umt irc dd 020708 v01 02 en r99&hsxpa link budget guidelines

R'99 & HSxPA Link Budget Guidelines

Document number: UMT/IRC/DD/020708 Document issue: V01.02 / EN Document status: Standard Date: 24/04/2007

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UMT/IRC/DD/020708 V01.02 / EN Standard 24/04/2007 /73

PUBLICATION HISTORY

Current Document

R’99 & HSxPA Link Budget Guidelines [UMT/IRC/DD/020708]

for R’99 & HSxPA Link Budget Tool [UMT/IRC/APP/020707]

April 24, 2007

1.2, En, Draft

Document update for the release of R’99 & HSxPA Link Budget Tool v1.1

Sylvestre DEMONGET

• Modifications on 4.5.1: own signal contribution removed in UL Interference Margin computation

• Update of R’99 and HSUPA Eb/N0 values

• Modifications on 4.2.7: Rx (Tx) feeder loss computed according to exact UL (DL) carrier frequency

• Modifications on 3.2.2.DCH Margin, 3.2.2.Power Available for HSDPA

• Corrections

December 12, 2006

1.1, En, Standard

Modifications after team review

Sylvestre DEMONGET

• Completion of Publication History

• Modifications on 3.3.3 (HSDPA Throughput calculation), 4.4.3 (Shadowing Margin), 4.6.1 (HSDPA UE Category)

• Addition of UE Antenna Gain in all link budget related formulas

• Corrections




October 27, 2006

1.0, En, Draft

Creation

Sylvestre DEMONGET

• Merge of the 2 prior link budget guidelines UMTS Link Budget Guidelines (for WCDMA Link Budget Baselines tool) and HSDPA Link Budget Guidelines (for HSDPA Link Budget tool).

• On the basis of this merge, creation of new guidelines (i.e. current document R’99 & HSxPA Link Budget Guidelines) covering all the aspects of W-CDMA Network Engineering latest UMTS link budget tool R’99 & HSxPA Link Budget Tool (v1.0)

• Addition of contents which covers functionalities specific to R’99 & HSxPA Link Budget Tool: DL Sector Capacity calculation, Forward Link Required Power calculation, HSUPA




Guidelines for prior ex-Nortel UMTS Link Budget too ls

HSDPA Link Budget Guidelines [UMT/IRC/INF/014579]

for HSDPA Link Budget tool

July 16, 2006

1.8, En, Draft

Corrections

Raphael TRINH

July 26, 2005

1.7, En, Draft

Corrections

Carine CAPGRAS

• Update of Eb/N0 values

June 24, 2005

1.6, En, Draft

Corrections

Carine CAPGRAS

April 06, 2005

1.5, En, Draft

Corrections

Carine CAPGRAS

March 03, 2005

1.4, En, Draft

Corrections

Carine CAPGRAS

February 15, 2005

1.3, En, Draft

Changes

Carine CAPGRAS

• UE Rx Diversity

• HSDPA Multi-User Gain (MUG)




January 13, 2005

1.2, En, Draft

Main changes

Carine CAPGRAS

October 05, 2004

1.1, En, Draft

Creation

Carine CAPGRAS

UMTS Link Budget Guidelines [UMT/IRC/INF/15]

for UMTS Link Budget Baselines tool

November 04, 2004

4.2, En, Standard

Modification

Carine CAPGRAS

• Introduction of Train environments


• Update of BTS Noise Figure

November 13, 2002

1.15, En, Standard

Modification

David VINAGRE


February 29, 2002

1.14, En, Standard

Modification

David VINAGRE

• Modification on DL Processing Gain calculation

• Modification on Antenna Tilt calculation


• Document update for the release of WCDMA Link Budget Baselines v4.2




October 10, 2001

1.13, En, Standard

Modification

David VINAGRE


June 18, 2001

1.12, En, Standard

Modification

David VINAGRE

• Modifications on SHO Gain on capacity

March 01, 2001

1.11, En, Standard

Modification

David VINAGRE

• Addition of user’s guide for WCDMA Link Budget Baselines tool

February 26, 2001

1.10, En, Standard

Modification

David VINAGRE

• Modifications on Soft Handover (SHO) Gain

September 29, 2000

1.8, En, Standard

Modification

Marthe LAUNE


September 08, 2000

1.7, En, Standard

Modification

Marthe LAUNE





July 28, 2000

1.6, En, Standard

Modification

Marthe LAUNE


June 21, 2000

1.5, En, Standard

Modification

Marthe LAUNE

• Addition of Node-B Eb/N0 values

March 10, 2000

1.4, En

Modification, Standard

Marthe LAUNE

• Addition of Downlink Link Budget

December 24, 1999

1.3, En


Marthe LAUNE

November 28, 1999

1.2, En


Marthe LAUNE

June 28, 1999

1.1, En

Creation, Standard

Marthe LAUNE




CONTENTS

1. INTRODUCTION..........................................................................................................................10

1.1. OBJECT..................................................................................................................................10

1.2. SCOPE OF THIS DOCUMENT .....................................................................................................11

1.3. AUDIENCE FOR THIS DOCUMENT ..............................................................................................11

2. RELATED DOCUMENTS .................................. ..........................................................................12

2.1. APPLICABLE DOCUMENTS ........................................................................................................12

2.2. REFERENCE DOCUMENTS........................................................................................................12

3. LINK BUDGET CALCULATION PRINCIPLE .................. ...........................................................14

3.1. UPLINK LINK BUDGET..............................................................................................................14

3.1.1 Available Reverse Link Budget calculation ...................................................................15 3.1.2 Maximum Coverage Range calculation ........................................................................17 3.1.3 Uplink Sector Capacity calculation................................................................................18

3.2. DOWNLINK LINK BUDGET.........................................................................................................19

3.2.1 Downlink Maximum Total Path Loss calculation...........................................................20 3.2.2 Power Amplification dimensioning ................................................................................21 3.2.3 Downlink Sector Capacity calculation ...........................................................................24 3.2.4 Forward Link Required Power calculation ....................................................................26

3.3. HSDPA .................................................................................................................................27

3.3.1 impact on Uplink Link Budget........................................................................................27 3.3.2 impact on Downlink Link Budget ...................................................................................29 3.3.3 Throughput calculation..................................................................................................30

3.4. HSUPA .................................................................................................................................37

3.4.1 impact on Uplink Link Budget........................................................................................38 3.4.2 impact on Downlink Link Budget ...................................................................................39 3.4.3 Throughput calculation..................................................................................................40

4. INPUT PARAMETERS FOR “R’99 & HSXPA LINK BUDGET TOOL ” .....................................42

4.1. ENVIRONMENT........................................................................................................................43

4.1.1 Propagation Environment..............................................................................................43 4.1.2 UMTS Frequency Band.................................................................................................44 4.1.3 BTS Antenna Height .....................................................................................................44 4.1.4 Environment Correction Factor .....................................................................................45 4.1.5 Correlation Coefficient...................................................................................................45 4.1.6 Total Standard Deviation...............................................................................................46 4.1.7 Penetration Loss ...........................................................................................................47 4.1.8 Orthogonality Factor......................................................................................................47

4.2. BASE TRANSCEIVER STATION (BTS)........................................................................................48

4.2.1 Eb/N0 Values..................................................................................................................48 4.2.2 Common Control Channels Tx Power ..........................................................................53 4.2.3 Sectorization..................................................................................................................54 4.2.4 UL Frequency Reuse Efficiency....................................................................................54 4.2.5 DL Ie/Ii Target.................................................................................................................55 4.2.6 CPICH Ec/I0 Target........................................................................................................55 4.2.7 Feeders .........................................................................................................................56 4.2.8 BTS Noise Figure..........................................................................................................57




4.2.9 BTS Antenna Gain ........................................................................................................57 4.2.10 BTS Maximum Tx Power per sector (PA) .....................................................................57 4.2.11 Diversity.........................................................................................................................57 4.2.12 TMA...............................................................................................................................58

4.3. USER EQUIPMENT (UE) ..........................................................................................................59

4.3.1 Eb/N0 Values..................................................................................................................59 4.3.2 UE Maximum Tx Power ................................................................................................59 4.3.3 UE Noise Figure ............................................................................................................59 4.3.4 Activity Factor................................................................................................................60 4.3.5 Body Loss......................................................................................................................60

4.4. QUALITY OF SERVICE (QOS) ...................................................................................................61

4.4.1 BLER Target..................................................................................................................61 4.4.2 Area Reliability ..............................................................................................................61 4.4.3 Shadowing Margin ........................................................................................................62

4.5. R’99 SPECIFIC SETTINGS........................................................................................................63

4.5.1 Max. Allowed UL Noise for R’99 Traffic ........................................................................63 4.5.2 DL Power Ratio Reserved for R’99 Traffic....................................................................65 4.5.3 UL Noise Rise Reserved for R’99 Traffic ......................................................................65

4.6. HSDPA SPECIFIC SETTINGS...................................................................................................66

4.6.1 HSDPA UE Category ....................................................................................................66 4.6.2 Power Control for HS-SCCH.........................................................................................70

4.7. HSUPA SPECIFIC SETTINGS...................................................................................................71

4.7.1 Max. Allowed Noise Rise for R’99+HSUPA Traffics .....................................................71

5. ABBREVIATIONS AND DEFINITIONS...................... .................................................................72

5.1. ABBREVIATIONS ......................................................................................................................72

5.2. DEFINITIONS ...........................................................................................................................73




1. INTRODUCTION

1.1. OBJECT

When answering a UMTS RFI or RFQ, a cell count is often required to evaluate the cost of the UMTS deployment. The first step consists in evaluating the typical cell/site coverage and capacity for a given bearer service and a given type of environment. This is the purpose of the link budget.

In UMTS, coverage and capacity are linked and are both key quantities to evaluate the quality of a network design. Therefore, the link budget for UMTS must compute both maximum cell range (coverage) and uplink/downlink capacities. Basically, the link budget computes those outputs independently for each service.

Concerning HSDPA, there is a need to know the impact of HS-DPCCH (HSDPA-specific uplink feedback channel) on the uplink link budget, and the impact of HS-SCCH (HSDPA-dedicated downlink control channel) and DCH Margin (downlink power margin applied to HSDPA downlink power) on the downlink link budget. In addition, it is useful to know the HSDPA single user throughput according to distance from site.

On the other hand, concerning HSUPA there is a need to know the impact of E-HICH (HSUPA-specific downlink feedback channel for HARQ) and E-AGCH/E-RGCH (HSUPA-specific downlink grant channels) on the downlink link budget. Again, it is useful to know the E-DCH single user throughput according to distance from site.

The tool presented in this document – W-CDMA Network Engineering (ex-Nortel Core Wireless Network Engineering) R’99 & HSxPA Link Budget Tool [A1] – covers all the aspects mentioned above.

The present document describes the functionalities and use rules for this tool, and more generally explains the UMTS link budget methodology of ex-Nortel.

Ex-Nortel UMTS link budget calculation principles are detailed in Chapter 3.

The input parameters for the tool and their default values are listed in Chapter 4.




1.2. SCOPE OF THIS DOCUMENT

Two guides for ex-Nortel UMTS link budget already exist:

• UMTS Link Budget Guidelines [R7], which is the first document about UMTS link budget and covers Release 99 aspects. It is associated with the tool UMTS Link Budget Baselines [R8].

• HSDPA Link Budget Guidelines [R9], which was written later and covers both Release 99 and HSDPA aspects, with a strong focus on the second point. It is associated with the tool HSDPA Link Budget [R10].

The current document covers Release 99, HSDPA and H SUPA aspects all together; it is associated with R’99 & HSxPA Link Budget Tool [A1].

Since this tool includes almost all the functionalities of the previously developed two tools, some contents from above two documents was reused and eventually modified/updated here.

Following are some of the totally new contents:

• 3.2.3 Downlink Sector Capacity calculation

• 3.2.4 Forward Link Required Power calculation

• 3.4 HSUPA

• 4.3.1 Eb/N0 Values

All Chapter 3, except 3.3 HSDPA, has been newly written (basically contents do not differ much though, especially parts concerning the uplink link budget methodology and HSDPA). All the contents about HSUPA, the explanations about how interaction between R’99, HSDPA and HSUPA is handled in the tool have been newly added.

1.3. AUDIENCE FOR THIS DOCUMENT

• W-CDMA Network Engineering, PLM, Regional Engineering teams, Presales teams, Marketing teams.

• Anyone who uses R’99 & HSxPA Link Budget Tool [A1] or needs information on ex-Nortel UMTS link budget calculation principles.




2. RELATED DOCUMENTS

2.1. APPLICABLE DOCUMENTS

[A1] UMT/IRC/APP/020707 R99&HSxPA Link Budget Tool

2.2. REFERENCE DOCUMENTS

[R1] PE/IRC/APP/99 “Nortel GSM link budget tool V5 user guide”, Samuel Youn – 26/11/1998

[R2] 3GPP, TR 25.890 v1.3.0 “High Speed Downlink Packet Access: UE Radio Transmission and Reception (FDD)”, Release 5

[R3] ETSI, TR 101 112 v3.2.0 “Selection procedures for the choice of radio transmission technologies of the UMTS”, UMTS 30.03 version 3.2.0

[R4] 3GPP, TS 25.101 v5 “User Equipment (UE) radio transmission and reception (FDD)”, Release 5

[R5] 3GPP, TS25.214 “Physical layer procedures (FDD)”, Release 5

[R6] 3GPP, TS25.213 “Spreading and modulation (FDD)”, Release 5

[R7] UMT/IRC/INF/15 “UMTS Link Budget Guidelines”, M. Laune, David Vinagre, Carine Capgras, 04/11/2004

[R8] “WCDMA_LB_Baselines_v4.8.xls”, 11/2004

[R9] UMT/IRC/INF/014579 “HSDPA Link Budget Guidelines”, Carine Capgras, Raphael Trinh, 11/2004

[R10] “HSDPA_Link_budget_V2.0.xls”, Carine Capgras, Raphael Trinh, 08/2006

[R11] UMT/BTS/ “Power Setting for Downlink Common Channels”, 19/08/2002

[R12] UMT/BTS/INF/019652 “HSUPA Handbook v3.1”, Michael Morette, 16/11/2006

[R13] “RFS Products Edition 4”, The Clear Choice, 03/2006

[R14] “Edge, Area reliability, SHO Gain and Link Margin of CDMA Systems”, Muhieddin Najib, 08/2002

[R15] UMT/IRC/APP/014654 “HSDPA Engineering Guide v1.11”, 10/10/2006




[R16] UMT/SYS/APP/019929 “Utran Dim Tool User Guide”, Boris Widmann, Ludovic Angot, Yann Lacheteau, Rani Makké, 22/12/2006

[R17] UMT/BTS/DD/017476 “HSDPA Service Enhancement – Node-B Functional Specification”, Bastien Massie, 22/09/2006




3. LINK BUDGET CALCULATION PRINCIPLE

This chapter aims at giving a general view of ex-Nortel UMTS link budget. It presents the calculation principles for the uplink link budget, the downlink link budget, HSDPA throughput and HSUPA throughput. It also covers the impact of HSDPA and HSUPA on the uplink and the downlink link budget.

Concepts such as cell count, maximum allowable path loss, uplink link budget and downlink link budget have already been presented in Nortel GSM link budget tool V5 user guide [R1]. Hence, this chapter focuses more on UMTS-specific aspects of the link budget.

3.1. UPLINK LINK BUDGET

The methodology applied for UMTS uplink link budget is summarized in Figure 3-1.

For each uplink service (i.e. RAB such as CS64), the link budget tool first computes the Uplink Maximum Allowable isotropic Path Loss (UL MA PL), which is the maximum air interface path loss allowable when taking into account the mobile maximum output power, Alcatel-Lucent Node-B performances (i.e. Eb/N0 Target), and environment. After this, Available Reverse Link Budget is derived by subtracting engineering margins (see Chapter 4) from UL MAPL. Then the Maximum Coverage Range (i.e. cell range) for the considered uplink service is directly derived from Available Reverse Link Budget thanks to Hata propagation model, which gives the relationship between distance and air interface path loss.

Besides, Uplink Sector Capacity , i.e. the number of active users that can be supported per sector is also computed for each uplink service, assuming a certain Uplink Cell Load parameter.

For the specific case of HSUPA, above quantities are derived for several E-DCH “services”, i.e. for several E-DCH throughput values.

Figure 3-1: Uplink link budget principle

Body Loss

BTS Antenna Gain

•Slant Loss

•Cables and Connectors Loss

Penetration Loss

Node-B sensitivity (for uplink service i) Available

Reverse Link Budget

Shadowing Margin (compensation of shadowing and fast fading)

Uplink Interference Margin (Compensation of interf. from other UEs)

UE Max. Tx Power




3.1.1 AVAILABLE REVERSE LINK BUDGET CALCULATION

For a given uplink service i, the Uplink Maximum Allowable isotropic Path Loss (UL MAPL) [dB] is given by the following formula (logarithmic scale):

With

• UE Max. Tx Power [dBm]: mobile maximum output power.

• NodeB Sensitivity(i) [dBm]: Alcatel-Lucent Node-B sensitivity for uplink service i and for considered environment. The reference point is at the BTS bulkhead (in the uplink direction, before the Dual Duplexer Module (DDM)).

o NodeB Thermal Noise [dBm]: thermal noise power received by the Node-B (Node-B Noise Figure taken into account).

o PG(i): Processing Gain for service i:

Chip Rate being UMTS chip rate (3.84Mcps) and r(i) the user data rate for service i, e.g. 64kbps for CS64.

• UE Ant. Gain [dBi]: gain of the mobile antenna compared to an isotropic antenna, i.e. an ideal antenna that radiates power with unit gain uniformly in all directions. Although the mobile antenna is almost omnidirectional regarding the 3d space, UE Ant. Gain is introduced in the link budget in order to take into account the loss in the mobile antenna performances at frequencies different from the optimal work frequency.

• BTS Ant. Gain [dBi]: gain of the BTS antenna in the direction of interest, compared to an isotropic antenna.

• Rx Cables&Connectors Loss [dB]: in the BTS reception chain, sum of the losses due to the feeder and jumpers. Rx Cables&Connectors Loss does include the influence of Tower-Mounted Amplifier (TMA) if used. For more information on the handling of TMA in the link budget tool, please see 4.2.12.

• Slant Loss [dB]: polarization loss for a cross-polar antenna, if such antenna is used.

)()()(0

iPGiNENoiseThermalNodeBiySensitivitNodeB

Target

b −+=

)()( irRateChipiPG =

LossSlant LossConnectorsRx Cables&

GainAntBTSGainAntUE

iySensitivitNodeBPowerTxMaxUEiMAPLUL

−−++

−=..

)(.)(




The Available Reverse Link Budget is then derived by subtracting engineering margins to UL MAPL (logarithmic scale):

With

• Shadowing Margin [dB]: margin used to compensate time/space-dependent (but not directly dependent to distance from site) losses in the air interface path loss, i.e. shadowing, fast fading and variations in penetration loss. Shadowing Margin is set so that uplink service i can be statistically offered to the user AR% of the time (AR: Area Reliability). For more information on Shadowing Margin computation on values, please see 4.4.3.

• Uplink Interference Margin [dB]: margin used to compensate the interference generated by other users on the uplink. It depends directly on Max. allowed UL Noise Rise for R'99 traffic (Max. allowed UL Noise Rise for R'99+HSUPA traffics if HSUPA is enabled) which is the parameter in the link budget tool that sets the maximum amount of traffic on the uplink.

• Penetration Loss [dB]: used to take into account the loss in signal power as the signal travels from indoor to outdoor and vice versa. It translates losses due to reflection and absorption.

• Body Loss [dB]: loss in the signal strength due to the absorption by the human body of the user.

MarginUplinkTotalMAPL(i)ULBudget(i)LinkReverseAvailable −=

LossBodyLossnPenetratio

MarginceInterferenUplinkMarginShadowingMarginUplinkTotal

+++=




3.1.2 MAXIMUM COVERAGE RANGE CALCULATION

The Maximum Coverage Range or cell range is directly derived from the Available Reverse Path Loss for a specific Dimensioning Uplink Service, i.e. the uplink service chosen to be the one to derive Maximum Coverage Range from (usually CS64 is used).

The reason for deriving the cell range basing on uplink considerations and not downlink is that, due to the limited output power of the mobile compared to the BTS maximum output power, considering the single user case the uplink has a tighter available path loss than the downlink in the majority of the cases. However, it may happen for the downlink to be the limiting direction for coverage, for example when using a TMA or a BTS with very low output power such as indoor equipment. The link budget tool gives as an output the limiting direction for coverage.

Below propagation models are used in the link budget to give the relationship between Maximum Coverage Range (distance) and Available Reverse Path Loss (air interface path loss):

• 1700, 1900 and 2100MHz bands : COST 231 Hata Model

• 850MHz band : Hata Model for Urban Areas

With

• L [dB]: air interface path loss

• f [MHz]: UMTS carrier frequency

• h [m]: BTS antenna height

• d [km]: distance between BTS and UE

• C: Environment Correction Factor (takes a specific value according to the environment type, i.e. Dense Urban/Urban/Suburban/Rural)

Typical values for above parameters can be found in Chapter 4.

CdhhfL +⋅−+−+= log)log55.69.44(log82.13log9.333.46

CdhhfL +⋅−+−+= log)log55.69.44(log82.13log16.2655.69




3.1.3 UPLINK SECTOR CAPACITY CALCULATION

For each uplink service, the link budget computes the Uplink Sector Capacity (i.e. maximum number of active users supported per sector), basing on Max. allowed UL Noise Rise for R’99 traffic (Max. allowed UL Noise Rise for R'99+HSUPA traffics for uplink capacity concerning HSUPA traffic). This last parameter used in the link budget corresponds to a parameter used in Alcatel-Lucent UTRAN (rtwpMaxCellLoadNonEdch) to avoid uplink overload. Please see 4.5.1 and 4.7.1 for more information on this.

In the link budget tool, Max. allowed UL Noise Rise is first converted into a maximum uplink cell load value, basing on the following formula which gives the relationship between these two quantities (linear scale):

The uplink cell load gives the amount of uplink traffic, as a percentage of Pole Capacity which is the maximum theoretical number of users (all using the same service i) supported per sector when assuming Cell Range tending towards 0 meter.

Bellow is the “N-Pole Formula” which gives Pole Capacity for uplink service i (linear scale):

With

• FR: Frequency Reuse Efficiency.

With Ii being Uplink Intra-cell Interference, i.e. power received at Node-B coming from all users in own sector, and Ie being Extra-cell Interference, i.e. power received at Node-B coming from other users.

• AF(i): Activity Factor for service i.

The activity factor used in the link budget does not reflect the ON-time ratio within a session as would do the activity factor in the true sense. The link budget tool aims to provide results independently for each service; hence basically it is not designed to work under a specific call profile assumption. In the link budget, AF(i) is usually taken 0.5 for Speech (in order to take into account discontinuous transmission feature of speech codec) and 1 for all other services.

ULie

i

II

IFR

+=

⋅

⋅+=

SHOTarget

b

Pole

GiNEiAF

FRiPGiN

)()(

)(1)(

0

LoadCellULRiseNoise

−=

1

1




• GSHO: soft/softer handover gain on Eb/N0 Target. Typically taken 1dB (constant).

Finally, for each uplink service, Uplink Sector Capacity is obtained by multiplying Pole Capacity by the uplink cell load:

3.2. DOWNLINK LINK BUDGET

The principle of UMTS downlink link budget is summarized in Figure 3-2.

The first step of the downlink link budget is the computation of Downlink Maximum Total Path Loss , which is the downlink path loss from the BTS Power Amplifier (it does include Tx Cables&Connectors Loss) to a mobile located at the cell edge, i.e. Maximum Coverage Range derived previously in the uplink link budget. The reason for computing a quantity that includes BTS cable and connector losses (although quantities derived for the uplink do not) is that the downlink total path loss from the BTS power amplifier to the mobile is useful to derive quantities such as Downlink Sector Capacity or HSDPA Sector Throughput, as explained later.

After this, BTS power amplification dimensioning is performed. This step consists in computing the necessary transmit power for each common control channel and the DCH Margin which is a power margin that applies only to HSDPA downlink power. This allows knowing the Power available for HSDPA (per BTS PA), by subtracting above quantities and Power reserved for R’99 Traffic (i.e. assumption concerning R’99 downlink power) from the BTS maximum output power per sector and per carrier (referred as PA in the link budget).

The Downlink Sector Capacity is derived for each R’99 downlink service. The downlink capacity is derived assuming all the BTS output power (except power reserved for the common control channels) available for R’99 traffic. Similarly for the uplink, Uplink Sector Capacity was derived basing on the maximum allowed uplink load. Besides, the purpose of Power reserved for R’99 Traffic parameter is only the calculation of Power available for HSDPA which is used for HSDPA Sector Throughput computation.

In addition, the Forward Link Required Power , which is the transmit power required for BTS PA to send a specific downlink service i to a mobile located at the cell edge, is computed for each downlink service.

Figure 3-2: Downlink link budget principle

LoadCellULiNiCapacitySectorUL Pole ⋅= )()(

Body Loss

•Cables and Connectors Loss

•Slant Loss

Penetration Loss

For

war

d Li

nk

Req

uire

d P

ower

(U

E a

t cel

l edg

e, D

L S

ervi

ce i

)

DL Max. Total PL (from BTS PA to UE)

Available Reverse LB + Frequency Shift

Shadowing Margin (compensation of shadowing and fast fading)

BTS Ant. Gain




3.2.1 DOWNLINK MAXIMUM TOTAL PATH LOSS CALCULATION

The Downlink Maximum Total Path Loss , which is the downlink path loss from the BTS PA to the mobile, can be directly derived from Available Reverse Link Budget as follows (logarithmic scale):

With

• Frequency Shift [dB]: additional loss (or gain) on the downlink air interface path loss compared to the uplink due to the use of FDD. Basically it is a loss since carrier frequency is higher for the downlink.

Considering the propagation models used, Frequency Shift is given by:

o For 1700, 1900 and 2100MHz bands:

o For 850MHz band:

• Coupling Loss [dB]: loss due to the Dual Duplexer Module (DDM) which is the last radio element after the power amplifier inside the BTS. Coupling Loss is not included in the uplink link budget, since the reference point for BTS sensitivity is the input (uplink direction) of the DDM.

• Tx Cables&Connectors Loss [dB]: in the BTS transmission chain, sum of the losses due to the feeder and jumpers. Takes into account the influence of TMA, if used. Note that DDM Coupling Loss is not included in Tx Cables&Connectors Loss.

LossBodyLossnPenetratioMarginShadowing

LossSlantLossCables&ConTxLossCoupling

GainAnt.BTSGainAnt.UE

ShiftFrequencyBudgetLinkReverseAvailablePLTotalMax.DL

++++++

−−+=

.

( )..log9.33 FreqCarrierULFreqCarrierDLShiftFrequency =

( )..log16.26 FreqCarrierULFreqCarrierDLShiftFrequency =




3.2.2 POWER AMPLIFICATION DIMENSIONING

The power amplification dimensioning part of the link budget consists in the calculation of the required transmit power for each downlink common control channel (CCCH) and the HSDPA-specific DCH Margin.

This allows knowing the Power available for HSDPA. For the specific case of the downlink link budget part of the tool, PA dimensioning also allows knowing Power reserved for R'99 Traffic. Power reserved for R'99 Traffic is an input parameter; however, in the downlink link budget, where all the BTS available power is allocated to R’99 traffic, it is calculated by the tool by subtracting CCCH Tx Power from the BTS maximum output power PA.

CPICH TX POWER

The first step in the link budget PA dimensioning process is the computation of the transmit power for the downlink common pilot channel (CPICH). Indeed, all other common control channels have a transmit power that is specified as CPICH Tx Power plus an offset in dB, in other words CCCH Tx Power can be directly derived from CPICH Tx Power.

W-CDMA Network Engineering recommends CPICH Ec/I0 Target = -15dB (for more details about the motivation of this value, please refer to [R11]). This means that the received Ec/I0 for the CPICH must be statistically higher than -15dB AR% of the time (AR: Area Reliability), for a user moving randomly inside its serving sector. Thus, CPICH Tx Power must be chosen so that the above condition on coverage quality is verified, which can be written as follows (linear scale):

With

• Ec/I0 at the mobile is defined as:

d being the distance between the mobile and the site.

• DL Ii (cell edge): Downlink Intra-cell Interference at cell edge, i.e. total power received by a UE at cell edge coming from the BTS PA of its own sector.

• DL Ie (cell edge): Downlink Extra-cell Interference at cell edge, i.e. total power received by a UE at cell edge coming from the BTS PAs of other cells/sectors.

The values for DL Ii (cell edge) and DL Ie (cell edge) in the link budget depends on the Area Reliability parameter. These values are directly derived from DL Ie/Ii Target variable, which value is detailed in 4.2.5.

( )NoiseThermalUEedgecellIDLedgecellIDL

PLTotalMax.DLIECPICHPowerTxCPICH

ei

Target0

c

++×

×=

)()(

NoiseThermaldIDLdIDL

dEdI

E

ie

c

0

c

++=

)()(

)()(




COMMON CONTROL CHANNELS TX POWER

The downlink common control channels taken into account in the link budget are basically CPICH, P-CCPCH, S-CCPCH, PICH and AICH.

Additionally,

• When HSDPA is enabled: HS-SCCH is taken into account for the calculation of Power available for HSDPA, which is used for HSDPA throughput computation. HS-SCCH is not taken into account in the downlink link budget part of the tool, because the downlink link budget works under the assumption that all BTS power is for R’99 traffic and HSDPA traffic is null.

• When HSUPA is enabled: E-AGCH and E-HICH are taken into account in the downlink link budget, because we consider users actually using E-DCH on the uplink. HS-SCCH is taken into account only for the calculation of Power available for HSDPA.

The transmit power for each of the above channels can be deduced from CPICH transmit power by adding a known offset in dB.

Total transmit power for common control channels is then derived as follows.

• HSDPA and HSUPA disabled:

• HSDPA enabled:

• HSUPA enabled:

For each of the above mentioned channels, the value of the power offset relative to CPICH transmit power is given in 4.2.2. Concerning the downlink link budget part of the tool, HS-SCCH Tx Power is excluded from above formulas because of the assumption that HSDPA traffic is null.

PowerTxAICHPowerTxPICHPowerTxCCPCHS

PowerTxCCPCHPPowerTxCPICHPowerTxCCCH

++++=

PowerTxSCCHHS



++++

+=

PowerTxHICHEPowerTxAGCHE

PowerTxSCCHHS



+++

++++=




DCH MARGIN

The DCH Margin is a power margin at Node-B level that applies only to HSDPA power. Hence, it does not impact the downlink link budget where the focus is kept on R’99 traffic. The role of this margin is to ensure that there is no overload due to downlink DCH traffic (i.e. R’99 traffic) sudden fluctuation. Indeed, DL DCH traffic fluctuation may be important and fast changing because of the DCH power control trying to combat the interference due to HSDPA traffic.

The DCH Margin parameter is specified as proportional to (Non HSDPA Tx Power - CPICH Tx Power).

POWER AVAILABLE FOR HSDPA

By definition, Power available for HSDPA is the BTS power remaining after subtracting common control channels transmit power, Power reserved for R’99 Traffic and the DCH Margin.

Power available for HSDPA is given as follows (linear scale):

{ }0,99Max MarginDCHTrafficRforreservedPowerPowerTxCCCPA

HSDPAforavailablePower

−−−=




3.2.3 DOWNLINK SECTOR CAPACITY CALCULATION

DOWNLINK SECTOR CAPACITY

For each downlink service, Downlink Sector Capacity can be derived from the BTS maximum output power per sector PA, the power for common control channels CCCH Tx Power, Maximum Coverage Range and assumptions on UE performances. The downlink cell load is not an input parameter like the uplink cell load (strictly speaking Max. allowed UL Noise Rise) was for the uplink. It is a result derived from Downlink Sector Capacity, as can be seen below.

For each R’99 downlink service i, Downlink Sector Capacity (i.e. the maximum number of active users that can be supported per sector) is the ratio of the power available for R’99 traffic to the downlink transmit power Preq required to send i to a UE experiencing mean path loss. Since in the downlink link budget part of the tool HSDPA traffic is assumed null, Downlink Sector Capacity can be written as follows (linear scale):

(3a)

Since in UMTS Ec/N0 is defined as the received signal to interference and noise ratio, Ec/N0 and Preq are linked together as follows, for a UE experiencing Downlink Mean Total Path Loss (linear scale):

(3b)

With

• Downlink Mean Total Path Loss: downlink total path loss from BTS PA to the mobile, averaged over entire cell area. It is directly derived from Downlink Maximum Total Path Loss by dividing it by a constant (which can be obtained by integrating the linear value of a path loss over a round area). Below formula for Downlink Mean Total Path Loss is given in linear scale:

with Propagation Coefficient being the exponent for attenuation due to distance in the propagation model, i.e. the distance attenuation loss is 10*Propagation Coefficient dB per decade of distance.

Referring to 3.1.2, Propagation Coefficient is equal to:

( ) reqPPowerTxCCCHPACapacitySectorDL −=

PLTotalMeanDLNoiseThUEPOFPAOFI

IMeanDL

PLTotalMeanDLiP(i)N

E

reqi

e

req

Target0

c

⋅+⋅−⋅+=

.)(

),(

tCoefficiennPropagatio2

2PLTotalMaxDLPLTotalMeanDL

+=

10

)log(55.69.44 HeightAntennaBTStCoefficiennPropagatio

⋅−=




• DL Mean Ie/Ii: downlink extra-cell interference at DL Mean Total PL over downlink intra-cell interference at DL Mean Total PL. Simulations showed that this value does not depend much on the cell range neither than the Area Reliability parameter. Hence, it is taken equal to a fixed value (60%) in the link budget.

• OF: Orthogonality factor between UMTS downlink OVSF codes. OF depends on the environment, e.g. gets worse when delay spread becomes large. OF value ranges from 0 to 1, OF=0 meaning perfect orthogonality. OF values according to environment types are specified in 4.1.8.

Downlink Sector Capacity for downlink service i is derived by introducing Preq deduced from Equation (b) into Equation (a):

Finally, the formula used in the link budget tool is obtained by converting Ec/N0 into Eb/N0, taking into account Activity Factor for service i and the soft/softer handover gain on capacity (as in 3.2.3). Below the formula is given in linear scale:

ASYMPTOTIC CAPACITY

Basically, Asymptotic Capacity is for the downlink what Pole Capacity is for the uplink.

Basing on above Downlink Sector Capacity formula, PA can be written as a function of the other quantities. Asymptotic Capacity is then the Downlink Sector Capacity value that makes denominator null in the formula giving PA. Following is the Asymptotic Capacity formula (linear scale):

( )

PLTotalMeanDLNoiseThUEPAOFI

IMeanDL

PowerTxCCCHPA(i)NEOF

iCapacitySectorDL

i

e

Target0

c

⋅+⋅+

−⋅

+

=

−

.)()(

1

( )


IMeanDL

PowerTxCCCHPAGiPG

(i)NE

OF

iAFiCapacitySectorDL

i

e

SHO

Target0

b

⋅+⋅+

−⋅

⋅+

⋅=

−

.)(

)(

)(

1)(

1

OFI

IMeanDL

GiPG

(i)NE

OF

iAFiN

i

e

SHO

Target0

b

Asymp

+

⋅+

⋅=

−1

)(

)(

1)(




DOWNLINK CELL LOAD

By definition, Downlink Cell Load is the ratio of DL Sector Capacity to Asymptotic Capacity (linear scale):

In addition, the direct formula can be obtained by changing DL Sector Capacity and Asymptotic Capacity by their respective expressions in above formula:

3.2.4 FORWARD LINK REQUIRED POWER CALCULATION

One more output of the downlink link budget is Forward Link Required Power , i.e. the BTS transmit power required to send service i to one UE located at cell edge. The calculation of the Forward Link Required Power for a certain service i allows knowing whether cell range is limited by the uplink or by the downlink. Indeed, if Forward Link Required Power is higher than the BTS maximum output power (per sector, per carrier) PA, this is the sign that the downlink is the limiting direction for coverage.

From 3.2.3 we know the required BTS transmit power to send i to a mobile experiencing mean path loss:

Forward Link Required Power is then obtained by changing above formula for the cell edge case instead of the mean path loss case:

DL Ie/Ii at cell edge being the ratio of DL Ie (cell edge) to DL Ii (cell edge) as mentioned in 3.2.2.CPICH Tx Power.

)()()( iNiCapacitySectorDLiLoadCellDL Asymp=

OFI

IMeanDL

PLTotalMeanDLNoiseThUEPA

PowerTxCCCHPAiLoadCellDL

i

e +

⋅+

−=.

)(

1

)(

.)(

),( −

⋅+

⋅+⋅+=

SHO

Target0

b

i

e

req

GiPG

(i)NE

OF


IMeanDL

PLTotalMeanDLiP

1

)(

..)(

−

⋅+

⋅+⋅+

=

SHO

Target0

b

edgecelli

e

GiPG

(i)NE

OF

PLTotalMaxDLNoiseThUEPAOFI

IDL

PowerReq.LinkForward




+

+=

22

1*c

hs

c

dDPCCHPerMaxUETxPow

ββ

ββ

3.3. HSDPA

The introduction of HSDPA in a “shared carrier” scenario (i.e. R’99 and HSDPA are both supported on the same UMTS carrier) impacts both uplink and downlink link budgets since new channels are introduced concerning both directions. Figure 3-3 shows HSDPA-specific channels.

Figure 3-3: HSDPA-specific channels

Concerning, the impact of the HSDPA-specific DCH Margin on Node-B transmit power, it has been discussed above in 3.2.2.DCH Margin.

On the other hand, the link budget tool also computes HSDPA single user throughput according to distance from site. The computation principle will is presented in 3.3.3.

3.3.1 IMPACT ON UPLINK LINK BUDGET

The presence of HS-DPCCH feedback channel (uplink) increases the energy per user data bit necessary to send a certain amount of data on the uplink. In other words, for each uplink R’99 service i, the Eb/N0 Target(i) required to assure a certain BLER after decoding will get higher when HS-DPCCH is introduced.

As showed in Figure 3-4 (extract from [R6]), uplink DPCCH, DPDCHs and HS-DPCCH are spread to the chip rate thanks to channelization codes cc, cd,j and chs respectively. Each of the spread signals is then weighted by a gain; βc for DPCCH, βd for DPDCHs and βhs for HS-DPCCH.

For the single HS-DPDCH case, which is the case for which the impact of HS-DPCCH on the uplink link budget is the most important, the loss in Eb/N0 Target(i) due to HS-DPCCH introduction is the same for any service i and can be derived as follows.

The maximum mobile output power can be written:




Figure 3-4: Spectrum spreading for uplink DPCCH, DP DCHs and HS-DPCCH

Thus, the DCH available power is:

Finally, the loss in Eb/N0 Target [dB] is given by:

The values in the link budget for βc, βd and βhs, and the resulting loss in uplink Eb/N0 Target are specified in 4.2.1.HSDPA .

+++

⋅=

++−⋅=

−= −

222

22

222

2

1

hsdc

dc

hsdc

hs

DPCCHHSDCH

erMaxUETxPow

erMaxUETxPow

PerMaxUETxPowP

βββββ

ββββ

+++

=222

22

0log10

hsdc

dc

Target

b LossNEUL

βββββ

DPDCHn I Σ

j

cd,1 βd

Sdpch,n

I+jQ

DPDCH1

Q

cd,3 βd

cd,2 βd

DPDCH2

cc βc

DPCCH Σ

S

chs

HS-DPCCH (If Nmax-dpdch mod 2 = 1)

chs

HS-DPCCH (If Nmax-dpdch mod 2 = 0)

βhs

βhs

cd,6 βd

DPDCHn+1




3.3.2 IMPACT ON DOWNLINK LINK BUDGET

As shown in Figure 3-3, HSDPA needs a specific control channel HS-SCCH on the downlink to tell the mobile about channelization codes in use for HS-PDSCH channels, modulation scheme, Transport Block Size, etc. In the link budget, basically we consider the case when only one HSDPA user is scheduled at one time, so HS-SCCH Tx Power in 3.2.2.Common Control Channels Tx Power refers to the output power for one HS-SCCH.

In the tool, HS-SCCH is taken into account for the calculation of Power available for HSDPA, but is not in the downlink link budget part, as explained in 3.2.2.Common Control Channels Tx Power. HS-SCCH Tx Power value in the link budget may be changed by the routine that derives HSDPA Sector Throughput if the option “Power Control for HS-SCCH” has been activated.

Please see 4.2.2 for more information on HS-SCCH Tx Power handling in the link budget tool.

Concerning the DCH Margin, its impact on the power available for HSDPA has been discussed in 3.2.2.DCH Margin.




3.3.3 THROUGHPUT CALCULATION

PRINCIPLE

In the HSDPA Throughput part of the link budget, the following quantities are computed:

• HSDPA Single User Throughput according to distance from site

• HSDPA Sector Throughput derived basing on HSDPA Single User Sector Throughput. HSDPA Single User Sector Throughput is taken equal to HSDPA Single User Throughput at Downlink Mean Total Path Loss (approximation).

• Maximum Coverage Range according to HSDPA Single User Sector Throughput Target. HSDPA Single User Sector Throughput Target is an input parameter.

The HSDPA throughput depends on rapid adaptation of the transmission parameters to the instantaneous radio conditions. Thanks to the CQI (Channel Quality Indicator), information about channel condition is sent to the Node-B. The throughput is then adapted according this CQI feedback.

In addition, rapid retransmission of erroneous packets from the Node-B without involving the RNC is made possible by using HARQ (Hybrid Automatic Repeat Request).

The CQI tables in this document show the transport block size, the number of codes and the modulation (QPSK or 16-QAM) according to the CQI.

The relationship between HS-DSCH Ec/N0 received at the mobile (i.e. signal to interference and noise ratio for the considered HSDPA transport channel) and the CQI then sent by the mobile can be approximated as follows:

(3c) 0N

EDSCHHSBACQI c×+=




Figure 3-5: Relationship between HS-DSCH E c/N0 (referred as “C/I”) and CQI for 6, 10 and 12 UE category

The value of coefficient A used in the link budget tool is made varying according to the mobile speed (which depends on the environment selected):

Speed A

3 km/h 15.5

50 km/h 14.3

120 km/h 13.3

CQI according to C/I(dB)

5

10

15

20

25

30

-10 -5 0 5 10 15

C/I (dB)

CQ

I

CQI - category 6

CQI - category 10

CQI - category 12




HS-DSCH Ec/N0 experienced at the mobile according to the distance from site d is derived as follows:

With

• Ie /Ii (d): downlink extra-cell interference at distance d from site over downlink intra-cell interference also at distance d from site. The value for Ie /Ii (d) is known from system simulations. A table of values for Ie /Ii (d) has been implemented in the link budget tool.

• n HS-PDSCH: number of HS-PDSCH physical channels (i.e. number of codes) for the HS-DSCH transport channel used by the considered user

Following is the formula giving HS-DSCH Ec/N0 when using reception diversity at the mobile:

Once HS-DSCH Ec/N0 has been calculated for several values of d, the CQI reported by the mobile can be deduced using equation (3c). Finally, HSDPA Single User Throughput (according to distance d) is derived from the CQI value using CQI tables. For more information on the CQI tables used in the tool, please refer to Chapter 4.

( )

( )

( ) )(.)(

)(.)()(

.)(

)(

.

)(

0

dPLTotalDLNoiseThUEPAdI

IPowerTxPDSCHHSPAOF

PowerTxPDSCHHS

dPLTotalDLNoiseThUEdIdI

IPowerTxPDSCHHSPAOF

PowerTxPDSCHHS

NoiseThUEIdLossPathTotalDLPowerTxPDSCHHSPAOF

dLossPathTotalDLPowerTxDSCHHS

NoiseThUEIP

dLossPathTotalDLPowerTxPDSCHHSN

EPDSCHHS

i

e

ii

e

e

ei

c

⋅+⋅+−⋅=

⋅

+⋅+−⋅

=

++−⋅=

++=

GainDivRxUE


I

PDSCHHSn

PowerTxDSCHHSPAOF

PowerTxDSCHHSN

EDSCHHS

i

e

c

.

)(.)(0 ⋅+⋅

+

−⋅

=

00 NEPDSCHHSPDSCHHSnN

EDSCHHS cc ×=

)(.)(0


I

PDSCHHSn

PowerTxDSCHHSPAOF

PowerTxDSCHHSN

EDSCHHS

i

e

c

⋅+⋅+

−⋅

=




MULTI-USER GAIN

Thanks to the HSDPA-specific Node-B fast scheduler, the average HSDPA sector throughput increases when the number of simultaneous active HSDPA users increases. The total gain on HSDPA sector throughput brought by the scheduler is referred as MUG (Multi-User Gain).

In Alcatel-Lucent UTRAN release UA5.0, basically the maximum HS-DSCH transmit power that one user can be allocated is equal to the CPICH transmit power multiplied by the Measurement Power Offset Γ. More precisely, the transmit power for the HS-DSCH of considered user u is calculated by the Node-B as follows (logarithmic scale):

(3d)

With:

• Γ : Measurement Power Offset. Fixed value (6dB).

• ∆CQI (u): Power Adjustment. Value computed by the Node-B according to the CQI reported by the mobile. Basically, the aim of the Power Adjustment parameter is to reduce HS-DSCH transmit power when the user is in good reception condition. In UA5.0 release, it is also used to boost HS-DSCH transmit power for reported CQI values lower than 5 (see 4.6.1 for more details on this last point).

As shown in Equation (3d), HS-DSCH transmit power per user is limited in UA5.0 release. Consequently, besides the scheduler gain, referred below as MUG PF, there is also an obvious increase on HSDPA sector throughput when several users are scheduled in the same TTI because the total transmit power used for HSDPA increases then. This second contribution is referred as MUG TTI below.

Below, these two contributions for HSDPA multi-user gain are presented in more details.

MUG PF

The value for the scheduler gain MUG PF according to the number of active HSDPA users depends on the scheduler type, environment, average speed of the mobiles, employment of receive diversity at the mobiles, etc. In UA5.0 release, the following scheduler types are available for HSDPA:

• Round Robin

• Maximum C/I

• Nortel Proportional Fair

• Classical Proportional Fair

• Pure Proportional Fair

By default, the scheduler used in UA5.0 release is Nortel Proportional Fair.

For a detailed explanation on each scheduler type, please refer to [R17].

Figure 3-6 shows the principle of Maximum C/I scheduling.

)()( u∆ΓPowerTxCPICHuPowerTxDSCHHS CQI++=




0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2-35

-30

-25

-20

-15

-10

-5

0

5

Tim e (s ec )

Fas

t F

adin

g am

plitu

de (

dB)

P roport ional F a ir S c heduling princ ip le

U s er 1U s er 2

User 2 scheduled User 1 scheduled

Maximum C/I scheduling

Figure 3-6: Proportional Fair scheduling

With Maximum C/I scheduling (and Proportional Fair scheduling with a lower gain though), transmitting to users with favorable short term radio conditions (TTI = 2 ms) can increase significantly the throughput compared to Round Robin scheduling.

The cell throughput increases with the number of active users whereas the user throughput decreases. Indeed, chances to find several users with good radio conditions increases when a lot of active users are present; on the other hand, if many active users are present, the inactive time periods (when other users are served) are longer, hence the user throughput is reduced.

Figure 3-7 shows the shape of the scheduler gain on HSDPA Cell Throughput according to the number of active users per cell, for Nortel Proportional Fair scheduling.

Figure 3-7: Multi-User-Gain according to the number of users for Pedestrian A @ 3km/h

0 5 1 0 1 5 2 0 2 5 3 00

1 0

2 0

3 0

4 0

5 0

6 0

7 0

8 0M u lt i-U s e r G a in - P e d e s t ria n _ a - 3 k m /h

# u s e rs p e r c e ll

MU

G %

1 R X2 R X




In the HSDPA Throughput calculation part of the link budget tool, the following assumptions are made for the computation of MUG PF:

• Nortel Proportional Fair scheduling algorithm

• 20 active users

In addition, when using receive diversity at the mobile, MUG PF is slightly reduced in order to take into account the fact that the mobile experiences less fast fading.

MUG TTI

The gain on HSDPA cell throughput obtained by the increase in the total power allocated to HS-DSCH transport channels due to the simultaneous scheduling of 2 or more users within the same TTI, MUG TTI, depends on Measurement Power Offset Γ, HSDPA UE Category and Power available for HSDPA (see 3.2.2.Power Available for HSDPA for more information on this parameter of the link budget).

The maximum allowable power per HSDPA user, MAPHU, is defined according to Γ and the CPICH transmit power. MUG TTI is by definition null if Power available for HSDPA is lower than MAPHU. If MAPHU is lower than 50% of Power available for HSDPA, then two users ore more can be scheduled.

The characteristic of MUG TTI according to Power available for HSDPA is shown in Figure 3-8 (blue curve).

Figure 3-8: Multi-user Gain on Power for ΓΓΓΓ = 6 dB

0 10 20 30 40 50 60 70 800

20

40

60

80

100

120

HSDPA power (%)

MU

G (

%)

MUG vs. HSDPA power

Total MUGMUG_TTI




Finally, after computing the above two contributions, the total HSDPA multi-user gain MUG is derived as follows:

With n being the number of HSDPA active users per sector.

Total multi-user gain MUG is shown by the red curve in Figure 3-8.

THROUGHPUT

The value of HSDPA Single User Throughput according to distance d is derived from the Transport Block Size given by the pair {CQI( d ), UE Category}.

Since the wanted throughput is at RLC level, the number of RLC PDU that can be sent within one Transport Block is first calculated:

Then the throughput is derived by taking into account the number of user data bits per data unit at RLC level (i.e. RLC SDU size) as follows:

The RLC throughput per HS-PDSCH is:

Finally, taking into account the BLER 1st transmission:

−=sizePDUdMAC

sizeheaderhsMACSizeBlockTransportTBperSDURLCn floor

( )TTIsizeSDURLCTBperSDURLCnThroughputRLC ⋅=

( ) ( ).1 trans1stBLERTTISizeSDURLCTBperSDURLCnThroughputRLC −⋅⋅≈

),,()(

),(

nΓHSDPAforavailablePowerTTIMUGnPFMUG

nHSDPAforavailablePowerMUG

+=




3.4. HSUPA

As for HSDPA, the introduction of HSUPA on a shared carrier with R’99 impacts both uplink and downlink link budgets. The channels in use for an HSUPA user are shown in Figure 3-9.

Concerning the uplink, in the link budget tool the case when a mobile uses E-DCH for data transfer and generates traffic on an uplink R’99 channel at the same time (e.g. uploading data while making a speech or video call) is not considered.

However, the impact of the HSUPA feature of the network on a mobile using R’99 on the uplink is taken into account in the link budget tool. The Uplink Interference Margin (mentioned above in 3.1.2) even for a pure R’99 user is computed according to the maximum noise rise that can occur in an HSUPA enabled network.

For the downlink, the impact of HSUPA-specific downlink channels E-HICH and E-AGCH is taken into account.

Besides, the tool computes the E-DCH single user throughput according to distance from site, on the base of R&D performance results for E-DCH

Figure 3-9: HSUPA-specific channels

HSUPA UE

Node-BE-DPDCH

DCH (DPCCH/DPDCH)

E-DPCCHE-AGCH

E-HICH/E-RGCH

HSUPA UE

Node-BE-DPDCH

DCH (DPCCH/DPDCH)

E-DPCCHE-AGCH

E-HICH/E-RGCH




3.4.1 IMPACT ON UPLINK LINK BUDGET

Concerning the impact of the HSUPA feature on a mobile using R’99 on the uplink, it is handled in the link budget tool throughout the Uplink Interference Margin. Basically, in the HSUPA enabled case, for both R’99 and HSUPA users, Uplink Interference Margin is derived directly from Maximum Allowed UL Noise Rise for R'99+HSUPA Traffics parameter, which is referred as totalRotMax in Alcatel-Lucent RAN Model. See Chapter 4 for more details on Noise Rise input parameter and Uplink Interference Margin calculation in the tool.

On the other hand, when in HSUPA enabled mode the tool computes a standard link budget with uplink Eb/N0 Target values for E-DCH. More precisely speaking, an uplink link budget set of results is computed for several values of E-DCH single user throughput. For each E-DCH throughput value i considered, the corresponding Eb/N0 Target(i) necessary to achieve this throughput is applied to the formulas of the uplink link budget. For more information on E-DCH throughput values available in the tool and the corresponding Eb/N0 Target values, please refer to 4.2.1.HSUPA .

E-DCH Eb/N0 values applied in the link budget tool are based on the link level simulation results presented in Chapter 5 “Nominal E-DPDCH” of HSUPA Handbook [R12].

In the simulations of Chapter 5 of [R12], DPCCH SIR (i.e. Eb/N0) received at Node-B is fixed thanks to power control; on the other hand the power offset for E-DPDCH(s) βed is made change within one simulation. The results for E-DCH throughput are associated with the E-DPDCH Ec/N0 received at Node-B, but βed is not explicitly provided.

Therefore, some conversion has been applied to the values of [R12] in order to obtain E-DCH Eb/N0 values applicable to the link budget, i.e. where Eb includes not only E-DPDCH power but also E-DPCCH, DPDCH, DPCCH and HS-DPCCH powers.

Following are the conversion formulas (linear scale):

0

2

22222

0 NEDPDCHsE

n

nN

E c

eded

hscdeceded

Total

c ⋅⋅

++++⋅=

ββββββ




Then ned βed is deduced from E-DPDCH(s) Ec/N0 (i.e. abscissa on the throughput graphs in [R12]) as follows (linear scale):

Where DPCCH Ec/N0 is (linear scale):

After converting E-DPDCH(s) Ec/N0 values given in [R12] into E-DCH Eb/N0 values, the next step is to chose, for each E-DCH throughput value, one E-DCH Transport Format Combination (E-TFC) and its corresponding E-DCH Eb/N0. Indeed, a specific E-DCH throughput can be achieved using different E-TFCs; the difference resides in the Eb/N0 and the average number of HARQ transmissions necessary to achieve this throughput. In order to obtain the E-DCH Eb/N0 values applicable in the link budget tool, for each E-DCH throughput value the E-TFC requiring the lowest Eb/N0 has been kept.

3.4.2 IMPACT ON DOWNLINK LINK BUDGET

HSUPA-specific downlink channels, i.e. E-HICH (feedback for HARQ) and E-AGCH/E-RGCH (grant channels) consume some of the BTS output power originally available for downlink traffic. In Alcatel-Lucent UA5.0 release, the relative grant channel for E-RGCH is not supported.

Concerning E-AGCH and E-HICH, in the link budget tool the total power used for these channels (DL HSUPA Tx Power) is assumed constant and is computed as follows:

With

• E-AGCH Tx Power: transmit power for one E-AGCH channel.

• αE-AGCH: coefficient between 0 and 1 chosen according to the supposed amount of HSUPA traffic. It is assumed that only one absolute grant is sent at one time.

• E-HICH Tx Power: transmit power per signature for one E-HICH channel. Up to 40 acknowledgements (1 bit) can be sent simultaneously on the same E-HICH using orthogonal signatures. E-HICH transmit power is proportional to the number of signatures used.

• nE-HICH: average number of signatures used for the E-HICH.

The values in the link budget tool for above parameters are specified in 4.2.2.

PowerTxHICHEnPowerTxAGCHEPowerTxHSUPADL HICHEAGCHE ⋅+⋅= α

0

0

2

2

NEDPCCH

NEDPDCHsE

nc

cc

eded

⋅=⋅

ββ

2560

0

Target

b

cSIRDPCCH

PGDPCCH

NEDPCCH

NEDPCCH ==




3.4.3 THROUGHPUT CALCULATION

The E-DCH single user throughput at MAC-e level according to distance from site is computed in the link budget tool as summarized in Figure 3-10.

With HSUPA, the shared resource in the uplink is noise rise (for HSDPA it is BTS output power). Therefore, in order to derive the E-DCH throughput one must know how much uplink noise rise is generated by R’99 traffic. In the link budget tool, it is possible to input this through the UL Noise Rise reserved for R'99 Traffic parameter. Besides, the maximum uplink noise rise allowed by the network for the total of R’99 and HSUPA traffics is set through a parameter in the RNC: totalRotMax. Thus, it is possible to know the noise rise available for HSUPA, referred as Max. allowed UL Noise Rise for R’99+HSUPA Traffics in the tool.

E-DCH throughput is computed for several distances, ranging from a distance close to the site, e.g. 50m to the cell edge. For each distance, the uplink total path loss, i.e. path loss from the mobile to the BTS Dual Duplexer Module (DDM) plus the engineering margins is derived as follows:

• First, the uplink air interface path loss according to distance is derived using Hata propagation model, presented in 3.1.2.

• The uplink total path loss is derived from the air interface path loss as follows:

Figure 3-10: E-DCH single user throughput calculati on principle

Max. allowed UL Noise Rise for R’99+HSUPA traffics

Distance from Site

UL Total Path Loss

(from UE to BTS DDM)

Highest reachable E-DCH throughput

UL Noise Rise reserved for R'99 traffic

Max. allowed UL Noise Rise for HSUPA traffic

MarginUplinkTotal

LossSlant LossConnectorsRx Cables&GainAnt.RxBTS

LossPathAirULLoss(d)PathTotalUL

+−−+

=




Finally, the E-DCH single user throughput is computed basing on above-mentioned Max. Allowed UL Noise Rise for HSUPA Traffic, the uplink total path loss and the knowledge of E-DCH Eb/N0 Target(i) values, i being a particular E-DCH throughput value as explained in 3.4.1.

It has been verified that Eb/N0 Target(i) obtained from R&D simulations gets higher as throughput i increases. Therefore, for each distance d considered, the E-DCH throughput computation routine of the link budget tool checks if throughput i can be reached, following i ascending order. The check consists in testing the two following points:

• Is the mobile transmit power required to achieve Eb/N0 Target inferior or equal to the mobile maximum output power?

• Is the noise rise generated by user inferior to Max. allowed UL Noise Rise for HSUPA Traffic?

If the two above conditions are tested true, then the next throughput value is tested. At the end of the loop, i found is the highest E-DCH throughput reachable by user, in other words the single user E-DCH throughput.




4. INPUT PARAMETERS FOR “R’99 & HSXPA LINK BUDGET TOOL”

This chapter presents the main input parameters for R’99 & HSxPA Link Budget Tool [A1]. In the tool, all input parameters can be specified by the user in the first sheet named Parameters.

For each item, the type of the item (i.e. input or variable ), the values as implemented in the tool, the parameter purpose and eventually its impact on the link budget calculation are presented.

Concerning the Parameter sheet, here are a few recommendations that may help the user when using the tool:

• At the opening of the tool, all the parameters are automatically set to their default value.

• After modifying one ore more parameters, it is possible to bring back default values by clicking the Reset button at the top of the screen (see Figure 4-1).

• Input items are values in red, list boxes and check boxes. Each of them may be modified as will by the user.

• Values in blue are variables , i.e. values computed by the program basing on some input parameters. Ad well as user inputs, variables are used for the computation of the link budget. Basically they should not be changed, but it is possible to do so if the user thinks that it is necessary.

• A red small triangle beside a parameter shows that a comment exists. Looking at the comment may be useful to quickly have an idea of the purpose of some parameter.

• Once the parameters have been properly set, the computation of the link budget is launched by clicking the Compute button at the top of the screen (see Figure 4-1). The program then jumps automatically to the results sheet, i.e. the second sheet named LB.

Figure 4-1: Compute and Reset buttons




4.1. ENVIRONMENT

Figure 4-2: Environment

4.1.1 PROPAGATION ENVIRONMENT

Type: Input

Default value: “Dense Urban, ITU Pedestrian A 3km/h”.

Possible values:

• “Dense Urban, ITU Pedestrian A (B) 3km/h”: pedestrian applications in city centers.

• “Urban, ITU Pedestrian A (B) 3km/h”: pedestrian applications in cities.

• “Suburban, ITU Pedestrian A (B) 50km/h”: pedestrian applications in residential or low urban areas.

• “Rural, ITU Vehicular A (B) 120km/h”: typical in car/train applications in rural areas (motorways, roads and railways).

In the link budget tool, the selection of Propagation Environment determines several variables which are:

• Channel profile (A or B)

• Mobile speed

• Environment correction factor C in the propagation model

• Correlation coefficient ρ

• BTS Antenna Height

• Total standard deviation σTot for variations in path loss

• Orthogonality factor OF between UMTS downlink OVSF codes

• Eb/N0 table in use

For each service i, link level simulations results give Eb/N0 Target(i) values for Alcatel-Lucent BTS according to the specified error ratio target, i.e. BLER or BER.

Because Eb/N0 Target(i) depends on the channel profile, the mobile speed etc, several Eb/N0 tables are implemented in the link budget tool. The table used for a specific link budget computation depends on the Propagation Environment selected by the user.




As described in [R2] and [R3], a channel profile is defined by the number of paths and the average amplitude and delay for each path. Real life measurements have shown the occurrence of channel profiles A and B:

Test environment Profile A Profile B Indoor 50% 45%

Outdoor to indoor 40% 55% Vehicular 40% 55%

Table 4-1: Repartition of profiles A and B accordin g to environment

4.1.2 UMTS FREQUENCY BAND

Type: Input

Default value: “2100MHz Band I”

Possible values:

• “2100MHz Band I”

• “1900MHz Band II”

• “1700MHz Band III”

• “850MHz Band V”

Through this parameter, the user can select one of the standard UMTS frequency bands. This item defines Rx Frequency Band and Tx Frequency Band variables, i.e. the low edge of the uplink and the downlink 5MHz band, respectively (FDD is assumed).

4.1.3 BTS ANTENNA HEIGHT

Type: Variable

Default value: 30m

Values:

Propagation Environment BTS Antenna Height [m]

Dense Urban, Urban, Suburban 30

Rural 40

Table 4-2: BTS Antenna Height according to environment

BTS Antenna Height is the elevation of the BTS antenna from the ground level. Actually the value depends on the operator and the country. Most of the time, it is specified in the RFI. If it is the case, the variable value may be overwritten to the specified value.

BTS Antenna Height is used in the propagation model (See 3.1.2).




4.1.4 ENVIRONMENT CORRECTION FACTOR

Type: Variable

Default value: 0

Values:


The Environment Correction Factor (C in propagation model formulas in 3.1.2) is used to tune the propagation models (COST 231 Hata Model and Hata Model for Urban Areas) used in the tool according to selected Propagation Environment. Since these models were originally designed for a dense urban environment, the correction factor for “Dense Urban” is null.

4.1.5 CORRELATION COEFFICIENT

Type: Variable

Default value: 0.5

Values:


Correlation coefficient ρ is a variable that tells about how much are correlated two versions of a same signal that arrive at the BTS from different paths. In rural environment, where fading is generally less important, correlation is high. In dense urban environment, where fading takes an important role, correlation is lower.

Correlation coefficient ρ has an impact on SHO Gain on coverage (see 4.4.3). Indeed, the higher correlation is, the lower will be macro-diversity gain.

Propagation Environment Environment Correction Factor [dB]

Dense Urban 0

Urban -3

Suburban -12

Rural -22

Propagation Environment Environment Correction Fact or [dB]

Dense Urban, Urban, Suburban 0.5

Rural 0.707




4.1.6 TOTAL STANDARD DEVIATION

Type: Variable

Default value: 13.3dB

Values:

Table 4-5: Total standard deviation σTot according to environment

Total standard deviation σTot is the standard deviation for non-deterministic variations in the air interface path loss, i.e. all variations except the distance loss given by the propagation model. For instance, it covers the following variations in the air interface path loss:

• Outdoor shadowing • Indoor shadowing • Penetration Loss • Fast fading

Assuming that above variations are independent one to each other, σTot has been defined as follows:

With

• σOutdoor: STD for outdoor shadowing

• σIndoor: STD for indoor shadowing

• σPene: STD for variation in Penetration Loss

• σPower: STD for variation in transmit power due to power control

Remarks concerning σPower: σPower is the standard deviation for fast variation in the mobile (or the BTS) transmit power, which is due to the use of power control. Therefore, σPower can be viewed as the standard deviation for variations due to both fast fading and change in received interference level. σPower depends on the mobile speed:

• For speeds greater than 50 km/h, fast fading tends to be averaged so σPower becomes lower (σPower typical value: 2dB)

• For low speeds, variations in fast fading become important (σPower typical value: 4dB)

Propagation Environment

σOutdoor

[dB] σIndoor

[dB] σPene

[dB] σPower

[dB] σTot

[dB] Dense Urban,

Urban, Suburban 7 7 8 4 13.3

Rural 10 0 0 2 10.2

2222PowerPeneIndoorOutdoorTot σσσσσ +++=




4.1.7 PENETRATION LOSS

Type: Variable

Default value: 18dB

Values:

Table 4-6: Penetration Loss according to environmen t and frequency

Penetration Loss translates the average loss in the signal power as the signal travels from indoor to outdoor and vice versa.

Most of the time, the figures are specified in the RFI. If this is actually the case, values specified by the customer should be considered carefully because they may include some margin in addition to the average penetration loss. The aim of such margin is to compensate the variation in Penetration Loss. However, since variation in Penetration Loss is handled through σTot (as explained above), the introduction of a margin here would skew the link budget.

4.1.8 ORTHOGONALITY FACTOR

Type: Variable

Default value: 0.15

Values:

Orthogonality Factor OF depends mainly on the multipath channel profile (A or B) and the mobile speed. Above values, which are the defaults in the link budget tool, were computed thanks to W-CDMA Network Engineering System Simulator.

Propagation Environment Penetration Loss [dB]

UMTS Frequency Band: 1700, 1900, 2100MHz

UMTS Frequency Band: 850MHz

Dense Urban 18 15

Urban 15 12

Suburban 10 7

Rural 5 2

Propagation Environment Orthogonality Factor

Dense Urban/Urban Pedestrian A @3km/h 0.15

Dense Urban/Urban Pedestrian B @3km/h 0.57

Suburban Pedestrian A/B @50km/h , Rural Vehicular A/B @120km/h 0.5




4.2. BASE TRANSCEIVER STATION (BTS)

Figure 4-3: Base Transceiver Station

4.2.1 Eb/N0 Values

R'99

Following are the performances (i.e. Eb/N0 Target(i) value that ensure that service i is correctly decoded by the Node-B) of Alcatel-Lucent Node-B with iCEM digital board, for several R’99 services and under several environments. The impact of HSDPA and HSUPA-specific uplink channels is not taken into account here (see below 4.2.1.HSDPA and 4.2.1.HSUPA) .

Simulations have been run on the link level simulator SATURN. Following are the main assumptions that have been made for the simulations:

• BLER=1% (for all services below)

• Rake receiver with 8 fingers

• Rx diversity, assuming a correlation of 0.7 between the two reception paths for Dense-Urban, Urban and Suburban environments (cross-polar antennas, polarization diversity) and 0.5 for Rural environment (vertical polarization antennas, space diversity).

• Turbo coding for data services

• UE Power Control: Algorithm 1

• Voice activity factor gain

• Final Eb/N0 values include an implementation margin of 1dB, which is added in order to take into account software and hardware implementation defects.




The following table indicates which Eb/N0 values are applied in the link budget tool according to the Propagation Environment input parameter:

Figu

ETable 4-7: Origin of the Eb/N0 values applied in the link budget tool

The following table shows the Eb/N0 values applied in the link budget tool. Note that Eb is the energy received per user data bit. Eb does include the energy necessary for signalization, i.e. DPCCH channel.

Table 4-8: Alcatel-Lucent Node-B performances for R ’99 (no HSxPA uplink channels)

Propagation Environment

Environment used in simulation leading to Eb/N0 applied in the link budget tool

Dense Urban, ITU Pedestrian A 3km/h

ITU Pedestrian A Speed 3km/h (PA3)

Dense Urban, ITU Pedestrian B 3km/h ITU Pedestrian A Speed 3km/h (PB3)

Urban, ITU Pedestrian A 3km/h


Urban, ITU Pedestrian B 3km/h

ITU Pedestrian A Speed 3km/h (PB3)

Suburban, ITU Pedestrian A 50km/h


Suburban, ITU Pedestrian B 50km/h

ITU Pedestrian B Speed 50km/h (PB50)

Rural, ITU Vehicular A 120km/h ITU Vehicular A Speed 120km/h (VA120)

Rural, ITU Vehicular B 120km/h

ITU Vehicular B Speed 120km/h (VB120)




HSDPA

As seen in 3.3.1, for a mobile transferring on HSDPA on the downlink, the presence of the CQI feedback channel HS-DPCCH increases the energy per user data bit necessary to send a certain amount of data on the uplink. Indeed, in this case Eb includes not only data and signalization for the uplink R’99 service considered, but also HS-DPCCH power.

The loss in Node-B performances has been derived in 3.3.1:

The following table shows the power offset for the uplink physical channels and the resulting loss in Node-B performances applied in the link budget tool:

Table 4-9: Impact of HS-DPCCH on Node-B performanc es

Remark concerning Speech 12.2 and CS 64:

For the link budget purpose, we assume that basically a user doing a speech or video call does not do data transfer on HSDPA at the same time. Hence, the loss in Node-B performances due to HSDPA is null for these two services.

+++

=222

22

0log10

hsdc

dc

Target

b LossNEUL

βββββ




HSUPA

As explained in 3.4, when set in HSUPA-enabled mode by user the tool computes a standard link budget for E-DCH services, i.e. several values of E-DCH single user throughput. For each E-DCH throughput value i considered, the corresponding Eb/N0 Target(i) necessary to achieve this throughput is applied to the formulas of the uplink link budget.

E-DCH Eb/N0 values applied in the link budget tool are based on the link level simulation results presented in Chapter 5 “Nominal E-DPDCH” of HSUPA Handbook [R12].

Following are some of the assumptions that have been made for the simulations:

• E-DPCCH present

• E-DPDCH not present (hence βd=0)

• Inner Loop Power Control: ON

• Outer Loop Power Control: OFF

• DPCCH SIR Target : 0, -3, -6dB (per antenna. Corresponds to +3, 0, -3dB for 2 antennas)

• βed not fixed (takes several values within one result curve)

• ACK/NACK and E-DPCCH signaling: No errors

• HARQ combining: Incremental Redundancy

• Maximum number of HARQ transmissions: 12

• Channel estimation: Real (not ideal)

• Rake receiver

• Rx diversity

• Turbo coding

• No implementation margin added




The conversion method to obtain the E-DCH Eb/N0 values applicable in the link budget tool from the values of [R12] has been presented in 3.4.1.

The following table shows the E-DCH Eb/N0 values applied in the link budget tool. For each E-DCH throughput value, the E-TFC requiring the lowest Eb/N0 has been kept. The values presented are for a TTI of 10ms since in Alcatel-Lucent UA5.0 release the 2ms TTI for E-DCH is not supported.

Table 4-10: Alcatel-Lucent Node-B performances for E-DCH (HS-DPCCH power included)




4.2.2 COMMON CONTROL CHANNELS TX POWER

The following table shows power offsets relative to the CPICH transmit power for downlink channels CPICH, P-CCPCH, S-CCPCH, PICH, AICH, HS-SCCH, E-AGCH and E-HICH. The transmit power for each channel for BTS maximum output power PA=45W can also be seen on the table.

As explained in 3.2.2, the power for HS-SCCH is used for the computation of HSDPA throughput but ignored in the downlink link budget part of the tool. E-AGCH and E-HICH are taken into account in the downlink link budget when HSUPA is enabled.

Table 4-11: Power offsets for common control channe ls

Remarks concerning HS-SCCH, E-AGCH and E-HICH:

• HS-SCCH: The initial power offset for HS-SCCH is 0dB when HSDPA is activated (otherwise HS-SCCH power is null). However, this value may be changed by the routine that derives HSDPA throughput if the option “Power Control for HS-SCCH” has been activated.

• E-AGCH, E-HICH:

As explained in 3.4.2, the mean transmit power for E-AGCH and E-HICH can be modeled as follows (if HSUPA has been enabled; otherwise power for these channels is null):

With E-AGCH Tx Power being the transmit power for one E-AGCH channel and E-HICH Tx Power the transmit power per signature for one E-HICH channel. In the link budget tool, the following values are applied:

αE-AGCH = 1, nE-HICH = 2

PowerTxHICHEnPowerTxAGCHEPowerTxHSUPADL HICHEAGCHE ⋅+⋅= α




4.2.3 SECTORIZATION

Type: Input

Default value: “Trisectorial”

Values: “Omnisectorial“, “Bisectorial“, “Trisectorial“, “Hexasectorial“.

This input parameter sets the number of sectors per Node-B.

The number of sectors has impact on the UL Frequency Reuse Efficiency variable (see 4.2.4) and the Area Covered per Site result in the uplink link budget part of the tool.

4.2.4 UL FREQUENCY REUSE EFFICIENCY

Type: Variable

Default value: 0.6

Values:

The uplink frequency reuse efficiency FR is defined as follows:

With

• Ii: uplink intra-cell interference, i.e. power received at the Node-B coming from all users in own sector.

• Ie: uplink extra-cell interference, i.e. power received at the Node-B coming from other users.

In the link budget tool, for simplicity reasons, FR depends only on Sectorization (i.e. number of sectors per Node-B).

In a real network however, the uplink frequency reuse efficiency depends on:

• Propagation characteristic and environment (propagation coefficient, standard deviation for variations in air interface path loss).

• Overlapping between cells.

• Number of sectors per user during soft handover process.

Sectorization Omnisectorial Bisectorial Trisectorial Hexasectorial FR 0.71 0.639 0.6 0.5325

ULie

i

II

IFR

+=




4.2.5 DL Ie/Ii Target

Type: Variable

Default value: 190%

Values:

Considering the ratio of DL Ii (i.e. total power coming from the BTS PA of its own sector) to DL Ie (i.e. total power coming from the BTS PA of its other cells/sectors) at cell edge, DL Ie/Ii Target is defined as the value below which above-mentioned ratio must statistically be AR% of the time, when the mobile moves randomly inside the cell.

In the link budget tool, DL Ie/Ii Target value is used in almost every calculation involving downlink interference quantities.

4.2.6 CPICH Ec/I0 Target

Type: Variable

Default value: -15dB

W-CDMA Network Engineering recommends CPICH Ec/I0 Target = -15dB . For more details about the motivation of this value, please refer to [R11].

Area Reliability

85%≤AR<90% 90% 90%<AR≤95%

DL Ie/Ii Target

180% 190% 200%




4.2.7 FEEDERS

Type: Input

Default value: 7/8”

Values: 7/8”, 1–5/8”, “Other”

This input parameter impacts both Rx Cables&Connectors Loss (see 3.1.1) and Tx Cables&Connectors Loss (see 3.2.1).

Above mentioned cables and connectors loss is the total loss (uplink or downlink according to the case considered), existing between the BTS I/O interface and the antenna port.

Cables and connectors loss depends mainly on three characteristics:

• Quality of the feeder: the smaller the diameter of the feeder, the higher the losses.

• Antenna Height: the longer the cable, the higher the losses.

• Frequency: cable loss increases when frequency gets higher.

7/8” feeders are recommended by default because of installation facilities. 1–5/8” feeders should be used in case of antenna height higher than 40 meters.

In the link budget tool, Rx Cables&Connectors Loss and Rx Cables&Connectors Loss are computed as follows for the no-TMA case (logarithmic scale):

With

• Jumper Loss = 0.4dB

• Feeder Attenuation [dB/100m]:

7/8” 1–5/8” Feeder Attenuation [dB/100m] UL DL UL DL

2100MHz (Band I) 5.68 6.01 3.55 3.77

1900MHz (Band II) 5.57 5.70 3.47 3.56

1700MHz (Band III) 5.32 5.49 3.30 3.42

850MHz (Band V) 3.53 3.63 2.13 2.20

Above Feeder Attenuation values were directly extracted or interpolated from [R13]: 7/8” and 1–5/8” Low-Loss Foam Coax.

LossJumpernAttenuatioFeederHeightAntennaLossConnectorsCables ×+×= 2&




In addition, Rx Cables&Connectors Loss and Tx Cables&Connectors Loss values may be input manually by selecting “Other” for the Feeders parameter.

4.2.8 BTS NOISE FIGURE

Type: Input


The typical noise figure for Alcatel-Lucent BTS is 2.5 dB. This quantity does not include feeder, jumpers and connectors losses between BTS I/O interface and the antenna port.

4.2.9 BTS ANTENNA GAIN

Type: Input

Default value: 18dBi

4.2.10 BTS MAXIMUM TX POWER PER SECTOR (PA)

Type: Input

Default value: 45W

BTS maximum output power per sector and per UMTS 5MHz carrier.

The reference point is taken at power amplifier output.

4.2.11 DIVERSITY

Type: Input

Default value: “Polarization” with Polarization Type = ”X Polar”

Values: “No Diversity”, “Polarization”, “Space”

This item impacts the Slant Loss value (see 3.1.1) as follows:

Slant Loss

“No Diversity” “Polarization”

Dense Urban, Urban, Suburban 0 dB 1.5 dB

Rural 0 dB 2.5 dB




4.2.12 TMA

Type: Input

Default value: No

Values: Yes/No

The checkbox “Use of Tower-Mounted Amplifier (TMA)” may be used to take into account the effect of a TMA.

This parameter impacts Rx Cables&Connectors Loss and Tx Cables&Connectors Loss values as follows:

No TMA Use of TMA

Rx Cables&Connectors Loss x 0.4dB

Tx Cables&Connectors Loss y y + 0.4dB + 0.4dB

If a TMA is used, BTS Rx Cables&Connectors Loss is reduced to 0,4dB independently to its original value. On the other hand, Rx Cables&Connectors Loss is increased by 0,8dB due to TMA insertion loss.

Basically, TMA usage depends on the type of limitation for the network: coverage or interference. In suburban and rural environments, which are often coverage-limited, TMA usage is recommended. In urban and interference-limited environments, TMA is not recommended.




4.3. USER EQUIPMENT (UE)

Figure 4-4: User Equipment

4.3.1 Eb/N0 Values

Since the mobile performances vary with manufacturers and models, an assumption must be made concerning UE Eb/N0 Target values.

UE Eb/N0 values are needed for the downlink link budget part of the tool.

UE Eb/N0 values are assumed equal to the BTS Eb/N0 values of 4.2.1.R'99 minus a 3dB loss due in part to the lack of reception diversity for the mobile.

4.3.2 UE MAXIMUM TX POWER

Type: Input

Default value: 21dBm

This parameter is the typical UE output power. Even if this parameter depends on manufacturers and models, this figure is recommended for macro-cell environments as it meets most of the radiation and battery saving requirements. Please refer to [R4] for further details.

4.3.3 UE NOISE FIGURE

Type: Variable

Default value: 7dB

Values:

• 1700, 1900, 2100MHz frequency bands: 7dB

• 850MHz frequency band: 10dB




4.3.4 ACTIVITY FACTOR

Type: Input

Default value: 0.5 for Speech 12.2, 1 for all other services.

See 3.1.3 for details on the motivation for these values.

The specificity of the link budget tool concerning the activity factor is taken into account in UTRAN dimensioning tool UTRAN Dim. Hence, the default values for the activity factor in the link budget tool should not be changed, even when exporting link budget results to UTRAN Dim. Please see [R16] for more information on UTRAN Dim and how it handles the activity factor.

4.3.5 BODY LOSS

Type: Input

Default value: 3dB for Speech 12.2, 1dB for all other services.

Body Loss represents the loss in the signal strength due to the absorption by user’s human body.

For Speech service, the mobile is assumed held by the hand of the user, close to the head.

For data services, the mobile is assumed put on a table.




4.4. QUALITY OF SERVICE (QOS)

Figure 4-5: Quality of Service

4.4.1 BLER TARGET

The Eb/N0 Target values implemented in the link budget tool are:

• Speech: BLER=1%

• CS 64: BLER=0.5%

• PS services: BLER=1%

The power offset βhs for HS-DPCCH has been taken so that BLER=4% on this channel.

4.4.2 AREA RELIABILITY

Type: Input

Default value: 90%

Values: Can be set between 85% and 95%

Quality of service (QoS) can be considered in terms of cell Edge Reliability (ER) or cell Area Reliability (AR).

Cellular system Edge Reliability is defined as the probability that the received signal power level is greater than a threshold all along the cell edge.

Cell Area Reliability is defined as the percentage of locations within the cell in which the received signal level exceeds a certain signal threshold value.

Typical values are 85%, 90% or 95%.




4.4.3 SHADOWING MARGIN

Type: Variable


In ex-Nortel UMTS link budget, the Shadowing Margin is used to compensate time/space-dependent (but not directly dependent to distance from site) losses in the air interface path loss, i.e. shadowing, fast fading and variations in penetration loss. Shadowing Margin is set so that the dimensioning uplink service can be statistically offered to a user moving randomly inside the cell for AR% of the time (AR: Area Reliability). In other words, by taking into account the Shadowing Margin when deriving the Available Reverse Link Budget, the received signal level at the Node-B is made being higher than the required level for the dimensioning uplink service with a probability of AR%.

As seen in 4.1.6, in ex-Nortel UMTS link budget the sum of all the non-deterministic variations in the air interface path loss, i.e shadowing, fast fading and variations in penetration loss is handled as a Log-Normal law of standard deviation σTot.

Concerning the soft handover gain on coverage, in ex-Nortel methodology it is included in Shadowing Margin. Consequently the soft handover gain on coverage is not explicitly mentioned neither in the formulas for uplink or downlink link budget.

Since with HSDPA soft handover is not possible, a multi-server switching gain, which translates the gain obtained by selecting the Node-B able to provide the strongest signal, is used instead of the SHO gain on coverage. By default this gain is taken equal to the SHO gain on coverage (“Perfect Switching” option). In addition, the loss due to a delayed switching can be simulated in the tool by selecting the “Delayed Switching” option. In this case, the multi-server switching gain is taken 1dB lower than the SHO gain on coverage, leading to a 1dB higher Shadowing Margin.

The computation method for the SHO gain on coverage and Shadowing Margin according to AR and σTot follows the principle explained in [R14].

The following table gives the values for Shadowing Margin according to common Area and Edge Reliability values, for default σTot values:

Shadowing Margin [dB] AR

85% ER

85% AR

90% ER

90% AR

95% ER

95%

Dense Urban, Urban, Suburban

σTot = 13.3 dB 2.2 4.38 5.15 7.15 9.46 11.23

Rural σTot =10.2 dB 1.84 4.50 4.33 6.77 7.96 10.11

Table 4-12: Shadowing Margin value according to AR/ER and environment, for UMTS R’99 and HSDPA with perfect switching




4.5. R’99 SPECIFIC SETTINGS

Figure 4-6: R’99 specific settings

4.5.1 MAX. ALLOWED UL NOISE FOR R’99 TRAFFIC

Type: Input

Default value: 3dB

Maximum allowed total Uplink Noise Rise limit applied to R'99 traffic.

- Active even when HSUPA is enabled

- Implemented as rtwpMaxCellLoadNonEdch at NodeB level in Alcatel-Lucent RAN Model (default value=50%, which corresponds an UL Noise Rise of 3.01dB).

This parameter is used in the link budget to compute the Uplink Interference Margin , which role is to compensate interferences generated by other mobiles on the uplink. The Uplink Interference Margin is computed for each uplink service i, so that this service can be received at the Node-B with sufficient SINR even when the network is fully loaded on the uplink.

Below formulas (linear scale) show how the Uplink Interference Margin is computed in the link budget. Please note that user’s own contribution to uplink noise rise has to be removed from the margin.

With User UL Noise Rise(i) being the uplink noise rise received at the Node-B generated by own user when transferring uplink service i.

)(

.)(

iRiseNoiseULUser

RiseNoiseULAllowedMaxiMarginceInterferenUL

−=




This can be rewritten (linear scale):

With:

• UL I0 : total power received at Node-B coming from all users in own and neighboring sectors, plus thermal noise, i.e. UL I0 = UL Ie + UL Ii + NodeB Thermal Noise

• PRx(i): signal strength received at Node-B from the mobile, when transferring uplink service i

Thus the UL Interference Margin in dB is:

In the link budget tool, when HSUPA is disabled, Max. Allowed UL Noise Rise for R’99 traffic is used in above formula.

On the other hand, when HSUPA is enabled, i.e. when “HSUPA enabled” has been checked in the Parameters sheet, Max. Allowed UL Noise Rise for R’99+HSUPA traffics is used in above formula.

1

0

0

0

)(

)(1.

)(1.

.

)(

.)(

−

−+×=

−×=

−=

iPIUL

iPRiseNoiseULAllowedMax

IUL

iPRiseNoiseULAllowedMax

NoiseThNodeB

iP

NoiseThNodeB

IULiMarginceInterferenUL

Rx

Rx

Rx

Rx

1

0)(1.)(

−

+×= iNERiseNoiseULAllowedMaxiMarginceInterferenUL

Target

c

+−= )(1log10.)(0

iNERiseNoiseULAllowedMaxiMarginceInterferenUL

Target

cdBdB

NoiseThNodeB

iP

NoiseThNodeB

IULiMarginceInterferenUL Rx

.

)(

.)( 0 −=




4.5.2 DL POWER RATIO RESERVED FOR R’99 TRAFFIC

Type: Input

Default value: 10%

4.5.3 UL NOISE RISE RESERVED FOR R’99 TRAFFIC

Type: Input

Default value: 0.34dB (10% of the UL Cell Loading corresponding to 6dB Noise Rise)




4.6. HSDPA SPECIFIC SETTINGS

Figure 4-7: HSDPA specific settings

4.6.1 HSDPA UE CATEGORY

HSDPA throughput depends on the channel radio condition, the mobile category and the scheduling algorithm applied.

12 categories of HSDPA mobiles are specified by the 3GPP. The category indicates the maximum number of parallel codes per HS-DSCH (i.e. the maximum number of HS-PDSCH channels that can be decoded simultaneously), the modulations supported, the minimum inter-TTI interval, the maximum number of transport channel bits per TTI, etc. By extension, it indicates the maximum HSDPA throughput achievable for the considered mobile.

The following table summarizes the capabilities of HSDPA mobiles according to the Category:

HSDPA UE

Category

Maximum number of

parallel codes per HS-DSCH

Minimum inter-TTI interval

maximum number of transport

channel bits per TTI

Total number of soft

channel bits

Achievable maximum data rate [Mbps]

1 5 3 7298 19200 1.2 2 5 3 7298 28800 1.2 3 5 2 7298 28800 1.8 4 5 2 7298 38400 1.8 5 5 1 7298 57600 3.6 6 5 1 7298 67200 3.6 7 10 1 14411 115200 7.2 8 10 1 14411 134400 7.2 9 15 1 20251 172800 10.2 10 15 1 27952 172800 14.4 11 5 2 3630 14400 0.9 12 5 1 3630 28800 1.8

Table 4-13: HSDPA UE Categories




Following are presented Alcatel-Lucent CQI tables for HSDPA UE Categories 11/12, 6 and 10. The RLC throughput has been calculated as explained in 3.3.3.Throughput, using the following values:

• RLC SDU size = 320 bits

• MAC-d PDU size = RLC PDU size = 336 bits

• MAC-hs header size = 21 bits

• TTI = 2ms

• BLER 1st transmission = 10%

In the UA5.0 release, MAC-d SDU size is always of 336 bits. Since the Transport Block Size for CQI values lower than 5 is smaller than 336 bits, the throughput would be null for those CQI values, in theory. In order to cope with this problem, in UA5.0 the CQI translated at the Node-B is forced to 5 when the received CQI ranges from 1 to 4, and the transmit power for HS-DSCH is boosted compared to the CQI 5 case. For more details on CQI handling and power offsets for HS-DSCH in UA5.0, please refer to [R15].

CQI TABLE FOR UE CATEGORY 6

CQI value

Transport Block Size

# MAC-d PDU per

Transport Block

RLC throughput @BLER 1st transmission=10%

[kbps]

#HS-PDSCH

channels

Modulation

5 377 1 144 1 QPSK 6 461 1 144 1 QPSK 7 650 1 144 2 QPSK 8 792 2 288 2 QPSK 9 931 2 288 2 QPSK 10 1262 3 432 3 QPSK 11 1483 4 576 3 QPSK 12 1742 5 720 3 QPSK 13 2279 6 864 4 QPSK 14 2583 7 1008 4 QPSK 15 3319 9 1296 5 QPSK 16 3565 10 1440 5 16-QAM 17 4189 12 1728 5 16-QAM 18 4664 13 1872 5 16-QAM 19 5287 15 2160 5 16-QAM 20 5887 17 2448 5 16-QAM 21 6554 19 2736 5 16-QAM 22 7168 21 3024 5 16-QAM 23 7168 21 3024 5 16-QAM 24 7168 21 3024 5 16-QAM 25 7168 21 3024 5 16-QAM 26 7168 21 3024 5 16-QAM 27 7168 21 3024 5 16-QAM 28 7168 21 3024 5 16-QAM 29 7168 21 3024 5 16-QAM 30 7168 21 3024 5 16-QAM




CQI TABLE FOR UE CATEGORY 10

CQI value


# MAC-d PDU per

Transport Block


[kbps]

#HS-PDSCH

channels

Modulation

5 377 1 144 1 QPSK 6 461 1 144 1 QPSK 7 650 1 144 2 QPSK 8 792 2 288 2 QPSK 9 931 2 288 2 QPSK 10 1262 3 432 3 QPSK 11 1483 4 576 3 QPSK 12 1742 5 720 3 QPSK 13 2279 6 864 4 QPSK 14 2583 7 1008 4 QPSK 15 3319 9 1296 5 QPSK 16 3565 10 1440 5 16-QAM 17 4189 12 1728 5 16-QAM 18 4664 13 1872 5 16-QAM 19 5287 15 2160 5 16-QAM 20 5887 17 2448 5 16-QAM 21 6554 19 2736 5 16-QAM 22 7168 21 3024 5 16-QAM 23 9719 28 4032 7 16-QAM 24 11418 33 4752 8 16-QAM 25 14411 42 6048 10 16-QAM 26 17237 51 7344 12 16-QAM 27 21754 64 9216 15 16-QAM 28 23370 69 9936 15 16-QAM 29 24222 72 10368 15 16-QAM 30 25558 76 10944 15 16-QAM




CQI TABLE FOR UE CATEGORY 11 AND 12

CQI value


# MAC-d PDU per

Transport Block


[kbps]

#HS-PDSCH

channels

Modulation

5 377 1 144 1 QPSK 6 461 1 144 1 QPSK 7 650 1 144 2 QPSK 8 792 2 288 2 QPSK 9 931 2 288 2 QPSK 10 1262 3 432 3 QPSK 11 1483 4 576 3 QPSK 12 1742 5 720 3 QPSK 13 2279 6 864 4 QPSK 14 2583 7 1008 4 QPSK 15 3319 9 1296 5 QPSK 16 3440 10 1440 5 QPSK 17 3440 10 1440 5 QPSK 18 3440 10 1440 5 QPSK 19 3440 10 1440 5 QPSK 20 3440 10 1440 5 QPSK 21 3440 10 1440 5 QPSK 22 3440 10 1440 5 QPSK 23 3440 10 1440 5 QPSK 24 3440 10 1440 5 QPSK 25 3440 10 1440 5 QPSK 26 3440 10 1440 5 QPSK 27 3440 10 1440 5 QPSK 28 3440 10 1440 5 QPSK 29 3440 10 1440 5 QPSK 30 3440 10 1440 5 QPSK




4.6.2 POWER CONTROL FOR HS-SCCH

Type: Input

Default value: No

Values: Yes/No

If this option is activated, the power offset for HS-SCCH (initially set to 0dB relatively to CPICH transmit power) is changed. Indeed, the routine that derives HSDPA throughput will handle power control for HS-SCCH.

The power adjustment depends on the UE category, as indicated in the following table (for further details see [R5]):

CQI Power relative to CPICH Power (dB) 1 – 7 0 8 – 9 -3

10 – 12 -5 13 – 30 -8

Table 4-14: HS-SCCH Power Control




4.7. HSUPA SPECIFIC SETTINGS

Figure 4-8: HSUPA specific settings

4.7.1 MAX. ALLOWED NOISE RISE FOR R’99+HSUPA TRAFFICS

Type: Input

Default value: 6dB

Maximum total UL Noise Rise allowed (for R'99+HSUPA traffic) when HSUPA is enabled.

- Active only when HSUPA is enabled

- Default value is 6dB

- Implemented as totalRotMax at RNC level in Alcatel-Lucent RAN Model (default value=6dB)




5. ABBREVIATIONS AND DEFINITIONS

5.1. ABBREVIATIONS

AF: Activity Factor

BTS: Base Transceiver Station

CQI: Channel Quality Indicator

DCH: Dedicated Channel

DL: Downlink

E-AGCH: E-DCH Absolute Grant Channel

E-DCH: Enhanced Dedicated uplink transport Channel

E-DPCCH: E-DCH Dedicated Physical Control Channel

E-DPDCH: E-DCH Dedicated Physical Data Channel

E-HICH: E-DCH HARQ Channel

E-RGCH: E-DCH Relative Grant Channel

E-TFC: E-DCH Transport Format Combination

HARQ: Hybrid Automatic Repeat Request

HSDPA: High Speed Downlink Packet Access

HSUPA: High Speed Downlink Packet Access

HS-DPCCH: High Speed Dedicated Physical Control Channel

HS-DSCH: High Speed Downlink Shared Channel

HS-PDSCH: High Speed Physical Downlink Shared Channel

HS-SCCH: High Speed Shared Control Channel

MPO: Measurement Power Offset

Node-B: see BTS

PG: Processing Gain

PLM: Product Line Management

RFI: Request for Information

RFQ: Request for Quotation

SHO: Soft Handover

UE: User Equipment

UL: Uplink




5.2. DEFINITIONS

Available Reverse Link Budget:

Uplink Maximum Allowable isotropic Path Loss from which engineering margins have been subtracted. Hence, Available Reverse Link Budget is smaller than UL MAPL.

Downlink Maximum Total Path Loss:

Downlink path loss from the BTS Power Amplifier (BTS PA) to a mobile at the cell edge. Does include Tx cables and connectors loss.

Forward Link Required Power:

Transmit power required for the BTS to transmit a specific downlink service to a mobile located at the cell edge.

Maximum Coverage Range:

Also called cell range or cell edge, it is the maximum cell radius for which a mobile moving randomly inside the cell can benefit from a specific uplink service statistically Area Reliability percent of the time.

HSDPA Single User Sector Throughput:

Downlink average throughput assuming one single mobile transferring an unlimited amount of data using HSDPA and moving randomly inside the cell. Coexistence of downlink R’99 traffic on the same sector may be considered though.

HSUPA Single User Sector Throughput:

Similar to HSDPA Single User Sector Throughput (HSUPA, uplink).

Uplink Maximum Allowable isotropic Path Loss (UL MA PL):

Maximum air interface path loss that can be allowed taking into account the mobile maximum output power, Node-B performances (i.e. Eb/N0 Target values) and other environment parameters.

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