Home >Documents >TX RX Diversity

TX RX Diversity

Date post:26-Dec-2015
Category:
View:38 times
Download:5 times
Share this document with a friend
Description:
Tx-Rx diversity
Transcript:
  • RAN

    TX/RX Diversity

    Issue DraftDate 2008-03-20Part Number

    Huawei Proprietary and ConfidentialCopyright Huawei Technologies Co., Ltd

  • Huawei Technologies Co., Ltd. provides customers with comprehensive technical support and service. For anyassistance, please contact our local office or company headquarters. Huawei Technologies Co., Ltd.Address: Huawei Industrial Base

    Bantian, LonggangShenzhen 518129People's Republic of China

    Website: http://www.huawei.comEmail: [email protected] Copyright Huawei Technologies Co., Ltd. 2008. All rights reserved.No part of this document may be reproduced or transmitted in any form or by any means without prior writtenconsent of Huawei Technologies Co., Ltd. Trademarks and Permissions

    and other Huawei trademarks are the property of Huawei Technologies Co., Ltd.All other trademarks and trade names mentioned in this document are the property of their respective holders. NoticeThe information in this document is subject to change without notice. Every effort has been made in thepreparation of this document to ensure accuracy of the contents, but the statements, information, andrecommendations in this document do not constitute a warranty of any kind, express or implied.

    Huawei Proprietary and ConfidentialCopyright Huawei Technologies Co., Ltd

  • Contents

    1 Change History of TX/RX Diversity.......................................................................................1-12 Introduction to TX/RX Diversity.............................................................................................2-13 Technical Description of TX/RX Diversity............................................................................3-1

    3.1 TX/RX Diversity Parameters..........................................................................................................................3-23.2 RX Diversity Algorithms................................................................................................................................3-33.3 TX Diversity Algorithms................................................................................................................................3-8

    4 Implementing TX/RX Diversity..............................................................................................4-14.1 Enabling TX/RX Diversity..............................................................................................................................4-24.2 Reconfiguring TX/RX Diversity Parameters..................................................................................................4-34.3 Disabling TX/RX Diversity............................................................................................................................4-3

    5 Maintenance Information About TX/RX Diversity.............................................................5-16 Reference Documents About TX/RX Diversity....................................................................6-1

    RANTX/RX Diversity Contents

    Issue Draft (2008-03-20) Huawei Proprietary and ConfidentialCopyright Huawei Technologies Co., Ltd

    i

  • Figures

    Figure 3-1 4-way RX diversity of one sector in the BTS3812E..........................................................................3-7Figure 3-2 4-way RX diversity of one sector in the DBS3800............................................................................3-8Figure 3-3 Structure of SCH transmitted in TSTD..............................................................................................3-8Figure 3-4 STTD encoder for QPSK....................................................................................................................3-9Figure 3-5 STTD encoder for 16QAM.................................................................................................................3-9Figure 3-6 Transmitter and receiver in closed loop transmit diversity mode.....................................................3-10Figure 3-7 Hardware connections for 2-way RX diversity and TX diversity for the BTS3812E......................3-16Figure 3-8 Hardware connections for 2-way RX diversity and TX diversity for the DBS3800........................3-17

    RANTX/RX Diversity Figures

    Issue Draft (2008-03-20) Huawei Proprietary and ConfidentialCopyright Huawei Technologies Co., Ltd

    iii

  • Tables

    Table 1-1 Document and product versions...........................................................................................................1-1Table 2-1 NEs involved in TX/RX diversity........................................................................................................2-2Table 2-2 RAN products and related versions......................................................................................................2-2Table 3-1 TX/RX diversity parameters................................................................................................................3-2

    RANTX/RX Diversity Tables

    Issue Draft (2008-03-20) Huawei Proprietary and ConfidentialCopyright Huawei Technologies Co., Ltd

    v

  • 1 Change History of TX/RX DiversityThis describes the changes in different document versions.

    Document and Product VersionsTable 1-1 Document and product versions

    DocumentVersion

    RAN Version RNC Version NodeB Version

    Draft(2008-03-20)

    10.0 V200R010C01B050 V100R010C01B045

    There are two types of changes, which are defined as follows:l Feature change: refers to the change in the TX/RX diversity feature of a specific product

    version.l Editorial change: refers to the change in the information that was inappropriately described

    or the addition of the information that was not described in the earlier version.

    Draft (2008-03-20)This is the draft release of RAN10.0.

    RANTX/RX Diversity 1 Change History of TX/RX Diversity

    Issue Draft (2008-03-20) Huawei Proprietary and ConfidentialCopyright Huawei Technologies Co., Ltd

    1-1

  • 2 Introduction to TX/RX DiversityThe signals on radio channels reach the receiver through multiple paths. If the signals arecombined by the receiver, they are capable of anti-fading.

    IntroductionDefinitionDiversity is a transmission technique to enhance the system performance by receiving multipathsignals and then combining them into one.In the WCDMA system, diversity can be performed in two directions:l Receive diversity (RX diversity)l Transmit diversity (TX diversity)Based on the number of antennas, receive diversity is of two types:l 2-way receive diversityl 4-way receive diversityBased on the feedback, TX diversity is of two types:l Open loop transmit diversity (without feedback)l Closed loop transmit diversity (with feedback)The open loop transmit diversity can be further categorized into:l Space Time Transmit Diversity (STTD)l Time Switched Transmit Diversity (TSTD)PurposesDiversity can improve the performance of RX channels and lower the requirement for the SIRof downlink signals and uplink signals.

    AvailabilityNetwork Elements InvolvedTable 2-1 lists the Network Elements (NEs) involved in TX/RX diversity.

    RANTX/RX Diversity 2 Introduction to TX/RX Diversity

    Issue Draft (2008-03-20) Huawei Proprietary and ConfidentialCopyright Huawei Technologies Co., Ltd

    2-1

  • Table 2-1 NEs involved in TX/RX diversityUE NodeB RNC MSC

    ServerMGW SGSN GGSN HLR

    NOTE

    l : not involvedl : involved

    RX diversity requires the NodeB to provide enough RF channels and demodulation resourcesthat can match the number of diversity antennas. It has no special requirements for the RNC orUE.TX diversity requires the NodeB to provide RF channels two times those provided in no TXdiversity mode. In addition, TX diversity requires the NodeB to support STTD, TSTD, and CP1.In TX diversity mode, the UE must support diversity reception, STTD, TSTD, and CP1. Thisdiversity mode has no special requirements for the RNC.Software ReleasesTable 2-2 describes the versions of RAN products that support TX/RX diversity.

    Table 2-2 RAN products and related versionsProduct VersionRNC BSC6800 V100R002 and later releases

    BSC6810 V200R009 and later releasesNodeB DBS3800 V100R006 and later releases

    BTS3812A V100R005 and later releasesBTS3812EBTS3812AE V100R008 and later releases

    NOTE

    l RNC V100R002 and later releases support TSTD and STTD. RNC V100R008 and later releasessupport closed loop transmit diversity mode 1 (CP1).

    l RX diversity is performed only by the NodeB to improve the performance of RX channels. It doesnot involve the RNC or UE.

    ImpactImpact on System PerformanceTX diversity can improve the performance of UE in special circumstances, especially wherethere is unobvious multipath effect and the UE moves slowly. In such a scenario, capacity and

    2 Introduction to TX/RX DiversityRAN

    TX/RX Diversity

    2-2 Huawei Proprietary and ConfidentialCopyright Huawei Technologies Co., Ltd

    Issue Draft (2008-03-20)

  • coverage can be obviously increased, and CAPEX and OPEX can be reduced, under thecondition that the QoS is guaranteed.TX diversity can improve the system performance significantly, although not all the users canexperience it, limited by various scenarios and motion velocities. If different TX modes,however, are set for different cell circumstances, handovers between the cells with different TXmodes become complex. As a result, the system performance may be degraded.Impact on Other FeaturesNone.

    CapabilitiesNone.

    RANTX/RX Diversity 2 Introduction to TX/RX Diversity

    Issue Draft (2008-03-20) Huawei Proprietary and ConfidentialCopyright Huawei Technologies Co., Ltd

    2-3

  • 3 Technical Description of TX/RX DiversityAbout

Popular Tags:

Click here to load reader

Embed Size (px)
Recommended