sensitivity of Receiver (dBm)

    = -174 (dBm/Hz) + NF (dB) + 10lg(3.84MHz/1Hz)+ required Eb/No (dB) - 10lg[3.84MHz/Rb(kHz)]

    = -174 (dBm/Hz) + NF (dB) + 10lg[1000 * Rb (kHz)] + Eb/No (dB)

  • HUAWEI TECHNOLOGIES CO., LTD. Page 48All rights reserved

    Elements of WCDMA Uplink Budget

    10. Background Noise Level (dBm)External electromagnetic interference sources:

    Wireless transmitters (GSM, microwave, radar, television station, and so)

    Automobile ignition

    Lightning

    For the planning for a specific area, it is recommended to estimate the local interference through noise test.

  • HUAWEI TECHNOLOGIES CO., LTD. Page 49All rights reserved

    Elements of WCDMA Uplink Budget 11. Penetration Loss (dB)

    Indoor penetration loss refers to the difference between the average signal strength outside the building and the average signal strength of one layer of the building.

    The penetration loss is related to building type, arrive angle of the radio wave, and so on. In the link budget, assume that the penetration loss is subject to the lognormal distribution. The penetration loss is indicated by average penetration loss and standard deviation.

    It is uneconomical to provide better indoor coverage through an outdoor BS. The indoor coverage shall be provided through a reasonable indoor coverage solution.

    In the actual construction of a commercial network, the penetration loss margin is usually specified by the operator in order to compare the planning results of different manufacturers.

  • HUAWEI TECHNOLOGIES CO., LTD. Page 50All rights reserved

    Elements of WCDMA Uplink Budget 12. Fast Fading Margin (dB)

    In the link budget, the demodulation performance of the used receiver is the simulation result based on the assumed ideal power control. In an actual system, because of the limited transmit power of the transmitter, non-ideal factors are introduced in the closed loop power control.

    Effect of power control margin on the uplink demodulation performance:

    The simulation shows the following: When the HeadRoom is large, the target Eb/No set in the outer loop power control is appropriate to the simulation result under the ideal power control. As the power margin decreases, the Eb/No gradually increases (if the power margin decreases by 1 dB, the required Eb/No increases by about 1 dB). If power control performance is almost not available, the BER/BLER cannot be ensured.

  • HUAWEI TECHNOLOGIES CO., LTD. Page 51All rights reserved

    Elements of WCDMA Uplink Budget 13. Edge coverage Probability

    When the transmit power of a UE hits the threshold, but the path loss does not meet the requirements for the lowest receive level, the link will be disconnected.

    For a UE at a distance of d, the link disconnection probability is as follows:

    (d) = Pmax_UE S_min 10lg(d)It refers to the difference between the average loss of the paths at a distance of d and the allowed maximum path loss for ensuring the connection.

    The average fading component is 0, and the standard variation is

    })(Pr{})lg(10_Pr{})lg(10_Pr{

    })(_Pr{)(Pr_

    minmax

    minmax

    minmax

  • HUAWEI TECHNOLOGIES CO., LTD. Page 52All rights reserved

    SF x ,( ) dnorm x 0, ,( ):=

    30 20 10 0 10 20 300

    0.02

    0.04

    0.06

    SF x 8,( )SF x 10,( )SF x 12,( )

    x

    SF_M x ,( ) pnorm x 0, ,( ):=

    20 16 12 8 4 0 4 8 12 16 200

    0.1

    0.2

    0.3

    0.4

    0.5

    0.6

    0.7

    0.8

    0.9

    1

    SF_M x 8,( )SF_M x 10,( )SF_M x 12,( )

    x

    Elements of WCDMA Uplink Budget 14. Slow Fading Margin (dB)

    Key point: Property of normal distribution.

    Slow Fading Margin (dB) = required edge coverage ProbabilityStd. dev. of Slow Fading (dB)

  • HUAWEI TECHNOLOGIES CO., LTD. Page 53All rights reserved

    Elements of WCDMA Uplink Budget

    15. Uplink Cell Load

    Uplink cell load is used to measure the uplink load of a cell.

    The higher the uplink cell load, the higher the uplink interference.

    If the uplink load is about 100% , the uplink interference becomes infinite, and the corresponding capacity is the limit capacity.

    ( ) ( ) ( ) +=+= N jjjN jUL WvREbvsNo

    iLi11

    11

  • HUAWEI TECHNOLOGIES CO., LTD. Page 54All rights reserved

    Elements of WCDMA Uplink Budget

    16. Uplink Interference Margin (dB)UL

    N

    jN

    TOT

    LPINoiseRise

    =

    ==

    1

    1

    1

    1

    1

    50% Load 50% Load 3dB3dB60% 60% LoadLoad 4dB4dB75% 75% LoadLoad 6dB6dB

  • HUAWEI TECHNOLOGIES CO., LTD. Page 55All rights reserved

    Elements of WCDMA Uplink Budget

    17. SHO Gain over Fast Fading (dB)The soft handover gain includes two parts:

    Multiple related soft handover branches lower the required margin for fading, which results in multi-cell gain.

    Gain for the link demodulation of the soft handover macro diversity combining gain.

    The SHO Gain over Fast Fading refer to the macro diversity combination gain.

    This value is obtained through simulation. The typical value is 1.5 dB.

  • HUAWEI TECHNOLOGIES CO., LTD. Page 56All rights reserved

    Elements of WCDMA Uplink Budget

    18.SHO Gain over Slow Fading (dB)As mentioned above, the soft handover gain

    includes two parts: Multiple irrelevant soft handover branches lower

    the required margin for fading, which results in multi-cell gain.

    Gain for the link demodulation of the soft handover marco diversity combination gain.

    The SHO Gain over Fast Fading refers to the macro diversity combining gain.

    This value is obtained through simulation.

  • HUAWEI TECHNOLOGIES CO., LTD. Page 57All rights reserved

    Elements of WCDMA Uplink Budget

    19. Minimum Signal Strength Required (dBm)After the interference factors and the factors

    degrading the performance are considered, the signal strength required by the correct demodulation is receiver sensitivity in the network.

    Minimum Signal Strength Required= Sensitivity of Receiver (dBm) - Gain of Antenna (dBi)+ Body Loss (dB) + Interference Margin (dB)+ Margin for Background Noise (dB) - SHO Gain over fast fading (dB) + Fast Fading Margin (dB)

  • HUAWEI TECHNOLOGIES CO., LTD. Page 58All rights reserved

    Elements of WCDMA Uplink Budget

    Summary: Cell edge path loss Based on the maximum path loss allowed by the link,

    the path loss at the cell edge can be calculated if the fading margin and soft handover gain for providing the required edge/area coverage probability and the penetration loss of indoor coverage are considered.

    Path Loss (dB) = [ EiRP (dBm) - Minimum Signal Strength Required (dBm) ]- Penetration Loss (dB) -Slow Fading Margin (dB) + SHO Gain over Slow Fading (dB)

  • HUAWEI TECHNOLOGIES CO., LTD. Page 59All rights reserved

    Section 1 Process of WCDMA Network PlanningSection 1 Process of WCDMA Network Planning

    Section 2 Uplink BudgetSection 2 Uplink Budget

    Section 3 Downlink BudgetSection 3 Downlink Budget

    Section 4 Coverage Enhancement TechnologiesSection 4 Coverage Enhancement Technologies

  • HUAWEI TECHNOLOGIES CO., LTD. Page 60All rights reserved

    Fundamental Principle

    Link Budget: Link Budget intends to estimate the system coverage by analyzing the factors of the propagation of the forward signal and reverse signal, in order to obtain the maximum propagation loss after certain communications quality is ensured.

    TX

    CombinerDuplexer

    Feeder

    RX

    Pout_BS

    Lc_BSLf_BS

    Ga_BSNodeB

    TX

    RX

    Pout_UE

    Ga_UEUE

    CombinerDuplexer

    PL_DLPL

    _UL

    Body Loss

    FadingMargin

    PenetrationLoss

  • HUAWEI TECHNOLOGIES CO., LTD. Page 61All rights reserved

    Algorithm PL_DL=Pout_BS Lf_BS+Ga_BS+Ga_UE +Ga_SHO Mpc Mf MI Lp

    Lb S_UE PL_DL: Maximum propagation loss of the downlink Pout_UE: Maximum transmit power of the traffic channel of the BS Lf_BS: Cable loss Ga_BS: Antenna gain of the BS; Ga_UE: Antenna gain of the MS Ga_SHO: Gain of soft handover Mpc: Margin for fast power control Mf: Slow fading margin (related to the propagation environment) MI: Interference margin (related to the designed system capacity) Lp: Penetration loss of a building (used if indoor coverage is required) Lb: Body loss S_UE: Sensitivity of UE receiver (related to factors such as service and

    multi-path condition)

    Downlink (forward)Downlink (forward)

  • HUAWEI TECHNOLOGIES CO., LTD. Page 62All rights reserved

    Elements of WCDMA Downlink Budget Max Power of TCHCable LossGain of BS Tx AntennaEIRPGain of UE Rx AntennaBody LossNoise Figure (UE)Required Eb/No (UE)Sensitivity of UE Receiver DL Cell LoadingInterference MarginBackground Noise Level

    SHO Gain over Fast Fading

    Fast Fading Margin

    Minimum Signal Strength Required

    Penetration Loss

    Std. dev. of Slow Fading

    Edge coverage Probability

    Slow Fading Margin

    SHO Gain over Slow Fading

  • HUAWEI TECHNOLOGIES CO., LTD. Page 63All rights reserved

    Elements of WCDMA Downlink Budget 1.Downlink Cell Load

    Downlink cell load factor is defined in two ways: Downlink cell load at the receiver:

    This definition is similar to that of the uplink cell load: The higher the downlink cell load, the higher the cell transmit power,

    and the higher the receiver interference. When the downlink cell load is 100% , the corresponding capacity is

    the limit capacity of the downlink. Downlink cell load at the receiver: The ratio of the current cell transmit

    power to the maximum BS transmit power. Characteristics: The higher the downlink cell load, the higher the cell transmit power.

    The downlink cell load is related to service type, UE receiver performance, cell size, and BS capability.

    ( ) ( )

    +=

    N

    jj

    jjjDL vWR

    EbvsNoi1

    1

    Currently, the later definition is used in the link budget tool.Currently, the later definition is used in the link budget tool.

  • HUAWEI TECHNOLOGIES CO., LTD. Page 64All rights reserved

    : 1.78

    Elements of WCDMA Downlink Budget 2.Downlink Interference Margin (dB)

    Downlink interference at UE receiver:

    The downlink load factor is:

    The link budget tool uses the following typical values:

    orthogonal factor : It is obtained through simulation. It is related to environment type and cell radius.

    Cell edge adjacent-cell interference factor

    N

    N

    N

    nnj

    T

    j

    Tj

    N

    total

    P

    PPL

    PPL

    P

    PIjNoiseRise

    ++

    ==

    =1

    ,

    1)1()(

    jDLf , =

    N

    n nj

    ownj

    PLPL

    1 ,

    ,

    j

    ( ) ( )=

    +=

    J

    jjDLj

    jjjobDL fW

    RVNE1

    ,)1(/ ,where = ,where =

  • HUAWEI TECHNOLOGIES CO., LTD. Page 65All rights reserved

    Section 1 Process of WCDMA Network PlanningSection 1 Process of WCDMA Network Planning

    Section 2 Uplink BudgetSection 2 Uplink Budget

    Section 3 Downlink Budget Section 3 Downlink Budget

    Section 4 Coverage Enhancement TechnologiesSection 4 Coverage Enhancement Technologies

  • HUAWEI TECHNOLOGIES CO., LTD. Page 66All rights reserved

    Tower Mounted Amplifier (TMA)

    TMA

    A TMA locate the position under the antenna

    A TMA is Low noise amplifierA TMA helps to improve the

    uplink receive sensitivity and enhances the uplink coverage

    A TMA usually has 0.7dB loss in the downlink.

  • HUAWEI TECHNOLOGIES CO., LTD. Page 67All rights reserved

    Academic calculation about TMAAcademic calculation about TMA improve the uplink receive sensitAcademic calculation about TMA improve the uplink receive sensitivityivity

  • HUAWEI TECHNOLOGIES CO., LTD. Page 68All rights reserved

    The example of academic calculation about TMA improve the uplink receive sensitivity

    Receiver Chain Noise FigureWithout TMA: 2.433+2.2 dBWith TMA 1.57 dB

    The example of academic calculation about TMA

    2.2NodeB

    -2.4332.4337/8"Cable30m + 0.6dB Connector Loss

    121.45TMA

    GainNoise FigureEquipment

    Gain 3.063dB for uplink when using TMAGain 3.063dB for uplink when using TMA

  • HUAWEI TECHNOLOGIES CO., LTD. Page 69All rights reserved

    4-antennas Reception Diversity

    4Antenna reception diversity 4Antenna reception diversity has

    two typesTwo Cross-polarization

    antennasFour antennas

    4Antenna reception diversity helps to improve the uplink reception performance

    Improve the uplink coverage and capacity performance

    4Antenna reception diversity need equipment support

  • HUAWEI TECHNOLOGIES CO., LTD. Page 70All rights reserved

    4-antennas Reception Diversity

    4RxDiv principle diversity gain

    Resist fast fadingCorrelation combinationGain relates to multi-

    path ,service ,speed, antenna performance

    2RxDiv> 4RxDivReduce the requirement of

    Eb/No

  • HUAWEI TECHNOLOGIES CO., LTD. Page 71All rights reserved

    4-antennas Reception Diversity

    Compared with a double-antenna reception diversity, 4-antenna reception diversity requires lower Eb/No.

    Gain of 4-antenna reception diversity (compared with double-antenna reception diversity)

    1.391.772.5RA120Rural area

    RA120

    TU3

    TU3

    Channel

    1.77

    1.73

    1.73

    Capacity-based gain

    1.39

    1.37

    1.37

    Coverage-based gain

    2.5Suburb

    2.4Common urban

    area

    2.4High-density urban area

    Eb/No improvement Area

  • www.huawei.com

    Thank You