Nokia Academy
LTE1203 – Load-based Power Saving with Tx Path
Switching Off
RA4115 FL16 Feature Overview
RA41155EN162GLA0
© Nokia Solutions and Networks 2016
This page contains no comments
Copyright and confidentiality
The contents of this document are
proprietary and confidential property of
Nokia Solutions and Networks. This
document is provided subject to
confidentiality obligations of the applicable
agreement(s).
This document is intended for use of Nokia
Solutions and Networks customers and
collaborators only for the purpose for which
this document is submitted by Nokia
Solutions and Networks. No part of this
document may be reproduced or made
available to the public or to any third party in
any form or means without the prior written
permission of Nokia Solutions and Networks.
This document is to be used by properly
trained professional personnel. Any use of
the contents in this document is limited
strictly to the use(s) specifically created in
the applicable agreement(s) under which the
document is submitted. The user of this
document may voluntarily provide
suggestions, comments or other feedback to
Nokia Solutions and Networks in respect of
the contents of this document ("Feedback").
Such Feedback may be used in Nokia
Solutions and Networks products and related
specifications or other documentation.
Accordingly, if the user of this document
gives Nokia Solutions and Networks
feedback on the contents of this document,
Nokia Solutions and Networks may freely
use, disclose, reproduce, license, distribute
and otherwise commercialize the feedback
in any Nokia Solutions and Networks
product, technology, service, specification or
other documentation.
implied, including, but not limited to, the
implied warranties of merchantability and
fitness for a particular purpose, are made in
relation to the accuracy, reliability or
contents of this document. NOKIA
SOLUTIONS AND NETWORKS SHALL
NOT BE RESPONSIBLE IN ANY EVENT
FOR ERRORS IN THIS DOCUMENT or for
any loss of data or income or any special,
incidental, consequential, indirect or direct
damages howsoever caused, that might
arise from the use of this document or any
contents of this document.
Nokia Solutions and Networks operates a
policy of ongoing development. Nokia
Solutions and Networks reserves the right to
make changes and improvements to any of
the products and/or services described in
this document or withdraw this document at
any time without prior notice.
This document and the product(s) it
describes are protected by copyright
according to the applicable laws.
The contents of this document are provided
"as is". Except as required by applicable law,
no warranties of any kind, either express or
Nokia is a registered trademark of Nokia
Corporation. Other product and company
names mentioned herein may be trademarks
or trade names of their
respective owners.
© Nokia Solutions and Networks 2016
Confidential
2
RA41155EN162GLA0
Company Confidential
© Nokia Solutions and Networks 2016
This page contains no comments
1
LTE1203 – Load-based Power Saving with Tx Path Switching Off
Agenda
Feature Overview
Configuration and Testing
Test Results
Operational Hints and Guidelines
4
RA41155EN162GLA0
Company Confidential
© Nokia Solutions and Networks 2016
Page: 3
Number: 1
Author: Presenter
Subject: Presentation Notes Date: 2/4/2016 5:42:33 AM
The LTE1203 – Load-based Power Saving with Tx Path Switching Off feature provides energy saving modes,
in case of a low-load period, for cells configured for MIMO operations in the LTE technology.
◄ Back
Feature Overview
LTE1203 – Load-based Power Saving with Tx Path Switching Off
The LTE1203 – Load-based Power Saving with Tx Path Switching Off feature provides energy
saving modes, in case of a low-load period, for cells configured for MIMO operations.
The cells in the eNB can be grouped for power saving mode. These power group cells have the
same coverage and the load-based power saving cell switch off order (lbpsCellSOOrder)
parameter defines the order in which the power group cells are switched off.
Benefits of the feature:
• Power saving during off-peak hours, which results in OPEX savings by:
• Monitoring of the system to increase or reduce capacity as required,
• Efficiently limiting capacity based on load that allows to switch off paths of the system,
• Reduction of the capacity of each power group to only that which is required by the UEs
being serviced by the commercial system,
• Provides history of the power saving mode events for each eNB resource that is
controlled by the LTE1203 feature.
5
RA41155EN162GLA0
Company Confidential
© Nokia Solutions and Networks 2016
This page contains no comments
Feature Overview
Functional Description – Monitor Load Based Power Saving (LBPS; LTE1103, FL15A)
• The eNB monitors the load in the served cells and triggers cell switch off once all of the following
conditions are met:
-
During the time of the day defined by the user for cell switch off.
There are no ongoing emergency calls and no queued messages for Earthquake and Tsunami Warning System
(ETWS) or Commercial Mobile Alert System (CMAS) in the cell.
The complete load of the cells in the power saving group is below the low load threshold (evaluation period 5
minutes).
The estimated complete load immediately after cell switch off for the remaining active cells in the power saving
group does not exceed the high load threshold.
• A cell that is being shutdown will utilize the LTE914 Graceful Cell Shutdown feature to ramp down
power to allow UE to HO prior to being shut off.
• The cell is barred before it is switched off in the eNB. The traffic is moved to other cells during cell
switch off. The eNB turns the power amplifier to standby mode.
6
RA41155EN162GLA0
Company Confidential
© Nokia Solutions and Networks 2016
This page contains no comments
Feature Overview
Functional Description – Monitor Load Based Power Saving (LBPS; LTE1103, FL15A)
40
PSM = notEnergySavings
(03:55)
35
PSM = energySavings
(01:15)
30
PSM = notEnergySavings
(05:10)
PSM = energySavings
(01:15)
25
Operator Enabled?
20
Off-Threshold
On-Threshold
15
10
5
Actual Load
Operator set:
Load-Based
Power Savings
Period Start
(01:05)
Operator set:
Load-Based
Power Savings
Period Stop
(05:10)
0:00
0:10
0:20
0:30
0:40
0:50
1:00
1:10
1:20
1:30
1:40
1:50
2:00
2:10
2:20
2:30
2:40
2:50
3:00
3:10
3:20
3:30
3:40
3:50
4:00
4:10
4:20
4:30
4:40
4:50
5:00
5:10
5:20
5:30
5:40
5:50
6:00
0
Example of power saving mode operation in the eNB
7
RA41155EN162GLA0
Company Confidential
© Nokia Solutions and Networks 2016
This page contains no comments
1
Feature Overview
LTE1203 – Load-based Power Saving with Tx Path Switching Off
The LTE1203 – Load-based Power Saving with Tx Path Switching Off feature uses separate minimum
and maximum load thresholds to support different default values from those defined in the LTE1103
– Load-based Power Saving for Multi-layer Networks feature. The LTE1203 feature calculates the
power group load using the offset cell capacity of reduced Tx path cells.
8
RA41155EN162GLA0
Company Confidential
© Nokia Solutions and Networks 2016
Page: 7
Number: 1
Author: Presenter
Subject: Presentation Notes Date: 2/4/2016 5:42:35 AM
Each eNB independently decides the power saving state of its power group cells. LTE1203 does not support
any X2 data exchange between eNBs.
LTE1203 uses the same power group and cell switch off order parameters, the same power group and cell
switch-off order determination algorithms, the same last cell switch off enabled parameter, and the same
load counters that are defined for LTE1103.
In order to support different default values, LTE1203 uses separate minimum and maximum load thresholds
than those defined for LTE1103.
LTE1203 will also need to modify the load calculations based on cell capacity of reduced TX path cells
Feature Overview
LTE1203 – Feature relationships
9
RA41155EN162GLA0
Company Confidential
© Nokia Solutions and Networks 2016
This page contains no comments
1
Feature Overview
LTE1203 – Load-based Power Saving with Tx Path Switching Off
The cells in the eNB can be grouped for power saving mode. These power group cells have the same
coverage and the load-based power saving cell switch off order (lbpsCellSOOrder) parameter defines
the order in which the power group cells are switched off.
For power groups with cells that are configured for the NxN MIMO operation mode, the operator can
activate the LTE1203 feature to save energy during a low load by switching off a set of cell’s Tx
paths.
10
RA41155EN162GLA0
Company Confidential
© Nokia Solutions and Networks 2016
Page: 9
Number: 1
Author: Presenter
Subject: Presentation Notes Date: 2/4/2016 5:42:35 AM
When the resulting number of Tx antennas in the power saving mode is 2, each antenna must correspond
to a different polarization. The reduction of transmission antennas also affects the available set of
transmission modes. In case precoding vector switching (PVS) was activated in a cell for the primary
synchronization signal (PSS)/secondary synchronization signal (SSS) and/or positioning reference signal
(PRS), proper coding will be applied in the 2Tx cell. If a cell was modified to the 1Tx mode, PVS cannot be
used. For the 2Tx or 4Tx cells, the UEs needs to reconnect, and the best transmission modes will be used
from the available ones at the target number of Tx antennas. When exiting the power saving mode,
transmission on the previously muted antennas will resume with normal functionality after a cell reset.
1
Feature Overview
LTE1203 – Load-based Power Saving with Tx Path Switching Off
11
RA41155EN162GLA0
Company Confidential
© Nokia Solutions and Networks 2016
Page: 10
Number: 1
Author: Presenter
Subject: Presentation Notes Date: 2/4/2016 5:42:35 AM
Multi-layer coverage areas with TX paths switched off:
UEs at the edge of the impacted cell experience a drop in signal strength. These UEs may initiate hand over
to neighboring cells with a better signal strength. The load is increased at the neighboring cells, but the
overall power group load is maintained if the handover is to another cell in the power group.
UEs at the new edge of the impacted cell experience a slight drop in signal strength; the drop is not
sufficient to initiate handover.
UEs at the center of the power group coverage area; if too many UEs hand over from the impacted power
group cell to other cells serving the same coverage area, then load equalization may redistribute some UEs
at the center of the other power group cells into the impacted power group cell.
Multi-layer coverage areas with TX paths switched on:
UEs at the edge of the impacted cell experience an improved signal strength.
UEs at the new edge of the impacted cell experience an increase in the signal strength of the impacted cell.
Depending on UE measurements, UEs may hand over into the impacted cell.
There is no impact on the UEs at the center of the power group coverage area.
Feature Overview
Feature Interdependencies
The following features must be deactivated before activating the LTE1203 feature:
• LTE1542: FDD SuperCell
• LTE1709: Liquid Cell
Carrier aggregation (CA) is affected in the following manner:
• For 4TX and 2TX cells, the cell is reset when the cell transitions into or out of reduced energy
saving. Thus, if the cell is the Pcell, the UE disconnects from the Pcell. In this case, the Pcell and
assigned Scells are no longer allocated for CA. If the cell is an Scell, the UE disconnects from the
Scell and CA may continue to be allocated for the Pcell and other Scells.
12
RA41155EN162GLA0
Company Confidential
© Nokia Solutions and Networks 2016
This page contains no comments
Management Data
New Performance Measurement Counters
• New Counters by LTE1203
Counter ID
Counter name
Measurement
M8020C9
Number of samples when the cell is in reduced TX
power saving mode
8020 - LTE Cell Availability
M8020C10
Number of cell state changes to reduced TX power
saving mode
8020 - LTE Cell Availability
• Counters modified by LTE1203
13
Fault ID
Counter name
Measurement
M8020C2
Number of cell state changes to unplanned
unavailable
8020 - LTE Cell Availability
RA41155EN162GLA0
Company Confidential
© Nokia Solutions and Networks 2016
This page contains no comments
1
Management Data
New Parameters introduced by LTE1203
• New Parameters
14
Parameter Name
Abbreviated Name
Managed Object
Activate load-based reduced TX power saving
actLBRTXPowerSaving
LNBTS
Load-based power saving last cell reduced TX min load
lbpsLastCellRTXMinLoad
PSGRP
Load-based power saving reduced TX cell capacity offset
lbpsRTXCellCapOffset
PSGRP
Load-based power saving reduced TX maximum load
lbpsRTXMaxLoad
PSGRP
Load-based power saving reduced TX minimum load
lbpsRTXMinLoad
PSGRP
RA41155EN162GLA0
Company Confidential
© Nokia Solutions and Networks 2016
Page: 13
Number: 1
Author: Presenter
Subject: Presentation Notes Date: 2/4/2016 5:42:36 AM
Note:
Whether the LTE1203: Load-based Power Saving with Tx Path Switching Off feature acts on all cells or just
the lowest layer depends both on the actLBPowerSaving and actLBRTXPowerSaving parameter.
Management Data
Parameters already introduced by LTE1103 (FL15A)
15
Full name
Abbreviated name
Managed object
Structure
Activate load-based power saving
actLBPowerSaving
LNBTS
-
Energy saving state
energySavingState
LNCEL
-
Load-based power saving iSON control enabled
lbpsISONCtlEnabled
PSGRP
-
Load-based power saving last cell minimum load
lbpsLastCellMinLoad
PSGRP
-
Load-based power saving last cell switch off enabled
lbpsLastCellSOEnabled
PSGRP
-
Load-based power saving maximum load
lbpsMaxLoad
PSGRP
-
Load-based power saving minimum load
lbpsMinLoad
PSGRP
-
Load-based power saving PDCCH load offset
lbpsPdcchLoadOffset
PSGRP
-
Full name
Power saving group identifier
psGrpId
PSGRP
-
Load-based power saving cell list
lbpsCellList
PSGRP
-
Load-based power saving cell switch off order
lbpsCellSOOrder
PSGRP
lbpsCellList
LTE cell configuration identifier
lnCelId
PSGRP
lbpsCellList
Load-based power saving period list
lbpsPeriodList
PSGRP
-
Load-based power saving day of week
lbpsDayOfWeek
PSGRP
lbpsPeriodList
lbpsPeriodList
Load-based power saving duration
lbpsDuration
PSGRP
Load-based power saving start time hour
lbpsStartTimeHour
PSGRP
lbpsPeriodList
Load-based power saving start time minute
lbpsStartTimeMinute
PSGRP
lbpsPeriodList
Load-Based Power Saving Suspended
lbpsSuspended
PSGRP
lbpsPeriodList
RA41155EN162GLA0
Company Confidential
© Nokia Solutions and Networks 2016
This page contains no comments
◄ Back
Configuration and Testing
Activation of the LTE1203 and LTE1103 features, respectively
16
RA41155EN162GLA0
Company Confidential
© Nokia Solutions and Networks 2016
This page contains no comments
1
Configuration and Testing
Activation of the LTE1203 feature – Creating a Power Saving Group (similar to LTE1103)
New parameters introduced by LTE1203 – used in LTE1103 and LTE1203
17
RA41155EN162GLA0
Company Confidential
© Nokia Solutions and Networks 2016
Page: 16
Number: 1
Author: Presenter
Subject: Presentation Notes Date: 2/4/2016 5:42:37 AM
Load-based power saving reduced TX cell capacity offset (lbpsRTXCellCapOffset):
Defines the percent cell throughput at a reduced TX path cell relative to the full TX path cell throughput
expected due to the change in supported transmission mode due to reduction in cell TX paths.
The cell throughput is expected to decrease due to the change in supported transmission mode by the cell
with reduced TX paths.
Load-based power saving reduced TX maximum load (lbpsRTXMaxLoad):
Defines the high-watermark for the aggregate load of a power group for reduced TX power saving.
Load-based power saving reduced TX minimum load (lbpsRTXMinLoad):
Defines the low-watermark for the aggregate load of a power group for reduced TX power saving.
The eNB will switch off TX paths of a power group cell in cell switch off order if the aggregate power group
load is less than the low-watermark for reduced TX power saving value of lbpsRTXMinLoad for a minimum
duration and the expected aggregate power group load for the reduced aggregate power group capacity is
less than the high-water mark for reduced TX power saving value of lbpsRTXMaxLoad.
Configuration and Testing
Test setup
• Equipment:
- 1 eNB with minimum two cells operational and on different frequencies.
- Wireshark PC to monitor M-plane (for CCN OM messages).
- EMIL to monitor RRC messages.
- One UE to generate load.
- iPerf on UE and application server (optional), can be used to maintain a constant load to
determine if cells should be switched on or off.
• Configuration:
- Enable the feature with the parameter actLBRTXPowerSaving= ‘true’,
- Set the other parameters (PSGRP) accordingly,
18
RA41155EN162GLA0
Company Confidential
© Nokia Solutions and Networks 2016
This page contains no comments
Configuration and Testing
Test execution
• Observe the eNB behavior for the following settings:
- Activate only LBPS with Tx Path Switching Off (Activate only LTE1203);
- Attach a UE to one cell and generate some load; RRC indicates TM4;
- After a certain time (defined by the operator), one cell goes to „Reduced Energy Saving“ and RRC
indicates TM1.
- Activate (in addition to LTE1203) also the LTE1103 feature (LBPS).
- Observe the different eNB behavior for the two features.
19
RA41155EN162GLA0
Company Confidential
© Nokia Solutions and Networks 2016
This page contains no comments
1
◄ Back
Test Results
Cell#1 in “Reduced Energy Saving” state
20
RA41155EN162GLA0
Company Confidential
© Nokia Solutions and Networks 2016
Page: 19
Number: 1
Author: Presenter
Subject: Presentation Notes Date: 2/4/2016 5:42:38 AM
As soon as the configured Power Saving Start time is reached, the eNB turns OFF one MIMO path and the
cell changes the status to „Reduced Energy Saving“.
A couple of seconds later, the cell chages its state to „Disabled“ and shortly later (1 sec) back to „Enabled“.
Thus leads to a new call trace in EMIL, now indicating the transmission mode TM1 (Single Transmission
without MIMO).
1
Test Results
Cell#2 is “Not Energy Saving”
21
RA41155EN162GLA0
Company Confidential
© Nokia Solutions and Networks 2016
Page: 20
Number: 1
Author: Presenter
Subject: Presentation Notes Date: 2/4/2016 5:42:38 AM
While Cell #1 changed its state to „Reduced Energy Saving“ the other cell of the eNB stays in the state „Not
Energy Saving“.
1
Test Results
BOTH cells in “Reduced Energy Saving” states – accompanied with Alarms
22
RA41155EN162GLA0
Company Confidential
© Nokia Solutions and Networks 2016
Page: 21
Number: 1
Author: Presenter
Subject: Presentation Notes Date: 2/4/2016 5:42:38 AM
Without changing anything and waiting further 5 minutes, the other cell (#2) also goes to „Reduced Energy
Saving“ – accompanied by 2 faults:
Fault #4003: „Transmission Path Failure“
Fault #4090: „Cell power failure“
1
Test Results
Wireshark traces
23
RA41155EN162GLA0
Company Confidential
© Nokia Solutions and Networks 2016
Page: 22
Number: 1
Author: Presenter
Subject: Presentation Notes Date: 2/4/2016 5:42:39 AM
<?xml version="1.0" encoding="UTF-8"?>
<raml xmlns="raml21.xsd" version="2.1">
<cmData type="plan">
<header>
<log dateTime="Fri Dec 18 13:38:39 +0100 2015" action="create CCN" appInfo="SysAdapter">Delta
CCN</log>
</header>
<managedObject class="LNBTS" distName="MRBTS-65/LNBTS-65" operation="update" version="FL16">
<p name="actLBRTXPowerSaving">true</p>
</managedObject>
<managedObject class="PSGRP" distName="MRBTS-65/LNBTS-65/PSGRP-1" operation="update"
version="FL16">
<list name="lbpsCellList">
<item>
<p name="lbpsCellSOOrder">1</p>
<p name="lnCelId">1</p>
</item>
<item>
<p name="lbpsCellSOOrder">2</p>
<p name="lnCelId">2</p>
</item>
</list>
<list name="lbpsPeriodList">
<item>
<p name="lbpsDayOfWeek">Fri</p>
<p name="lbpsDuration">15</p>
<p name="lbpsStartTimeHour">13</p>
<p name="lbpsStartTimeMinute">45</p>
<p name="lbpsSuspended">notSuspended</p>
</item>
</list>
</managedObject>
<managedObject class="MRBTS" distName="MRBTS-65" operation="auto" version="FL16">
<p name="configDataRevisionNumber">680</p>
</managedObject>
</cmData>
</raml>
Test Results
EMIL traces: Initial rrcConnectionReconfiguration
},
antennaInfo explicitValue : {
transmissionMode tm4,
codebookSubsetRestriction n2TxAntenna-tm4 : '111111'B,
ue-TransmitAntennaSelection release : NULL
}
}
24
RA41155EN162GLA0
Company Confidential
© Nokia Solutions and Networks 2016
This page contains no comments
Test Results
EMIL traces: Later rrcConnectionReconfiguration
},
antennaInfo explicitValue : {
transmissionMode tm1,
ue-TransmitAntennaSelection release : NULL
}
}
25
RA41155EN162GLA0
Company Confidential
© Nokia Solutions and Networks 2016
This page contains no comments
This page contains no comments