eRAN
Uplink Timing Control Feature Parameter Description Issue
02
Date
2015-11-03
HUAWEI TECHNOLOGIES CO., LTD.
Copyright © Huawei Technologies Co., Ltd. 2015. 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 Huawei Technologies 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.
Notice The purchased products, services and features are stipulated by the contract made between Huawei and the customer. All or part of the products, services and features described in this document may not be within the purchase scope or the usage scope. Unless otherwise specified 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 to ensure accuracy of the contents, but all statements, information, and recommendations in this document do not constitute a warranty of any kind, express or implied.
Huawei Technologies Co., Ltd. Address:
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Website:
http://www.huawei.com
Email:
[email protected]
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Contents
Contents 1 About The Document................................................................................................................... 1 1.1 Scope.............................................................................................................................................................................. 1 1.2 Intended Audience.......................................................................................................................................................... 1 1.3 Change History............................................................................................................................................................... 1 1.4 Differences Between eNodeB Types.............................................................................................................................. 2
2 Overview......................................................................................................................................... 3 2.1 Introduction.................................................................................................................................................................... 3 2.2 Benefits........................................................................................................................................................................... 3
3 Technical Description...................................................................................................................4 3.1 Uplink Timing Control During RA................................................................................................................................ 6 3.2 Uplink Timing Control After RA................................................................................................................................... 7 3.3 Timers............................................................................................................................................................................. 9 3.3.1 Uplink Time Alignment Timer.................................................................................................................................... 9 3.3.2 Uplink Synchronization Timer.................................................................................................................................. 12 3.3.3 UE Inactivity Timer................................................................................................................................................... 12
4 Related Features...........................................................................................................................14 4.1 LBFD-070101 Uplink Timing Based on PUCCH........................................................................................................14
5 Network Impact........................................................................................................................... 16 5.1 LBFD-070101 Uplink Timing Based on PUCCH........................................................................................................16
6 Engineering Guidelines............................................................................................................. 17 6.1 When to Use LAOFD-001001 and LAOFD-001002................................................................................................... 17 6.2 Required Information................................................................................................................................................... 17 6.3 Planning........................................................................................................................................................................ 17 6.4 Deployment.................................................................................................................................................................. 17 6.4.1 Requirements............................................................................................................................................................. 17 6.4.2 Data Preparation........................................................................................................................................................ 18 6.4.3 Initial Configuration.................................................................................................................................................. 20 6.4.4 Activation Observation..............................................................................................................................................23 6.4.5 Deactivation...............................................................................................................................................................23 6.4.6 Reconfiguration......................................................................................................................................................... 26 6.5 Performance Monitoring...............................................................................................................................................26 Issue 02 (2015-11-03)
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Contents
6.6 Parameter Optimization................................................................................................................................................ 27 6.7 Troubleshooting............................................................................................................................................................ 28
7 Parameters..................................................................................................................................... 29 8 Counters........................................................................................................................................ 35 9 Glossary......................................................................................................................................... 37 10 Reference Documents............................................................................................................... 38
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1 About The Document
1
About The Document
1.1 Scope This document describes LBFD-070101 Uplink Timing Based on PUCCH and uplink timing control, including their technical principles, related features, network impact, and engineering guidelines. Any managed objects (MOs), parameters, alarms, or counters described herein correspond to the software release delivered with this document. Any future updates will be described in the product documentation delivered with future software releases. This document applies only to LTE FDD. Any "LTE" in this document refers to LTE FDD, and "eNodeB" refers to LTE FDD eNodeB. This document applies to the following types of eNodeBs. eNodeB Type
Model
Macro
3900 series eNodeB
Micro
BTS3202E
LampSite
DBS3900 LampSite
1.2 Intended Audience This document is intended for personnel who: l
Need to understand the features described herein
l
Work with Huawei products
1.3 Change History This section provides information about the changes in different document versions. There are two types of changes: Issue 02 (2015-11-03)
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l
1 About The Document
Feature change
Changes in features and parameters of a specified version as well as the affected entities l
Editorial change
Changes in wording or addition of information and any related parameters affected by editorial changes. Editorial change does not specify the affected entities.
eRAN8.1 02 (2015-11-03) This issue includes the following changes. Change Type
Change Description
Parameter Change
Affected Entity
Feature change
None
None
N/A
Editorial change
Added the actual TA command sending period when the TimeAlignmentTimer.TACmdSendPeriod parameter is set to. INVALID. For details, see 4 in 3.2 Uplink Timing Control After RA.
None
-
Revised descriptions in the document.
None
-
eRAN8.1 01 (2015-03-23) This issue does not include any changes.
eRAN8.1 Draft A (2015-01-15) Compared with Issue 04 (2014-09-30) of eRAN7.0, Draft A (2015-01-15) of eRAN8.1 does not include any changes.
1.4 Differences Between eNodeB Types The features described in this document are implemented in the same way on macro, micro, and LampSite eNodeBs.
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eRAN Uplink Timing Control Feature Parameter Description
2 Overview
2
Overview
2.1 Introduction During uplink timing control, the eNodeB calculates the timing offset after measuring uplink signals received from a UE. Based on the results of this calculation, the eNodeB then converts the timing offset into the Timing Advance Command and sends the command to the UE. The UE uses this information to adjust the time to transmit uplink signals. The entire process ensures time synchronization between the UE and the eNodeB, as shown in Figure 2-1. Figure 2-1 Uplink timing control
2.2 Benefits With uplink timing control, the eNodeB adjusts the time of each UE to transmit uplink signals so that uplink signals from different UEs simultaneously reach the eNodeB. This ensures orthogonality of data transmitted from different UEs, mitigates intra-cell interference, and ensures demodulation performance on data transmitted by UEs.
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3 Technical Description
3
Technical Description
Uplink timing control can be categorized into uplink timing control during random access (RA) and uplink timing control after RA, as shown in Figure 3-1. l
Uplink timing control during RA Non-synchronized UEs (including UEs that are newly powered on or handed over to the cell, UEs in RRC_IDLE mode, and out-of-synchronized UEs) establish or restore uplink synchronization based on RA, and then enter the synchronization state. For details, see 3.1 Uplink Timing Control During RA.
l
Uplink timing control after RA A synchronized UE maintains the synchronization state based on periodic uplink timing adjustment. For details, see 3.2 Uplink Timing Control After RA. When a UE is in the synchronization state, timers, including the uplink time alignment timer, uplink synchronization timer, and UE inactivity timer, maintain and manage the synchronization state of the UE. For details about working principles and settings of these timers, see 3.3.1 Uplink Time Alignment Timer, 3.3.2 Uplink Synchronization Timer, and 3.3.3 UE Inactivity Timer. –
If the uplink time alignment timer expires, an uplink-synchronized UE enters the out-of-synchronization state.
–
If the uplink synchronization timer expires, this causes the uplink time alignment timer to expire, and then an uplink-synchronized UE enters the out-ofsynchronization state.
–
If the UE inactivity timer expires, an uplink-synchronized UE enters the RRC_IDLE mode.
A non-synchronized UE enters the synchronization state by initiating the RA procedure.
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Figure 3-1 Timers maintaining the UE state
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3 Technical Description
3.1 Uplink Timing Control During RA RA is classified into contention-based RA and non-contention-based RA. A UE achieves uplink synchronization with the eNodeB based on uplink timing during RA. Figure 3-2 outlines the procedure for uplink timing control during RA. Figure 3-2 Uplink timing control during RA
1.
A UE sends a Random Access Preamble message to the eNodeB.
2.
The eNodeB measures the timing offset on the UE side based on the received Random Access Preamble message.
3.
The eNodeB converts the measured timing offset into a Timing Advance Command.
4.
The eNodeB sends the UE the Timing Advance Command, which is contained in the Random Access Response message.
5.
Upon receiving the Timing Advance Command, the UE adjusts the time to transmit uplink signals. For details about timing adjustment, see section 4.2.3 "Transmission timing adjustments" in 3GPP TS 36.213 V10.10.0.
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3.2 Uplink Timing Control After RA After RA is performed, an uplink-synchronized UE maintains uplink synchronization with the eNodeB based on periodic uplink timing adjustment. Figure 3-3 shows the procedure for periodic uplink timing adjustment. Figure 3-3 Periodic uplink timing adjustment
1.
The eNodeB allocates uplink resources to a UE, and the UE transmits uplink signals. Resources allocated to the UE may include sounding reference signal (SRS) resources, demodulation reference signal (DMRS) for the physical uplink shared channel (PUSCH), or channel quality indicator (CQI) in physical uplink control channel (PUCCH).
2.
The eNodeB receives the transmitted uplink signals and measures the timing offset of the UE. The timing offset can be measured based on the allocated SRS resources, DMRS for PUSCH, or CQI in PUCCH. The TimeAlignmentTimer.TimingMeasMode parameter specifies the method for measuring uplink timing offsets. –
–
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When this parameter is set to INVALID(Invalid Timing Measurement Mode): n
If the eNodeB has already allocated SRS resources to a UE, the eNodeB measures the timing offset of the UE based on the SRS resources.
n
If the eNodeB has not allocated SRS resources to a UE, the eNodeB measures the timing offset of the UE based on the DMRS for PUSCH. If the UE does not have any PUSCH resources, the eNodeB allocates PUSCH resources to the UE and then measures the timing offset based on the DMRS for PUSCH.
When this parameter is set to ALLMEASMODE(All Timing Measurement Mode): Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
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n
If the eNodeB has already allocated SRS resources to a UE, the eNodeB measures the timing offset of the UE based on the SRS resources. If the UE has PUSCH resources, the eNodeB measures the timing offset of the UE based on the SRS and DMRS for PUSCH, where the timing offset measured based on the DMRS for PUSCH is preferentially used.
n
If the eNodeB has not allocated SRS resources to a UE, the eNodeB measures the timing offset of the UE based on the CQI in PUCCH. If the UE has PUSCH resources, the eNodeB measures the timing offset of the UE based on the CQI in PUCCH and DMRS for PUSCH, where the timing offset measured based on the DMRS for PUSCH is preferentially used. NOTE
The eNodeB measures the timing offset of the UE based on the CQI in PUCCH only when the eNodeB has allocated periodic CQIs to the UE. The eNodeB allocates periodic CQIs to UEs that are newly powered on, UEs that are newly handed over to the cell, and UEs in idle mode. The eNodeB reconfigures periodic CQIs for asynchronized UEs to restore synchronization with the eNodeB. NOTE
When the TimeAlignmentTimer.TimingResOptSwitch parameter is set to ON(On), the amount of DMRS for PUSCH allocated by the eNodeB to UEs for timing offset measurements decreases, but the UE mobility speed supported by DMRS-based uplink timing decreases. You are advised to set this parameter to ON(On) in heavy traffic scenarios. When the TimeAlignmentTimer.TimingResOptSwitch is set to ON(On), selecting the TaEnhancePuschDmrs option of the TimeAlignmentTimer.TaEnhance parameter decreases the amount of DMRS for PUSCH allocated by the eNodeB to UEs for timing offset measurements to a larger extent.
3.
The eNodeB converts the measured timing offset into a Timing Advance Command.
4.
The eNodeB sends the UE the Timing Advance Command. The TimeAlignmentTimer.TimingAdvCmdOptSwitch parameter specifies the policy of sending Timing Advance Commands to UEs. –
If the TimeAlignmentTimer.TimingAdvCmdOptSwitch parameter is set to OFF(Off), the eNodeB periodically sends the Timing Advance Command to the UE. This is called the periodic policy. The length of Timing Advance Command sending period is calculated by the formula "Floor (the TimeAlignmentTimer.TimeAlignmentTimer parameter value/2 - 32)" and cannot be manually set.
–
If the TimeAlignmentTimer.TimingAdvCmdOptSwitch parameter is set to ON(On), the eNodeB adopts the periodic evaluation and event-triggering policy. The period can be set by the TimeAlignmentTimer.TACmdSendPeriod parameter. A smaller value of this parameter indicates that the eNodeB sends the Timing Advance Commands to UEs more frequently. As a result, more air interface resources are consumed and a higher mobility speed can be supported. A larger value of this parameter results in the opposite effects. If this parameter is set to INVALID(NULL), the period that the eNodeB adopts to send Timing Advance Commands takes the smaller value between 928 ms and the value calculated by the formula "Value of TimeAlignmentTimer.TimeAlignmentTimer/2 - 32 ms". In the periodic evaluation and event-triggering policy, the eNodeB periodically determines whether a UE experiences timing offsets. n
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If timing offsets occurred on the UE within the Timing Advance Command sending period, the eNodeB sends a Timing Advance Command to the UE.
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3 Technical Description
If timing offsets did not occur on the UE within the Timing Advance Command sending period, the eNodeB does not send a Timing Advance Command to the UE. NOTE
If the UE does not experience a timing offset before the uplink time alignment timer expires, the eNodeB sends the Timing Advance Command to the UE in case that the uplink time alignment timer expires because the UE does not receive the Timing Advance Command for a long time. NOTE
If the TimeAlignmentTimer.TimingMeasMode parameter is set to ALLMEASMODE(All Timing Measurement Mode) or the TimeAlignmentTimer.TimingResOptSwitch parameter is set to ON(On), the eNodeB always adopts the periodic evaluation and event-triggering policy regardless of the TimeAlignmentTimer.TimingAdvCmdOptSwitch parameter setting.
5.
Upon receiving the Timing Advance Command, the UE adjusts the time to transmit uplink signals to maintain uplink synchronization with the eNodeB. For details about timing adjustment, see section 4.2.3 "Transmission timing adjustments" in 3GPP TS 36.213 V10.10.0.
6.
Uplink timing offset measurements and uplink timing adjustments are performed periodically based on steps 1 to 5.
3.3 Timers 3.3.1 Uplink Time Alignment Timer Timer Working Principles Uplink synchronization between a UE and the eNodeB is performed using their respective time alignment timers. l
The UE uses its uplink time alignment timer to determine whether it is in the synchronization state. Before the timer expires, the UE considers itself is in the synchronization state. After the timer expires, the UE considers itself is in the out-ofsynchronization state.
l
The eNodeB uses its uplink timer alignment timer to determine whether the UE is in the synchronization state. Before the timer expires, the eNodeB determines that the UE is in the synchronization state. After the timer expires, the eNodeB determines that the UE is in the out-of-synchronization state and stops sending the Timing Advance Command to the UE, excluding the Timing Advance Command included in the Random Access Response message.
Table 3-1 describes the working principles of the uplink time alignment timers on the UE side and the eNodeB side.
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Table 3-1 Working principles of uplink time alignment timers Timer
Action
Description
Uplink time alignment timer on the UE side
Start
l In the scenario where the UE receives the Timing Advance Command included in the Random Access Response message during RA: – During a non-contention-based RA, the UE starts or restarts the timer. – During a contention-based RA, if the timer has not started, the UE starts the timer. If the timer has started, the UE does not restart the timer. l Upon receiving the Timing Advance Command after RA, the UE starts or restarts the timer. NOTE During contention-based RA, the timer stops if the contention-based RA fails.
Expire
l If the UE does not receive the Timing Advance Command from the eNodeB, the UE does not restart the timer. As a result, the timer will expire. l After the uplink synchronization timer for the UE expires, the eNodeB no longer sends the Timing Advance Command to the UE, and therefore the UE does not restart the timer. As a result, the timer will expire.
Uplink time alignment timer on the eNodeB side
Start
l During RA: – During a non-contention-based RA, the eNodeB starts or restarts the timers after receiving an ACK from the UE that replies to the delivered Random Access Response message. – During a contention-based RA, the eNodeB starts or restarts the timer for the UE that has successfully accessed the network. l If the UE has successfully accessed the network, the eNodeB starts or restarts the timer after receiving the ACK from the UE that replies to the delivered Timing Advance Command.
Expire
l If the eNodeB does not receive an ACK from the UE after delivering the Timing Advance Command, the eNodeB does not restart the timer. As a result, the timer will expire. l After the uplink synchronization timer for the UE expires, the eNodeB no longer sends the Timing Advance Command to the UE, and therefore the eNodeB does not restart the timer. As a result, the timer will expire.
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Both the uplink time alignment timer on the UE side and that on the eNodeB side can be restarted during the running process to prolong the duration of uplink synchronization. Upon receiving the Timing Advance Command from the eNodeB, the UE restarts its uplink time alignment timer and sends an ACK to the eNodeB. Upon receiving the ACK, the eNodeB restarts its uplink time alignment timer, as shown in Figure 3-4. Figure 3-4 Time to restart the uplink time alignment timers
Timer Settings The uplink time alignment timer on the UE side and the timer on the eNodeB side are controlled separately. The TimeAlignmentTimer.TimeAlignmentTimer parameter specifies the uplink time alignment timer length on the eNodeB side. After setting the timer value, the value is sent to the UE through air interface signaling. l
If the eNodeB adopts the periodic policy, it is recommended that the TimeAlignmentTimer.TimeAlignmentTimer parameter be set to SF1920(1920 subframes). When the TimeAlignmentTimer.TimeAlignmentTimer parameter is set to a smaller value, the eNodeB sends the Timing Advance Command to the UE at a higher frequency, more radio resources are consumed, and higher mobility speed can be supported. If the TimeAlignmentTimer.TimeAlignmentTimer parameter is set to a larger value, the opposite effect is generated.
l
If the eNodeB adopts the periodic evaluation and event-triggering policy, it is recommended that the TimeAlignmentTimer.TimeAlignmentTimer parameter be set to SF10240(10240 subframes). In heavy traffic scenarios where the TimeAlignmentTimer.TimingResOptSwitch parameter is set to ON(On), you are advised to set the TimeAlignmentTimer.TimeAlignmentTimer parameter to INFINITY(Infinity). A smaller value of the TimeAlignmentTimer.TimeAlignmentTimer parameter (for example, less than SF5120(5120 subframes)) leads to a higher probability of UEs in the discontinuous reception (DRX) state entering the out-of-synchronization state. NOTE
For details about the relationship between the TimeAlignmentTimer.TimeAlignmentTimer parameter value and the DRX state, see DRX and Signaling Control Feature Parameter Description.
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3.3.2 Uplink Synchronization Timer Timer Working Principles The uplink synchronization timer controls whether the eNodeB continues to maintain uplink synchronization between a UE and the eNodeB. The eNodeB maintains an uplink synchronization timer for each UE. Table 3-2 Working principles of the uplink synchronization timer Action
Description
Start
The eNodeB starts or restarts the timer for a UE while sending data to or receiving data from the UE. Before the uplink synchronization timer for a UE expires, the eNodeB continuously sends the Timing Advance Commands to the UE.
Expire
After the uplink synchronization timer for a UE expires, the eNodeB no longer sends the Timing Advance Commands to the UE, and determines that the UE enters the out-of-synchronization state after the uplink time alignment timer on the eNodeB side expires.
Timer Settings The RrcConnStateTimer.UlSynTimer parameter specifies the uplink synchronization timer length. l
A smaller value for this parameter leads to a higher probability of the UE entering the out-of-synchronization state, a shorter time for the UE to occupy PUCCH and SRS resources, and a larger number of RA requests initiated by the UE.
l
A larger value for this parameter leads to a lower probability of the UE entering the outof-synchronization state, a longer time for the UE to occupy PUCCH and SRS resources, and a smaller number of RA requests initiated by the UE. NOTE
The RrcConnStateTimer.UlSynTimer parameter can be set only on the eNodeB side. If the RrcConnStateTimer.UlSynTimer parameter is set to 0, the uplink synchronization timer will never expire.
3.3.3 UE Inactivity Timer Timer Working Principles The eNodeB determines whether a UE is in RRC_CONNECTED mode based on the state of the UE inactivity timer. Table 3-3 describes the working principles of this timer.
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Table 3-3 Working principles of the UE inactivity timer Action
Description
Start
The eNodeB starts or restarts the timer for a UE while sending data to or receiving data from the UE. Before the UE inactivity timer expires, the eNodeB determines that the UE is in RRC_CONNECTED mode.
Expire
After the UE inactivity timer expires, the eNodeB sends an RRC Connection Release message to the UE; the UE is then released and enters RRC_IDLE mode. This prevents an inactive UE from occupying radio resources when it is unnecessary.
NOTE
If the UE inactivity timer for an out-of-synchronized UE expires, the UE enters the synchronization state first. Then, the eNodeB sends an RRC Connection Release message to the UE, and the UE enters the idle mode.
Timer Settings The RrcConnStateTimer.UeInactiveTimer parameter specifies the length of the UE inactivity timer. In the scenario where a UE does not send data to or receive data from the eNodeB: l
If this parameter is set to a smaller value, the UE will be released earlier, and the UE sends the RRC connection setup requests to the eNodeB at a higher frequency. Because the number of UEs released normally increases, the service drop rate decreases.
l
If this parameter is set to a larger value, the time required to release the UE will be longer, the RRC connection between the UE and the eNodeB maintains for a longer time, and the UE occupies radio resources for a longer time as well. Because the number of UEs being released normally decreases, the service drop rate increases.
l
If the value of RrcConnStateTimer.UlSynTimer is greater than the value of RrcConnStateTimer.UeInactiveTimer, the UE enters the idle mode directly. NOTE
The RrcConnStateTimer.UeInactiveTimer parameter can be set only on the eNodeB side. If the parameter setting is changed, the change applies to UEs that newly access the network. If the RrcConnStateTimer.UeInactiveTimer parameter is set to 0, the timer does not take effect, which means the UEs are always in connected mode.
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4 Related Features
4
Related Features
4.1 LBFD-070101 Uplink Timing Based on PUCCH Prerequisite Features None
Mutually Exclusive Features None
Impacted Features l
LOFD-001008 Ultra High Speed Mobility LOFD-001008 Ultra High Speed Mobility takes priority over LBFD-070101 Uplink Timing Based on PUCCH. If the Cell.HighSpeedFlag parameter is set to ULTRA_HIGH_SPEED(Ultra high speed cell flag) or EXTRA_HIGH_SPEED(Extra high speed cell flag), LBFD-070101 Uplink Timing Based on PUCCH does not take effect.
l
LOFD-001031 Extended CP LOFD-001031 Extended CP takes priority over LBFD-070101 Uplink Timing Based on PUCCH. If the Cell.UlCyclicPrefix parameter is set to EXTENDED_CP(Extended), LBFD-070101 Uplink Timing Based on PUCCH does not take effect.
l
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LBFD-002017 DRX –
When LBFD-002017 DRX is enabled, parameters related to DRX are restrained by uplink timing. For details, see DRX and Signaling Control Feature Parameter Description. When both LBFD-002017 DRX and LBFD-070101 Uplink Timing Based on PUCCH are enabled, parameters related to DRX are no longer restrained by uplink timing, and therefore the power consumption of UEs in the DRX state can be further reduced.
–
If DRX is enabled, the eNodeB receives CQIs in PUCCH from UEs only when the UEs are in the DRX active time. The timing offset measurement accuracy depends on the number of CQIs in PUCCH received by the eNodeB. In scenarios where the long DRX cycle duration is greater than or equal to 160 ms, to ensure that the eNodeB can measure accurate timing offset before delivering the Timing Advance Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.
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Command, the Timing Advance Command sending period must be extended to enable the eNodeB to obtain sufficient CQIs in PUCCH. However, extending the Timing Advance Command sending period decreases the supported mobility speed of the UE. –
l
If the eNodeB does not receive a valid periodic CQI report within eight consecutive periodic CQI reporting periods from a UE in DRX sleep time, the eNodeB instructs the UE to send an aperiodic CQI report in the DRX active time. The aperiodic CQI report must be sent based on CQI_ONLY scheduling if the UE does not have uplink data to transmit. CQI_ONLY scheduling consumes air interface resources and reduces gains generated by LBFD-070101 Uplink Timing Based on PUCCH.
LOFD-00110501 Dynamic DRX The impact of LBFD-070101 Uplink Timing Based on PUCCH on LOFD-00110501 Dynamic DRX is the same as that on LBFD-002017 DRX.
l
LOFD-00101502 Dynamic Scheduling When preallocation or intelligent preallocation is enabled, the eNodeB actively initiates uplink scheduling for UEs that are not allocated SRS resources. In this situation, the eNodeB measures the timing offset of the UE based on the DMRS for PUSCH. If you enable LBFD-070101 Uplink Timing Based on PUCCH in this scenario, the eNodeB measures the timing offset of the UE based on both the DMRS for PUSCH and CQI in PUCCH. However, uplink timing adjustment is performed based on the timing offset calculated based on the DMRS for PUSCH. NOTE
Micro eNodeBs do not support LOFD-001008 Ultra High Speed Mobility and LOFD-001031 Extended CP. Therefore, the impacts of these features on LBFD-070101 Uplink Timing Based on PUCCH do not apply to micro eNodeBs.
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5 Network Impact
5
Network Impact
5.1 LBFD-070101 Uplink Timing Based on PUCCH System Capacity In LBFD-070101 Uplink Timing Based on PUCCH, when the eNodeB adopts the periodic evaluation and event-triggering policy, fewer control channel elements (CCEs) in the PDCCH are consumed for measuring uplink timing offset based on DMRS for PUSCH, and therefore the PDCCH can support more UEs. The number of reduced CCEs varies according to site requirements and cannot be quantified. This is because the number depends on the number of users in a network, user distribution, and service type.
Network Performance In LBFD-070101 Uplink Timing Based on PUCCH, when the eNodeB adopts the periodic evaluation and event-triggering policy, fewer physical resource blocks (PRBs) in the PUSCH are consumed for measuring uplink timing offset based on DMRS for PUSCH, and the usage of PRB in the PUSCH decreases. If there is a large number of UEs in the cell, both the number of service drops and the number of E-RAB setup failures may slightly increase. The change varies according to site requirements and cannot be quantified. This is because such KPIs depend on the number of users in a network, user distribution, and service type.
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6
6 Engineering Guidelines
Engineering Guidelines
6.1 When to Use LAOFD-001001 and LAOFD-001002 It is recommended that LBFD-070101 Uplink Timing Based on PUCCH be enabled when both the following conditions are met: l
The SRS resources cannot support uplink timing required by all the UEs in a cell. That is, the average number of uplink synchronized UEs is greater than the average number of UEs allocated with SRS resources (the value of the L.Traffic.User.Ulsync.Avg counter specified by the counter ID 1526728481 is greater than the value of the L.Traffic.User.SRS.Avg counter specified by the counter ID 1526728481) or no SRS resources are available in the cell (the SRSCFG.SrsCfgInd parameter is set to BOOLEAN_FALSE(False)).
l
Preallocation does not take effect, for example, when DRX is enabled.
6.2 Required Information N/A
6.3 Planning N/A
6.4 Deployment 6.4.1 Requirements Operating Environment LBFD-070101 Uplink Timing Based on PUCCH must work with the LBBPd or UBBPd.
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Transmission Networking None
License None
6.4.2 Data Preparation This section describes the data that you need to collect for setting parameters. Required data is data that you must collect for all scenarios. Collect scenario-specific data when necessary for a specific feature deployment scenario. There are three types of data sources: data sources: l
Network plan (negotiation required): parameter values planned by the operator and negotiated with the evolved packet core (EPC) or peer transmission equipment
l
Network plan (negotiation not required): parameter values planned and set by the operator
l
User-defined: parameter values set by users.
Required Data The following table describes the parameters that must be set in the TimeAlignmentTimer MO to configure uplink timing measurement mode, the switch used to optimize the uplink timing command, and the uplink time alignment timer length.
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Parameter Name
Parameter ID
Data Source
Setting Notes
TimingMeas Mode
TimeAlignmen tTimer.Timing MeasMode
Network plan (negotiation not required)
This parameter specifies the mode of measuring uplink timing offsets. When this parameter is set to INVALID (Invalid Timing Measurement Mode), the eNodeB measures the timing offset of the UE based on the SRS or the DMRS for PUSCH. When this parameter is set to ALLMEASMODE(All Timing Measurement Mode), the eNodeB measures the timing offset of the UE based on both the SRS and DMRS for PUSCH or based on both the CQI in PUCCH and DMRS for PUSCH. Set this parameter by referring to 6.1 When to Use LAOFD-001001 and LAOFD-001002.
Uplink Time Alignment Timer
TimeAlignmen tTimer.TimeAli gnmentTimer
Network plan (negotiation not required)
This parameter specifies the length of the uplink time alignment timer. The value SF10240 (10240 subframes) is recommended for this parameter.
Scenario-specific Data Scenario 1: DRX is disabled, or DRX is enabled and the long DRX cycle is less than 160 ms. In this scenario, enable LBFD-070101 Uplink Timing Based on PUCCH by referring to "Setting Notes" for parameters in Required Data. Scenario 2: DRX is enabled and the long DRX cycle is greater than or equal to 160 ms. In this scenario, the parameters listed in the following table must be configured in the TimeAlignmentTimer MO.
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Parameter Name
Parameter ID
Data Source
Setting Notes
Uplink timing advance command optimization switch
TimeAlignmen tTimer.Timing AdvCmdOptSwi tch
Network plan (negotiation not required)
If this parameter is set to ON(On), the eNodeB sends less Timing Advance Commands to motionless or low-mobility UEs to save air interface resources and reduce power consumption of UEs in DRX mode. Therefore, the parameter value ON(On) is recommended.
TA Command Sending Period
TimeAlignmen tTimer.TACmd SendPeriod
Network plan (negotiation not required)
This parameter takes effect only when the TimeAlignmentTimer.TimingAdvCmdOptSwitch parameter is set to ON(On). The parameter value SF5088(5088 subframes) is recommended.
6.4.3 Initial Configuration Using the CME to Perform Batch Configuration for Newly Deployed eNodeBs Enter the values of the parameters listed in Table 7-1 in a summary data file, which also contains other data for the new eNodeBs to be deployed. Then, import the summary data file into the Configuration Management Express (CME) for batch configuration. For detailed instructions, see "Creating eNodeBs in Batches" in the initial configuration guide for the eNodeB, which is available in the eNodeB product documentation. The summary data file may be a scenario-specific file provided by the CME or a customized file, depending on the following conditions: l
The managed objects (MOs) in the following tables are contained in a scenario-specific summary data file. In this situation, set the parameters in the MOs, and then verify and save the file.
l
Some MOs in the following tables are not contained in a scenario-specific summary data file. In this situation, customize a summary data file to include the MOs before you can set the parameters.
Scenario 1: DRX is disabled, or DRX is enabled and the long DRX cycle is less than 160 ms.
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MO
Sheet in the Summary Data File
Parameter Group
Remarks
TimeAl ignmen tTimer
User-defined sheet, TimeAlignmentTimer is recommended.
For details, see 6.4.2 Data Preparation.
None
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Scenario 2: DRX is enabled and the long DRX cycle is greater than or equal to 160 ms. MO
Sheet in the Summary Data File
Parameter Group
Remarks
TimeAl ignmen tTimer
User-defined sheet, TimeAlignmentTimer is recommended.
For details, see 6.4.2 Data Preparation.
None
Using the CME to Perform Batch Configuration for Existing eNodeBs Batch reconfiguration using the CME is the recommended method to activate a feature on existing eNodeBs. This method reconfigures all data, except neighbor relationships, for multiple eNodeBs in a single procedure. Step 1 Choose CME > Advanced > Customize Summary Data File (U2000 client mode), or choose Advanced > Customize Summary Data File (CME client mode), to customize a summary data file for batch reconfiguration. NOTE
For context-sensitive help on a current task in the client, press F1.
Step 2 Choose CME > LTE Application > Export Data > Export Base Station Bulk Configuration Data (U2000 client mode), or choose Advanced > Base Station Bulk Configuration > Export Data (CME client mode), to export the eNodeB data stored on the CME into the customized summary data file. Step 3 In the summary data file, set the parameters in the MOs and close the file. Step 4 Choose CME > LTE Application > Import Data > Import Base Station Bulk Configuration Data (U2000 client mode), or choose LTE Application > Import Data > Import Base Station Bulk Configuration Data (CME client mode), to import the summary data file into the CME. Step 5 Choose CME > Planned Area > Export Incremental Scripts (U2000 client mode), or choose Area Management > Planned Area > Export Incremental Scripts (CME client mode), to export and activate the incremental scripts. ----End
Using the CME to Perform Single Configuration On the CME, set the parameters listed in the "Data Preparation" section for a single eNodeB. The procedure is as follows: Step 1 In the planned data area, click Base Station in the upper left corner of the configuration window. Step 2 In area 1 shown in Figure 6-1, select the eNodeB to which the MOs belong.
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Figure 6-1 MO search and configuration window
Step 3 On the Search tab page in area 2, enter an MO name, for example, CELL. Step 4 In area 3, double-click the MO in the Object Name column. All parameters in this MO are displayed in area 4. Step 5 Set the parameters in area 4 or 5. Step 6 Choose CME > Planned Area > Export Incremental Scripts (U2000 client mode), or choose Area Management > Planned Area > Export Incremental Scripts (CME client mode) in the main menu of the planned area, to export and activate the incremental scripts. ----End
Using MML Commands Scenario 1: DRX is disabled, or DRX is enabled and the long DRX cycle is less than 160 ms. Step 1 Run the MOD TATIMER command to set parameters TimingMeasMode and TimeAlignmentTimer. ----End Scenario 2: DRX is enabled and the long DRX cycle is greater than or equal to 160 ms. Step 1 Run the MOD TATIMER command to configure the timing measurement mode, length of the uplink time alignment timer, uplink Timing Advance Command optimization switch, and Timing Advance Command sending period. ----End
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MML Command Examples Scenario 1: DRX is disabled, or DRX is enabled and the long DRX cycle is less than 160 ms. MOD TATIMER: LocalCellId=0, TimingMeasMode=ALLMEASMODE, TimeAlignmentTimer=SF10240;
Scenario 2: DRX is enabled and the long DRX cycle is greater than or equal to 160 ms. MOD TATIMER: LocalCellId=0, TimingMeasMode=ALLMEASMODE, TimeAlignmentTimer=SF10240, TimingAdvCmdOptSwitch=ON, TACmdSendPeriod=SF5088;
6.4.4 Activation Observation Using MML Commands Run the LST TATIMER command on the eNodeB to verify that the TimingMeasMode parameter value is ALLMEASMODE. If yes, LBFD-070101 Uplink Timing based on PUCCH has been activated by performing the following operation:
Using Performance Counters If the values of both counters listed in Table 6-1 are not zero, LBFD-070101 Uplink Timing based on PUCCH takes effects. Table 6-1 Counters related to uplink timing control Counter ID
Counter Name
Description
1526730143
L.Traffic.User.TAMeas.PUC CH.Avg
This counter specifies the average number of users whose uplink timing offsets are measured based on the PUCCH.
1526730144
L.Traffic.User.TAMeas.PUC CH.Max
This counter specifies the maximum number of users whose uplink timing offsets are measured based on the PUCCH.
6.4.5 Deactivation Using the CME to Perform Batch Configuration Batch reconfiguration using the CME is the recommended method to deactivate a feature on eNodeBs. This method reconfigures all data, except neighbor relationships, for multiple eNodeBs in a single procedure. The procedure for feature deactivation is similar to that for feature activation described in "Using the CME to Perform Batch Configuration for Existing eNodeBs". In the procedure, modify parameters according to Using the CME to Perform Batch Configuration for Existing eNodeBs. Scenario 1: DRX is disabled, or DRX is enabled and the long DRX cycle is less than 160 ms. Issue 02 (2015-11-03)
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MO
Sheet in the Summary Data File
Parameter Group
Remarks
TimeAlignm entTimer
TimeAlignmentTimer
Local cell ID, Timing Measurement Mode, Uplink time alignment timer
l 0 is recommended for the Local cell ID parameter. l INVALID(Invalid Timing Measurement Mode) is recommended for the Timing measurement mode parameter. l SF1920(1920 subframes) is recommended for the Uplink time alignment timer parameter if the TimeAlignmentTimer.TimingAdvCmdOptSwitch parameter is set to OFF(Off). l SF10240(10240 subframes) is recommended for the Uplink time alignment timer parameter if the TimeAlignmentTimer.TimingAdvCmdOptSwitch parameter is set to ON(On).
Scenario 2: DRX is enabled and the long DRX cycle is greater than or equal to 160 ms.
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MO
Sheet in the Summary Data File
Parameter Group
Remarks
TimeAlignm entTimer
TimeAlignmentT imer
Local cell ID, Timing Measurement Mode/ Uplink timing advance command optimization switch/ Uplink time alignment timer
l 0 is recommended for the Local cell ID parameter. l INVALID(Invalid Timing Measurement Mode) is recommended for the Timing measurement mode parameter. l OFF(Off) is recommended for the Uplink timing advance command optimization switch parameter. l SF10240(10240 subframes) is recommended for the Uplink time alignment timer parameter.
Using the CME to Perform Single Configuration On the CME, set parameters according to Section "Configuring eNodeBs in Batches". For detailed instructions, see Using the CME to Perform Single Configuration described for feature activation.
Using MML Commands Scenario 1: DRX is disabled, or DRX is enabled and the long DRX cycle is less than 160 ms. Step 1 Run the MOD TATIMER command to configure the timing measurement mode and the length of the uplink time alignment timer. ----End Scenario 2: DRX is enabled and the long DRX cycle is greater than or equal to 160 ms. Step 1 Run the MOD TATIMER command to configure the timing measurement mode, length of the uplink time alignment timer, and uplink Timing Advance Command optimization switch. ----End
MML Command Examples Scenario 1: DRX is disabled, or DRX is enabled and the long DRX cycle is less than 160 ms. Issue 02 (2015-11-03)
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If the TimeAlignmentTimer.TimingAdvCmdOptSwitch parameter is set to OFF(Off), SF1920(1920 subframes) is recommended for the Uplink time alignment timer parameter. MOD TATIMER: LocalCellId=0, TimingMeasMode=INVALID, TimeAlignmentTimer=SF1920;
If the TimeAlignmentTimer.TimingAdvCmdOptSwitch parameter is set to ON(On), SF10240(10240 subframes) is recommended for the Uplink time alignment timer parameter. MOD TATIMER: LocalCellId=0, TimingMeasMode=INVALID, TimeAlignmentTimer=SF10240;
Scenario 2: DRX is enabled and the long DRX cycle is greater than or equal to 160 ms. MOD TATIMER: LocalCellId=0, TimingMeasMode=INVALID, TimeAlignmentTimer=SF10240, TimingAdvCmdOptSwitch=OFF;
6.4.6 Reconfiguration The following table describes the parameters that must be set in the RrcConnStateTimer MO to configure the uplink synchronization timer length and the length of the UE inactivity timer. Parameter Name
Parameter ID
Source
Setting Notes
Uplink Sync Timer
RrcConnState Timer.UlSynTi mer
Network plan (negotiation not required)
This parameter indicates the timer used to govern the period in which the eNodeB maintains uplink synchronization for a UE. After this timer expires, the eNodeB does not send Timing Advance Command to the UE. The default value for this parameter is 180.
Ue inactive timer
RrcConnState Timer.UeInacti veTimer
Network plan (negotiation not required)
This parameter indicates the duration within which the eNodeB receives or sends data to the UE. The default value for this parameter is 20.
MML Command Examples MOD RRCCONNSTATETIMER: UlSynTimer=180, UeInactiveTimer=20;
6.5 Performance Monitoring The operation of LBFD-070101 Uplink Timing Based on PUCCH can be monitored based on the counters in Table 6-2.
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Table 6-2 Counters related to uplink timing control Counter ID
Counter Name
Description
1526730143
L.Traffic.User.TAMeas.PUCCH .Avg
This counter specifies the average number of users whose uplink timing offsets are measured based on the PUCCH.
1526730144
L.Traffic.User.TAMeas.PUCCH .Max
This counter specifies the maximum number of users whose uplink timing offsets are measured based on the PUCCH.
1526728764
L.ChMeas.PRB.PUSCH.Avg
This counter specifies the number of used PRBs in the PUSCH.
1526728304
L.ChMeas.CCE.ULUsed
This counter specifies the number of CCEs in the PDCCH used to carry DCIs for uplink transmission.
1526728566 to 1526728597
L.ChMeas.PUSCH.MCS.0~ L.ChMeas.PUSCH.MCS.31
These counters specify the number of times that MCS index 0 to 31 is scheduled on the PUSCH
After LBFD-070101 Uplink Timing Based on PUCCH is enabled, the uplink timing offsets of some UEs in a cell are measured based on the CQI in PUCCH, which reduces radio resources consumed by uplink timing offset measurement based on the DMRS for PUSCH. Therefore, the actual number of CCCH blocks for paging can be calculated as follows: l
Observe the L.Traffic.User.TAMeas.PUCCH.Avg counter to obtain the average number of users whose uplink timing offsets are measured based on the PUCCH.
l
Observe the L.Traffic.User.TAMeas.PUCCH.Max counter to obtain the maximum number of users whose uplink timing offsets are measured based on the PUCCH.
l
Observe the L.ChMeas.PRB.PUSCH.Avg counter to verify that the number of used PRBs in the PUSCH decreases.
l
Observe the L.ChMeas.CCE.ULUsed counter to verify that the number of CCEs in the PDCCH used to carry DCIs for uplink transmission decreases.
l
Observe counters from L.ChMeas.PUSCH.MCS.0 to L.ChMeas.PUSCH.MCS.31 to verify that the number of scheduling times in the PUSCH decreases. The number of scheduling times in the PUSCH is the value of the sum of counters from L.ChMeas.PUSCH.MCS.0 to L.ChMeas.PUSCH.MCS.31.
6.6 Parameter Optimization When DRX is enabled, scheduling request (SR) false detections cause unnecessary uplink scheduling, which consumes air interface resources and reduces gains generated by LBFD-070101 Uplink Timing Based on PUCCH. PUSCH discontinuous transmission (DTX) detections help avoid unnecessary uplink scheduling caused by SR false detections. Therefore, if both DRX and LBFD-070101 Uplink Timing Based on PUCCH are enabled, you are advised to enable PUSCH DTX detection. Issue 02 (2015-11-03)
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6.7 Troubleshooting None
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7
Parameters
Table 7-1 Parameters MO
Parame ter ID
MML Comma nd
Feature ID
Feature Name
Description
TimeAli gnment Timer
TACmd SendPer iod
MOD TATIM ER
None
None
Meaning: Indicates the interval for sending the Timing Advance Command to UEs. This parameter needs to be set only when the TimingAdvCmdOptSwitch parameter is set to ON. If this parameter is set to Invalid, none of parameter settings in the MML Command window takes effect.
LST TATIM ER
GUI Value Range: INVALID(NULL), SF218(218 subframes), SF343(343 subframes), SF608(608 subframes), SF928(928 subframes), SF1248(1248 subframes), SF2528(2528 subframes), SF5088(5088 subframes) Unit: None Actual Value Range: INVALID, SF218, SF343, SF608, SF928, SF1248, SF2528, SF5088 Default Value: SF928(928 subframes)
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7 Parameters
MO
Parame ter ID
MML Comma nd
Feature ID
Feature Name
Description
TimeAli gnment Timer
Timing MeasMo de
MOD TATIM ER
LBFD-0 70101
Uplink Timing Based on PUCCH
Meaning: Indicates the method of measuring uplink timing offsets. If this parameter is set to INVALID, uplink timing offsets are measured based on the demodulation reference signal (DMRS) for PUSCH or sounding reference signal (SRS). If this parameter is set to ALLMEASMODE, uplink timing offsets are measured based on the DMRS for PUSCH and SRS or based on the DMRS for PUSCH and channel quality indicator (CQI) in PUCCH. In addition, the value ON of the TimingAdvCmdOptSwitch parameter takes effect regardless of the actual parameter setting. That is, the eNodeB always sends the Timing Advance Command to UEs. In this case, it is recommended that the TimeAlignmentTimer parameter be set to SF10240. The value ALLMEASMODE applies only to LTE FDD cells. The parameter value INVALID takes effect in a cell regardless of the actual parameter setting in any of the following scenarios: (1) The cell is established on an LBBPc. (2) The UlCyclicPrefix parameter is set to EXTENDED_CP. (3) The HighSpeedFlag parameter is set to HIGH_SPEED, ULTRA_HIGH_SPEED, or EXTRA_HIGH_SPEED. (4) The TX/RX mode of the cell is 2T8R.
LST TATIM ER
GUI Value Range: INVALID(Invalid Timing Measurement Mode), ALLMEASMODE(All Timing Measurement Mode) Unit: None Actual Value Range: INVALID, ALLMEASMODE Default Value: INVALID(Invalid Timing Measurement Mode)
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MO
Parame ter ID
MML Comma nd
Feature ID
Feature Name
Description
TimeAli gnment Timer
Timing ResOptS witch
MOD TATIM ER
None
None
Meaning: Indicates whether to enable the mechanism of optimized resource scheduling for uplink timing.If this parameter is set to OFF, the eNodeB adopts the existing resource scheduling policy for uplink timing, which consumes a large amount of resources used for delivering Timing Advance Commands in large traffic scenarios.If this parameter is set to ON, the eNodeB adopts the mechanism of optimized resource scheduling for uplink timing, which reduces the number of unnecessary Timing Advance Commands to be delivered and reduces resources allocated for uplink timing in large traffic scenarios.This parameter applies only to LTE FDD cells. The parameter value ON is recommended in heavily loaded cells where there is a large number of UEs.
LST TATIM ER
GUI Value Range: OFF(Off), ON(On) Unit: None Actual Value Range: OFF, ON Default Value: ON(On) TimeAli gnment Timer
Timing AdvCm dOptSwi tch
MOD TATIM ER LST TATIM ER
None
None
Meaning: Indicates whether optimization of the mechanism for delivering the uplink time alignment command takes effect. If the optimization takes effect, the number of unnecessary uplink time alignment commands delivered to motionless or low-mobility UEs can be reduced to save air interface resources and reduce power consumption of UEs in DRX mode. This ensures the uplink time alignment performance if the length of the uplink time alignment timer is set to a large value. If this parameter is set to ON, it is recommended that the TimeAlignmentTimer parameter be set to SF10240. A smaller value of the TimeAlignmentTimer parameter, such as SF5120, leads to a higher probability of becoming out-of-synchronization in the uplink for UEs in DRX mode. If this parameter is set to ON, it is recommended that the LongDrxCycle parameter be smaller than or equal to SF320. Otherwise, the uplink time alignment performance of UEs in DRX mode is affected. GUI Value Range: OFF(Off), ON(On) Unit: None Actual Value Range: OFF, ON Default Value: ON(On)
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MO
Parame ter ID
MML Comma nd
Feature ID
Feature Name
Description
TimeAli gnment Timer
TimeAli gnment Timer
MOD TATIM ER
None
None
Meaning: Indicates the length of the uplink time alignment timer for UEs in the cell. A UE is considered not time-aligned in the uplink if the timer expires.
LST TATIM ER
GUI Value Range: SF500(500 subframes), SF750(750 subframes), SF1280(1280 subframes), SF1920(1920 subframes), SF2560(2560 subframes), SF5120(5120 subframes), SF10240(10240 subframes), INFINITY(Infinity) Unit: None Actual Value Range: SF500, SF750, SF1280, SF1920, SF2560, SF5120, SF10240, INFINITY Default Value: INFINITY(Infinity)
RrcCon nStateTi mer
UlSynTi mer
MOD RRCCO NNSTA TETIM ER
LBFD-0 02007 / TDLBF D-00200 7
RRC Connect ion Manage ment
LST RRCCO NNSTA TETIM ER
Meaning: Indicates the timer used to govern the period in which the eNodeB maintains uplink synchronization for a UE. After this timer expires, the eNodeB does not send Timing Advance Command to the UE. This parameter does not take effect if it is set to 0. That is, the eNodeB will constantly send Timing Advance Command to the UE to maintain uplink synchronization for the UE. GUI Value Range: 0~3600 Unit: s Actual Value Range: 0~3600 Default Value: 180
RrcCon nStateTi mer
UeInacti veTimer
MOD RRCCO NNSTA TETIM ER LST RRCCO NNSTA TETIM ER
LBFD-0 02007 / TDLBF D-00200 7
RRC Connect ion Manage ment
Meaning: Indicates the length of the UE inactivity timer for UEs that are running non-QCI1 services. If the eNodeB detects that a UE has neither received nor sent data for a duration exceeding the value of this parameter, the eNodeB releases the RRC connection for the UE. If this parameter is set to 0, the UE inactivity timer is not used. If the parameter setting is changed, the change applies to UEs that newly access the network. GUI Value Range: 0~3600 Unit: s Actual Value Range: 0~3600 Default Value: 20
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7 Parameters
MO
Parame ter ID
MML Comma nd
Feature ID
Feature Name
Description
Cell
HighSpe edFlag
ADD CELL
LOFD-0 01007 / TDLOF D-00100 7
High Speed Mobility
Meaning: Indicates the speed flag of the cell. Set this parameter to HIGH_SPEED if the cell is used to provide coverage for an ultra-high-speed railway. Set this parameter to LOW_SPEED in other scenarios. TDD cells with a bandwidth of 5 MHz or in 8T8R mode can only be configured as low speed cells. TDD cells don't support ULTRA_HIGH_SPEED mode.
MOD CELL LST CELL
LOFD-0 01008
Ultra High Speed Mobility
GUI Value Range: LOW_SPEED(Low speed cell flag), HIGH_SPEED(High speed cell flag), ULTRA_HIGH_SPEED(Ultra high speed cell flag), EXTRA_HIGH_SPEED(Extra high speed cell flag) Unit: None Actual Value Range: LOW_SPEED, HIGH_SPEED, ULTRA_HIGH_SPEED, EXTRA_HIGH_SPEED Default Value: LOW_SPEED(Low speed cell flag) Cell
UlCycli cPrefix
ADD CELL MOD CELL LST CELL
LBFD-0 0100401 / TDLBF D-00100 401 LOFD-0 01031 / TDLOF D-00103 1 LBFD-0 02009 / TDLBF D-00200 9
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Normal CP Extende d CP Broadca st of system informat ion
Meaning: Indicates the UL cyclic prefix length of a cell. A cyclic prefix can be a common or extended cyclic prefix. An extended cyclic prefix is generally used in a complex environment with a strong multipath effect and long delay. In a cell, the UL cyclic prefix length can be different from the DL one. In addition, the UL or DL cyclic prefix length of a cell must be the same as that of the cell using the same BBP. For details, see 3GPP TS 36.211. GUI Value Range: NORMAL_CP(Normal), EXTENDED_CP(Extended) Unit: None Actual Value Range: NORMAL_CP, EXTENDED_CP Default Value: NORMAL_CP(Normal)
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7 Parameters
MO
Parame ter ID
MML Comma nd
Feature ID
Feature Name
Description
SRSCfg
SrsCfgI nd
MOD SRSCF G
LBFD-0 02003 / TDLBF D-00200 3
Physical Channel Manage ment
Meaning: Indicates whether to configure sounding reference signal (SRS) resources for UEs in a cell. The value BOOLEAN_TRUE indicates that SRS resources are available in the cell and can be configured for UEs in the cell. The value BOOLEAN_FALSE indicates that no SRS resource is available in the cell, and therefore no UE in the cell is configured with SRS resources. This parameter does not take effect on: (1) FDD cell that is established on an LBBPc and uses four or more RX antennas. (2) FDD cell that is established on an LBBPc and uses extended cyclic prefix (CP) in the uplink. (3) TDD cell established on an LBBPc. If this parameter does not take effect on a cell but SRS resources are available in the cell, SRS resources can be configured for UEs in the cell.
LST SRSCF G
GUI Value Range: BOOLEAN_FALSE(False), BOOLEAN_TRUE(True) Unit: None Actual Value Range: BOOLEAN_FALSE, BOOLEAN_TRUE Default Value: BOOLEAN_TRUE(True)
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8 Counters
8
Counters
Table 8-1 Counters Counter ID
Counter Name
Counter Description
Feature ID
Feature Name
1526727412
L.ChMeas.PUSCH. MCS.0
Number of times MCS index 0 is scheduled on the PUSCH
Multi-mode: None
Basic Scheduling
GSM: None
Modulation: DL/UL QPSK, DL/UL 16QAM, DL 64QAM
UMTS: None LTE: LBFD-002025 LBFD-001005 TDLBFD-002025 TDLBFD-001005
1526727443
L.ChMeas.PUSCH. MCS.31
Number of times MCS index 31 is scheduled on the PUSCH
Modulation: DL/UL QPSK, DL/UL 16QAM, DL 64QAM
Multi-mode: None
Basic Scheduling
GSM: None
Basic Scheduling
UMTS: None
Modulation: DL/UL QPSK, DL/UL 16QAM, DL 64QAM
LTE: LBFD-002025 TDLBFD-002025 LBFD-001005 TDLBFD-001005 LOFD-001006 TDLOFD-001006
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Basic Scheduling
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Modulation: DL/UL QPSK, DL/UL 16QAM, DL 64QAM UL 64QAM UL 64QAM
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Counter ID
Counter Name
Counter Description
Feature ID
Feature Name
1526728304
L.ChMeas.CCE.UL Used
Number of PDCCH CCEs used for uplink DCI in a measurement period
Multi-mode: None
Physical Channel Management
GSM: None UMTS: None LTE: LBFD-002003
Physical Channel Management
TDLBFD-002003 1526728333
L.Traffic.User.Ulsy nc.Avg
Average number of UL synchronized users in a cell
Multi-mode: None GSM: None UMTS: None LTE: LBFD-002007
RRC Connection Management RRC Connection Management
TDLBFD-002007 1526728481
L.Traffic.User.SRS. Avg
Average number of UEs configured with sounding reference signal (SRS) resources in a cell
Multi-mode: None GSM: None UMTS: None LTE: LBFD-002007
RRC Connection Management RRC Connection Management
TDLBFD-002007 1526728764
L.ChMeas.PRB.PU SCH.Avg
Average number of used PUSCH PRBs
Multi-mode: None
Basic Scheduling
GSM: None
Basic Scheduling
UMTS: None
Adaptive SFN/ SDMA
LTE: LBFD-002025 TDLBFD-002025 LOFD-070205 1526730143
1526730144
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L.Traffic.User.TAM eas.PUCCH.Avg
L.Traffic.User.TAM eas.PUCCH.Max
Average number of UEs whose uplink timing offsets are measured based on the PUCCH
Multi-mode: None
Maximum number of UEs whose uplink timing offsets are measured based on the PUCCH
Multi-mode: None
GSM: None
Uplink Timing Based on PUCCH
UMTS: None LTE: LBFD-070101
GSM: None
Uplink Timing Based on PUCCH
UMTS: None LTE: LBFD-070101
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eRAN Uplink Timing Control Feature Parameter Description
9 Glossary
9
Glossary
For the acronyms, abbreviations, terms, and definitions, see Glossary.
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37
eRAN Uplink Timing Control Feature Parameter Description
10
10 Reference Documents
Reference Documents
1.
3GPP TS 36.213, "Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures"
2.
3GPP TS 36.321, "Evolved Universal Terrestrial Radio Access (E-UTRA); Medium Access Control"
3.
DRX and Signaling Control Feature Parameter Description
4.
Random Access Control and RACH Optimization Feature Parameter Description
5.
Connection Management Feature Parameter Description
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