The document describes power control configuration and mechanisms in UMTS networks. It discusses power control models and parameters. Open-loop power control sets initial uplink and downlink transmit power levels. For uplink on PRACH, the UE calculates initial preamble power based on measured CPICH_RSCP and parameters in system information blocks including CPICH transmit power, UL interference level, and a constant value. Power is then ramped for preamble retransmissions and set for the message part.

1. Table of Contents
Chapter 1 Power Control..............................................................................................................1
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2. List of Figures
Figure 1.2Power control configuration model (1)........................................................................6
Figure 1.3Power control configuration model (2)........................................................................7
Figure 1.4Power control configuration model (3)........................................................................7
Figure 1.5Power control configuration model (4)........................................................................7
Figure 1.6Power control configuration model (5)........................................................................8
Figure 1.7Power control configuration model (6)........................................................................8
Figure 1.8Power control configuration model (7)........................................................................9
Figure 1.9Power control configuration model (8)........................................................................9
Figure 1.10PRACH preamble and message parts......................................................................10
Figure 1.11Uplink open-loop power control on PRACH............................................................11
Figure 1.12Downlink open-loop power control on the DPDCH................................................40
Figure 1.13Uplink inner-loop power control...............................................................................46
Figure 1.14Downlink inner-loop power control..........................................................................51
Figure 1.15Uplink outer-loop power control procedure............................................................57
Figure 1.16Downlink power balance...........................................................................................66
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3. List of Tables
Table 1.1NEs required for power control......................................................................................4
Table 1.2Product versions.............................................................................................................4
Table 15.1Outer-loop Power Control Parameters on RAB basis..............................................65
Table 16.1Commands for the reconfiguration on the RNC side...............................................71
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5. Chapter 1 Power Control
1.1 Summary of Updates
This section provides the update history of this manual and introduces the contents of
subsequent updates.
Manual Version Description
01 (2006-9-26) Modified the principles to adjust SIR target in case of multi-
service.
02 (2006-9-28) Add description to the Rate Matching.
1.2 Introduction
The WCDMA system is a self-interfered system. The most important way to restrain
system interference level is the power control, especially in the uplink direction.
Without power control, a single overpowered UE could block a whole cell.
1.2.1 Definition
The power control is performed by the UE or UTRAN to adjust and control the power
of transmit signals according to the changes of channel environment and the quality
of receive signals.
In the WCDMA system, the power control mechanism comprises the following parts:
 Open-loop power control: Applicable in UL and DL. It sets the initial uplink and
downlink transmit power. Open-loop power control is used on physical channels
such as PRACH, DPCH.
 Inner-loop power control: Applicable in UL and DL. It directly adjusts the uplink
and downlink transmit power using power control commands. The inner loop
power control is performed by each UE and NodeB with the frequency of 1500
times per second (1.5 kHz).
 Outer-loop power control: Applicable in UL and DL. It indirectly controls the
uplink and downlink transmit power by increasing or decreasing the target SIR
value.
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6.  DL power balance: It is used to reduce the downlink power drifting of a given
UE during soft handover.
1.2.2 Purpose
The purpose of power control is to adjust the uplink and downlink power to the
minimum while ensuring the QoS.
 In the uplink, if a UE near the NodeB has too large a transmit power, it may
cause great interference to other UEs on the edge of the cell or even block the
whole cell. This is called near-far effect. In that case, uplink power control is
needed.
 In the downlink, the system capacity is determined by the total required code
power for each connection. Therefore, it is necessary to keep the transmit power
at the lowest level while ensuring signal quality at the receiving end for each UE.
In that case, the downlink power control is needed.
 Power control can be used against shadow fading and fast fading.
 Power control can increase system capacity.
 Power control for power drifting can improve the soft handover performance in
the downlink.
1.2.3 Terms and Abbreviations
I. Terms
None.
II. Abbreviations
Abbreviation Full Spelling
3GPP 3rd Generation Partnership Project
AMR Adaptive MultiRate
BER Bit Error Rate
BLER Block Error Rate
CDMA Code Division Multiple Access
CPCH Common Packet Channel
CPICH Common Pilot Channel
DCH Dedicated Channel
DL Downlink
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7. Abbreviation Full Spelling
DPB Downlink Power Balance
DPCCH Dedicated Physical Control Channel
DPCH Dedicated Physical Channel
DPDCH Dedicated Physical Data Channel
FDD Frequency Division Duplex
FER Frame Error Rate
LMT Local Maintenance Terminal
MML Man-Machine Language
MRC Maximum Ratio Combining
OLPC Outer-Loop Power Control
PCA Power Control Algorithm
P-CPICH Primary Common Pilot Channel
PRACH Physical Random Access Channel
RAN Radio Access Network
RNC Radio Network Controller
RRC Radio Resource Control
RSCP Received Signal Code Power
RTWP Received Total Wideband Power
SHO Soft Handover
SIR Signal-Interference Ratio
SRNC Serving RNC
TFCI Transport Format Combination Indicator
TPC Transmit Power Control
UE User Equipment
UL Uplink
UMTS Universal Mobile Telecommunications System
UTRAN UMTS Terrestrial Radio Access Network
Uu Uu Interface
WCDMA Wideband CDMA
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8. 1.3 Availability
1.3.1 Involved Network Element
1.3.1 shows the Network Elements (NEs) required for power control.
Table 1.1NEs required for power control
UE NodeB RNC MSC Server MGW SGSN GGSN HLR
√ √ √ - - - - -
Note:
 - = NE not required
 √ = NE required
1.3.2 Software Release
1.3.2 describes the versions of the HUAWEI UMTS RAN products that support power
control.
Table 1.2Product versions
Product Version
RNC BSC6800 V100R002 and later releases
NodeB DBS3800 V100R006 and later releases
BTS3812A V100R002 and later releases
BTS3812E V100R002 and later releases
1.3.3 Miscellaneous
None.
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9. 1.4 Impact
1.4.1 On System Performance
Power control improves the system capacity and ensures the QoS.
1.4.2 On Other Features
None.
1.5 Restrictions
None.
1.6 Technical Description
Power control in the uplink and the downlink is different. UL power control and DL
power control are separately described.
1.6.1 Power Control Configuration Model
The configuration model for power control is as show in 1.6.1, 1.6.1, 1.6.1, 1.6.1,
1.6.1, 1.6.1, 1.6.1 and 1.6.1.
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10. RNC
RadioClass
GlobalParaClass RAB&SRBClass CellClass
FRC.Class PSCH.Class CELL.Class
CORRMALGOSWITCH.Class SSCH.Class PCPICH.Class
OLPC.Class BCH.Class PRACHBASIC.Class
DPB.Class FACH.Class PRACHUUPARAS.Class
TYPRABBASIC.Class SCCPCH.Class AICH.Class
TYPRAB.Class CHPWROFFSET.Class RACH.Class
TYPSRBBASIC.Class AICHPWROFFSET.Class PRACHTFC.Class
TYPSRB.Class PICHPWROFFSET.Class CELLCAC.Class
TYPSRBOLPC.Class CELLRLPWR.Class CELLSETUP.Class
TYPRABOLPC.Class CELLOLPC.Class
TYPSRBSEMISTATICTF.Class
TYPRABSEMISTATICTF.Class
Figure 1.2Power control configuration model (1)
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11. CELLCAC.Class FRC.Class
Max UL TX power of conversational service TFCI power offset
Max UL TX power of streaming service TPC power offset
Max UL TX power of interactive service Pilot power offset
Max UL TX power of background service Power control algorithm selection
RRC Proc DPDCH PC preamble length UL closed loop power control step size
RRC Proc SRB delay DL power control mode
HHO Proc DPDCH PC preamble length FDD DL power control step size
HHO Proc SRB delay Constant value configured by default
Initial power offset for SHO
Figure 1.3Power control configuration model (2)
CELLRLPWR.Class RACH.Clsass
RL Max DL TX power Max preamble loop
RL Min DL TX power Random back-off lower limit
Random back-off upper limit
Figure 1.4Power control configuration model (3)
PRACHTFC.Class CELLSETUP.Clsass
Power offset Power increase limit
ADD PRACHTFC DL power window average size
Gain Factor BetaD DL power control mode 1
Figure 1.5Power control configuration model (4)
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12. PICHPWROFFSET PRACHBASIC.Class
PRACHUUPARAS.Class
CHPWROFFSET.Class
AICHPWROFFSET.Class Power increase step
Max preamble retransmission
AICH power offset
Constant value for calculating initial TX power
PICH power offset
Figure 1.6Power control configuration model (5)
TYPRABOLPC.Class DPB.Class
TYPSRBOLPC.Class DPB measurement report period
DPB measurement filter coefficient
BLER target value
DPB triggering threshold
SIR adjustment step
DPB stop threshold
Maximum SIR increase step
Ratio for max power
Maximum SIR decrease step
DPB adjustment ratio
Maximum SIR target
DPB adjustment period
Minimum SIR target
Max DPB adjustment step
Figure 1.7Power control configuration model (6)
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13. TYPRAB.Class BCH.Class
TYPRABBASIC.Class PSCH.Class
TYPSRB.Class PCPICH.Class
TYPSRBBASIC.Class
CELL.Class
Reference BetaC
Reference BetaD PCPICH transmit power
AICH.Class PSCH transmit power
AICH transmission timing BCH transmit power
TYPRABSEMISTATICTF.Class TYPSRBSEMISTATICTF.Class
UL rate matching attribute DL rate matching attribute
Figure 1.8Power control configuration model (7)
SSCH CELL.Class FACH.Class
SSCH transmit power PCH.Class
SCCPCH.Class
CELLSELRESEL.Class
PCH power
Max allowed UE UL TX power
Max transmit power of FACH
CORRMALGOSWITCH.Class
Power control algorithm switch OLPC.Class
CELLOLPC.Class
TYPSRBOLPC.Class
SIR init target value SIR measurement filter coefficient
OLPC adjustment period SIR adjustment coefficient
Figure 1.9Power control configuration model (8)
1.6.2 Open-Loop Power Control
Based on the measurement acquirement of receive power, open-loop power control
attempts to make a rough estimation of path loss by means of a downlink signal, and
then to provide a coarse initial power setting of the UE and the NodeB at the
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14. beginning of a connection.
I. Uplink Open-Loop Power Control
1) Uplink Open-Loop Power Control on PRACH
The PRACH random access process is comprised of two different parts that the UE
will send to the system: preamble part and message part.
AICH access
slots RX at UE
One access slot
Acq.
Ind.
τ
PRACH access
slots TX at UE
p-a
Pre- Pre-
amble amble Message part
τp-p τp-m
Figure 1.10PRACH preamble and message parts
The preamble part is at the length of 4096 chips and consists of 256 repetitions of a
signature that is 16–chip long. There are a maximum of 16 signatures available.
The message part is 10 or 20 ms long and is comprised of a control part and a data
part. The data and control parts are transmitted in parallel. Once the UE receives an
answer on the corresponding AICH, it will send the message part of the PRACH.
Therefore, the parameters related to the UE access on the PRACH involve three
parts:
 Initial power calculation for the first preamble
 Power ramping for preamble retransmission
 Power setting for message part
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15. 1 Initial Power Calculation for the First Preamble
To determine the initial power of the UE on its first PRACH preamble transmission,
both UE and UTRAN are involved, as shown in 1.
BCH :
•CPICH channel power
• UL interference level
RACH
•Measure CPICH_RSCP
•Determine the initial transmitted power
Figure 1.11Uplink open-loop power control on PRACH
Prior to PRACH transmission, the UE shall acquire the System Information Block
(SIB) that includes "Primary CPICH Tx power", “UL interference”, and “Constant
value”.
The UE measures the value for the CPICH_RSCP and calculates the initial power for
the first PRACH preamble with the following formula:
Preamble_Initial_Power (PRACH) = PCPICH TRANSMIT POWER - CPICH_RSCP +
UL interference + CONSTANT VALUE FOR CALCULATING INITIAL TX POWER
Where:
 The PCPICH TRANSMIT POWER parameter defines the PCPICH transmit
power in a cell. It is broadcast in SIB 5.
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16. Parameter name PCPICH transmit power
Parameter ID PCPICHPOWER
GUI range -100–500
Physical range& unit -10–50, step: 0.1 (dBm)
Default value 330
Optional / Optional
Mandatory
MML command ADD PCPICH/ MOD CELL
Description:
This parameter should be set based on the actual system environment such as cell
coverage (radius) and geographical environment. For the cells to be covered, the
downlink coverage should be guaranteed as a premise. For the cells requiring soft
handover area, this parameter should satisfy the proportion of soft handover areas
stipulated in the network planning. If the maximum transmit power of the PCPICH
is configured too great, the cell capacity will be decreased because a lot of system
resources will be occupied and the interference with the downlink traffic channels
will be increased.
Recommendation:
PCPICH TRANSMIT POWER is related to the downlink coverage in the network
planning. The default setting is 330, namely 33 dBm. If this parameter is too small,
it will influence directly the downlink pilot coverage range; if it is too big, the
downlink interference will increase, and the transmit power that can be distributed
to the services will be reduced, which will affect the downlink capacity. Meanwhile,
the configuration of this parameter also has influence on the distribution of
handover areas.
 CPICH_RSCP is the received signal code power, the received power on one
code measured on the primary CPICH. It is measured by the UE.
 UL interference is the UL RTWP measured by the NodeB, including noise
generated in the receiver, within the bandwidth defined by the receiver pulse
shaping filter. It is broadcast in SIB 7.
 The CONSTANT VALUE FOR CALCULATING INITIAL TX POWER parameter
compensates for the RACH processing gain. It is broadcast in SIB 5.
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17. Parameter name Constant value for calculating initial TX power
Parameter ID CONSTANTVALUE
GUI range -35–-10.
Physical range& unit dB
Default value -20
Optional / Mandatory Optional
MML command ADD PRACHBASIC/MOD PRACHUUPARAS
Description:
It is used to calculate the transmit power of the first preamble in the random access
process.
2 Power Ramping for Preamble Retransmission
If no positive or negative acquisition indicator on AICH is received by the UE from the
network after a given period, then the UE shall increase the preamble power by
POWER INCREASE STEP so that the Node-B can detect it, and re-send the
preamble. This “ramping up” process is characterized below:
 AICH transmission timing: In order to avoid too many collisions and consider the
processing capability of NodeB, it is specified in 3GPP that a UE shall wait at
least 3 or 4 access slots between the transmissions of 2 consecutive preambles,
according to the parameter AICH TRANSMISSION TIMING.
 Power increment step: Each time the UE re-transmits a preamble, the transmit
power is increased by POWER INCREASE STEP, compared to the previous
transmitted preamble.
 Maximum number of transmitted preambles: This limitation is defined by MAX
PREAMBLE RETRANSMISSION and MAX PREAMBLE LOOP parameters.
MAX PREAMBLE RETRANSMISSION defines the maximum number of
transmitted preambles allowed within an access cycle, and MAX PREAMBLE
LOOP defines the maximum number of random access preamble cycles. An
access cycle is defined by a number of radio frames on which the PRACH
access (and therefore a preamble ramping cycle) is allowed on specific slot
numbers.
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18. Parameter name AICH transmission timing
Parameter ID AICHTXTIMING
GUI range 0–1
Physical range& unit None
Default value 1
Optional / Mandatory Optional
MML command ADD AICH
Description:
The transmission timing information of an AICH. "0" indicates that there are 7680
chips offset between the access preamble of the PRACH and AICH; "1" indicates
that there are 12800 chips offset between them.
Caution:
In order to change the value of the AICH TRANSMISSION TIMING parameter, the
cell shall be firstly de-activated through DEA CELL.
After the old configuration of AICH is deleted through RMV AICH, a new AICH can be
established through ADD AICH.
Parameter name Power increase step
Parameter ID POWERRAMPSTEP
GUI range 1–8
Physical range& unit dB
Default value 2
Optional / Mandatory Optional
MML command ADD PRACHBASIC/MOD PRACHUUPARAS
Description:
The power increase step of the random access preambles transmitted before the
UE receives the acquisition indicator in the random access process.
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19. Recommendation:
If the value of POWER INCREASE STEP is too big, the access process will be
shortened, but the probability of wasting power will be bigger; if it is too small, the
access process will be lengthened, but transmitting power will be saved. It is a
value to be weighed.
Parameter name Max preamble retransmission
Parameter ID PREAMBLERETRANSMAX
GUI range 1–64
Physical range& unit None
Default value 20
Optional / Mandatory Optional
MML command ADD PRACHBASIC/MOD PRACHUUPARAS
Description:
The maximum number of preambles transmitted in a preamble ramping cycle.
Recommendation:
The product of the MAX PREAMBLE RETRANSMISSION parameter and the
above-mentioned PRACH POWER INCREASE STEP determines the maximum
ramp power of the UE within a preamble ramp cycle.
If this value is too small, the preamble power may fail to ramp to the required
value, resulting in UE access failure; if it is too big, the UE may repeatedly increase
the power and make access attempts, resulting in interference to other users.
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20. Parameter name Max preamble loop
Parameter ID MMAX
GUI range 1–32
Physical range& unit None
Default value 8
Optional / Mandatory Optional
MML command ADD RACH/MOD RACH
Description:
The maximum number of random access preamble loops.
Caution:
In order to change the value of the MAX PREAMBLE LOOP parameter, if the current
cell is on-going and there is one and only one PRACH in this cell, the cell shall be
firstly de-activated through DEA CELL.
The ramping process stops until the number of transmitted preambles has reached
the MAX PREAMBLE RETRANSMISSION within an access cycle, or when the
maximum number of access cycles MAX PREAMBLE LOOP is reached.
When a negative acquisition indicator on AICH is received by the UE, which indicates
rejection of the preamble, the UE shall wait for a certain back-off delay and re-initiate
a new random access process. Two parameters RANDOM BACK-OFF LOWER
LIMIT and RANDOM BACK-OFF UPPER LIMIT are defined respectively as the lower
and upper bounds of the random access back-off delay.
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21. Parameter name Random back-off lower limit
Parameter ID NB01MIN
GUI range 0–50
Physical range& unit None
Default value 0
Optional / Mandatory Optional
MML command ADD RACH/MOD RACH
Description:
The lower limit of random access back-off delay.
Parameter name Random back-off upper limit
Parameter ID NB01MAX
GUI range 0–50
Physical range& unit None
Default value 0
Optional / Mandatory Optional
MML command ADD RACH/MOD RACH
Description:
The upper limit of random access back-off delay.
Configuration Rule and Restriction:
RANDOM BACK-OFF LOWER LIMIT shall not be set bigger than RANDOM
BACK-OFF UPPER LIMIT.
If RANDOM BACK-OFF LOWER LIMIT = RANDOM BACK-OFF UPPER LIMIT, it
means that the retransmission periodicity of preamble part is fixed.
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22. Caution:
In order to change the value of the RANDOM BACK-OFF LOWER LIMIT or
RANDOM BACK-OFF UPPER LIMIT parameter, if the current cell is on-going and
there is one and only one PRACH in this cell, the cell shall be firstly de-activated
through DEA CELL.
3 Power Setting for Message Part
When the UE has received a positive acquisition indicator on AICH, it will transmit the
random access message using three or four uplink access slots after the uplink
access slot of the last transmitted preamble, depending on the AICH transmission
timing parameter. This message is made up of a control part and a data part:
 Control part: The transmit power of the control part of the random access
message should be POWER OFFSET higher than the power of the last
transmitted preamble.
Parameter name Power offset
Parameter ID POWEROFFSETPPM
GUI range -5–10
Physical range& unit dB
Default value Values according to PRACH TFC
Optional / Mandatory
Mandatory
MML command ADD PRACHTFC
Description:
The power offset between the last access preamble and the message control part.
The power of the message control part can be obtained by adding the offset to the
access preamble power.
Configuration Rule and Restriction:
POWER OFFSET must be set for each instance of PRACH TFC.
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23. Recommendation:
It is recommended that the value of POWER OFFSET corresponding to the TFC
for signaling transmission is set to -3 dB, and that corresponding to the TFC for
service transmission is set to -2 dB.
If the value of POWER OFFSET is set too low, it is likely that the signaling or the
service data carried over the RACH can not be correctly received, which affects
the uplink coverage. If the value is set too high, the uplink interference is
increased, and the uplink capacity is affected.
Caution:
In order to change the value of the POWER OFFSET parameter, if the current cell is
on-going and there is one and only one PRACH in this cell, the cell shall be firstly de-
activated through DEA CELL.
 Data part: The message part of the uplink PRACH channel employs gain factors
to control the control/data part:
a) GAIN FACTOR BETAC (βc) is the gain factor for the control part.
b) GAIN FACTOR BETAD (βd) is the gain factor for the data part.
Parameter name Gain Factor BetaC
Parameter ID GAINFACTORBETAC
GUI range 1–15
Physical range& unit None
Default value None
Optional / Mandatory Mandatory
MML command ADD PRACHTFC
Description:
The power occupancy factor of the control part.
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24. Parameter name Gain Factor BetaD
Parameter ID GAINFACTORBETAD
GUI range 1–15
Physical range& unit None
Default value None
Optional / Optional
Mandatory
MML command ADD PRACHTFC
Description:
The power occupancy factor of the data part.
PRACH CTFC POWER OFFSET GAIN FACTOR GAIN FACTOR
BETAC BETAD
0 -3 13 15
1 -2 10 15
Configuration Rule and Restriction:
Either Gain Factor BetaC or Gain Factor BetaD must be set to 15 for each
instance of power difference between control and data part of PRACH.
Caution:
In order to change the value of the GAIN FACTOR BETAC or GAIN FACTOR
BETAD parameter, if the current cell is on-going and there is one and only one
PRACH in this cell, the cell shall be firstly de-activated through DEA CELL.
2) Uplink Open-Loop Power Control on DPCCH
The UL open-loop power control on dedicated channel aims to determine the initial
power of the first uplink DPCCH.
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25. When setting up the first DPCCH, the UE shall start the UL inner loop power control
at a power level and set the initial power of uplink DPCCH with the following formula:
DPCCH_Initial_Power = DPCCH_Power_Offset - CPICH_RSCP
Where:
 CPICH_RSCP is the received signal code power, the received power on one
code measured on the primary CPICH. It is a measurement performed by the
UE.
 DPCCH_Power_Offset is provided by the RNC to the UE via RRC signaling in
the “Uplink power control info” IE or in the “Uplink power control info short” IE.
These IEs are included in the RRC messages of the radio bearer setup,
reconfiguration and release, transport channel and physical channel
reconfiguration, RRC connection setup and re-establishment and in the
handover to UTRAN command. For Huawei, DPCCH_Power_Offset is calculated
with the following formula:
DPCCH_Power_Offset = PCPICH TRANSMIT POWER + UL interference +
CONSTANT VALUE CONFIGURED BY DEFAULT
Where:
 The PCPICH TRANSMIT POWER parameter defines the PCPICH transmit
power in a cell.
 UL interference is the UL RTWP measured by the NodeB.
 The CONSTANT VALUE CONFIGURED BY DEFAULT parameter reflects the
target Ec/No of the uplink DPCCH preamble.
Parameter name Constant value configured by default
Parameter ID DEFAULTCONSTANTVALUE
GUI range -35–-10
Physical range& unit dB
Default value -27
Optional / Optional
Mandatory
MML command SET FRC
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26. Description:
This parameter is used by the RNC to compute the DPCCH power offset which is
used by the UE to calculate the initial transmit power of UL DPCCH during the
open loop power control process.
1 Maximum Allowed UL Transmit Power
The maximum allowed UL transmit power defines the total maximum output power
allowed for the UE and depends on the desired type of service. The information will
be transmitted on the FACH, mapped on the S-CCPCH, to the UE in the RADIO
BEARER SETUP message of the RRC protocol during the call setup.
For Huawei, the MAX ALLOWED UE UL TX POWER parameter is the maximum
transmit power of the PRACH channel when the UE tries to access to the specified
cell.
Parameter name Max allowed UE UL TX power
Parameter ID MAXALLOWEDULTXPOWER
GUI range -50–33
Physical range& unit dBm
Default value 24
Optional / Optional
Mandatory
MML command ADD CELLSELRESEL; MOD CELLSELRESEL
Description:
The maximum allowed uplink power transmitted on RACH of a UE in the cell,
which is related to the network planning.
Configuration Rule and Restriction:
If the value of MAX ALLOWED UE UL TX POWER is higher than the UE
capability, the maximum transmission power is of course limited by the UE
capability.
The transmission power on the PRACH for preamble part and message part
cannot be higher than the MAX ALLOWED UE UL TX POWER parameter.
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27. In addition, there are four parameters (MAX UL TX POWER OF CONVERSATIONAL
SERVICE, MAX UL TX POWER OF STREAMING SERVICE, MAX UL TX POWER
OF INTERACTIVE SERVICE and MAX UL TX POWER OF BACKGROUND
SERVICE) which correspond to the maximum allowed transmit power of four classes
of services: conversational, streaming, interactive and background respectively.
Parameter name Max UL TX power of conversational service
Parameter ID MAXULTXPOWERFORCONV
GUI range -50–33
Physical range& unit dBm
Default value 24
Optional / Optional
Mandatory
MML command ADD CELLCAC; MOD CELLCAC
Description:
The maximum UL transmit power for conversational service in a specific cell. It is
based on the UL coverage requirement of the conversational service designed by
the network planning.
Parameter name Max UL TX power of streaming service
Parameter ID MAXULTXPOWERFORSTR
GUI range -50–33
Physical range& unit dBm
Default value 24
Optional / Mandatory Optional
MML command ADD CELLCAC; MOD CELLCAC
Description:
The maximum UL transmit power for streaming service in a specific cell. It is based
on the UL coverage requirement of the streaming service designed by the network
planning.
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28. Parameter name Max UL TX power of interactive service
Parameter ID MAXULTXPOWERFORINT
GUI range -50–33
Physical range& unit dBm
Default value 24
Optional / Mandatory Optional
MML command ADD CELLCAC; MOD CELLCAC
Description:
The maximum UL transmit power for interactive service in a specific cell. It is
based on the UL coverage requirement of the interactive service designed by the
network planning.
Parameter name Max UL TX power of background service
Parameter ID MAXULTXPOWERFORBAC
GUI range -50–33
Physical range& unit dBm
Default value 24
Optional / Mandatory Optional
MML command ADD CELLCAC; MOD CELLCAC
Description:
The maximum UL transmit power for background service in a specific cell. It is
based on the UL coverage requirement of the background service designed by the
network planning.
Recommendation:
The above four parameters define the maximum uplink transmit power when
transmitting the services in a cell.
The bigger these parameters are, the wider the coverage of the corresponding
services will be. When the downlink coverage is exceeded, the uplink coverage
and downlink coverage of the service will become unbalanced. If these parameters
are too small, the uplink coverage will probably be smaller than the downlink
coverage of the service. If there is no special requirement, use the default value.
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29. 2 Rate Matching
The purposes of rate matching are as follows:
 To enable a CCTrCH to multiplex data bits from multiple traffic sub-flows, the
system matches traffic rates to physical channel rates.
 To meet the different QoS requirements of various services, the system adjusts
the coding redundancy degree of each channel.
It is equivalent to changing the bit energy (Eb) of each channel and balancing the
power among different channels. This method improves power usage and
reduces interference. The higher the service QoS requirement is, the higher the
corresponding RMA value. According to the RMA value of each traffic channel,
the rate matching mechanism repeats more bits of the services with higher QoS
requirements. Comparatively, it repeats less, even deletes some bits of the
services with lower QoS requirement. Thus, it meets different QoS requirements
through adjusting the bit redundancy degree of each transport channel.
Parameter name UL rate matching attribute
Parameter ID ULRATEMATCHINGATTR
GUI range 1–256
Physical range& unit None
Default value Values according to SRB and RAB
Optional / Mandatory Mandatory
MML command ADD TYPSRBSEMISTATICTF/
MOD TYPSRBSEMISTATICTF/
ADD TYPRABSEMISTATICTF/
MOD TYPRABSEMISTATICTF/
Description:
Rate matching attribute (RMA) is a semi-static parameter provided by the upper
layer for each traffic channel according to QoS. It represents the weight of
processing (repeating or deleting) data bits on the corresponding transport channel
during rate matching. This parameter is valid in the case of multiplexing of
transport channel, that is, when multiple transport channels are combined into a
CCTrCH. It is used to compare with the RMA values of other multiplexing transport
channels.
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30. Parameter name DL rate matching attribute
Parameter ID DLRATEMATCHINGATTR
GUI range 1–256
Physical range& unit None
Default value Values according to SRB and RAB
Optional / Mandatory
Mandatory
MML command ADD TYPSRBSEMISTATICTF/
MOD TYPSRBSEMISTATICTF/
ADD TYPRABSEMISTATICTF/
MOD TYPRABSEMISTATICTF/
Description:
Rate matching attribute (RMA) is a semi-static parameter provided by the upper
layer for each traffic channel according to QoS. It represents the weight of
processing (repeating or deleting) data bits on the corresponding transport channel
during rate matching. This parameter is valid in the case of multiplexing of
transport channel, that is, when multiple transport channels are combined into a
CCTrCH. It is used to compare with the RMA values of other multiplexing transport
channels.
Rate matching attribute parameters are defined per RAB in the following table:
Typical Services ULRATEMATCHI DLRATEMATCHI
NGATTR NGATTR
CS Domain RAB
12.2bps AMR 137:130:161 137:130:161
64kbps Conversational / Unknown 110 110
56kbps Conversational / Unknown 100 100
32kbps Conversational / Unknown 100 100
28.8kbps Conversational / Unknown 100 100
57.6kbps Streaming 100 100
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31. Typical Services ULRATEMATCHI DLRATEMATCHI
NGATTR NGATTR
PS Domain RAB
64kbps Conversational / Unknown 100 100
32kbps Conversational / Unknown 100 100
16kbps Conversational / Unknown 120 120
8kbps Conversational / Unknown 140 140
256kbps Streaming 100 100
144kbps Streaming 100 100
128kbps Streaming 100 100
64kbps Streaming 100 100
32kbps Streaming 100 100
16kbps Streaming 120 120
8kbps Streaming 140 140
384kbps Background 100 100
256kbps Background 100 100
144kbps Background 100 100
128kbps Background 100 100
64kbps Background 100 100
32kbps Background 100 100
16kbps Background 120 120
8 kbps Background 140 140
384kbps Interactive 100 100
256kbps Interactive 100 100
144kbps Interactive 100 100
128kbps Interactive 100 100
64kbps Interactive 100 100
32kbps Interactive 100 100
16kbps Interactive 120 120
8 kbps Interactive 140 140
Signaling RB
3.4kbps SRB 180 180
13.6kbps SRB 180 180
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32. 3 Power Difference Between DPCCH And DPDCH
The uplink DPCCH and DPDCH(s) are transmitted on different codes. In order to
meet a given QoS requirement on the transport channels whatever the transport
format they use, various power differences between DPDCH and DPCCH are defined
through gain factors, called βc for DPCCH and βd for DPDCH.
There are two ways of controlling the gain factors of the DPCCH code and the
DPDCH codes for different TFCs in normal (non-compressed) frames:
− βc and βd are signalled for the TFC, or
− βc and βd is computed for the TFC, based on the signalled settings for a
reference TFC.
3GPP allows combinations of these two methods to be used to associate βc and βd
values with all TFCs in the TFCS. These two methods are described in subsections
5.1.2.5.2 and 5.1.2.5.3 respectively of TS25.214. Several reference TFCs may be
signaled from higher layers.
For Huawei, a mix of these techniques is effectively applied, which requires the RNC
to compute and signal all TFC offsets when required. The RNC computes a new
power offset for each required TFC dynamically using a single set of configurable
reference values (corresponding to parameters Reference BetaC and Reference
BetaD) stored for each pre-defined RABs or SRBs. This computed TFC specific offset
is then signaled to the UE.
Parameter name Reference BetaC
Parameter ID BETAC
GUI range 1–15
Physical range& unit None
Default value Values according to SRB and RAB
Optional / Mandatory Mandatory
MML command ADD TYPSRBBASIC/MOD TYPSRB/ADD
TYPRABBASIC/MOD TYPRAB
Description:
Power occupation ratio of the control part of reference TFC.
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33. Parameter name Reference BetaD
Parameter ID BETAD
GUI range 1–15
Physical range& unit None
Default value Values according to SRB and RAB
Optional / Mandatory Mandatory
MML command ADD TYPSRBBASIC/MOD TYPSRB/ADD
TYPRABBASIC/ MOD TYPRAB
Description:
Power occupation ratio of the data part of reference TFC.
UL reference power offset parameters (βc,ref and βd,ref) are defined in the following
table:
Typical Services β c,ref : β d,ref
CS Domain RAB
12.2bps AMR 12:15
64kbps Conversational / Unknown 6:15
56kbps Conversational / Unknown 6:15
32kbps Conversational / Unknown 9:15
28.8kbps Conversational / Unknown 13:15
57.6kbps Streaming 7:15
PS Domain RAB
64kbps Conversational / Unknown 7:15
32kbps Conversational / Unknown 9:15
16kbps Conversational / Unknown 14:15
8kbps Conversational / Unknown 15:11
256kbps Streaming 4:15
144kbps Streaming 5:15
128kbps Streaming 5:15
64kbps Streaming 7:15
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34. Typical Services β c,ref : β d,ref
32kbps Streaming 9:15
16kbps Streaming 14:15
8kbps Streaming 15:11
384kbps Background 4:15
256kbps Background 4:15
144kbps Background 5:15
128kbps Background 5:15
64kbps Background 7:15
32kbps Background 9:15
16kbps Background 14:15
8 kbps Background 15:11
384kbps Interactive 4:15
256kbps Interactive 4:15
144kbps Interactive 5:15
128kbps Interactive 5:15
64kbps Interactive 7:15
32kbps Interactive 9:15
16kbps Interactive 14:15
8 kbps Interactive 15:11
Signaling RB
3.4kbps SRB 15:12
13.6kbps SRB 12:15
Configuration Rule and Restriction:
Either Reference BetaC or Reference BetaD must be set to 15 for each instance
of UL reference power offset.
The gain factors (βc and βd) are computed for certain TFCs, based on the settings for
a reference TFC with the formula defined in subsection 5.1.2.5.3 of TS25.214.
In Huawei implementation, in the case of RAB combination, the radio bearer specific
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35. reference values to be used are those belonging to the radio bearer whose maximum
rate TF has the highest bit rate of the radio bearers being combined. For example, for
the combination of the 3.4 kbps SRB service, 384 kbps background service, and 12.2
kbps AMR service, the reference power offset values applied are those belonging to
the maximum rate TF (12x336) of 384 kbps background radio bearer.
4 First Radio Link Establishment
When commanded by higher layers, the TPC commands sent on a downlink radio link
from NodeBs that have not yet achieved uplink synchronization will follow a pattern as
follows:
If the radio link is part of the first radio link set sent to the UE and if the value "n"
obtained from the parameter DL POWER CONTROL MODE 1 is different from 0,
then:
 The TPC pattern shall consist of n instances of the pair of TPC commands ("0",
"1"), followed by one instance of TPC command "1", where ("0","1") indicates
the TPC commands to be transmitted in two consecutive slots.
 The TPC pattern continuously repeat but shall be forcibly re-started at the
beginning of each frame where CFN mod 4 = 0.
In addition,
 The TPC pattern shall consist of only TPC commands "1".
 The TPC pattern shall terminate when uplink synchronization is achieved.
Parameter name DL power control mode 1
Parameter ID DLTPCPATTERN01COUNT
GUI range 0–30
Physical range& unit None
Default value 10
Optional / Mandatory Optional
MML command ADD CELLSETUP/MOD CELLSETUP
Description:
DL transmit power control (TPC) mode of the first radio link set before completion
of UL synchronization.
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36. Caution:
In order to change the value of the DL POWER CONTROL MODE 1 parameter
through MOD CELLSETUP, the cell shall be firstly de-activated through DEA CELL.
5 Transmit Power Control in the UL DPCCH Power Control Preamble
An uplink DPCCH Power Control Preamble (PC Preamble) is a period of uplink
DPCCH transmission prior to the start of the uplink DPDCH transmission in order to
ensure that the inner loop power control has converged when the transmission of the
data bits begins. It consists of a given number of DPCCH slots transmitted prior to the
data transmission on DPDCH. The RNC transmits the PC Preamble parameter
(number of DPCCH preamble slots) in the “Uplink DPCH power control info” IE using
the RRC signaling.
In addition to the PC Preamble delay, the mobile will not send any data on signaling
radio bearers during the number of frames indicated in the “SRB delay” IE, sent
through RRC signaling in the “Uplink DPCH power control info” IE.
Considering the application scenarios, different values for PC Preamble and SRB
delay parameters are configured.
 In the case of RRC connection establishment, PC Preamble and SRB delay are
respectively defined by parameters RRC PROC DPDCH PC PREAMBLE
LENGTH and RRC PROC SRB DELAY.
 In the case of hard handover, PC Preamble and SRB delay are respectively
defined by parameters HHO PROC DPDCH PC PREAMBLE LENGTH and
HHO PROC SRB DELAY.
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37. Parameter name RRC Proc DPDCH PC preamble length
Parameter ID RRCPROCPCPREAMBLE
GUI range 0–7
Physical range& unit Frame
Default value 0
Optional / Mandatory Optional
MML command ADD CELLCAC/MOD CELLCAC
Description:
DPDCH power control preamble length in DCH RRC process.
Parameter name RRC Proc SRB delay
Parameter ID RRCPROCSRBDELAY
GUI range 0–7
Physical range& unit Frame
Default value 7
Optional / Mandatory Optional
MML command ADD CELLCAC/MOD CELLCAC
Description:
Delay of SRB in DCH RRC process.
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38. Parameter name HHO Proc DPDCH PC preamble length
Parameter ID HHOPROCPCPREAMBLE
GUI range 0–7
Physical range& unit Frame
Default value 0
Optional / Mandatory Optional
MML command ADD CELLCAC/MOD CELLCAC
Description:
DPDCH power control preamble length in DCH HHO process.
Parameter name HHO Proc SRB delay
Parameter ID HHOPROCSRBDELAY
GUI range 0–7
Physical range& unit Frame.
Default value 7
Optional / Mandatory Optional
MML command ADD CELLCAC/MOD CELLCAC
Description:
Delay of SRB in DCH HHO process.
Inner loop power control is thus applied on the DPCCH only, in a first time, starting
from the initial DPCCH transmit power determined by the open loop power control
process. Then, once PC Preamble DPCCH slots have been transmitted and SRB
delay slots passed, data starts to be transmitted on the DPDCH at an initial transmit
power deduced from the current DPCCH transmit power and DPDCH/DPCCH power
difference (using βc and βd gain factors).
II. Downlink Open-Loop Power Control
1) Downlink Open-Loop Power Control on Common Channel
For the common channels, DL open-loop power control is to determine how much
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39. power is allocated to the PCPICH, P-SCH, S-SCH, P-CCPCH, S-CCPCH, AICH, and
PICH channels.
As mentioned previously, the P-CPICH power is defined by the PCPICH TRANSMIT
POWER parameter as an absolute value in dBm. The power of all other common
channels is defined in relation with the PCPICH TRANSMIT POWER parameter.
The following tables describe which parameter is used to determine the power for
each common channel:
Parameter name PSCH transmit power
Parameter ID PSCHPOWER
GUI range -350–150
Physical range& unit -35–15, step: 0.1 (dB)
Default value -50
Optional / Mandatory Optional
MML command ADD PSCH/MOD CELL
Description:
The offset of the PSCH transmit power from the PCPICH transmit power in a cell.
Parameter name SSCH transmit power
Parameter ID SSCHPOWER
GUI range -350–150
Physical range& unit -35–15, step: 0.1(dB)
Default value -50
Optional / Mandatory Optional
MML command ADD SSCH/MOD CELL
Description:
The offset of the SSCH transmit power from the PCPICH transmit power in a cell
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40. Recommendation:
These two parameters (PSCH TRANSMIT POWER and SSCH TRANSMIT
POWER) can be adjusted through measurement in the actual environment so that
the transmit powers of the synchronization channels just satisfy the UE receiving
demodulation requirement. Specifically, when UEs receive signals at different
locations within the range of the cell, the transmit power should be just enough to
ensure that the UE can implement fast synchronization in most areas at the verge
of the cell. Neither P-SCH nor S-SCH has come through channel code spectrum
spread, so they produce more serious interference than other channels do,
especially for near–end users. Therefore, the value should not be too big.
Parameter name BCH transmit power
Parameter ID BCHPOWER
GUI range -350–150
Physical range& unit -35–15, step: 0.1(dB)
Default value -20
Optional / Mandatory Optional
MML command ADD BCH/MOD CELL
Description:
The offset of the BCH transmit power from the PCPICH transmit power in a cell.
Recommendation:
The BCH TRANSMIT POWER parameter can be adjusted and optimized through
measurement in the actual environment. When UEs receive signals at different
locations within the range of the cell, the transmit power should be just enough to
ensure the correct demodulation of the information carried on the channel in most
areas at the verge of the cell. This setting of this parameter should not be too big,
so as to avoid unnecessary waste of the transmit power.
If the setting of this parameter is too small, the user at the verge of the cell will fail
to receive the system information correctly, and the downlink common channel
coverage will be influenced, which will affect cell coverage; if the setting is too big,
other channels will be interfered, the power resources will be occupied, and
consequently the cell capacity will be influenced.
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41. Parameter name Max transmit power of FACH
Parameter ID MAXFACHPOWER
GUI range -350–150
Physical range& unit -35–15, step: 0.1(dB)
Default value 10
Optional / Optional
Mandatory
MML command ADD FACH/MOD SCCPCH
Description:
The offset between the FACH transmit power and PCPICH transmit power in a
cell.
Recommendation:
Set the maximum FACH transmit power to an appropriate value that is just enough
to ensure the target BLER.
If the setting of this parameter is too small, the UE at the cell verge will fail to
receive correctly the services and signaling borne over the FACH, resulting in
influence on the downlink common channel coverage and the cell coverage; if it is
too big, other channels will be interfered, the power resources will be occupied,
and consequently the cell capacity will be influenced.
Caution:
In order to change the value of the MAX TRANSMIT POWER OF FACH parameter if
the current cell is on-going and there is one and only one SCCPCH in this cell, or in
order to change the configuration of the SCCPCH with the smaller SCCPCH ID when
there are two SCCPCHs in this cell, the cell shall be firstly de-activated through DEA
CELL.
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42. Parameter name PCH power
Parameter ID PCHPOWER
GUI range -350–150
Physical range& unit -35–15, step: 0.1(dB)
Default value -20
Optional / Mandatory Optional
MML command ADD PCH/MOD SCCPCH
Description:
The offset between the PCH transmit power and PCPICH transmit power in a cell.
Recommendation:
The default value of the PCH POWER parameter is -20, namely -2 dB.
If this parameter is too small, the UE at the cell verge will fail to receive paging
messages correctly, and this will influence downlink common channel coverage
and cell coverage; if it is too big, other channels will be interfered, the downlink
transmit power will be occupied, and consequently the cell capacity will be
influenced.
Parameter name AICH power offset
Parameter ID AICHPOWEROFFSET
GUI range -22–5
Physical range& unit dB
Default value -6
Optional / Mandatory Optional
MML command ADD CHPWROFFSET/MOD AICHPWROFFSET
Description:
The difference between the transmit power of AICH and that of PCPICH.
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43. Recommendation:
The default value of the AICH POWER OFFSET parameter is -6, namely -6 dB.
An appropriate transmit power value should be set for AICH to ensure that all
users at cell verge can receive the access indication. However, to avoid waste of
the power, the setting of the transmit power should not be too big.
Parameter name PICH power offset
Parameter ID PICHPOWEROFFSET
GUI range -10–5
Physical range& unit dB
Default value -7
Optional / Mandatory Optional
MML command ADD CHPWROFFSET/MOD
PICHPWROFFSET
Description:
The difference between the transmit power of PICH and that of PCPICH.
Recommendation:
The default value of the PICH POWER OFFSET parameter is -7, namely -7 dB.
If this parameter is too small, the UE at the cell verge will fail to receive paging
messages correctly, which will probably result in mis–operation in reading PCH
channel and waste of the UE battery and affect the downlink common channel
coverage and the cell coverage; if it is too big, other channels will be interfered, the
power resources will be occupied, and consequently the cell capacity will be
influenced.
2) Downlink Open-Loop Power Control on Dedicated Channel (DPDCH)
The aim of the DL open-loop power control on DPDCH is to determine the transmit
power of the traffic (dedicated) channel based on the downlink measurement report of
the UE. Both UE and UTRAN shall take part in downlink open-loop power control on
the DPDCH, as shown in 2.
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44. DCH
RACH reports the measured value
Measure CPICH Ec/N0
Determine the downlink initial power control
Figure 1.12Downlink open-loop power control on the DPDCH
The following gives a formula to calculate the initial power of the DPDCH when a
traffic (dedicated) channel is set up:
 
R Eb  P 
Pinitial = × ( ) DL ×  CPICH
− αPTotal 
W N0  Ec 
 ( ) CPICH 
 N0 
Where:
 R is the requested data bit rate by the user.
 W is the chip rate.

(Eb / N0) DL is the Eb/No target to ensure the service quality. In Huawei
implementation, RNC searches for a value of Eb/No target dynamically using a
set of pre-defined values corresponding to the specific cell environment type,
code type, coding rate and BLER target. For detailed information, refer to the
Load Control.
 (Ec/N0)CPICH is the ratio of received energy per chip to noise spectral density of
CPICH received by UE.
 α is the orthogonality factor in the downlink. In the WCDMA system, orthogonal
codes are employed in the downlink to separate the users, and without any multi-
path propagation on the orthogonality remains when the Node B signal is
received by the mobile station. However, if there is sufficient delay spread in the
radio channel, part of the base station signals will be regarded as multiple
access interference by the mobile station. The orthogonality of 1 corresponds to
perfectly orthogonal users.
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45.  Note:
 In Huawei implementation, α in the above formula is set to 0.
 Ptotal is the carrier power measured at the NodeB and reported to the RNC.
1 Radio Link Reconfiguration Power Setting
When reconfiguring a radio link, the new physical channel may not have the same
power as the previous one (because of different SF, and so on). It is not specified,
however, in 3GPP protocol that the RNC can send a new initial power for the new
configuration in the RADIO_LINK_RECONFIGURATION_PREPARE message, which
provides the NodeBs with the new physical/transport channel configuration.
Thus, the NodeB will adjust the downlink power through the process of inner-loop
power control.
2 Initial Power Setting In Soft Handover
In order to prevent a waste of downlink power while adding a new leg in the active
set, a new adjustment for power of the new leg is used. Based on the above
calculation as used for the initial power of the DPDCH when a traffic (dedicated)
channel is set up, the power required by a new leg introduced in the active set shall
be decreased by an offset, which is defined by the INITIAL POWER OFFSET FOR
SHO parameter.
Parameter name Initial power offset for SHO
Parameter ID SHOINITPWRPO
GUI range 0–25
Physical range& unit dB
Default value 15
Optional / Mandatory Optional
MML command ADD CELLCAC/MOD CELLCAC
Description:
Initial DL power offset for a new added RL in SRNC.
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46. 3 Upper and Lower Limits of DL DPDCH Power
The downlink dedicated traffic channel is limited by an upper and lower limit for each
radio link. This limitation is set through the RL MAX DL TX POWER and RL MIN DL
TX POWER parameters. Both parameters are provided a value for the different data
rate of radio access bearers. So they correspond to a set of values rather than a
single value.
Parameter name RL Max DL TX power
Parameter ID RLMAXDLPWR
GUI range -350–150
Physical range& unit -35–15; step: 0.1(dB)
Default value Values according to data rate of RABs
Optional / Mandatory Mandatory
MML command ADD CELLRLPWR/MOD CELLRLPWR
Description:
The maximum downlink transmit power of radio link. This parameter should fulfill
the coverage requirement of the network planning, and the value is relative to
PCPICH transmit power.
Parameter name RL Min DL TX power
Parameter ID RLMINDLPWR
GUI range -350–150
Physical range& unit -35–15; step: 0.1(dB)
Default value Values according to data rate of RABs
Optional / Mandatory Mandatory
MML command ADD CELLRLPWR/MOD CELLRLPWR
Description:
The minimum downlink transmit power of radio link. This parameter should
consider the maximum downlink transmit power and the dynamic range of power
control, and the value is relative to PCPICH transmit power.
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47. Configuration Rule and Restriction:
The parameters RL MAX DL TX POWER and RL MIN DL TX POWER must verify
the following relationship:
RL MIN DL TX POWER ≤RL MAX DL TX POWER
Typical Services RL MAX DL TX POWER RL MIN DL TX POWER
CS Domain RAB
12.2bps -30 -180
28.8kbps -20 -170
32kbps -20 -170
57.6kbps -10 -160
64kbps 30 -120
PS Domain RAB
384kbps 40 -110
256kbps 20 -170
144kbps 0 -150
128kbps 0 -150
64kbps -20 -170
32kbps -40 -190
16kbps -60 -210
8kbps -80 -230
4 Power Difference between DPCCH and DPDCH
For the downlink DPCH, the relative transmit power offset between DPCCH fields and
DPDCHs is determined by the network. The TFCI, TPC and pilot fields of the DPCCH
are offsets related to the power of DPDCHs by PO1, PO2, and PO3 dB respectively.
The power offsets PO1, PO2 and PO3 are defined by the TFCI POWER OFFSET,
TPC POWER OFFSET, and PILOT POWER OFFSET parameters respectively.
These power offsets cannot be reconfigured during the connection. These offsets are
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48. radio link specific, which are identical for all TFC in the TFCS, whereas for the uplink
the gain factors are TFC-dependent.
Parameter name TFCI power offset
Parameter ID TFCIPO
GUI range 0–24
Physical range& unit 0–6; step: 0.25(dB)
Default value 0
Optional / Optional
Mandatory
MML command SET FRC
Description:
The offset of TFCI bit transmit power from data bit transmit power in each time slot
of radio frames on DL DPCH.
Parameter name TPC power offset
Parameter ID TPCPO
GUI range 0–24
Physical range& unit 0–6; step: 0.25(dB)
Default value 12
Optional / Mandatory Optional
MML command SET FRC
Description:
The offset of TPC bit transmit power from data bit transmit power in each time slot
of radio frames on DL DPCH.
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49. Parameter name Pilot power offset
Parameter ID PILOTPO
GUI range 0–24
Physical range& unit 0–6; step: 0.25(dB)
Default value 12
Optional / Mandatory Optional
MML command SET FRC
Description:
The offset of pilot bit transmit power from data bit transmit power in each time slot
of radio frames on DL DPCH.
The downlink transmit power control procedure controls simultaneously the power of
a DPCCH and its corresponding DPDCHs. The power control loop adjusts the power
of the DPCCH and DPDCHs with the same amount, that is to say, the relative power
difference between the DPCCH and the DPDCHs is not changed.
1.6.3 Inner-Loop Power Control
Inner-loop power control is also called fast closed-loop power control. It controls the
transmit power according to the information returned from the peer physical layer. The
UE and the NodeB can adjust the transmit power according to the RX SIR of the peer
end, to compensate the fading of radio links.
Inner-loop power control consists of uplink inner-loop power control and downlink
inner-loop power control, and they work separately.
I. Uplink Inner-Loop Power Control
Uplink inner-loop power control is used to control the power of the uplink radio links.
In fact, uplink inner-loop power control is executed on the DPCCH, and related
DPDCH transmit power is calculated from DPCCH transmit power according to
DPDCH/DPCCH power ratio (βd /βc). For details, refer to 1.6.2“Open-Loop Power
Control”.
The RNC sends the SIR target to the NodeB and then the NodeB compares the
estimated SIR with the SIR target of uplink DPCCH pilot symbol once every timeslot.
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50.  If the estimated SIR is greater than the SIR target, the NodeB sends a TPC
command “down” to the UE on the downlink DPCCH TPC field.
 Otherwise, the NodeB sends a TPC command "Up".
 Note:
 The "Up" command means TPC = 1 and the "Down" command means TPC = 0.

For the SIR = RSCP / ISCP * SF ,
 The Received Signal Code Power (RSCP) is unbiased measurement of the
received power on one code.
 The Interference Signal Code Power (ISCP) is the interference on the received
signal, and SF=the spreading factor used on the DPCCH.
SIR estimation and
compare with SIR target TPC
1500 Hz
SIR target
NodeB UE
Figure 1.13Uplink inner-loop power control
The following describes the uplink inner-loop power control:
1 Single Radio Link
It means that the UE will receive only one TPC in each slot. The NodeB will estimate
the SIR value and sends TPC to the UE according to the comparison between SIR
target and SIR estimated result.
If the estimated SIR is greater than the SIR target, the NodeB sends a TPC command
“down” to the UE on the downlink DPCCH TPC field. Otherwise, the NodeB sends a
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51. TPC command “up”, where the “up” command means TPC = 1 and the “down”
command means TPC = 0.
When the UE receives the TPC, UE will adjust uplink transmit power according to the
Power Control Algorithm (PCA).
There are two types of inner-loop PCA algorithm: PCA1 and PCA2. The RNC
configures the PCA algorithm based on the POWER CONTROL ALGORITHM
SELECTION parameter.
Parameter name Power control algorithm selection
Parameter ID PWRCTRLALG
GUI range ALGORITHM1, ALGORITHM2.
Physical range& unit None
Default value ALGORITHM1
Optional / Mandatory Optional
MML command SET FRC
Description:
This parameter is used to inform the UE of the method for translating the received
Transmit Power Control (TPC) commands. In other words, it is used to select UL
power control algorithm.
Configuration Rule and Restriction:
Huawei sets the POWER CONTROL ALGORITHM SELECTION parameter to
algorithm1 as default value for all power control configurations
PCA1: UE adjusts uplink transmit power for each slot; the step of PCA1 should be
1dB or 2dB by UL CLOSED LOOP POWER CONTROL STEP SIZE parameter.
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52. Parameter name UL closed loop power control step size
Parameter ID ULTPCSTEPSIZE
GUI range 1–2
Physical range& unit dB
Default value 1
Optional / Mandatory Optional
MML command SET FRC
Description:
The step size of the closed loop power control performed on UL DPCCH. This
parameter is mandatory when the parameter [Power control algorithm selection] is
set as "ALGORITHM1".
The following table lists the TPC command corresponding to the specific TPC at
PCA1 algorithm:
TPC TPC_cmd
0 -1
1 1
PCA2: The UE adjusts the uplink transmit power for each 5-slot cycle and the step is
1 dB fixedly.
The following table lists the TPC command corresponding to the specific TPC at
PCA2 algorithm:
TPC TPC_cmd
0,0,0,0,0 0,0,0,0,-1
1,1,1,1,1 0,0,0,0,1
Else 0,0,0,0,0
2 Softer Handover
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53. It means that the UE will receive more than one TPC in each slot, but all the TPCs are
the same from each cell which belongs to one NodeB.
The UE will combine the DL TPC by Maximum Ratio Combining (MRC) algorithm.
Therefore, other processing is the same as that in scenario1 (single radio link).
3 Soft handover
It means that the UE will receive more than one TPC in each slot, and all the TPCs
come from different NodeBs.
On the NodeB side, there are two phases to process power control during the soft
handover procedure:
 Uplink synchronization phase:
The NodeB should send durative TPC=1 to newly-added radio link before
successful synchronization.
 Multi-radio link phase:
Each NodeB and each cell will estimate the SIR
individually and the general TPC individually. Therefore,
the UE may receive different TPC from different RLS.
On the UE side, the UE will receive different TPCs from different RLS at the same
time. Therefore, the UE should combine all the TPCs which come from different
NodeBs to get TPC commands and adjust uplink transmit power according to the
combined TPC commands.
There is different UE TPC combination algorithm for PCA1 and PCA2.
 In case of PCA1
First, the UE shall conduct a soft symbol decision Wi on each of the power control
commands TPCi, where i = 1, 2, …, N (N is greater than 1 and is the number of TPC
commands from radio links of different radio link sets.) That may be the result of a first
phase of combination.
Finally, the UE derives a combined TPC command, TPC_cmd, as a function γ of all
the N soft symbol decisions Wi:
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54. - TPC_cmd = γ (W1, W2, … WN), where TPC_cmd can take the values 1 or -1.
The function γ shall fulfill the following criteria:
If the N TPCi commands are random and uncorrelated, with equal probability of being
transmitted as "0" or "1", the probability that the output of γ is equal to 1 shall be
greater than or equal to 1/(2N), and the probability that the output of γ is equal to -1
shall be greater than or equal to 0.5. Further, the output of γ shall equal 1 if the TPC
commands from all the radio link sets are reliably “1”, and the output of γ shall equal
-1 if a TPC command from any of the radio link sets is reliably “0”.
Then, after deriving a combined TPC_cmd, the UE will adjust uplink transmit power
as pre-defined power step which is configured by the RNC.
 In case of PCA2
The UE shall make a hard decision on the value of each TPCi, where i = 1, 2, …, N (N
is the number of TPC commands from radio links of different radio link sets.) That
may be the result of a first phase of combination.
The UE shall follow this procedure for 5 consecutive slots, resulting in N hard
decisions for each of the 5 slots. The sets of 5 slots shall be aligned to the frame
boundaries and there shall be no overlap between each set of 5 slots.
The value of TPC_cmd is zero for the first 4 slots. After 5 slots have elapsed, the UE
shall determine the value of TPC_cmd for the fifth slot in the following way:
The UE first determines one temporary TPC command, TPC_temp i, for each of the N
sets of 5 TPC commands as follows:
- If all 5 hard decisions within a set are "1", TPC_tempi = 1.
- If all 5 hard decisions within a set are "0", TPC_tempi = -1.
- Otherwise, TPC_tempi = 0.
Finally, the UE derives a combined TPC command for the fifth slot, TPC_cmd, as a
function γ of all N temporary power control commands TPC_tempi:
TPC_cmd (5th slot) = γ (TPC_temp1, TPC_temp2, …, TPC_tempN), where TPC_cmd
(5th slot) can take the values 1, 0 or –1, and γ is given by the following definition:
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55. TPC_cmd is set to -1 if any of TPC_temp1 to TPC_tempN are equal to -1.
N
1
Otherwise, TPC_cmd is set to 1 if
N
∑ TPC _ temp
i =1
i > 0.5 .
Otherwise, TPC_cmd is set to 0.
Then, after deriving a combined TPC_cmd, the UE will adjust uplink transmit power
as 1dB step.
I. Downlink Inner-Loop Power Control
Downlink inner-loop power control is used to control the power of the downlink DPCH.
The UE receives the SIR target from higher layers, estimates the downlink SIR from
the pilot symbols of the downlink DPCH, and compares this estimated SIR with the
SIR target.
 If the estimated SIR is greater than the SIR target, the UE sends a TPC
command "down" to the NodeB.
 Otherwise, the UE sends a TPC command “up”.
TPC
SIR estimation and
compare with SIR target
1500 Hz
SIR target
NodeB UE
Figure 1.14Downlink inner-loop power control
The following describes the downlink inner-loop power control:
1 Single Radio Link
The downlink power control can be classified into two modes.
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56. The UE shall check the downlink power control mode (DPC_MODE) before the TPC
command is generated:
 If DPC_MODE = 0,
The UE sends a unique TPC command in each slot and the TPC command
generated is transmitted in the first available TPC field in the uplink DPCCH.
 If DPC_MODE = 1,
The UE repeats the same TPC command over 3 slots and the new TPC
command is transmitted such that there is a new command at the beginning of
the frame.
The DPC_MODE parameter is a UE-specific parameter controlled by the UTRAN.
The DPC mode can be set by the DL POWER CONTROL MODE parameter.
Parameter name DL power control mode
Parameter ID DPCMODE
GUI range SINGLE_TPC, TPC_TRIPLET_IN_SOFT,
TPC_AUTO_ADJUST.
Physical range& unit None
Default value SINGLE_TPC
Optional / Mandatory Optional
MML command SET FRC
Description:
SIGNLE_TPC, a fast power control mode, indicates that a unique TPC command
is sent in each time slot on DPCCH. TPC_TRIPLET_IN_SOFT, a slow power
control mode, indicates that the same TPC command is sent in three time slots, it
is applicable to soft handover and it can decrease the power deviation.
TPC_AUTO_ADJUST, an automatically adjusted mode, indicates that the value of
DPC_MODE can be modified by sending the message "ACTIVE SET UPDATE" to
UE.
Configuration Rule and Restriction:
Huawei sets the DL POWER CONTROL MODE parameter to singel_TPC as
default value for all power control configurations
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57. Upon receiving the TPC commands, the UTRAN shall adjust its downlink
DPCCH/DPDCH power accordingly.
 If DPC_MODE = 0, the UTRAN shall estimate the transmitted TPC command
TPCest to be 0 or 1, and shall update the power every slot.
 If DPC_MODE = 1, the UTRAN shall estimate the transmitted TPC command
TPCest over three slots to be 0 or 1, and shall update the power every three slots.
After estimating the k:th TPC command, the UTRAN shall adjust the current downlink
power P(k-1) [dB] to a new power P(k) [dB] according to the following formula:
P(k) = P(k - 1) + PTPC(k) + Pbal(k)
Where:
 PTPC(k) is the k:th power adjustment due to the inner loop power control.
 Pbal(k) [dB] is a correction according to the downlink power control procedure for
balancing radio link powers towards a common reference power. For a single
radio link, Pbal equals 0.
 PTPC(k) is calculated according to the following:
– If the value of Limited Power Increase Used parameter is 'Not used', then,
+ Δ if TPC est ( k ) = 1
PTPC (k ) =  TPC , [dB]
− Δ TPC if TPC est (k ) = 0
The limited power increase used parameter could be set by the parameter of
INNER_LOOP_DL_LMTED_PWR_INC_SWITCH.
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58. Parameter name Power control algorithm switch
Parameter ID INNER_LOOP_DL_LMTED_PWR_INC_SWITCH
GUI range 1(ON), 0(OFF)
Physical range& unit None
Default value 0
Optional / Mandatory Optional
MML command SET CORRMALGOSWITCH
Description:
When it is checked, limited power increase algorithm is applied in the inner loop
power control.
– If the value of limited power increase used parameter is 'Used', then, the k:th
inner loop power adjustment shall be calculated through the following formula:
+ ∆ TPC if TPC est (k ) = 1 and ∆ sum (k ) + ∆ TPC < Power_Raise_Limit

PTPC (k ) =  0 if TPC est (k ) = 1 and ∆ sum (k ) + ∆ TPC ≥ Power_Raise_Limit , [dB]
− ∆ if TPC est ( k ) = 0
 TPC
The Power_Raise_Limit can be set by the POWER INCREASE LIMIT parameter.
Parameter name Power increase limit
Parameter ID POWERRAISELIMIT
GUI range 0–10
Physical range& unit dB
Default value 10
Optional / Mandatory Optional
MML command ADD CELLSETUP/MOD CELLSETUP
Description:
The increase of DL transmit power within DlPowerAverageWindowSize cannot
exceed this parameter value.
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59. Caution:
In order to change the value of the POWER INCREASE LIMIT parameter through
MOD CELLSETUP, the cell shall be firstly de-activated through DEA CELL.
Where:
k−1
∆ (k ) =
sum
i= −
∑PTPC (i )
k DL_Power_Averaging_Window_Size
is the temporary sum of the last DL_Power_Averaging_Window_Size inner loop
power adjustments (in dB). DL_Power_Averaging_Window_Size can be set by the
DL POWER WINDOW AVERAGE SIZE parameter.
Parameter name DL power window average size
Parameter ID DLPOWERAVERAGEWINDOWSIZE
GUI range 1–60
Physical range& unit slot.
Default value 20
Optional / Mandatory Optional
MML command ADD CELLSETUP/MOD CELLSETUP
Description:
Content: UTRAN calculates the increase of DL transmit power within the period
defined via this parameter to determine whether the increase exceeds
PowerRaiseLimit. If so, UTRAN will not increase the power even when it receives
the command to raise the power.
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60. Caution:
In order to change the value of the DL POWER WINDOW AVERAGE SIZE
parameter through MOD CELLSETUP, the cell shall be firstly de-activated through
DEA CELL.
The power control step size TPC can be any of the four values of 0.5, 1, 1.5 and 2 dB
and be set by the FDD DL POWER CONTROL STEP parameter.
Parameter name FDD DL power control step size
Parameter ID FDDTPCDLSTEPSIZE
GUI range STEPSIZE_0.5DB, STEPSIZE_1DB, STEPSIZE_1.5DB,
STEPSIZE_2DB.
Physical range& unit 0.5, 1, 1.5, 2(dB)
Default value STEPSIZE_1DB
Optional / Mandatory Optional
MML command SET FRC
Description:
Content: The step size of the closed loop power control performed on DL DPCH in
Frequency Division Duplex (FDD) mode.
2 Scenario Softer Handover
In the case of softer handover, the NodeB gets one TPC after MRC combination.
Then the downlink power procedure is the same as that in single radio link.
3 Soft Handover
For details about the soft handover, refer to the description in the subsection
1.6.5“Downlink Power Balance”.
1.6.4 Outer-Loop Power Control
The aim of outer-loop power control is to maintain the communication quality at the
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61. level required by the service bearer through adjustment of the SIR target. This control
acts on each DCH belonging to the same RRC connection.
The SIR target needs to be adjusted when the UE speed or the multi-path
propagation environment changes, so that the communication quality can maintain
the same. If a fixed SIR target is selected, the resulting quality of the communication
might be too low or too high, which may cause an unnecessary power rise in most
situations.
I. Uplink Outer-Loop Power Control
The uplink quality is observed after macro diversity selection combining in the RNC.
Therefore, uplink outer-loop power control is performed in the SRNC.
The SRNC compares the RX BLER with the BLER target. If the RX BLER is greater
than the BLER target, the SRNC increases the SIR target; otherwise, decreases.
After adjusting the SIR target, the SRNC sends the new SIR target through FP frames
to all NodeBs for uplink inner loop power control.
BLER SIR measurement
measurement and comparing
and comparing
Outer loop Inner loop
BLER target
settting SIR target settting Sent TPC
UE
RNC
NodeB
Figure 1.15Uplink outer-loop power control procedure
The uplink outer-loop power control for all UEs can be deactivated by
OLPC_SWITCH; or by setting SIR ADJUSTMENT STEP to zero to deactivate uplink
outer loop power control for different services.
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62. Parameter name Power control algorithm switch
Parameter ID OLPC_SWITCH
GUI range 0, 1.
Physical range& unit OFF, ON (NONE)
Default value 1
Optional / Mandatory Optional
MML command SET CORRMALGOSWITCH
Description:
When it is ON, RNC will update the uplink SIR TARGET of RLs on the NODEB
side by IUB DCH FP signals.
1 Initial SIR Target Setting
The initial SIR target value is provided by the RNC to the NodeB through the SIR INIT
TARGET VALUE parameter which is service-dependent. This value is transmitted to
the NodeB using NBAP signaling at each RADIO LINK SETUP or RADIO LINK
RECONFIGURATION PREPARE.
Parameter name SIR init target value
Parameter ID INITSIRTARGET
GUI range 0–255
Physical range& unit -8.2–17.3; step: 0.1(dB)
Default value Refer to I.
Optional / Mandatory Mandatory
MML command ADD TYPSRBOLPC/MOD TYPSRBOLPC/ ADD
TYPRABOLPC/MOD TYPRABOLPC
Description:
This parameter defines the initial SIR target value of Outer Loop Power Control
algorithm. Value 0 corresponds to -8.2 dB, value 10 to -7.2 dB, and value 255 to
17.3 dB.
Configuration Rule and Restriction:
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63. For the same SRB or TRB, SIR INIT TARGET VALUE, MAXIMUM SIR TARGET
and MINIMUM SIR TARGET must verify the following relationship:
MINIMUM SIR TARGET ≤ SIR INIT TARGET VALUE ≤MAXIMUM SIR TARGET
2 SIR Target Adjustment
The outer-loop power control adjusts SIR target through a OLPC ADJUSTMENT
PERIOD parameter as follows:
BLERmeas ((n − 1), i ) − BLERtar (i )
SIRtar(n)＝MAX [ SIRtar (n − 1) + * Step(i ) * factor ]
BLERtar (i )
In the above formula, meanings of the parameters are as follows:
 i is the ith transmission channel.
 n is the nth adjustment period.
 SIRtar(n) is the SIR target used by the nth adjustment period which could be set
by parameter OLPC ADJUSTMENT PERIOD.
 MAX is the maximum value in the total i transmission channels.
 ErrTb( n，i)
BLERmeas(n,i) is the instantaneous BLER meas (n, i )＝ Tb(n，i) measured for the
ith transmission channel in the nth adjustment period.
- Tb(n,i) is the number of error blocks in the TBs received from the ith
transmission channel in the nth adjustment period.
- ErrTb(n,i) is the number of error blocks indicated by the CRCI in the Tb(n,i) that
is received from the ith transmission channel.
 BLERtar(i) is the BLER target of the ith transmission channel, which could be
set by parameter SERVICE DCH_BLER TARGET VALUE.
 Step(i) is the adjustment step of the ith transmission channel, which could be set
by parameter SIR ADJUSTMENT STEP.
 factor is the adjustment factor which could be set by parameter SIR
ADJUSTMENT COEFFICIENT.
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64. Parameter name OLPC adjustment period
Parameter ID SIRADJUSTPERIOD
GUI range 1–100
Physical range& unit 10–1000, step: 10(ms)
Default value Refer to I.
Optional / Mandatory
Mandatory
MML command ADD TYPSRBOLPC/MOD TYPSRBOLPC/ ADD
TYPRABOLPC/MOD TYPRABOLPC
Description:
Outer Loop Power Control varies with radio environment. A fast changing radio
environment leads to a shorter Outer Loop Power Control adjustment period, while
a slower changing one makes the period longer.
Parameter name SIR measurement filter coefficient
Parameter ID SIRMEASFILTERCOEF
GUI range D0, D1, D2, D3, D4, D5, D6, D7, D8, D9, D11, D13, D15,
D17, D19.
Physical range& unit 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 13, 15, 17, 19(NONE)
Default value D0
Optional / Mandatory Optional
MML command SET OLPC
Description:
The filter coefficient used for SIR measurement.
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65. Parameter name SIR adjustment coefficient
Parameter ID SIRADJUSTFACTOR
GUI range 1–10
Physical range& unit 0.1–1; step: 0.1(NONE)
Default value 10
Optional / Optional
Mandatory
MML command SET OLPC/ADD CELLOLPC/MOD CELLOLPC
Description:
It is used to adjust the best OLPC step when the OLPC algorithm is given.
Parameter name BLER target value
Parameter ID BLERQUALITY
GUI range -63–0
Physical range& unit 5*10^(-7) –1(NONE)
Default value Refer to I.
Optional / Mandatory
Mandatory
MML command ADD TYPSRBOLPC/MOD TYPSRBOLPC/ADD
TYPRABOLPC/MOD TYPRABOLPC
Description:
If signalling is carried over DCH, this parameter indicates the target transmission
quality of DCH, that is, DCH BLER target value at the radio interface. This
parameter is related to QoS and is used by the CRNC to determine the SIR target
for admission and power management. Use the formula below to get the
parameter integer value: 10*Log10(BLER).
Configuration Rule and Restriction:
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66. If the BLER TARGET VALUE parameter changes, the SIR ADJUSTMENT STEP
parameter should modify synchronously. For the same SRB or TRB, if the default
value of BLER TARGET VALUE and SIR ADJUSTMENT STEP are BLERquality1
and SirAdjustStep1, after change, the value of BLER TARGET VALUE and SIR
ADJUSTMENT STEP are BLERquality2 and SirAdjustStep2,
BLERquality1, SirAdjustStep1, BLERquality2, SirAdjustStep2 must verify the
following relationship:
(1-BLERquality1) * SirAdjustStep1/BLERquality1 = (1-BLERquality2) *
SirAdjustStep2/BLERquality2
Parameter name SIR adjustment step
Parameter ID SIRADJUSTSTEP
GUI range 0–10000
Physical range& unit 0–10, step: 0.001(dB)
Default value Refer to I.
Optional / Mandatory Mandatory
MML command ADD TYPSRBOLPC/MOD TYPSRBOLPC/ ADD
TYPRABOLPC/MOD TYPRABOLPC
Description:
Adjustment step of SIR target used by the outer loop power control algorithm.
The principles to adjust SIR target in case of multi-services are described as follows:
 The maximum value of SIR target among multiple services is used for the SIR
target adjustment.
 If one of the services requires increasing the SIR target, the maximum value is
used for the adjustment in the increase.
 Only when all the services require reducing the SIR target, the maximum value is
used for the adjustment in the decrease.
3 SIR target adjustment limitation
The service-dependent parameters MAXIMUM SIR INCREASE STEP and Maximum
SIR decrease step limit the changes to the SIR target during any adjustment.
Compute the quantity ∆SIRtar = SIRtar(n+1) – SIRtar(n):
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67.  If ( ∆SIRtar > 0 ) AND (∆SIRtar > “MAXIMUM SIR INCREASE STEP”)
Then SIRtar(n+1) = SIRtar(n) + MAXIMUM SIR INCREASE STEP
 If ( ∆SIRtar < 0 ) AND (ABS(∆SIRtar) > “MAXSIRSTEPDOWN”)
Then SIRtar(n+1) = SIRtar(n) –MAXSIRSTEPDOWN
Parameter name Maximum SIR increase step
Parameter ID MAXSIRSTEPUP
GUI range 0–10000
Physical range& unit 0–10, step: 0.001(dB)
Default value Refer to I.
Optional / Mandatory Mandatory
MML command ADD TYPRABOLPC/MOD TYPRABOLPC
Description:
Maximum allowed SIR step-up within an Outer Loop Power Control adjustment
period.
Parameter name Maximum SIR decrease step
Parameter ID MAXSIRSTEPDN
GUI range 0–10000
Physical range& unit 0–10, step: 0.001 (dB)
Default value Refer to I.
Optional / Mandatory Mandatory
MML command ADD TYPSRBOLPC/MOD TYPSRBOLPC/ADD
TYPRABOLPC/MOD TYPRABOLPC
Description:
Maximum allowed SIR step-down within an Outer Loop Power Control adjustment
period.
 SIR target limitation
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68. The service-dependent parameters MAXIMUM SIR TARGET and MINIMUM SIR
TARGET limit the SIR target during any adjustment.
Parameter name Maximum SIR target
Parameter ID MAXSIRTARGET
GUI range 0–255
Physical range& unit -8.2–17.3; step: 0.1(dB)
Default value Refer to I.
Optional / Mandatory Mandatory
MML command ADD TYPSRBOLPC/MOD TYPSRBOLPC/ ADD
TYPRABOLPC/MOD TYPRABOLPC
Description:
This parameter defines the initial SIR target value of Outer Loop Power Control
algorithm. Value 0 corresponds to -8.2 dB, value 10 to -7.2 dB, and value 255 to
17.3 dB.
Parameter name Minimum SIR target
Parameter ID MINSIRTARGET
GUI range 0–255
Physical range& unit -8.2–17.3; step: 0.1(dB)
Default value Refer to I.
Optional / Mandatory Mandatory
MML command ADD TYPSRBOLPC/MOD TYPSRBOLPC/ ADD
TYPRABOLPC/MOD TYPRABOLPC
Description:
This parameter defines the initial SIR target value of Outer Loop Power Control
algorithm. Value 0 corresponds to -8.2 dB, value 10 to -7.2 dB, and value 255 to
17.3 dB.
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69. Table 15.1Outer-loop Power Control Parameters on RAB basis
Service Service SIR init Maximu Minim OLPC SIR Maximu MaxSir
DCH_B target m SIR um adjust adjust m SIR StepDo
LER value target SIR ment ment increas wn
target target period step e step
value
SRB 3.4k -20 102 132 62 4 4 400 200
SRB -20 122 132 62 2 10 500 200
13.6k
AMR -20 102 132 62 2 5 500 200
12.2k
CSD 64k -27 122 152 62 2 2 1000 100
PS I/B 8k -20 102 132 62 4 4 400 200
PS I/B -20 102 132 62 2 4 400 200
16k
PS I/B -20 102 132 62 2 4 400 200
32k
PS I/B -20 102 132 62 2 4 400 200
64k
PS I/B -20 102 132 62 2 4 400 200
128k
PS I/B -20 107 137 62 2 4 400 200
144k
PS I/B -20 122 152 62 2 4 400 200
256k
PS I/B -20 142 172 62 2 4 400 200
384k
 Note:
 CSD: CS data services.
 I/B: Interactive and Background.
II. Downlink Outer-Loop Power Control
The downlink outer-loop power control is implemented in the UE. Therefore, this
algorithm is UE-manufacturer specific. The information signaled to the UE by the
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70. RNC is a quality target for each radio bearer, expressed as a BLER target. Then,
depending on the mobile-manufacturer specific outer-loop algorithm, an initial SIR
target value may be deduced from this BLER value and then regularly updated or not.
The BLER target quality is configurable per RAB, defined by SERVICE DCH_BLER
TARGET VALUE in I.
1.6.5 Downlink Power Balance
During soft handover, the UL TPC command is demodulated in each RLS and due to
demodulation errors, the DL transmit power of the each branch drift separately, which
causes loss to the macro-diversity gain.
During the softer handover, the difference between the initial transmit power of added
link and existing link may also cause the power drift. The DL Power Balance (DPB)
algorithm is introduced to reduce the power drift between links during the soft
handover and the softer handover.
RNC
NodeB
NodeB
UE
Figure 1.16Downlink power balance
The implementation of the DPB algorithm is as follows:
1) According to measurement control (the measurement parameters includes DPB
MEASUREMENT REPORT PERIOD, DPB MEASUREMENT FILTER
COEFFICIENT parameters) from the RNC, the NodeB periodically reports the
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71. TCP (transmit code power) of RL in soft/softer handover.
Parameter name DPB measurement report period
Parameter ID RPTPERIOD
GUI range 1–6000
Physical range& unit 10–60000; step: 10(ms)
Default value 70
Optional / Mandatory Optional
MML command SET DPB
Description:
The report period of downlink power measurement.
Parameter name DPB measurement filter coefficient
Parameter ID DPBMEASFILTERCOEF
GUI range D0, D1, D2, D3, D4, D5, D6, D7, D8, D9, D11, D13, D15,
D17, D19
Physical range& unit 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 13, 15, 17, 19(None)
Default value 0
Optional / Mandatory Optional
MML command SET DPB
Description:
The filter coefficient for the measured values in NodeB.
2) The RNC determines the power difference of RL for UE in softer status, if the
power difference is larger than DPB TRIGGERING THRESHOLD, and then
starts the power balance, if less than DPB STOP THRESHOLD, then stops the
power balancing; for UE in soft status, DPB is always triggered.
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72. Parameter name DPB triggering threshold
Parameter ID DPBSTARTTHD
GUI range 0–255
Physical range& unit 0–127.5; step: 0.5(dB)
Default value 8
Optional / Mandatory Optional
MML command SET DPB
Description:
The threshold of triggering DL power balancing in softer handover. When the
difference of the power values of every two paths is greater than or equal to this
threshold in softer handover, the RNC shall trigger DL power balancing; otherwise,
shall not.
Parameter name DPB stop threshold
Parameter ID DPBSTOPTHD
GUI range 0–255
Physical range& unit 0–127.5; step: 0.5.(dB)
Default value 4
Optional / Mandatory Optional
MML command SET DPB
Description:
The threshold of stopping DL power balancing in softer handover. When the
difference of the power values of every two paths is smaller than or equal to this
threshold in softer handover, the RNC shall stop DL power balancing; otherwise,
shall not.
3) After starting power balancing, the RNC calculates the UE DL reference power
Pref and sends the Pref to the NodeB by the DOWNLINK POWER CONTROL
REQUEST message:
Pref = (RATIO FOR MAX POWER) / 100 * (Pmax-Pcpich) + (1- RATIO FOR MAX
POWER / 100) * (Pmin - Pcpich)
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73. Where:
 Pmax is the maximum value in the UE’ s all RL DL TCP (transmit code power) ;
 Pmin is the minimum value in the UE’ s all RL DL TCP (transmit code power).
The DOWNLINK POWER CONTROL REQUEST message includes DPB
ADJUSTMENT RATIO, DPB ADJUSTMENT PERIOD, MAX DPB ADJUSTMENT
STEP parameters.
Parameter name Ratio for max power
Parameter ID RATIOFORMAXPOWER
GUI range 0–100
Physical range& unit 0–1; step: 0.01(None)
Default value 50
Optional / Optional
Mandatory
MML command SET DPB
Description:
The ratio of the maximum power in calculation of reference power for DPB.
Parameter name DPB adjustment ratio
Parameter ID ADJUSTRATIO
GUI range 0–100
Physical range& unit 0–1; step: 0.01
Default value 0
Optional / Mandatory Optional
MML command SET DPB
Description:
The adjustment ratio for DPB.
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74. Parameter name DPB adjustment period
Parameter ID ADJUSTPERIOD
GUI range 1–256
Physical range& unit frame
Default value 2
Optional / Mandatory Optional
MML command SET DPB
Description:
DPB adjustment period.
Parameter name Max DPB adjustment step
Parameter ID MAXADJUSTSTEP
GUI range 1–10
Physical range& unit slot
Default value 4
Optional / Mandatory Optional
MML command SET DPB
Description:
During downlink power adjustment, the maximum adjustment step should not
exceed 1dB within the slots specified by this parameter.
4) The NodeB calculates the power on each radio link according to the following
rule:
P(i) = P(i-1) + PTPC(i) + Pbal(i)
Where:
 P(i) is TCP of slot i and P(i-1) is TCP of slot i-1.
 PTPC(i) is the result of inner-loop power control.
 Pbal is a corrective term introduced by power balance.
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75. In one DPB ADJUSTMENT PERIOD, the total correction Pbal is defined as:
∑P bal =(1 −r )(Pref +PP −CPICH −Pinit )
Where, r is DPB ADJUSTMENT RATIO and Pinit is the current DL DPDCH power.
1.7 Capabilities
None.
1.8 Implementation
1.8.1 Enabling Power Control
This feature does not need extra hardware or initialization. It takes effect
automatically.
For the network planning or optimization, the data can be adjusted on the RNC LMT
as required.
1.8.2 Reconfiguring Power Control Parameters
I. Parameter Reconfiguration on the RNC Side
I describes the commands used for the reconfiguration on the RNC side.
Table 16.1Commands for the reconfiguration on the RNC side
Function Command
About the RNC- To query the RNC-oriented LST OLPC
oriented OLPC OLPC algorithm parameters
algorithm parameters
To set the RNC-oriented SET OLPC
OLPC algorithm parameters
About the cell- To add the cell-oriented OLPC ADD CELLOLPC
oriented OLPC algorithm parameters
algorithm parameters
To modify the cell-oriented MOD CELLOLPC
OLPC algorithm parameters
To remove the cell-oriented RMV CELLOLPC
OLPC algorithm parameters
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76. Function Command
About the DPB To query the DPB algorithm LST DPB
algorithm parameters parameters
To set the DPB algorithm SET DPB
parameters
About the RNC- To query the RNC-oriented LST FRC
oriented FRC FRC algorithm parameters
algorithm parameters
To set the RNC-oriented FRC SET FRC
algorithm parameters
About the To query the connection- LST
connection-oriented oriented algorithm switches CORRMALGOSWITCH
algorithm switches
To set the connection-oriented SET
algorithm switches CORRMALGOSWITCH
About the PRACH To modify the PRACH MOD PRACHUUPARAS
parameters over UU parameters over UU interface
interface
II. Parameter Reconfiguration on the NodeB Side
None.
III. Examples
1) Example 1
 Task: Enable the uplink outer-loop power control switch and downlink power
balancing switch.
 Command:
SET CORRMALGOSWITCH:
PCSWITCH=OLPC_SWITCH-1&DOWNLINK_POWER_BALANCE_SWITCH-1;
2) Example 2
 Task: Modify the TFCIPO, TPCPO, and PILOTPO of the downlink DPCCH to 3
dB, 4 dB, and 5 dB respectively.
 Command:
SET FRC: TFCIPO=12, TPCPO=16, PILOTPO=20;
3) Example 3
 Task: Modify the adjust factor of uplink SIR to 5.
 Command:
SET OLPC: SIRADJUSTFACTOR=5;
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77. 1.8.3 Disabling Power Control
The power control is a basic feature. Therefore, it can only be adjusted instead of
being disabled.
1.9 Maintenance Information
1.9.1 Alarms
None.
1.9.2 Counters
None.
1.10 References
 3GPP, 25.211 “Physical channels and mapping of transport channels onto
physical channels (FDD)”
 3GPP, 25.214 "Physical layer procedures (FDD)"
 3GPP, 25.331 "RRC Protocol Specification"
 3GPP, 25.433 “UTRAN Iub interface NodeB Application Part (NBAP) signaling”
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