CE Efficiency Improvement for HSUPA TTI 2ms

CE Efficiency Improvement for HSUPA TTI 2msContents

3.4.4 CE Efficiency Improvement for HSUPA TTI 2ms

WCDMA RAN

CE Efficiency Improvement for HSUPA TTI 2msFeature Parameter DescriptionIssue 01

Date 20140430

HUAWEI TECHNOLOGIES CO., LTD.

Copyright © Huawei Technologies Co., Ltd. 2014. All rights reserved.No part of this document may be reproduced or transmitted in any form or by any means without prior written consent of HuaweiTechnologies Co., Ltd.

Trademarks and Permissions

and other Huawei trademarks are trademarks of Huawei Technologies Co., Ltd.All other trademarks and trade names mentioned in this document are the property of their respective holders.

NoticeThe purchased products, services and features are stipulated by the contract made between Huawei and the customer. All or part of theproducts, services and features described in this document may not be within the purchase scope or the usage scope. Unless otherwisespecified in the contract, all statements, information, and recommendations in this document are provided "AS IS" without warranties,guarantees or representations of any kind, either express or implied.The information in this document is subject to change without notice. Every effort has been made in the preparation of this document toensure accuracy of the contents, but all statements, information, and recommendations in this document do not constitute a warranty ofany kind, express or implied.

Huawei Technologies Co., Ltd.

Address: Huawei Industrial Base Bantian, Longgang Shenzhen 518129 People's Republic of China

Website: http://www.huawei.com

Email: [email protected]

3.4.4 Contents

1 About This Document1.1 Scope1.2 Intended Audience1.3 Change History1.4 Differences Between Base Station Types

2 Overview2.1 Background2.2 Introduction2.3 Benefits

3 Technical Description3.1 Principles3.2 Feature Impacts3.2.1 Dynamic CE Resource Management3.2.2 Admission CE Consumption for HSUPA UEs with a 2 ms TTI

4 Related Features5 Network Impact6 Engineering Guidelines6.1 When to Use CE Efficiency Improvement for HSUPA TTI 2ms6.2 Required Information6.3 Deployment6.3.1 Requirements6.3.2 Data Preparation6.3.3 Activation6.3.4 Activation Observation6.3.5 Deactivation6.4 Performance Monitoring6.5 Parameter Optimization6.6 Troubleshooting

7 Parameters

7 Parameters8 Counters9 Glossary10 Reference Documents

1 About This Document

1.1 ScopeThis document describes WRFD160205 CE Efficiency Improvement for HSUPA TTI 2ms, including the technical principles, relatedfeatures, network impact, and engineering guidelines.

This document applies to the following types of NEs.

NE Type Model

RNC BSC6900 and BSC6910

NodeB Macro 3900 series macro base stations: BTS3900, BTS3900A, BTS3900L, BTS3900AL,DBS3900, and BTS3900C3800 series macro base stations: DBS3800, BTS3812E, and BTS3812AE

Micro BTS3902E

LampSite DBS3900 LampSite

1.2 Intended AudienceThis document is intended for personnel who:

Need to understand the features described herein

Work with Huawei products

1.3 Change HistoryThis section provides information about the changes in different document versions. There are two types of changes, which are definedas follows:

Technical change

Changes in features of a specific product version

Editorial changeChanges in wording or addition of information that was not described in the earlier version

RAN16.0 01 (20140430)

This issue includes the following changes.

Change Type Change Description Parameter Change

Technical change None None

Editorial change Optimized the document description. None

RAN16.0 Draft B (20140228)

This issue includes the following changes.

Change Type Change Description Parameter Change

Technical change None None

Editorial change Added the descriptions about the feature andfunction differences between NodeBs ofdifferent types. For details, see section 1.4

None

Differences Between Base Station Types.

RAN16.0 Draft A (20140120)

This document is created for RAN16.0.

1.4 Differences Between Base Station Types

Feature Supported by Macro, Micro, and LampSite base stations

Feature ID Description Supported by Base StationControllers

Supported byMacro basestations

Supported by Micro basestations

LampSite

BSC6900 BSC6910 BTS3803E BTS3902E

WRFD160205

CE EfficiencyImprovementfor HSUPATTI 2ms

Y Y Y N Y Y

NOTE:"Y" indicates that this feature is supported. "N" indicates that this feature is not supported. "N/A" indicates that this feature is notdependent on the NE.

The feature described in this document is implemented in the same way on macro, micro, and LampSite base stations.

2 Overview

2.1 BackgroundChannel element (CE) resources are a type of NodeB resources. The number of CEs supported by a NodeB is determined by thecapabilities of its baseband boards. Downlink CEs are used for encoding, spreading, and modulation. Uplink CEs are used fordemodulation and decoding.

CE resources are crucial for HSUPA UEs with a 2 ms transmission time interval (TTI) to experience high rates and short servicedelays. An HSUPA UE with a 2 ms TTI consumes much more uplink CE resources than an HSUPA UE with a 10 ms TTI. If CEresources are insufficient, HSUPA UEs with a 2 ms TTI cannot access the network unless they use a 10 ms TTI.

CE resource usage is somewhat low on live networks. This is because the traffic model has been changed as a result of theincreasingly high penetration rate of smartphones and thereby an increased number of online HSUPA users. Although the data rate ofthese users is low (at around 20 kbit/s), they still consume a considerable amount of CE resources.To improve CE efficiency and adapt to the reality of today's traffic models, Huawei introduces the WRFD160205 CE EfficiencyImprovement for HSUPA TTI 2ms feature.

2.2 IntroductionThis feature improves CE efficiency for HSUPA UEs with a 2 ms TTI. With this feature, an HSUPA UE consumes a minimum of oneCE to keep online and transmit data at a minimum uplink rate of 20 kbit/s.

2.3 BenefitsThis feature provides the following benefits when CE resources are insufficient:

Allows more HSUPA UEs with a 2 ms TTI to be admitted.

Increases the uplink throughput.

3 Technical Description

3.1 Principles

With CE Efficiency Improvement for HSUPA TTI 2ms, an HSUPA UE with a 2 ms TTI uses a single HARQ process to transmit oneRLC PDU with a default size of 40 bytes in each TTI. To implement this, the NodeB sends an absolute grant (AG) message todeactivate the other seven HARQ processes.

Figure 31 shows the technical principles.

Figure 31 Technical principles of CE Efficiency Improvement for HSUPA TTI 2ms

Figure 32 shows the CE resources consumed in each TTI before this feature is enabled. The active HARQ process uses spreadingfactor (SF) 4 and consumes eight CEs, while each the other inactive HARQ process consumes one CE. The average number of CEsconsumed by a HARQ process is 1.875.

Figure 32 CE consumption before this feature is enabled

After this feature is enabled, each HARQ process (active or inactive) consumes only one CE, as shown in Figure 33.

Figure 33 CE consumption after this feature is enabled

NOTE:CE consumption of UEs not using the single HARQ process depends on the requirement of the SF used by each TTI. For moreinformation about how to calculate CE consumption for such UEs, see CE Resource Management Feature Parameter Description.

To enable this feature, run the NodeB MML command SET NODEBALGPARA with CEIMPROVEMENT2MSSW set to ON(ON).

3.2 Feature ImpactsCE Efficiency Improvement for HSUPA TTI 2ms affects dynamic CE scheduling and CE admission algorithm as follows:

In dynamic CE scheduling, the scheduler can configure HSUPA UEs with a 2 ms TTI to use a single HARQ process totransmit one RLC PDU in each TTI when uplink data rate required by the UEs is 20 kbit/s or lower, thereby reducing CEconsumption.

Each HSUPA UE with a 2 ms TTI consumes only one admission CE.

3.2.1 Dynamic CE Resource ManagementThe dynamic CE algorithm allocates CE resources to each HSUPA UE based on available CE resources, UE's data transmissionrequirements, and user differentiation. When CE resources are sufficient, more CEs are allocated to UEs that require rate upgrade. IfCE resources become insufficient, a rate downgrade is performed. To ensure that a UE is online, the downgraded rate must not belower than 160 kbit/s, which is the minimum requirement when a UE uses all the eight active HARQ processes to transmit one RLCPDU. When CE Efficiency Improvement for HSUPA TTI 2ms is enabled, the minimum rate of an HSUPA UE with a 2 ms TTI at the RLClayer can be reduced from 160 kbit/s to 20 kbit/s, as such a UE can use a single HARQ process to transmit one RLC PDU in eachTTI.

CE Efficiency Improvement for HSUPA TTI 2ms also increases the differentiation between highpriority and lowpriority UEs when CEresources are insufficient. Highpriority HSUPA UEs with a 2 ms TTI can enjoy a maximum rate of 5.44 Mbit/s at the RLC layer.Therefore, the rate differentiation ratio between highpriority and lowpriority UEs is increased from 34:1 (5440:160) to 272:1 (5440/20).Figure 34 shows dynamic CE resource management when CE Efficiency Improvement for HSUPA TTI 2ms is enabled. For detaileddescription about dynamic CE resource management, see HSUPA Feature Parameter Description. For information about CEconsumption for a 2msTTI HSUPA service, see Table 34 and Table 36 in CE Resource Management Feature Parameter Description.

Figure 34 Dynamic CE resource management when CE Efficiency Improvement for HSUPA TTI 2ms is enabled

In addition to CE resource congestion scenarios, you can also enable a UE to use a single HARQ process by setting theInitSingleHARQSW parameter to ON in the SET NODEBALGPARA command when the CE Efficiency Improvement for HSUPA TTI2ms is enabled. After the switch is enabled, the NodeB sends a scheduling grant to all newly admitted HSUPA UEs with a 2 ms TTI sothat they use a single HARQ process to transmit one RLC PDU in each TTI at 20 kbit/s. When CE resources are sufficient, the NodeBallows UEs that require higher data rates to use all the eight HARQ processes to transmit data. The NodeB learns that a UE requireshigher data rate when the happy bit of the UE transmitted on the EDCH Dedicated Physical Control Channel (EDPCCH) is "unhappy"and the value of Total EDCH Buffer Status (TEBS) in Segmentation Indication (SI) field is larger than or equal to 20 kbit/s. The UE thenuses all the eight HARQ processes to transmit data even though it no longer requires such a high rate. This situation lasts until the CEresources become insufficient and the NodeB instructs the UE to use a single HARQ process to transmit the data.This initial single HARQ function is recommended for NodeBs with insufficient CE resources and a large number of UEs that require alow data rate (20 kbit/s). Using this function restricts the instantaneous rate of UEs and therefore increases the uplink delay.

If the SrbChlTypeRrcEffectFlag(BSC6900,BSC6910) parameter is set to TRUE, the SRB over EDCH switch takes effect during anRRC connection establishment and the initial single HARQ function does not take effect during a RAB setup.

3.2.2 Admission CE Consumption for HSUPA UEs with a 2 ms TTITable 31 describes admission CE consumption for HSUPA UEs with a 2 ms TTI.

In versions earlier than RAN10.0, dynamic CE resource allocation is not supported and admission CE resources forHSUPA UEs are calculated based on the maximum bit rate (MBR). Each 2 ms TTI HSUPA UE consumes eight or moreCEs.

For information about the WRFD010638 Dynamic CE Resource Management feature, see HSUPA Feature ParameterDescription.

For information about the WRFD140212 CE Overbooking feature, see CE Overbooking Feature Parameter Description.

After the CE Efficiency Improvement for HSUPA TTI 2ms feature introduced in RAN16.0 is enabled, one CE suffices forcontinuous data transmission by a 2 ms TTI HSUPA UE. Therefore, only one CE is required for the 2 ms TTI HSUPA UE.

Table 31 Admission CE consumption

Feature Version Number of Required Admission CEs

CE Consumption Calculated Based on RAN10.0 andearlier versions

≥ 8

Dynamic CE Resource Management RAN10.0 8

CE Overbooking RAN14.0 28

CE Efficiency Improvement for HSUPA TTI2ms

RAN16.0 1

CE Efficiency Improvement for HSUPA TTI 2ms requires CE Overbooking, which allows the NodeB to calculate consumed admissionCE resources of admitted UEs and report the results to the RNC through the common measurement report. The RNC then performsadmissionCEbased call access control (CAC), load reshuffling (LDR), and TTI switching.

Only the WBBPf and UBBPd boards support CE Efficiency Improvement for HSUPA TTI 2ms. An uplink resource group may include

WBBPf and UBBPd boards that support this feature and others boards that do not. In sites enabled with this feature, only some of the2 ms TTI UEs can have services established on the WBBPf and UBBPd boards, whereas other 2 ms TTI UEs have servicesestablished on the other boards. Admission CE consumption is calculated, respectively, for these two types of UEs as follows:

For 2 ms TTI HSUPA UEs with services established on the WBBPf and UBBPd boards, they consume only one CE aswhat a 10 ms TTI UE does. Therefore, they will not be switched to use a 10 ms TTI when CE resources are insufficient. TheNodeB informs the RNC that these UEs do not support admissionCEbased or CEconsumptionbased TTI adjustmentsusing the private fields in the RL Setup Response, RL Reconfiguration Response Ready, or RL Add Response messages.

For 2 ms TTI HSUPA UEs with service established on other boards, admission CE consumption is calculated based on theactual UE data rate, minimum number of CEs reserved for 2 ms TTI UEs enabled with CE Overbooking, data rate requiredby the guaranteed bit rate (GBR) and for transmitting one RLC PDU. Therefore, these UEs will be switched to use a 10 msTTI when CE resources are insufficient.

4 Related Features

Prerequisite Features

WRFD010638 Dynamic CE Resource Management

WRFD140212 CE Overbooking

Mutually Exclusive Features

None

Impacted Features

WRFD010695 UL Layer 2 Improvement

When UL Layer 2 Improvement is enabled, the active HARQ process of a UE can use SF8 at most and the minimum RLCrate can be further reduced to 15 kbit/s.

AdmissionCEbased dynamic TTI adjustment for a single BE service over HSUPA

When admissionCEbased dynamic TTI adjustment for a single BE service over HSUPA is enabled,

HSUPA UEs with a 2 ms TTI with services established on the WBBPf or UBBPd board cannot be switched touse a 10 ms TTI if uplink CE resources become insufficient.

HSUPA UEs with a 10 ms TTI with services established on the WBBPf or UBBPd board can be switched to usea 2 ms TTI if uplink CE resources become insufficient.

For HSUPA UEs with a 2 ms TTI and newly admitted UEs whose services are established on the WBBPf orUBBPd board, 2 msto10 ms TTI switching is not performed if uplink CE resources become insufficient.

The reason is as follows:

The minimum RLC rate for 10 ms TTI HSUPA UEs is 32 kbit/s. If the CE Efficiency Improvement for HSUPA TTI 2msfeature is disabled, the minimum RLC rate for 2 ms TTI HSUPA UEs is 160 kbit/s. Therefore, when CEs are limited, TTIneeds to be changed from 2 ms to 10 ms to decrease CE consumption. After the CE Efficiency Improvement for HSUPATTI 2ms feature is enabled, HSUPA UEs with a 2 ms TTI can transmit data by using only one CE, which is the same asthat for HSUPA UEs with a 10 ms TTI. As a result, a 2 msto10 ms TTI switching is not required when uplink CE resourcesare insufficient.

For details about the function for admission CEbased dynamic TTI adjustment of BE services, see HSUPA TTI SelectionFeature Parameter Description.

WRFD010686 CPC DTX / DRX

When both the CE Efficiency Improvement for HSUPA TTI 2ms and CPC features are enabled, ensure that both the valuesof cycle1 and cycle2 configured for CPC UEs are 8 or multiples of 8, so as to keep the single HARQ function compatiblewith the DTX function. If the parameters configured for CPC UEs do not meet certain conditions, the UTRAN willautomatically identify CPC UEs, and configure cycle1 as 8 and cycle2 as 16. This function is introduced in RNC runningR16SPC630 and NodeB running R16SPC180, before when CPC UEs do not support the single HARQ function.

5 Network Impact

System Capacity

Increased number of HSUPA UEs with a 2 ms TTI

When compared with CE Overbooking, this feature further increases the number of HSUPA UEs with a 2 ms TTI that needto continuously transmit a large amount of data by two to eight times when CE resources are insufficient.

Higher HSUPA cell throughputIf you enable HSUPA UEs with a 2 ms TTI requiring a low data rate to use a single HARQ process from the beginning totransmit data in a cell loaded normally, UEs with data transfer requirements can use more CE resources, which increasesthe uplink throughput. The increased throughput depends on the number of HSUPA UEs with a 2 ms TTI requiring a lowdata rate and the number of such UEs that use a single HARQ process to transmit data.

Network Performance

When compared with CE Overbooking, this feature further decreases the amount of admission CE resources consumed by HSUPAUEs with a 2 ms TTI since they only use one admission CE. The admission CE consumption for such UEs can now be preciselyevaluated based on the number of UEs on the live network. With CE Overbooking, admission CE consumption for UEs with a 10 msTTI can be precisely evaluated based on the rate required for transmitting one RLC PDU. CE resources for R99 UEs are assigned andconsumed in a fixed manner.

If the uplink CE resources are insufficient and admissionCEbased dynamic TTI adjustment is not enabled, this feature allows moreUEs to be admitted, increasing the cell access success rate.

When this feature is enabled together with admissionCEbased and CEconsumptionbased dynamic TTI adjustment, if CE resourcesbecome insufficient, 2msto10ms TTI switching is not performed on HSUPA UEs with a 2 ms TTI. As a result, a single cell servesmore HSUPA UEs with 2 ms TTIs and the number of times TTI switching is triggered decreases.When this feature is enabled, the number of times HSUPA UEs experience service drops due to poor coverage may increase becausea 2 ms TTI provides weaker coverage than a 10 ms TTI. You are advised to enable coveragebased dynamic TTI adjustment to preventthis situation from occurring.

When compared with an HSUPA UE with a 2 ms TTI that uses all the eight HARQ processes to transmit data, an HSUPA UE with a 2ms TTI that uses a single HARQ process has a lower peak rate. Therefore, the service delay of such UEs may be prolonged.

6 Engineering Guidelines

6.1 When to Use CE Efficiency Improvement for HSUPA TTI 2msThis feature is recommended for NodeBs where,

HSUPA UEs that support a 2 ms TTI account for more than 60% of all HSUPA UEs.

Admission CE congestion still occurs after the CE Overbooking feature is enabled.

Access requests initiated by UEs with a 2 ms TTI are denied or these UEs are switched to use a 10 ms TTI.

Consumed CE resources account for 70% of all configured CE resources for the NodeB.

6.2 Required InformationYou must collect the values of the counters listed in the following table.

Collect the values of the following counters on the RNC:

VS.HSUPA.UE.Mean.CAT1.4: Average Number of HSUPA UEs with Category 14 in a Cell

VS.HSUPA.UE.Mean.CAT5~VS.HSUPA.UE.Mean.CAT9: Average Number of HSUPA UEs with Category 5 in aCell~Average Number of HSUPA UEs with Category 9 in a Cell

HSUPA UEs that support a 2 ms TTI account for more than 60% of all HSUPA UEs in a NodeB if the following inequality istrue:

∑VS.HSUPA.UE.Mean.CAT5~9)/(VS.HSUPA.UE.Mean.CAT1.4+(∑VS.HSUPA.UE.Mean.CAT5~9)≥ 60%

Collect the values of the following counters on the RNC. If any of the following counters has a value other than 0, accessdenial caused by insufficient admission CE resources occurred in the NodeB.

VS.RRC.Rej.ULCE.Cong: Number of RRC Connection Rejects for Cell (UL CE Resource Congestion)

VS.RAB.FailEstabCS.ULCE.Cong: Number of Failed CS RAB Establishments for Cell (UL CE Congestion)

VS.RAB.FailEstabPS.ULCE.Cong: Number of Failed PS RAB Establishments for Cell (UL CE Congestion)

VS.HSUPA.RAB.FailEstab.ULCE.Cong: Number of Failed HSUPA Service Establishments Due to UL CEInsufficiency for Cell

Collect the values of the following counters on the RNC. If either of the following counters has a value other than 0, 2msto

10ms TTI switching caused by insufficient admission CE resources occurred in the NodeB.

VS.HSUPA.TTI2to10.ADMCE.Succ: Number of Successful TTI Switchovers Based on Admitted CEs During RBReconfiguration in a Cell(2ms to 10ms)

VS.HSUPA.RABEstabTTI10ms.AdmCE.Succ: Number of Successful RAB Establishments Initiated by HSUPA2ms UEs with a 10 ms TTI Due to Congestion of Admitted CEs in a Cell

Collect the values of the following counters on the RNC and NodeB:

VS.NodeB.ULCreditUsed.Mean: Average NodeB Uplink Credit Usage When CE Overbooking Is Enabled forNodeB (RNC)

VS.LC.ULCreditUsed.Mean: Mean Usage of UL Credit for Cell (RNC)

VS.LC.ULCreditAvailable.Shared: Number of UL CEs configured for a shared group (NodeB)

If CE Overbooking is enabled, admissionCE congestion is about to occur if the following inequality is true:(VS.NodeB.ULCreditUsed.Mean/2)/VS.LC.ULCreditAvailable.Shared ≥ 70%

If CE Overbooking is not enabled, admissionCE congestion is about to occur if the following inequality is true:

(∑VS.LC.ULCreditUsed.Mean/2)/VS.LC.ULCreditAvailable.Shared ≥ 70%

6.3 Deployment

6.3.1 Requirements

Other Features

See "4 Related Features" in Impacted Features.

Hardware

The 3900 series base stations must be configured with the WBBPf or UBBPd board. The WBBPa board must not be contained in anydownlink resource groups within a NodeB.You can run the NodeB MML command LST BASEBANDEQM to check the baseband boards included in the downlink resourcegroups and run the NodeB MML command DSP BRDMFRINFO to query the type of a baseband board.

The BTS3803E supports CE Efficiency Improvement for HSUPA TTI 2ms.The DBS3800, BTS3812E, BTS3812A, BTS3812AE, and BTS3902E do not support CE Efficiency Improvement for HSUPA TTI 2ms.

License

For details about how to activate the license, see License Management Feature Parameter Description.

If RAN Sharing or MOCN is enabled, the licensed value is allocated among the primary and secondary operators according to the valueof the "License Allocation for Multiple Operators" parameter.

Feature ID Feature Name License ControlItem

License ControlName

LicenseControlItemName onU2000GUI

NE LicenseAllocation forMultipleOperators

SalesUnit

WRFD160205

CE EfficiencyImprovementfor HSUPA TTI2ms

LQW9CEEFF01 CE EfficiencyImprovementfor HSUPA TTI2ms (perNodeB)

HSUPA2ms TTICEefficiencyEnhanced

NodeB Method 1 perNodeB

Method 1: Some license control items, for example, Dynamic CE Function (per NodeB), can be allocated only through the commongroup. For NodeB license allocation among multiple operators, see License Management Feature Parameter Description.

Others

The UE is of HSUPA category 6 or higher.There are no nonscheduling services in the uplink.

The maximum size of an RLC PDU is 336 bits.

6.3.2 Data PreparationTable 61 lists the data to prepare before activating CE Efficiency Improvement for HSUPA TTI 2ms.

Table 61 Data to prepare before activating CE Efficiency Improvement for HSUPA TTI 2ms

Parameter Name Parameter ID Setting Notes Data source

HSUPA 2ms CE EfficiencyImprovement Switch

CEIMPROVEMENT2MSSW Set this parameter to ON(ON). Engineeringdesign

6.3.3 Activation

Using MML Commands

Run the NodeB MML command SET NODEBALGPARA with HSUPA 2ms CE Efficiency Improvement Switch set to ON(ON).

MML Command Examples

//Activating CE Efficiency Improvement for HSUPA TTI 2ms SET NODEBALGPARA: CEIMPROVEMENT2MSSW=ON;

Using the CME

NOTE:When configuring the feature on the CME, perform a single configuration first, and then perform a batch modification if required.

Configure the parameters of a single object before a batch modification. Perform a batch modification before logging out of theparameter setting interface.

1. Configure a single object (such as a cell) on the CME.Set parameters on the CME according to the operation sequence in Table 62. For instructions on how to perform theCME single configuration, see CME Single Configuration Operation Guide.

2. (Optional) Modify objects in batches on the CME. (CME batch modification center)

To modify objects in batches, click on the CME to start the batch modification wizard. For instructions on how toperform a batch modification through the CME batch modification center, press F1 on the wizard interface to obtain onlinehelp.

Table 62 Configuring parameters on the CME

SN MO NE Parameter Name Parameter ID Configurable inCME BatchModification Center

1 NODEBALGPARA NodeB HSUPA 2ms CEEfficiency ImprovementSwitch

CEIMPROVEMENT2MSSW Yes

6.3.4 Activation ObservationCheck the value of the NodeB counter VS.HSUPA.AlltoSingleHARQNum.CECong, which indicates the number of times an HSUPA UEwith a 2 ms TTI stops using all eight HARQ processes and starts to use a single HARQ process to transmit data due to insufficient CEresources. If the counter value is not 0, CE Efficiency Improvement for HSUPA TTI 2ms has been activated.You can also run the DSP LOCELL command to check whether the feature has been enabled.

6.3.5 Deactivation

Using MML Commands

Run the NodeB MML command SET NODEBALGPARA with HSUPA 2ms CE Efficiency Improvement Switch set to OFF(OFF).

MML Command Examples

//Deactivating CE Efficiency Improvement for HSUPA TTI 2ms SET NODEBALGPARA: CEIMPROVEMENT2MSSW=OFF;

Using the CME

NOTE:When configuring the feature on the CME, perform a single configuration first, and then perform a batch modification if required.Configure the parameters of a single object before a batch modification. Perform a batch modification before logging out of theparameter setting interface.

1. Configure a single object (such as a cell) on the CME.

Set parameters on the CME according to the operation sequence in Table 63. For instructions on how to perform theCME single configuration, see CME Single Configuration Operation Guide.

2. (Optional) Modify objects in batches on the CME. (CME batch modification center)

To modify objects in batches, click on the CME to start the batch modification wizard. For instructions on how toperform a batch modification through the CME batch modification center, press F1 on the wizard interface to obtain onlinehelp.

Table 63 Configuring parameters on the CME

SN MO NE Parameter Name Parameter ID Configurable in CMEBatch ModificationCenter

1 NODEBALGPARA NodeB HSUPA 2ms CEEfficiency ImprovementSwitch

CEIMPROVEMENT2MSSW Yes

6.4 Performance MonitoringWith this feature activated, admission CE consumption is expected to decrease. You can observe the counters listed in the followingtwo tables.

Counters related to consumed admission CEs within a NodeB

Counter Name Counter Description

VS.NodeB.ULCreditUsed.Mean Average NodeB Uplink Credit Usage When CE Overbooking IsEnabled for NodeB

VS.NodeB.ULCreditUsed.Max Maximum NodeB Uplink Credit Usage When CE Overbooking IsEnabled for NodeB

Counters related to CE resource usage of a local cell group (LCG)


VS.LCG.ULCreditUsage.Mean Average Uplink Credit Usage of LCG for Cell

VS.LCG.ULCreditUsage.Max Maximum Uplink Credit Usage of LCG for Cell

With this feature activated, the number of UEs in the CELL_DCH state, HSUPA UEs, and UEs with a 2 ms TTI is expected toincrease. You can observe the counters listed in the following table.

Counter related to the number of UEs in the CELL_DCH state, HSUPA UEs, and UEs with a 2 ms TTI


VS.CellDCHUEs Number of UEs in CELL_DCH State for Cell

VS.HSUPA.UE.Max.cell Maximum Number of HSUPA UEs in a Cell

VS.HSUPA.UE.Mean.cell Average Number of HSUPA UEs in a Cell

VS.HSUPA.UE.Max.TTI2ms Maximum Number of HSUPA 2 ms TTI UEs in a Cell

VS.HSUPA.UE.Mean.TTI2ms Average Number of HSUPA 2 ms TTI UEs in a Cell

With this feature activated, the number of failed RRC/RAB setup attempts and the number of times TTI switching and LDR are triggereddue to insufficient CE resources are expected to decrease. You can observe the counters listed in the following three tables.

Counters related to the number of failed RRC/RAB setup attempts caused by insufficient uplink CE resources


VS.RRC.Rej.ULCE.Cong Number of RRC Connection Rejects for Cell (UL CEResource Congestion)

VS.RAB.FailEstabCS.ULCE.Cong Number of Failed CS RAB Establishments for Cell (UL CE

Congestion)

VS.RAB.FailEstabPS.ULCE.Cong Number of Failed PS RAB Establishments for Cell (UL CECongestion)

VS.HSUPA.RAB.FailEstab.ULCE.Cong Number of Failed HSUPA Service Establishments Due toUL CE Insufficiency for Cell

Counters related to the number of times TTI switching is triggered due to insufficient CE resources


VS.HSUPA.TTI2to10.ADMCE.Succ Number of Successful TTI Switchovers Based on AdmittedCEs During RB Reconfiguration in a Cell(2ms to 10ms)

VS.HSUPA.RABEstabTTI10ms.AdmCE.Succ Number of Successful RAB Establishments Initiated byHSUPA 2 ms UEs with a 10 ms TTI Due to Congestion ofAdmitted CEs in a Cell

Counter related to the number of times LDR is triggered due to insufficient CE resources


VS.LCC.LDR.Num.ULCE Number of Times a Cell Is in LDR State Due to UL CEResource Congestion for Cell

With this feature activated, the number of times HSUPA UEs experience service drops due to insufficient CE resources is expected todecrease. However, the number of times HSUPA UEs experience service drops due to poor coverage will increase because 2 ms TTIprovides weaker coverage than 10 ms TTI. You can observe the counters listed in the following table.

Counters related to HSUPA service drops


VS.HSUPA.RAB.AbnormRel Number of HSUPA RABs Abnormal Releases for Cell

VS.HSUPA.RAB.AbnormRel.E2P Number of RABs Abnormally Released for PS HSUPA Servicesduring the State Transition from CELL_DCH to CELL_PCH orURA_PCH for Cell

VS.HSUPA.RAB.NormRel Number of HSUPA RABs Normal Released for Cell

VS.HSUPA.HHO.E2D.SuccOutIntraFreq Number of Successful HSUPA IntraFrequency Hard Handoversfor Cell(EDCH to DCH)

VS.HSUPA.E2F.Succ Number of Successful Channel Conversions from EDCH toFACH for HSUPA Service for Cell

VS.HSUPA.E2D.Succ Number of Successful Channel Conversions from EDCH toDCH for HSUPA Service for Cell

VS.HSUPA.E2P.Succ Number of Successful Times That a UE Performing HSUPAServices Transits to CELL_PCH or URA_PCH State for cell

With this feature activated, network load may raise due to the increased number of UEs with a 2 ms TTI. You can observe the counterslisted in the following two tables.

Counter related to the cell average RTWP


VS.MeanRTWP Mean Power of Totally Received Bandwidth for Cell

Counters related to air interface load of a cell (NodeB)


VS.HSUPA.LoadOutput.0 throughVS.HSUPA.LoadOutput.25

Number of Cell Ul Load Between 0db to 0.5dbthrough Number of Cell Ul Load above 30db

With this feature activated, uplink HSUPA throughput in the case of insufficient CE resources may increase. However, if cell load isheavy, uplink HSUPA throughput may decrease because 2 ms TTI results in more loads than 10 ms TTI. You can observe the counterslisted in the following table.

Counters related to average HSUPA throughput within in a cell (NodeB)


VS.HSUPA.MeanBitRate Average throughput of HSUPA users in a cell

VS.HSUPA.MeanBitRate.WithData Average throughput of HSUPA users in a cell when datais transmitted

With this feature activated, you can check CE consumption and number of HSUPA UEs with a 2 ms TTI transmitting data at a low rateby observing the counters listed in the following two tables.

Counters related to CE consumption on the NodeB (NodeB)


VS.ULCE.Mean.Shared Average Shared Uplink CE

VS.LC.ULMean.LicenseGroup.Shared Average number of UL CEs consumed in a shared group

VS.CE.ULMean.UlGroup Mean Number of Uplink CEs Consumed by All Cells in an UplinkResource Group

Counter related to the number of HSUPA UEs with a 2 ms TTI transmitting data at a low rate


VS.HSUPA.LowRateTTI2msUserNumber Average number of 2 ms TTI HSUPA users at a rate lower thanor equal to 23.25 kbit/s in a cell

After this feature is activated, you can check the number of times an HSUPA UE with a 2 ms TTI stops using all the eight HARQprocesses and begins to use a single HARQ process to transmit data due to insufficient CE resources and vice versa by observing thecounters listed in the following table.

Counters related to the number of times an HSUPA UE with a 2 ms TTI stops using all the eight HARQ processes andstarts to use a single HARQ process to transmit data due to insufficient CE resources and vice versa (NodeB)


VS.HSUPA.AlltoSingleHARQNum.CECong Number of transitions from using all HARQ processes tousing a single HARQ process due to limited CEs in the cell

VS.HSUPA.SingletoAllHARQNum Number of Transitions from Using A Single HARQ Processto Using All HARQ Processes In the Cell

Number of failed RRC/RAB setup attempts caused by insufficient downlink CE resources


VS.RRC.Rej.DLCE.Cong Number of RRC Connection Rejects for Cell (DL CEResource Congestion)

VS.RAB.FailEstabCS.DLCE.Cong Number of Failed CS RAB Establishments for Cell (DL CECongestion)

VS.RAB.FailEstabPS.DLCE.Cong Number of Failed PS RAB Establishments for Cell (DL CECongestion)

6.5 Parameter OptimizationWith this feature activated, if the number of times service drops occur due to poor coverage increases, you are advised to enablecoveragebased dynamic TTI adjustment. For detailed operations, see HSUPA TTI Selection Feature Parameter Description.

As the airinterface efficiency of UEs with a 2 ms TTI is lower than that of UEs with a 10 ms TTI, cell load may increase after thisfeature is activated. As a result, congestion increases in heavily loaded cells, leading to reduced uplink throughput, rejected uplinkpower admissions, or call drops. To combat this effect, you are advised to enable Turbo IC Phase2. For detailed operations, seeHSUPA Data Channel Interference Cancellation Feature Parameter Description. You can also enable TTI switching based on the

RTWP to switch UEs from the 2 ms TTI or the 10 ms TTI when the uplink load is heavy.

When this feature is enabled, if the consumed CE resources accounts for 60% of all configured CE resources for the NodeB and thereare more than 10 HSUPA UEs with a 2 ms TTI requiring a low data rate (indicated by the VS.HSUPA.LowRateTTI2msUserNumbercounter), you can enable such UEs to use an initial single HARQ process to save CE resources. However, this will prolong servicedelay. Therefore, you are not advised to do so unless the actual CE usage still exceeds 60% of the congestion threshold after thefeature is activated.Once this feature is activated, if the number of denied access attempts caused by insufficient downlink CE resources increases, runthe NodeB MML command SET NODEBRESALLOCRULE with Resource Allocate Rule set to CAPAFIRST(Capacity First Rule).

6.6 TroubleshootingNone

7 Parameters

Table 71 Parameter description

Parameter ID NE MML Command Feature ID Feature Name Description

CEIMPROVEMENT2MSSW BTS3900,BTS3900WCDMA

SETNODEBALGPARALSTNODEBALGPARA

WRFD160205

CE EfficiencyImprovement forHSUPA TTI 2ms

Meaning: Indicatesthe switch for CEefficiencyimprovement for 2ms TTI HSUPAusers.GUI Value Range:OFF(OFF),ON(ON)Unit: NoneActual ValueRange: OFF, ONDefault Value:OFF(OFF)

INITSINGLEHARQSW BTS3900,BTS3900WCDMA

SETNODEBALGPARALSTNODEBALGPARA

WRFD160205

CE EfficiencyImprovement forHSUPA TTI 2ms

Meaning: Indicatesthe switch for initialactivation of singleHARQ for 2 msTTI HSUPA users.If this switch isturned on, singleHARQ takes effecton newly admittedusers.GUI Value Range:OFF(OFF),ON(ON)Unit: NoneActual ValueRange: OFF, ONDefault Value:OFF(OFF)

SrbChlTypeRrcEffectFlag BSC6900 SETUFRCCHLTYPEPARA

WRFD010510WRFD01061112WRFD150232WRFD010652

3.4/6.8/13.6/27.2KbpsRRC Connection andRadio Access BearerEstablishment andReleaseHSDPA DRDMultiband DirectRetry Based on UELocation

Meaning: Whetherthe configured typeof channel thatpreferably carriesthe signaling RB iseffective in thecase of RRCconnectionestablishment.GUI Value Range:

SRB over HSDPA FALSE, TRUEUnit: NoneActual ValueRange: TRUE,FALSEDefault Value:False

SrbChlTypeRrcEffectFlag BSC6910 SETUFRCCHLTYPEPARA

WRFD010510WRFD01061112WRFD150232WRFD010652

3.4/6.8/13.6/27.2KbpsRRC Connection andRadio Access BearerEstablishment andReleaseHSDPA DRDMultiband DirectRetry Based on UELocationSRB over HSDPA

Meaning: Whetherthe configured typeof channel thatpreferably carriesthe signaling RB iseffective in thecase of RRCconnectionestablishment.GUI Value Range:FALSE, TRUEUnit: NoneActual ValueRange: TRUE,FALSEDefault Value:False

8 Counters

Table 81 Counter description

Counter ID Counter Name CounterDescription

NE Feature ID Feature Name

50331958 VS.HSUPA.AlltoSingleHARQNum.CECong Number oftransitionsfrom using allHARQprocesses tousing a singleHARQprocess dueto limited CEsin the cell

NodeB Multimode:NoneGSM: NoneUMTS:WRFD160205LTE: None


50331959 VS.HSUPA.SingletoAllHARQNum Number ofTransitionsfrom Using ASingle HARQProcess toUsing AllHARQProcesses Inthe Cell

NodeB Multimode:NoneGSM: NoneUMTS:WRFD160213WRFD160205LTE: None

Turbo IC Phase2CE EfficiencyImprovementfor HSUPA TTI2ms

50341892 VS.HSUPA.LowRateTTI2msUserNumber Averagenumber of 2ms TTIHSUPA usersat a rate lowerthan or equalto 23.25 kbit/s

NodeB Multimode:NoneGSM: NoneUMTS:WRFD160205


in a cell LTE: None

9 Glossary

For the acronyms, abbreviations, terms, and definitions, see Glossary.

10 Reference Documents

1. 3GPP TS 25.211, " Physical channels and mapping of transport channels onto physical channels (FDD)"

2. 3GPP TS 25.321, " Medium Access Control (MAC) protocol specification"

3. CE Resource Management Feature Parameter Description

4. CE Overbooking Feature Parameter Description

5. HSUPA Feature Parameter Description

6. HSUPA TTI Selection Feature Parameter Description

7. HSUPA Data Channel Interference Cancellation Feature Parameter Description

8. License Management Feature Parameter Description

CE Efficiency Improvement for HSUPA TTI 2ms

Documents

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