zte umts intelligent carrier power off or on feature guide_v8 5_201312

Intelligent Carrier Power

Off/On Feature Guide

WCDMA RAN

Intelligent Carrier Power Off/On Feature Guide

ZTE Confidential Proprietary 1


Version Date Author Reviewer Revision History

7.0 2012-4-20 He Chao Xu Junping

1. According to “ZTE UMTS Node B

Management Feature

Guide_V6.0_201110.docx”, added the

description of intelligent carrier power

off/on based on the number of users in a

cell.

2. In section 2.1, modified “maximum

transmit power” to “CPICH power”.

3. In section 3.1.1, modifies the description

of the timer.

4. In section 3.2.1, modified “<” to “<=” in

the formula .

8.0 2013-04-28 He Chao Xu Junping

1. CloseFreFunSwit is modified from cell

level to RNC level, and related

description is modified.

2. Added three parameters omitted in the

previous revision: PcpiPwrDnStep,

PcpiPwrDnTmWin, and

PcpiPwrDnStepTm.

3. Supplemented "3.3 Carrier Power off".

4. Modified the counters.

8.5 2013-11-28 Zhang

Haiyan Xu Junping

1. Corrected edit errors.

2. Added Feature ID

© 2014 ZTE Corporation. All rights reserved.

ZTE CONFIDENTIAL: This document contains proprietary information of ZTE and is not to be disclosed or used

without the prior written permission of ZTE.

Due to update and improvement of ZTE products and technologies, information in this document is subjected to

change without notice.



TABLE OF CONTENTS

1 Feature Attributes .............................................................................................. 4

2 Overview ............................................................................................................ 4

2.1 ZWF21-20-017 Intelligent Carrier Power Off/On .................................................. 4

3 Technical Descriptions ..................................................................................... 5

3.1 Carrier Power-Off Checking Strategies ................................................................ 5

3.1.1 Strategy Based on the Number of In-Cell Users ................................................... 5

3.1.2 Strategy Based on Cell Load ............................................................................... 6

3.2 Carrier Power-On Checking Strategies ................................................................ 8

3.3 Carrier Power Off Procedure .............................................................................. 10

3.4 Carrier Power On Procedure .............................................................................. 11

4 Parameters and Configurations ..................................................................... 11

4.1 Intelligent Carrier Power Off/On Parameters ...................................................... 11

4.1.1 Intelligent Carrier Power off/on Parameters List ................................................. 11

4.1.2 Intelligent Carrier Power Off/On Parameters Configurations .............................. 12

5 Counters and Alarms ...................................................................................... 23

5.1 Counters List ...................................................................................................... 23

5.2 Alarms List ......................................................................................................... 23

6 Glossary ........................................................................................................... 24



FIGURES

Figure 3-1 Flow Chart for Carrier Closing Decision ............................................................. 6

Figure 3-2 Carrier Power Off Procedure.............................................................................10



1 Feature Attributes

System version: [RNC V4.11.20, Node B V4.12.10, OMMR V12.12.41, and OMMB

V12.12.40 ]

Attribute: [Optional]

Involved NEs:

UE Node B RNC MSCS MGW SGSN GGSN HLR

- √ √ - - - - -

Note:

*-: Not involved

* √: Involved

Dependency: [None]

Mutually exclusion: [None].

Note: [None]

2 Overview

2.1 ZWF21-20-017 Intelligent Carrier Power Off/On

The load in a mobile telecommunication system varies during a day. In rush hours,

multiple carries may be required to carry services. But late at night, one carrier may be

enough to satisfy the service demand. If multiple carriers are used when the traffic is low,

the load of each carrier is low but still occupies about 20% of the maximum transmit

power due to the transmission of common channels (such as pilot channels).

This feature is designed to automatically monitor the network traffic and close part

carriers when the traffic is low. If it is detected that the traffic increases and may exceed

the handling capacity of the current working carriers, the closed carriers are

automatically opened.



During the intelligent carrier closing period, the P-CPICH power of the cell is reduced

gradually until the cell is completely closed, and the services of the cell are handed over

to the adjacent cell smoothly.

3 Technical Descriptions

In a multi-carrier network, the operator can enable or disable the Intelligent Carrier Power

Off/On feature via the RNC-level switch closeFreFunSwit.

When closeFreFunSwit is set to ”On”, if the number of subscribers or load at a carrier is

low, the RAN automatically closes the carrier to save power. The power of pilot channel

is reduced gradually to avoid call drops when the carrier is being closed. The subscribers

in this cell are handed over to other carriers based on radio quality. If the working carrier

is in congestion, the RAN immediately opens the closed carrier.

3.1 Carrier Power-Off Checking Strategies

There are two algorithms for intelligent carrier power off checking, one is based on the

number of users in the cell, and the other is based on the cell load. Operators can

choose either algorithm via the parameter closeFreAlg for each cell.

freCloseAllowedInd is used to control whether the current carrier is allowed to be closed.

This parameter is configured for each cell.

When freCloseAllowedInd is equal to 0, the current carrier is not allowed to be closed.

The network planning personnel must ensure that the first carrier (which is used to

provide continuous coverage) is not allowed to be closed.

When freCloseAllowedInd is equal to 1, the current carrier is allowed to be closed.

3.1.1 Strategy Based on the Number of In-Cell Users

When closeFreFunSwit is set to “on”, for the cells for which carriers are allowed to be

closed (indicated by freCloseAllowedInd) and the closeFreAlg is set as “Based on the

User Number on CELL_DCH State to Switch Off Frequency”, the RNC checks whether



the condition is fulfilled for closing carriers during the time between startTimetoClsF and

endTimetoClsF.

When the time indicated by startTimetoClsF is reached, the RNC counts the number of

subscribers in Cell_DCH state in the cell. If the number is lower than the threshold

indicated by ueNumThreshCls in the duration indicated by freClsOpnTrigTm, a carrier

closing procedure is triggered.

Figure 3-1 shows the decision procedure for carrier closing.

Figure 3-1 Flow Chart for Carrier Closing Decision

The time indicated by startTimetoClsF is reached?

Count the number of users (UserNum) in

Cell_DCH

UserNum < ueNumThreshCls?

Start the timer CellCloseTime (initial value =

freClsOpnTrigTm)

UserNum is greater than or equal to ueNumThreshCls

before CellCloseTimer expires?

Stop the timer CellCloseTime

UserNum is decreased?

Start closing the carrier

Y

N

N

Y

Y

N

N

Y

3.1.2 Strategy Based on Cell Load

When there are many flat tariff users in the network, who are always online for 24 hours a

day to download audio or video., Intelligent Carrier Power Off/On Based on the Number



of In-Cell Users is hard to take effect. Intelligent Carrier Power Off/On Based on Cell

Load is presented, which allows the carrier to be closed when the remained carriers can

fulfill the current users’ basic QoS requirement.

In the scenario of multi-layer, the RNC sets a priority for each carrier according to the

strategy of Intelligent Carrier Power Off/On Checking Based on Cell Load. The priority is

indicated by freClosePri, which can be configured for each cell according to the

operator’s requirement.

In a certain area covered by multi-layer cells (having Overlap or Covers relationship

indicated by ShareCover), the selection of the carrier to be closed always begins from

the cell with the lowest priority. If more than one cell has the same priority, the one with

the fewest users in CELL_DCH state is selected. If more than one cell has the same

number of users in CELL_DCH state, the one with the smallest Cell ID is selected.

When closeFreFunSwit is set to “on”, for the cell for which the carrier is allowed to be

closed (indicated by freCloseAllowedInd) and the closeFreAlg is set as “Based on the

Cell Load to Switch Off Frequency”, the RNC checks whether the condition is fulfilled for

closing a carrier during the time between startTimetoClsF and endTimetoClsF.

In order to guarantee that the load of the current cell can be carried by neighboring cells,

cell resources are all evaluated before the carrier closing. The carrier closing is triggered

only if all the resources fulfill the following condition in the duration indicated by

freClsOpnTrigTm:

Effective load of the cell to be closed <= ∑ (Admission threshold of the neighboring cells

with Overlap or Covers relationship - LoadMarginClose – current resource consumption

of the neighboring cells with Overlap or Covers relationship

LoadMarginClose is the load margin configured respectively for different kinds of cell

resources. For the downlink transmit power, uplink interference, channelization code,

uplink CE resource, downlink CE resource, number of users on HSDPA, and the number

of users on HSUPA, the corresponding LoadMarginClose parameters are

powerMarginClose, intMarginClose, codeMarginClose, ulCeMarginClose,

dlCeMarginClose, hsNumMarginClose, and eNumMarginClose respectively.

The parameter freClsCeEvaInd is used to control whether CE resources are evaluated.



Note: The carrier cannot be closed if there is a neighboring cell with Overlap or Covers

relationship in congestion.

3.2 Carrier Power-On Checking Strategies

After a carrier is closed via this feature, there are four algorithms to power on the cell.

Which algorithm is adopted depends on the parameter openFreAlg.

If the value of openFreAlg is 0, the algorithm based on time is adopted. When the

time indicated by endTimetoClsF is reached, the intelligently closed cell is opened.

If the value of openFreAlg is 1, the algorithm based on congestion is adopted. If the

working carrier is in congestion, the RNC opens all the closed adjacent cells.

Whether the cell is congested is determined by the congestion algorithm. Refer to

the congestion control feature guide.

If the value openFreAlg is 2, the algorithm based on time or congestion is adopted.

If the value of openFreAlg is 3, the algorithm based on time or cell load is adopted.

When either of the following conditions is fulfilled, the closed carrier is switched on

immediately.

Condition 1: The time indicated by endTimetoClsF is reached.

Condition 2: (Effective load of the working carrier) > ∑ (Admission threshold of the

working carrier - LoadMarginOpen).

LoadMarginOpen is the load margin configured respectively for different kinds of

resources. For the downlink transmit power, uplink interference, channelization code,

uplink CE resource, downlink CE resource, number of users on HSDPA, and the number

of users on HSUPA, the corresponding LoadMarginOpen parameters are

powerMarginOpen, intMarginOpen, codeMarginOpen, ulCeMarginOpen,

dlCeMarginOpen, hsNumMarginOpen, and eNumMarginOpen respectively.

The parameter freClsCeEvaInd determines whether CE resources are evaluated.

If more than one inter-frequency neighboring cell can be opened, these cells are opened



one by one in the following order:

1. Neighboring cell with “Overlap” relationship

2. Neighboring cell with “Covers” relationship

3. Neighboring cell with “Contained in” relationship

For example, in the following figure, cell 1 and cell 2 have an “Overlap” relationship

with each other, cell 4 has a “Covers” relationship with cell 3, and cell 3 has a

“Contained in” relationship with cell 4.

For the neighboring cell with an “Overlap” or “Covers” relationship, only one carrier

is opened at a time and the carrier with the highest priority is firstly opened

according to the freClosePri. If more than one carrier has the highest priority, the

carrier to be opened is chosen randomly.

For the neighboring cell with a ”Contained in" relationship, all the carriers are

opened at the same time. For example, in the following figure, cell 1 and cell 2 have

a “Contained in” relationship with cell 3. When cell 3 is in congestion, cell 1 and cell

2 are opened at the same time.

Note: For algorithm 3, when the working carrier is in congestion state, all the closed

carrier in neighboring cells with “Overlap” or “Covers” relationship are opened

immediately.

After a closed cell is opened by any of the above algorithms, a punishment timer

indicated by forbTimAftOpnF is started to avoid ping-pong. Before the expiration of the

Cell3

Cell1 Cell2

Cell 4 Cell 1/2

Cell 3



timer, the cell will not be closed again even if it meets the carrier closing condition.

3.3 Carrier Power Off Procedure

When the cell is determined to be closed in accordance with a strategy, the RNC informs

the Node B to gradually power down CPICH for a cell via cell reconfiguration procedure.

The carrier power off procedure is shown in Figure 3-2. When the carrier power-off

procedure starts, the CPICH power is decreased step by step. The step size is indicated

by PcpiPwrDnStep. Each time the CPICH power is decreased, a time interval of

PcpiPwrDnTmWin is set. When the time interval is reached, the CPICH power is

decreased again. If the CPICH power is still higher than -10dBm after being decreased

for the maximum of PcpiPwrDnStepTm times, it is configured to -10dBm at the

(PcpiPwrDnStepTm +1) times. Once the CPICH power is down to -10dBm, the Node B

closes the carrier completely. The Node B enters the power saving state.

Figure 3-2 Carrier Power Off Procedure

CPICH Power

t

Users are handed over to the adjacent cells gradually

Carrier power off starts

Carrier power off ends

PcpiPwrDnTmWin

PcpiPwrDnStep

-10dBm

During downgrading the power of a cell, if a cell reconfiguration fails, the RNC stops

closing the cell and the cell remains its current state. When a cell is in power saving state,

if the cell is deleted and then re-established successfully, the cell will operate properly.

After the time when carrier power off is allowed is reached, the RNC determines whether

to close the cell again.



3.4 Carrier Power On Procedure

When the cell is determined to be opened in accordance with a strategy, the RNC

configures the transmit power of CPICH to the value indicated by PcpichPwr, via a cell

reconfiguration procedure. If the cell reconfiguration fails to recover the cell from power

saving state, the cell is kept in power saving state until the next check for carrier power

on.

4 Parameters and Configurations

4.1 Intelligent Carrier Power Off/On Parameters

4.1.1 Intelligent Carrier Power off/on Parameters List

Abbreviated Name Parameter Name

closeFreFunSwit Switch of Frequency Intelligently Function

startTimetoClsF Start Time to Switch Off Frequency Intelligently

endTimetoClsF End Time to Switch Off Frequency Intelligently

ueNumThreshCls UE Number Threshold Used for Switching Off Frequency

Intelligently

forbTimAftOpnF Forbidden Time of Switching Off After Switching On the

Frequency

freClsOpnTrigTm Trigger Time of Judgment Switching ON/Off Frequency

Intelligently

openFreAlg Switch of Algorithm Used to Switch On the Frequency

Intelligently

closeFreAlg Switch of Algorithm Used to Switch Off the Frequency

Intelligently

powerMarginClose DL Power Margin for Frequency Switch Off Judgement

intMarginClose UL Interference Margin for Frequency Switch Off Judgement

codeMarginClose DL Code Margin for Frequency Switch Off Judgement

ulCeMarginClose UL CE Margin for Frequency Switch Off Judgement

dlCeMarginClose DL CE Margin for Frequency Switch Off Judgement



Abbreviated Name Parameter Name

hsNumMarginClose HSDPA User Number Margin for Frequency Switch Off

Judgement

eNumMarginClose HSUPA User Number Margin for Frequency Switch Off

Judgement

powerMarginOpen DL Power Margin for Frequency Switch On Judgement

intMarginOpen UL Interference Margin for Frequency Switch On Judgement

codeMarginOpen DL Code Margin for Frequency Switch On Judgement

ulCeMarginOpen UL CE Margin for Frequency Switch On Judgement

dlCeMarginOpen DL CE Margin for Frequency Switch On Judgement

hsNumMarginOpen HSDPA User Number Margin for Frequency Switch On

Judgement

eNumMarginOpen HSUPA User Number Margin for Frequency Switch On

Judgement

freClosePri Priority of Frequency Switch Off

freClsCeEvaInd Indication of CE Evaluation for Switching Off Frequency

Intelligently

freCloseAllowedInd Indication of Whether the Frequency Switch Off is Allowed or

not

PcpiPwrDnStep P-CPICH Power Down Step Size Used to Switch Off

Frequency Intelligently

PcpiPwrDnTmWin Time Interval between Two Downgrade of P-CPICH Power

Used to Switch Off Frequency Intelligently

PcpiPwrDnStepTm Times of Downgrade of P-CPICH Power with Equal Step Used

to Switch off Frequency Intelligently

ShareCover Share Cover Indication

PcpichPwr P-CPICH Power

4.1.2 Intelligent Carrier Power Off/On Parameters Configurations

4.1.2.1 Switch of Frequency Intelligently Function

OMC path



GUI: Managed Element->UMTS Logical Function Configuration->UTRAN

Cell->UTRAN Cell

Parameter configuration

This parameter indicates whether the Intelligent Carrier Power Off/On feature is

supported. When it is set to 1, the Intelligent Carrier Power Off/On feature is

enabled. Otherwise, the feature is disabled.

4.1.2.2 Start Time to Switch Off Frequency Intelligently

OMC path


Cell->Extended Info of UTRAN Cell


This parameter indicates the start time when intelligent carrier powering off is

allowed. It is displayed as an absolute time, in the format of “hour, minute, second”.

When the indicated time is reached, if this cell is allowed to close the carrier

intelligently, the conditions for carrier power off will be checked.

4.1.2.3 End Time to Switch Off Frequency Intelligently

OMC path




This parameter indicates the end time when intelligent carrier powering off is

allowed. It is displayed as an absolute time, in the format of “hour, minute, second”.

When the indicated time is reached, this cell is not allowed to close the carrier

intelligently. If the cell is in power saving state and the time-based mode is used, the

cell will be powered on when the end time is reached.



4.1.2.4 UE Number Threshold Used for Switching Off Frequency Intelligently

OMC path




This parameter indicates the threshold for intelligent carrier power off. If the number

of subscribers in Cell_DCH state in a cell is not greater than the value indicated by

the parameter, the condition of carrier power off is met.

4.1.2.5 Forbidden Time of Switching Off After Switching On the Frequency

OMC path




This parameter indicates the forbidden time interval for powering off a cell again

after recovering it from power saving state. The unit is hour and the range is from

0.1 to 24 with a step of 0.1. After a cell recovers from power saving state, the timer

forbTimAftOpnF is started. Before the expiry of the timer, the cell cannot be shut

down again even it fulfills the condition of intelligent carrier power off.

4.1.2.6 Trigger Time of Judgment Switching ON/Off Frequency Intelligently

OMC path






This parameter indicates the trigger time for a decision of intelligent carrier power

off or on. When the condition is satisfied during the time period specified by

freClsOpnTrigTm, the cell is switched off or on.

4.1.2.7 Switch of Algorithm Used to Switch On the Frequency Intelligently

OMC path




This parameter decides the algorithm used to power on a cell in power saving state.

If its value is 0, the time-based algorithm is used. If its value is 1, the

congestion-based algorithm is used. If its value is 2, the algorithm based on time

and congestion is used. If its value is 3, the algorithm based on time or cell load is

used.

4.1.2.8 Switch of Algorithm Used to Switch Off the Frequency Intelligently

OMC path




This parameter indicates the algorithm used to power off the carrier intelligently. If

the value is 0, the algorithm based on the number of users in CELL_DCH state is

used to switch off the carrier. If the value is 1, the algorithm based on the cell load is

used to switch off the carrier.

4.1.2.9 DL Power Margin for Frequency Switch Off Judgment

OMC path






This parameter indicates the DL power margin that must be considered when the

neighboring cell makes a power off decision. A larger value is recommended when

the cell has more than one contained neighboring cell.

4.1.2.10 UL Interference Margin for Frequency Switch Off Judgment

OMC path




This parameter indicates the UL interference margin that must be considered when

the neighboring cell makes a power off decision. A larger value is recommended

when the cell has more than one contained neighboring cell.

4.1.2.11 DL Code Margin for Frequency Switch Off Judgment

OMC path




This parameter indicates the DL code margin that must be considered when the



4.1.2.12 UL CE Margin for Frequency Switch Off Judgment

OMC path






This parameter indicates the UL CE margin that must be considered when the



4.1.2.13 DL CE Margin for Frequency Switch Off Judgment

OMC path




This parameter indicates the DL CE margin that must be considered when the



4.1.2.14 HSDPA User Number Margin for Frequency Switch Off Judgment

OMC path




This parameter indicates the HSDPA user number margin that must be considered

when the neighboring cell makes a power off decision. A larger value is

recommended when the cell has more than one contained neighboring cell.

4.1.2.15 HSUPA User Number Margin for Frequency Switch Off Judgment

OMC path






This parameter indicates the HSUPA user number margin that must be considered

when the neighboring cell makes a power off decision. A larger value is


4.1.2.16 DL Power Margin for Frequency Switch On Judgment

OMC path




This parameter indicates the DL power margin that must be considered when the



4.1.2.17 UL Interference Margin for Frequency Switch On Judgment

OMC path




This parameter indicates the UL interference margin that must be considered when

the neighboring cell makes a power off decision. A larger value is recommended

when the cell has more than one contained neighboring cell.

4.1.2.18 DL Code Margin for Frequency Switch On Judgment

OMC path






This parameter indicates the DL code margin that must be considered when the

neighboring cell makes a power on decision. A larger value is recommended when


4.1.2.19 UL CE Margin for Frequency Switch On Judgment

OMC path




This parameter indicates the UL CE margin that must be considered when the



4.1.2.20 DL CE Margin for Frequency Switch On Judgment

OMC path




This parameter indicates the DL CE margin that must be considered when the



4.1.2.21 HSDPA User Number Margin for Frequency Switch On Judgment

OMC path






This parameter indicates the HSDPA user number margin that must be considered

when the neighboring cell makes a power on decision. A larger value is


4.1.2.22 HSUPA User Number Margin for Frequency Switch On Judgment

OMC path




This parameter indicates the HSUPA user number margin that must be considered

when the neighboring cell makes a power on decision. A larger value is


4.1.2.23 Priority of Frequency Switch Off

OMC path


Cell->UTRAN Cell


This parameter indicates the priority of the carrier to be powered off intelligently. “0”

indicates the highest priority. The lower the priority of a carrier, the more probable

the carrier is to be powered off. It is recommended to set higher priorities for cells

supporting R99+R5+R6 than those supporting R99 only, and set higher priorities for

larger cells than smaller ones.



4.1.2.24 Indication of CE Evaluation for Switching Off Frequency Intelligently

OMC path




This parameter indicates whether the CE is evaluated during the decision of the cell

load based intelligent carrier power off. If its value is 0, the CE will be evaluated

during the decision. If its value is 1, the CE will not be evaluated during the decision.

4.1.2.25 Indication of Whether the Frequency Switch Off is Allowed or not

OMC path




This parameter indicates whether the carrier power off is allowed. The carrier that is

used to provide continuous coverage is not allowed to be closed.

4.1.2.26 P-CPICH Power Down Step Size Used to Switch Off Frequency Intelligently

OMC path

GUI: Managed Element->UMTS Logical Function Configuration->UTRAN Cell->

Extended Info of UTRAN Cell


This parameter indicates the size of P-CPICH power down step used to power off

carrier intelligently. In order to avoid call drops of UEs due to fast decrease of

P-CPICH power, this step cannot be set too big.



4.1.2.27 Time Interval between Two Downgrade of P-CPICH Power Used to Switch

Off Frequency Intelligently

OMC path




This parameter indicates the time interval between two downgrade of P-CPICH

power used to power off carrier intelligently. This time must be long enough to

complete the cell reconfiguration and hand over UEs to other cells.

4.1.2.28 Times of Downgrade of P-CPICH Power with Equal Step Used to Switch off

Frequency Intelligently

OMC path




This parameter indicates the number of times that P-CPICH power is downgraded

with equal steps for intelligent carrier power off. After the PcpiPwrDnStepTm times

downgrade steps of P-CPICH power, the power is decreased to the lowest value

immediately.

4.1.2.29 Share Cover Indication

OMC path

GUI: Managed Element->UMTS Logical Function Configuration->UTRAN Cell

->Adjacent Relation Configuration->Neighbouring Cell




This parameter describes the relationship between the current cell and the

neighboring cell. The relationship between the neighboring cell and the current cell

may be “Neighbor”, “Overlap”, “Covers”, or “Contained in”.

4.1.2.30 P-CPICH Power

OMC path


Cell->UTRAN Cell


This parameter indicates the P-CPICH power of a cell.

5 Counters and Alarms

5.1 Counters List

Counter No. Description

313046 Ratio of successful CS RAB establishment

313073 Ratio of successful PS RAB establishment

313465 Success Rate of Intra-RNC Inter-Frequency Hard Handover

313249 Ratio of CS Call Drop

313294 Ratio of PS Call Drop

313020 Ratio of successful RRC connection establishment

C310464564 Intelligent Carrier Power Off Duration

C310464565 Number of Intelligent Carrier Power Off

5.2 Alarms List

This feature has no related alarm.



6 Glossary

C

CE Channel Element

CPICH Common Pilot Channel

D

DCH Dedicated Channel

H

HSDPA High Speed Downlink Packet Access

HSUPA High Speed Uplink Packet Access

R

RAN Radio Access Network

RNC Radio Network Controller

zte umts intelligent carrier power off or on feature guide_v8 5_201312

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