iBTS Downlink Power Management NORTEL NETWORKS CONFIDENTIAL UTRAN Core WNE1

iBTS iBTS Dowlink Dowlink Power ManagementPower ManagementUTRAN Core WNE

11/Dec/2003

iBTS Downlink Power Management NORTEL NETWORKS CONFIDENTIAL UTRAN Core WNE2

Introduction

Parameter from OMCBlue

Parameter computed and used internally in the iBTSGreen

MeaningColor

iBTS Downlink Power Management NORTEL NETWORKS CONFIDENTIAL UTRAN Core WNE3

Glossary of used terms

OMC Parameters

– TmaAccessType : This parameter can have three values (noTma, tmaUmtsOnly, tmaMix)– AntennaConnectionList : This parameter gives the radio configuration of the iBTS– MaximumPowerAmplification: Used to select working mode of PA (30W or 45W)

Internal iBTS Parameters– TXOUTx_cables_loss : Represents the sum of total cable losses from PA to reference

antenna connector; calculated by CCM (described Slides 5,6)– DDM_xy_loss : Represents the losses introduced by DDM on DL radio path; it’s a

measured value stored in DDM’s EEPROM– TxSpl_x_loss : Represents the losses introduced by TxSplitter on DL radio path; it’s a

measured value stored in Splitter’s EEPROM. Only for OTSR,OTBR– PA_x_modei_PPR_pwr : Represents the nominal maximum output power (dB)of PA with

PA in Mode 1 or Mode 2– PA_MODE: The default vaule is 1 (45W). It is equal to 2 (30W) if either mode 1 is not

possible (e.g. thermal reasons) or MaximumPowerAmplification restricts its value to mode 2.

– MaxDLPowerCapability : Its value is calculated through the procedure described in slide 5

iBTS Downlink Power Management NORTEL NETWORKS CONFIDENTIAL UTRAN Core WNE4

Power Settings Rules

Street iBTS and MCPA Mode:If there are more than 2 MCPA in the street iBTS, then PA_Mode is forced at (2 = 30W) for thermal reason. Therefore, the maximumPowerAmplificationmust be 30W.

iBTS Maximum Downlink Power capabilityThe iBTS calculates, as described on the next slide, its real power transmission capability (internal parameter MaxDlPowerCapability).This corresponds to the maximum allowed power at the reference point, taking into account the maximum power amplification, insertion losses and cables losses between the PA output and the reference point.

At cell setup, the iBTS compares the calculated value MaxDlPowerCapability with the requested valueMaxTxPower, to check if the configuration is compliant with the iBTS capability (See slide 13)

Multi Frequency Power Sharing:Considering multi frequencies configuration, the iBTS uses the same PA for one sector to amplify the signal of the carriers.For each carrier, the parameter PaRatio is used to manage the PA power sharing between frequencies. It represents the percentage of the total PA power Associated to each cell.

MaxDlPowerCapability (Fx) = MaxDlPowerCapability (Mono freq) + 10 * log10(PaRatio/100)Note: obviously, the summation of all PaRatio values referring to the same PA must not reach over 100 % !

iBTS Downlink Power Management NORTEL NETWORKS CONFIDENTIAL UTRAN Core WNE5

MaxDlPowerCapability Calculation

CCM/iCCM

21

Calculate

TRM/iTRM

Calculate

5

Values reported on TRM’s demand to TRM

TxSplitter DDMPA

Note: The value of lossesFor DDM and Splitter areMeasured ones and storedIn EEPROM on the module

)1031(10log.10____

3

1

10__

∑=

++x

lossxyDDMlossxTXspllosscablesTXOUTX

)2/3(10log10)1021(10log.10____

2

1

10__

+++ ∑=x

lossxyDDMlossxTXspllosscablesTXOUTX

lossxyDDMlosscablesTXOUTX ____ +

PA_x_modei_PPR_pwr -

TRM reports calculated MaxDLPowerCapability =

(OTSR)

(OTBR)

(STSR)

6

7Reports calculated TXOUTx_cables_loss(see next slides)and PA_MODE receivedfrom PA

3

OMC Inputs- TmaAccessType- AntennaConnectionList

PA_x_mode1_PPR_pwrPA_x_mode2_PPR_pwr TxSpl_x_loss DDM_xy_loss

4

Reports : MaxDLPowerCapability

Note: this is considered at theReference Point

iBTS Downlink Power Management NORTEL NETWORKS CONFIDENTIAL UTRAN Core WNE6

Assumed Values of losses

0.3 dBTMA_Tx_Way_loss

0.5 dBTxSpl_x_loss

0.5 dBDDM_xy_loss

Nominal Insertion Losses

Losses relative to Cables inside the iBTS are coded into SW and cannot be changed by operator (see next slides)

Losses relative to DDM, TxSplitter are measured at manufacturing and stored in equipment’s EPROM : they’re read by iBTS SW and used to calculate MaxDLcapability of iBTS.

Note :Values in the table are then only Nominal (TYPICAL)

Note : Losses of splitter are given considering that ingoing power is split in three equal parts but also that, as from an emission point of view only one cell is available, all power emitted by each of the 3 branches is re-emitted in the same cell (no loss coming from the split of the power, only attenuation introduced by propagation through the device). This is the used value for power calculations. To obtain the available power at ONE output of TxSplitter 5dB additional losses (10Log(1/3) ) have to be counted.

iBTS Downlink Power Management NORTEL NETWORKS CONFIDENTIAL UTRAN Core WNE7

Feeders Attenuation

Configuration dependant

Configuration dependant

Recommended Value

0Float[0..20] dBStep = 0.1

AntennaAccessAttenuationFeederDiv

0Float[0..20] dBStep = 0.1

AntennaAccessAttenuationFeederMain

Default ValueRange & UnitObjectParameter

Losses due to feeder must be datafilled through the parameters AttenutationFeederMain andAttenuationFeederDiv, corresponding to losses as defined in the following slides.

iBTS Downlink Power Management NORTEL NETWORKS CONFIDENTIAL UTRAN Core WNE8

Configuration without TMA: Reference point (1/2)

TRM

PA DDM

iBTS

Reference Point

Internal cabling Losses = 0.8 dB

Antenna Feeder

Losses = AttenuationFeederXXX

Total Losses from PA output to reference point = Internal cabling + DDM Insertion losses + AttenuationFeederXXX

The reference point is the point so that losses between the iBTS feeder connector (output of the cabinet) and this point are equal to the datafilled value of AttenuationFeederXXX.In this slide, the reference point is considered at the antenna connector, thus supposing the value of AttenuationFeederXXX is correctly set.

iBTS Downlink Power Management NORTEL NETWORKS CONFIDENTIAL UTRAN Core WNE9

Configuration without TMA: Reference point (2/2)Case AttenuationFeederXXX = 0

TRM

PA DDM

iBTS

Internal cabling Losses = 0.8 dB

Reference Point

Antenna Feeder

Total Losses from PA output to reference point = Internal cabling + DDM Insertion losses

In Case AttenuationFeederXXX = 0, the reference point is the iBTS Antenna connector

iBTS Downlink Power Management NORTEL NETWORKS CONFIDENTIAL UTRAN Core WNE10

Configuration with TMA: Reference point (1/2)

TRM

PA DDM

iBTS

Internal cabling Losses = 0.8 dB

Antenna FeederTMA

Losses = AttenuationFeederXXX

Reference PointJumper

Total Losses from PA output to reference point =

Internal cabling + DDM Insertion losses + AttenuationFeederXXX + TMA Insertion Losses + Jumper losses

When a TMA is specified, the transmission power reference point moves to the output of the TMA

iBTS Downlink Power Management NORTEL NETWORKS CONFIDENTIAL UTRAN Core WNE11

Configuration with TMA: Reference point (2/2)

The TMA insertion losses are equal to 0.3 dB in the transmission path.Jumper losses are set to 2*0.6 dB (0.6 dB for each jumper).The calculation of losses between the cabinet output and the reference point are then calculated according to the following rule:

IFattenuationFeederXXX = 0

THENa constant value of 2dB for feeder losses is taken into account for calculations.TXOUTx_cables_losses = 3.2 dB =2 dB + 2*0.6 dB

ElseThe datafilled value is used.TXOUTx_cables_losses = AttenuationFeederXXX + 0.6dB + 0.6dB

iBTS Downlink Power Management NORTEL NETWORKS CONFIDENTIAL UTRAN Core WNE12

OTSR ConfigurationAdditional cabling Losses = 0.3 dB

TRM

PA DDM

iBTS Tx SplitterInsertion losses = 0.5 dB

Internal cabling Losses = 0.8 dB

For OTSR and OTBR configurations, additional losses must be considered:• one additional internal cable between TxSplitter and DDM. Losses = 0.3 dB• TxSplitter insertion losses = 0.5 dB (typical value)

iBTS Downlink Power Management NORTEL NETWORKS CONFIDENTIAL UTRAN Core WNE13

MaxTxPower Setting

RuleRule::The following rule must be verified:

MaxTxPower > maxDlPowerCapability -15 dB

Operator dependant

Recommended ValueSTSR W/o TMA:

45 (1 carrier)42 (2 carriers)

Float[0..50] dBmStep = 0.1

FddCellMaxTxPower

Default ValueRange & UnitObjectParameter

The maximum allowed transmission power for all downlink physical channels added together (common + traffic) within a cell is requested through the setting of the maxTxPower parameter of the FDDCell object. This parameter can be tuned independently for each cell and must take into account the power partitioning between cells served by the same PA.

Cell SetupThe RNC sends the datafilled value MaxTxPower in NBAP Cell Setup Message, and the iBTS checks the compatibility of this value with the real transmission capability (MaxDlPowerCapability), based on hardware and configuration constraints.

If MaxTxPower < MaxDlPowerCapability, the cell setup is OKIf MaxTxPower > MaxDlPowerCapability, the cell setup fails.

iBTS Downlink Power Management NORTEL NETWORKS CONFIDENTIAL UTRAN Core WNE14

Common Channels Settings

In the overhead, the Pilot power, i.e. the P-CPICH power is defined by the pcpichPower parameter of the FDDCell object as an absolute value in dBm, at the reference point.

-3 dBM.2PCHpichPowerRelativeToPcpichPICH

-7 dBC.2RACHaichPowerRelativeToPcpichAICH

-3 dBM.2SCCPCHsccpchPowerRelativeToPcpichS-CCPCH

-2 dBC.2FDDCellbchPowerRelativeToPcpichP-CCPCH

-5 dBC.2FDDCellsschPowerRelativeToPcpichS-SCH

-5 dBC.2FDDCellpschPowerRelativeToPcpichP-SCH

10% of maxTxPower(~ MaxTxPower -10 dB)

C.2FDDCellpcpichPowerPCPICH

Recommended ValueClassObjectparameterChannel

RuleRule::PcpichPower > MaxTxPower – 15 dB

Justification: Check in in iBTS CCM at cell Setup

iBTS Downlink Power Management NORTEL NETWORKS CONFIDENTIAL UTRAN Core WNE15

Dedicated Channels Settings

Maximum and Minimum power (MaxDlTxPower and MinDlTxPower parameters) for each dedicated channel (Dl User Service) is datafilled in DlUsPowerConf Object.

Configured per DluserServiceFloat[-35..15] dBRelative to pcpich Power

DlUsPowerConfMinDlTxPower

Configured per DluserServiceFloat[-35..15] dBRelative to pcpich Power

DlUsPowerConfMaxDlTxPower

Range & UnitObjectParameter

Rule:Rule:minDlTxPower + pcpichPower ≥ MaxTxPower- 28dB

iBTS Downlink Power Management NORTEL NETWORKS CONFIDENTIAL UTRAN Core WNE16

SummaryP-

Cpi

ch

PcpichPowerP-

SCH

P-C

CPC

H

S-SC

H

S-C

CPC

H

AIC

H

PIC

H

PschPowerRelativ

SschPowerRelativeTo

BchPowerRelati

SccpchPowerRel

AichPowerRelativ

PichPowerRelativ

Common Channel Dedicated Channel

MinDlTxPower

MaxDlTxPower

PO1forTfciBitsPO2forTpcBitsPO3forPilotBits

Max

imum

28

dB

15 d

B

Allo

wed

Ran

ge fo

r PcpichPower

MaxTxPower ich

ich

Pcpic

ToPcpi

cpich

ich

chh

eToPcp

eToPcp

Pcp

veTo

eToP

ative

DPD

CH

DPC

CH

Time multiplexed

iBTS Downlink Power Management NORTEL NETWORKS CONFIDENTIAL UTRAN Core WNE17

Impact of feeder attenuationUL Open Loop Power Control

Pini(PRACH) = pcpichPower + UL_interference + constantValue - P-CPICH_RSCP

TMA

PA

With MHA, the uplink gain in the iBTS is adjusted (in the DDM) in order that the overall chain is similar to the one of an iBTS without MHA.

Hence, the open loop parameters are kept identical for configuration with and without MHA.

No need to modify constantValue Parameter

DDM

TRM