01 WR_DC3011_E01_0 ZXWR RNC Dimensioning-35.pdf

ZXWR RNC (U9.3)

Dimensioning Principle

ZTE CORPORATION

ZTE Plaza, Keji Road South, Hi-Tech Industrial Park,

Nanshan District, Shenzhen, P. R. China

518057 Tel: (86) 755 26771900 800-9830-9830

Fax: (86) 755 26772236 URL: http://support.zte.com.cn

E-mail: [email protected]

Contents

Chapter 1 ......................................................................... 1

Introduction .................................................................... 1

Transmission Interfaces of the UTRAN Network ................... 1

Dimensioning Guidelines ................................................... 2

Chapter 2 ......................................................................... 3

Detailed Bandwidth Calculation Methods for the UTRAN Interface .......................................................................... 3

Iub Interface ................................................................... 3

Iu/Iur Interface ............................................................... 4

Calculation of Intermediate Parameters .............................. 4

Overhead Bearing Parameters ........................................... 5

Case Study ..................................................................... 7

Traffic Modeling ..................................................................... 7

Iub Interface Calculation ......................................................... 8

Iu/Iur Interface Calculation ................................................... 14

Case Summary .................................................................... 17

Chapter 3 ....................................................................... 19

Simplified Bandwidth Calculation Methods for the UTRAN Interface ........................................................................ 19

Traffic Profile ................................................................. 19

Transmission Type ......................................................... 19

Default Parameters ........................................................ 20

Interface dimensioning ................................................... 21

General Description .............................................................. 21

Iub Interface ....................................................................... 21

Iu Interface ......................................................................... 22

Iur Interface ........................................................................ 23

Chapter 4 ....................................................................... 25

RNC Hardware Dimensioning ........................................ 25

RNC Product Overview .................................................... 25

RNC Hardware Dimension ............................................... 26

Processing Boards ................................................................ 26

Interface Boards .................................................................. 28

Auxiliary Boards .................................................................. 28

Chapter 5 ....................................................................... 31

Summary ....................................................................... 31

Confidential and Proprietary Information of ZTE CORPORATION 1

C h a p t e r 1

Introduction

Transmission Interfaces of the UTRAN Network

As shown in the figure above, interfaces of the UTRAN network

include:

Iub interface: the interface between Node B and RNs, interface

types include E1(IMA/MLPPP), N×E1(IMA/MLPPP) and

STM-1(ATM), FE/GE, etc.;

Iur interface: the interface between RNCs, interface types include

STM-1(ATM) and FE/GE, etc.;

Iu-CS interface: the CS interface between RNC and MSC, interface

types include STM-1(ATM) and FE/GE, etc.;

Iu-PS interface: the PS interface between RNC and SGSN,

interface types include STM-1(ATM) and FE/GE, etc.;

ZXWR RNC (U9.3) Dimensioning Principl

2 Confidential and Proprietary Information of ZTE CORPORATION

Dimensioning Guidelines The document describes the dimensioning guidelines for ZTE RNC.

It provides methodology for ZTE RNC and Iub/Iu interface

dimensioning.

The RNC dimensioning follows the process shown in the following

figure.

The UTRAN Dimensioning needs the inputs of Service profile,

Transmission Type and Equipment Capability. With these inputs,

the equipment configuration of RNC and each interface bandwidth

can be calculated based on the methodology introduced in this

document.

The 2nd chapter introduces Traffic Service Profile which is the

dimensioning inputs. These parameters could be divided into two

parts, the first table is User Plane Related Inputs, and second one

is Control Plane Related Inputs.

The 3rd chapter is interface bandwidth dimensioning which is

followed service profile and transmission type. As defined in 3GPP,

there are two options for the UTRAN transmission network. For the

same service profile, the bandwidth required in the transmission

network is diversity, according to different transmission overhead.

The 4th chapter is equipment dimensioning, introducing how the

RNC configuration is dimensioned and how the equipment is

configured to meet the requirements of the Operator.


C h a p t e r 2

Detailed Bandwidth Calculation Methods for the UTRAN Interface

Iub Interface BIub = BIubData + BIubSig

� BIubData =

((TCS/(1-CIubCS)+TVS/(1-CIubVS)+TPS/(1-CIubPS))*(1+RI

ub)+ THS/(1-CIubPS))/Relay

� BIubSig = BIubUuSig + BIubNBAPSig

� BIubUuSig =

(((ECS+EVS+EPS)*(1+RIub)+EHS)*VRRC+NC*Vcom)/(1

-CIubUuSig)/1000/Relay

� BIubNBAPSig =

N*(B_IubNcpSig_U+B_IubCcpSig_U+B_IubAlcapSig_U)/(

1-CIubNBAPSig)/Relay/1000/1000

Parameter description:

� BIub: the bandwidth of Iub interface

� BIubData: the User Plane bandwidth of Iub interface

� TCS/TVS/TPS/THS: the net data throughput of the

CS12.2K/CS64K/PS/HS service

� CIubCS/CIubVS/CiubPS: the proportion of the overhead when

Iub interface bears the CS12.2K/CS64K/PS service

� BIubSig: the Control Plane bandwidth of Iub interface

� ECS/EVS/EPS/EHS: the traffic throughput of the

CS12.2K/CS64K/PS/HS service

� VRRC: RRC signaling rate;NC: cell number; Vcom: the

average throughput of common channel per cell



� N: user number

� B_IubNcpSig_U/B_IubCcpSig_U/B_IubAlcapSig_U: the

average NCP/CCP/ALCAP signaling throughput of Iub interface

per user

� CIubUuSig/CIubNBAPSig: the proportion of the overhead

when Iub interface bears the Uu interface signaling and the

NBAP signaling

� RIub: the factor of macro diversity’s influence on Iub

interface’s throughput

� Relay: the redundancy factor for calculating each interface’s throughput

Iu/Iur Interface BIuCS = BIuCSData + BIuCSSig

� BIuCSData = (TCS/(1-CIuCS)+TVS/(1-CIuVS))/Relay

� BIuCSSig =

N*B_IuCSSig_U/(1-CIu_IurSig)/Relay/1000/1000

BIuPS = BIuPSData + BIuPSSig

� BIuPSData = TPS/(1-CIuPS)/Relay

� BIuPSSig = N*B_IuPSSig_U/(1-CIu_IurSig)/Relay/1000/1000

BIur = BIurData + BIurSig

� BIurData = BIubData/(1+RIub)*RIur

� BIurSig = N*B_IurSig_U/(1-CIu_IurSig)/Relay/1000/1000

Description on parameters in the formula:

� BIuCS/BIuPS/BIur: the bandwidth of IuCS/IuPS/Iur interface;

� B_IuCSSig_U/B_IuPSSig_U/B_IurSig_U: the average

IuCS/IuPS/Iur interface signaling throughput per user

� CIuCS/CIuVS/CIuPS/CIu_IurSig: the proportion of the

overhead when the interface bears its corresponding service

� RIur: the factor of macro diversity’s influence on Iur interface’s

throughput

Calculation of Intermediate Parameters TCS (the net data throughput of the CS12.2K service) = ECS*η*12.2/1000

� ECS: the busy hour traffic of the CS12.2k service

Chapter 2 Detailed Bandwidth Calculation Methods for the UTRAN Interface


� η: Voice activity factor, not adopting the mute frame concept;

the direct valuation indicates discontinuous unidirectional

transmission; the value range: 0.4 to 0.9

TVS (the net data throughput of the CS64K service) =

EVS*64/1000

� EVS: the busy hour traffic of the CS64k service

TPS (the net data throughput of the PS service in downlink) =

N*Rd*Vu/1000/1000

� Vu: the average bidirectional R99 data throughput per user

� Rd: the rate of downlink data in the R99 service

THS (the net data throughput of the HS service in downlink) =

N*Rd_HS*Vu_HS/1000/1000

� Vu_HS: the average bidirectional HS data throughput per user

� Rd_HS: the rate of downlink data in the HS service

EIub_Sig_U/EIuCS_Sig_U/EIuPS_Sig_U/EIur_Sig_U = single user

signaling model× signaling length (or directly adopting estimated

value, 1-2 bps for Iu interface per user, and 3-5 bps for Iub

interface per user)

Overhead Bearing Parameters Overhead Bearing Parameters

Paramet

ers

Typic

al

mess

age

lengt

h

(byte

)

User

Plan

e

head

er

(byt

e)

Transmission

header (byte)

TOH

(Transmission overhead) (％％％％)

AT

M

PP

P

Et

hernet

AT

M

PPP Ethern

et

Iub

interface

TOH of

the voice

service

32 7 9 13 66 33

%

38

%

70%

Iub

interface

TOH of

the CS64

service

160 5 36 13 66 20

%

10

%

31%

Iub

interface

TOH of

the PS

480 14 10

4

13 66 20

%

5% 14%



Paramet

ers

Typic

al

mess

age

lengt

h

(byte

)

User

Plan

e

head

er

(byt

e)

Transmission

header (byte)

TOH


AT

M

PP

P

Et

hernet

AT

M

PPP Ethern

et

service

IuCS

interface

TOH of

the voice

service

32 4 9 25 78 29

%

48

%

72%

IuCS

interface

TOH of

the CS64

service

80 0 18 25 78 18

%

24

%

49%

IuPS

interface

TOH of

the PS

service

480 12 84 13 66 17

%

5% 14%

Iur

interface

TOH of

the voice

service

32 7 9 13 66 33

%

38

%

70%

Iur

interface

TOH of

the CS64

service

160 5 36 13 66 20

%

10

%

31%

Iur

interface

TOH of

the PS

service

480 14 10

4

13 66 20

%

5% 14%

Iub

interface

Uu

signaling

TOH

40 6 18 13 66 38

%

32

%

64%

Iub

interface

NBAP

signaling

TOH

256 69 41 86 21

%

14

%

25%

Iu

interface

RANAP

signaling

TOH

256 84 68 113 25

%

21

%

31%



Paramet

ers

Typic

al

mess

age

lengt

h

(byte

)

User

Plan

e

head

er

(byt

e)

Transmission

header (byte)

TOH


AT

M

PP

P

Et

hernet

AT

M

PPP Ethern

et

Iur

interface

RNSAP

signaling

TOH

256 84 68 113 25

%

21

%

31%

Case Study Calculate the bandwidth of each interface in various transmission

modes with the data of a supposed traffic model and the

bandwidth formula mentioned in Chapter 1.

Traffic Modeling

User number: 3,000,000

Site number: 2,000

Cell number: 6,000

Busy hour voice traffic per user: 0.03 Erl

Busy hour visual telephone traffic per user: 0.003 Erl

Busy hour comprehensive BHCA per user: 6

Busy hour downlink data throughput per user: 2,079

Busy hour uplink data throughput per user: 520

Voice activity factor: 0.6

Soft handover ratio: 30％ Redundancy factor of interface throughput: 70％ The influence factor of Iub interface’s macro diversity on the data

throughput: 18％ Ratio of Iur interface throughput to Iub interface throughput: 9％

Suppose there are 10 RNCs, in each RNC:

User number: 300,000

NodeB number: 200

Cell number: 600



Average user number on each Node B: 1,500

(This document mainly explains the transmission bandwidth

calculation. To simplify the calculation, all are equally distributed

here.)

(To simplify the computation, in the assumption, the data service

is not subdivided into R99 data service and HS data service, which

does not affect the interface’s throughput much. If the subdivision

is needed, refer to Chapter 4 for subdivision. The only difference is

that the R99 data service needs to consider the macro diversity

factor at Iub interface, yet the HS service needs not.)

Iub Interface Calculation

All Adopting Traditional Transmission Network

Description on Scenario 1:

Iub interface adopts the E1-IMA-ATM mode. RNC and NodeB

interact based on the ATM technology, and access the

transmission network in the E1-IMA mode.

Bandwidth calculation under Scenario 1:

1) Calculating the transmission requirements of each NodeB:

The bandwidth for Uu interface signaling:

B_IubUuSig =

(E_CS+E_VS+E_PS)*V_RRC*(1+R_Iub)/(1-C_IubUuSig)/1000/

Relay = (1500 × 0.03+1500 ×0.003+2079×1500/1000/64)×3.4×(1+0.18)/(1-38%)/1000/0.7

= 0.91 Mbps

The bandwidth for common channel signaling:

B_IubComSig = NC×V_COM/(1-C_IubUuSig)/1000/Relay = 3×24

/ (1-38%) / 1000/0.7 = 0.17 Mbps

The bandwidth for Iub interface NBAP signaling:

B_IubNBAPSig = N×(B_IubNcpSig_U+B_IubCcpSig_U)/1000 /

(1-C_IubNBAPSig) /1000/Relay = 1500×(4.9+3.7) /1000 /

(1-21%)/1000/0.7=0.02 Mbps

SDH Network



The bandwidth for Iub interface ALCAP signaling:

B_IubAlcapSig =

N*B_IubAlcapSig_U/1000/(1-C_IubNBAPSig)/1000/Relay = 1500×5.64/1000/ (1-21%)/1000/0.7= 0.02 Mbps

The total bandwidth for Iub interface signaling under each NodeB

averagely:

B_IubSig = B_IubUuSig + B_IubNBAPSig + B_IubComSig +

B_IubAlcapSig = 1.12 Mbps

The bandwidth for Iub interface CS service:

B_IubCS =

(TCS/(1-C_IubCS)+TVS/(1-C_IubVS))*(1+R_Iub)/Relay =

(1500 × 0.03 × 12.2 × 0.6/(1-33%)/1000+1500 × 0.003 ×64/(1-20%)/1000)×(1+0.18)/0.7 = 1.43 Mbps

The bandwidth for Iub interface PS service:

B_IubPS=TPS/(1-C_IubPS)×(1+R_Iub)/Relay=1500 ×2079/1000/1000/(1-20%)×(1+0.18)/0.7 = 6.57 Mbps

The total bandwidth for Iub interface service under each NodeB

averagely:

B_IubData = B_IubCS + B_IubPS = 8 Mbps

The total bandwidth of Iub interface under each NodeB averagely:

B_Iub = B_IubSig + B_IubData = 9.12 Mbps

In this scenario, all data throughput is through E1, so each NodeB

needs 9.21/1.92 = 5 E1s

(9.21M is the bandwidth that has taken the redundancy into

account, 1.92 is adopted in view that 30 timeslots are applied in

actual transmission.)


Iub interface adopts the E1-PPP-IP mode. RNC and NodeB interact

based on the IP technology, and access the transmission network

in the E1-IMA mode.

The only difference between Scenario 1 and Scenario 2 is the

overhead factor. For the specific values, refer to Section 4.4.

SDH Network



The transmission requirements of each NodeB in Scenario 2 can be

calculated with the corresponding overhead factor:


B_IubUuSig = 0.82 Mbps


B_IubComSig = 0.15 Mbps


B_IubNBAPSig = 0.02 Mbps


B_IubAlcapSig = 0 (no ALCAP overhead in the IP bearing mode)


averagely:


B_IubAlcapSig = 1 Mbps


B_IubCS = 1.44 Mbps


B_IubPS = 5.55 Mbps

The total bandwidth for Iub interface data under each NodeB

averagely:

B_IubData = B_IubCS + B_IubPS = 7 Mbps


B_Iub = B_IubSig + B_IubData = 8 Mbps

In this scenario, each NodeB needs 8/1.92 = 5 E1s

(Compared with the ATM UTRAN, though it also needs five E1s, its

bandwidth is smaller and the redundancy is greater since it adopts

the IP UTRAN mode.)

All Adopting IP Transmission Network

Scenario description:

Iub interface adopts the FE/GE mode. RNC and NodeB interact

based on the IP technology, and access the transmission network

in the FE/GE mode.



The difference of this scenario is still the overhead factor. For

specific values, refer to section 4.4.

The transmission bandwidth of each NodeB in this scenario can be

calculated with the corresponding overhead factor:








B_IubAlcapSig = 0 (no ALCAP overhead in the IP bearing mode)


averagely:




B_IubCS = 2.52 Mbps


B_IubPS = 6.13 Mbps

The total bandwidth for Iub interface data under each NodeB

averagely:

B_IubData = B_IubCS + B_IubPS = 8.65 Mbps


B_Iub = B_IubSig + B_IubData = 10.52 Mbps

In this scenario, the bandwidth of each NodeB is 10.52 Mbps, and

one FE interface is needed.

Explanation:

IP Transmission

Network



Since the overhead of the Ethernet header is relatively large, the

total bandwidth is comparatively great. However, since the IP

network can be multiplexed, the backbone network pressure is

much smaller compared with the fixed resource occupation of SDH

network. Therefore, the PS service can be transmitted through the

IP network.

The following calculates the bandwidth in shunt conditions.

Adopting Traditional Transmission Network and IP Transmission Network Simultaneously


The CS service and signaling adopt the E1-IMA-ATM mode. For the

CS service and signaling, RNC and NodeB interact based on the

ATM technology, and access the traditional transmission network

in the E1-IMA mode.

The PS service adopts the FE/GE mode. For the PS service, RNC

and NodeB interact based on the IP technology, and access the IP

transmission network in the FE/GE mode.

The calculation method is the same as that mentioned above.

Different overhead factors are adopted in the calculation for

different bearing modes.





The bandwidth of Iub interface NBAP signaling:





averagely:

SDH Transmission

Network

IP Transmission

Network






B_IubCS = 1.44 Mbps

For the SDH network, the total bandwidth of Iub interface under

each NodeB averagely:

B_IubData = B_IubCS + B_IubSig = 2.53 Mbps


B_IubPS = 6.13 Mbps

For the IP network, the total bandwidth of Iub interface under each

NodeB averagely:

B_Iub = B_IubPS = 6.13 Mbps

In this scenario, the transmission requirements of each NodeB are

as below:

For the SDH network: 2.53 Mbps, two E1 interfaces

For the IP network: 6.13 Mbps, one FE interface


RNC and NodeB interact based on the IP technology. The CS

service and signaling adopt the E1-PPP-IP mode, and access the

traditional transmission network in the E1-PPP mode. The PS

service adopts the FE/GE mode, and access the IP transmission

network in the FE/GE mode.

Compared with the above scenario, the PS part is basically the

same, and the overhead of the CS part is slightly different.






SDH Transmission

Network

IP Transmission

Network





B_IubAlcapSig = 0


averagely:




B_IubCS = 1.44 Mbps

For the SDH network, the total bandwidth of Iub interface under

each NodeB averagely:

B_IubData = B_IubCS + B_IubSig = 2.43 Mbps


B_IubPS = 6.13 Mbps

For the IP network, the total bandwidth of Iub interface under each

NodeB averagely:

B_Iub = B_IubPS = 6.13 Mbps

In this scenario, the transmission requirements of each NodeB are

as below:

for the SDH network: 2.43 Mbps, two E1 interfaces

for the IP network: 6.13 Mbps, one FE interface

Iu/Iur Interface Calculation

In this case, suppose there are 10 RNCs, and each RNC has

300,000 users, 200 NodeBs, and 600 cells. The transmission

requirements of Iu/Iur interface in each RNC are as belows.

Adopting Traditional Transmission Network

The total bandwidth for IuCS interface data:

B_IuCSData=(TCS/(1-C_IuCS)+TVS/(1-C_IuVS))/Relay

=(300000×0.03×12.2×0.6/1000/(1-29%) +300000×0.003×64/1000/(1-18%))/0.7 = 232.9 Mbps

The total bandwidth for IuCS interface signaling:

B_IuCSSig=N×B_IuCSSig_U/(1-C_Iu_IurSig)/Relay/1000/1000

= 300000×1.23 / (1- 25%) /0.7/1000/1000 = 0.7 Mbps

The total bandwidth for IuPS interface data:



B_IuPSData=TPS/(1-C_IuPS)/Relay= 300000 ×2079/1000/1000/(1-17%)/0.7 = 1073.5M

The total bandwidth for IuPS interface signaling:

B_IuPSSig=N×B_IuPSSig_U/(1-C_Iu_IurSig)/Relay/1000/1000

= 300000×0.91/(1-25%)/0.7/1000/1000 = 0.52 Mbps

The total bandwidth of Iu interface:

B_Iu = B_IuCSData+B_IuCSSig+B_IuPSData+B_IuPSSig =

1307.6 Mbps

The bandwidth of Iur interface:

B_IurData = B_IubData/(1+R_Iub)*R_Iur = 200×8/(1+0.18)×0.09 = 122 Mbps

B_IurSig=N*B_IurSig_U/(1-C_Iu_IurSig)/Relay/1000/1000=300

000×0.776/(1-25%)/0.7/1000/1000 =0.44 Mbps

B_Iur = B_IurData+B_IurSig = 122.44 Mbps

Suppose the transmission throughput of STM-1 interface is 140

Mbps. In this scenario, the interface requirements of each RNC are

as below:

For IuCS, it needs (232.9+0.7) /140 = two STM-1 interfaces;

For IuPS, it needs (1073.5+0.52) /140 = eight STM-1 interfaces;

For Iur, it needs 122.44/140 = one STM-1 interface.

Adopting IP Transmission Network

Compared with the ATM bearing, the calculation process is the

same, and only the overhead is different. The bandwidth

requirements of each interface are as below:


B_IuCSData = 497.8 Mbps


B_IuCSSig = 0.8 Mbps

The total bandwidth for IuPS data:

B_IuPSData = 1035.9 Mbps


B_IuPSSig = 0.6 Mbps


B_Iu = B_IuCSData+B_IuCSSig+B_IuPSData+B_IuPSSig = 1535

Mbps




B_IurData = B_IubData/(1+R_Iub)*R_Iur = 200×8.65/(1+0.18)×0.09 = 132 Mbps B_IurSig=N*B_IurSig_U/(1-C_Iu_IurSig)/Relay/1000/1000 =

300000×0.776/(1-31%)/0.7/1000/1000 =0.5 Mbps


Suppose CN/RNC adopts GE interface in connection and the

transmission throughput of GE interface is 800 Mbps. In this

scenario, the interface requirements of each RNC are as below:

for IuCS, it needs (497.8+0.8) /800 = one GE interface;

for IuPS, it needs (1035.9+0.6) /800 = two GE interfaces;

for Iur, it needs 132.5/800 = one GE interface

Shunt Transmission

IuCS interface and Iur interface adopt the STM-1 for transmission,

and IuPS interface adopts GE interface for transmission.


B_IuCSData = 232.9 Mbps


B_IuCSSig = 0.7 Mbps

The total bandwidth for IuPS interface data:

B_IuPSData = 1035.9 Mbps


B_IuPSSig = 0.6 Mbps


B_Iu = B_IuCSData+B_IuCSSig+B_IuPSData+B_IuPSSig = 1270

Mbps


B_IurData = B_IubData/(1+R_Iub)*R_Iur = 200×8/(1+0.18)×0.09 = 122 Mbps

B_IurSig=N*B_IurSig_U/(1-C_Iu_IurSig)/Relay/1000/1000=300

000×0.776/(1-25%)/0.7/1000/1000 =0.44 Mbps


In this scenario, the interface requirements of each RNC are as

below:

for IuCS, it needs (232.9+0.7) /140 = two STM-1 interfaces;

for IuPS, it needs (1035.9+0.6) /140 = two GE interfaces;

for Iur, it needs 122.44/140 = one STM-1 interface



Case Summary

According to the case study above, the transmission bandwidth is

related to the user number of NodeB or RNC, service model,

interface type and bearing mode.

In this case, through assumption, the user number and service

model are set, and the bandwidth of different interfaces in

different bearing mode is deduced accordingly, as shown in the

table below.

(For Iub interface, the same color represents the corresponding

connection mode of RNC and NodeB.)

NE Interfac

e

Interface

Type

Bandwidth

Requirement

s (Mbps)

Interface

Requirement

s

Node

B

Iub E1 (IMA) 9.12 5 E1

E1 (PPP) 8 5 E1

FE 10.52 1 FE

E1 (IMA) for CS

FE for PS

2.53+6.13 2 E1+1 FE

E1 (PPP) for CS

FE for PS

2.43+6.13 2 E1+1 FE

RNC Iub E1 (IMA) Converging E1

of NodeB

1000 E1

CSTM-1

(E1-IMA)

Converging E1

of NodeB

17 CSTM-1

E1 (PPP) Converging E1

of NodeB

1000 E1

CSTM-1

(E1-PPP)

Converging E1

of NodeB

17 CSTM-1

GE Converging

the bandwidth

of NodeB,

2104

3 GE

E1(IMA) for CS

GE for PS

CS converging

E1 of NodeB;

PS converging

the bandwidth

of NodeB,

1226

400 E1+2 GE

CSTM-1(E1-IMA

) for CS

GE for PS

CS converging

E1 of NodeB;

PS converging

the bandwidth

of NodeB,

1226

7 CSTM-1+ 2

GE

E1(PPP) for CS CS converging

E1 of NodeB;

400 E1+2 GE



NE Interfac

e

Interface

Type

Bandwidth

Requirement

s (Mbps)

Interface

Requirement

s

GE for PS PS converging

the bandwidth

of NodeB,

1226

CSTM-1(E1-PPP

) for CS

GE for PS

CS converging

E1 of NodeB;

PS converging

the bandwidth

of NodeB,

1226

7 CSTM-1+ 2

GE

IuCS STM-1 233.6 2 STM-1

GE 498.6 1 GE

IuPS STM-1 1074 8 STM-1

GE 1036.5 2 GE

Iur STM-1 122.4 1 STM-1

GE 132.5 1 GE


C h a p t e r 3

Simplified Bandwidth Calculation Methods for the UTRAN Interface

Traffic Profile The UTRAN RAN Dimensioning is based on the Traffic Profile from

the Operator. The following is the minimum requirements for the

RNC dimensioning, and can be considered as the input of the

dimensioning.

Traffic Model

Parameters provided by operators Value

CS call service (Erl, voice and video)

PS throughput ( Mbps, UL + DL)

RNC Number

Cell Number

NodeB Number

Transmission Type According to the requirement from operator, the transmission

interface type for RNC is listed in the table below:

Transmission Type

Item Value

Iub Interface



Item Value

Iu-CS Interface

Iu-PS Interface

Iur Interface

Default Parameters The parameters mentioned here always could be provided by

operators， if we do not have these materials, our default

parameters can be set as below:

Default Parameters

Default Parameters Default Value

Soft handover ratio for R99 service 18%

RNC processing capability utilization 90%

Interface utilization 80%

Iur ratio vs Iub interface 9%

Ratio of sig. vs service 10%

Ratio of downlink service 80%

Common sig. throughput of each cell 24 kbps

Notes:

Soft handover is also called Macro Diversity in Iub interface. Here

default value is 18% (not include softer handover).

RNC processing capability redundancy is also required in case that

the Operator wants the RNC to be configured a little larger to avoid

the System’s Peak.

The default interface utilization is 80%.

For the Iur interface dimensioning, the bandwidth is considered as

a ratio of Iub bandwidth. The default value is 9%.

For sig. Interface dimensioning, the bandwidth is considered as a

ratio of service bandwidth. The default value is 10%.

Sometimes the data throughput requirement given by the

Operator is a total data throughput. In this case, generally ZTE will

give an assumption that the downlink data throughput is 80% of

the total data throughput.

Chapter 3 Simplified Bandwidth Calculation Methods for the UTRAN Interface


Interface dimensioning

General Description

There are two options(ATM or IP) for the transmission network in

the UTRAN network, and the transmission overheads for the two

transmission network are different. For the interface bandwidth

dimensioning, the transmission type needs to be discriminated.

The following interface overhead respectively for ATM and IP can

be the inputs of the interface bandwidth dimensioning

Transmission Overhead for ATM and IP

Parameters Transmission overhead

ATM IP

Iub

CS on Iub interface 33% 70%

PS data on Iub interface 20% 14%

Interface signaling on Iub 38% 64%

Iu IuCS interface 29% 72%

IuPS interface 17% 14%

For the PS data service, it contains R99 DCH Packet Domain data

service and HSDPA service. Both of them have the same Overhead

in UTRAN transmission network. In the case R99 and HSDPA are

on hybrid transmission and R99 PS data service and HSDPA

services has different transmission bearer, the transmission

overhead will be different.

Generally the bandwidth is larger in Downlink compared with the

bandwidth in Uplink, so in this document only the bandwidth in

downlink is calculated, and the calculation of Uplink is in a similar

method.

Iub Interface

The bandwidth in Iub interface contains the data throughput in

Control Plane and User Plane.

From the traffic profile, the data throughput requirements for

different service type can be identified. Based on the transmission

type, the overhead needs to be taken into consideration for

different service type data throughput.

Iub interface has to carry not only the user data (voice, video, and

PS) but also control signaling traffic.

The bandwidth of Iub is:



BIub = BIubData + BIubSig

BIub: Bandwidth of Iub interface

BIubData: User data bandwidth of Iub interface, BIubData =

BIubCS+ BIubPS;

BIubSig: Signaling bandwidth of Iub interface, BIubSig=

BIubUuSig + BIubNodeBSig;

Total Traffic Data Throughput

� BIubCS = (CS_voice+ CS_video) *(1+RIub) / (1-CIubCS) /

RelayB

� BIubPS = TPS * Rd *(1+RIub) / (1-CIubPS) / RelayB

In which:

BIubCS: the User Plane bandwidth for Iub interface;

CS_voice/CS_video: CS service traffic throughput.

CIubCS /CIubPS: transmission overhead for CS /PS service;

RIub: Iub interface macro diversity factor;

RelayB: Utilization of interface

TPS: Total Throughput of PS

Rd: Ratio of DL

Total Signal Data Throughput

� BIubUuSig = (BIubCS+BIubPS) × RSig

� BIubNodeBSig = (NC * Vcom ) /(1-CIubSig) / RelayB

In which:

RSig: Signaling percentage of the traffic. Default value is 9%.

NC: Cell number;

Vcom: Average signal data rate for common channel per cell.

Default value is 24kbps.

CIubSig: Transmission overhead for Iub common channel

signaling.

Iu Interface

The Iu interface bandwidth dimensioning contains the bandwidth

in IuCS interface and the bandwidth in IuPS interface.

IuCS Interface

BIuCS = BIuCSData + BIuCSSig

� BIuCSData = (CS_voice+ CS_video)/(1-CIuCS) / RelayB

Chapter 3 Simplified Bandwidth Calculation Methods for the UTRAN Interface


� BIuCSSig = BIuCSData × RSig

In which:

BIuCS: Total bandwidth for IuCS;

CIuCS: the transmission overhead for voice and video calls

services.

BIuCSSig: IuCS interface signaling throughout.

RSig: Signaling percentage of the traffic

IuPS Interface

BIuPS = BIuPSData + BIuPSSig

� BIuPSData = TPS* Rd /(1-CIuPS) / RelayB

� BIuPSSig = BIuPSData × RSig ,

In which:

BIuPS: Total bandwidth for IuPS interface;

TPS: total throughput of Packet data service.

CIuPS: the transmission overhead for Packet data service.

BIuPSSig: IuPS interface signaling throughout.

Rd: Ratio of DL

Iur Interface

The Iur interconnects different RNCs in order to support handover

procedures between two different RNC areas. This specific

handover is called drift handover (DHO). The user data traffic and

signaling traffic is transmitted over the Iur interface. For practical

project experiences, the transmission bandwidth of Iur is set as

the 9% of bandwidth for Iu interface.


C h a p t e r 4

RNC Hardware Dimensioning

RNC Product Overview The RNC system is built in a standard 19-inch cabinet, and the

dimension of height* width* depth is 2000* 600* 800 (mm). The

rack of RNC system and architecture are shown as the following

figures:

ZXWR RNC System Architecture

ZXWR RNC provides three types of shelves. With different

functions, the shelves are named as Control Shelf, Switch Shelf,

and Resource Shelf.

� Control Shelf: responsible for the control plane processing,

O&M processing and clocking.



� Resource Shelf: responsible for the user plane processing and

interface access. It can supports ATM and IP access, and

provides IP route function and IP switch function between

resource processing board and transport board.

� Switch Shelf: provides IP switch platform for the resource

shelves expansion.

It is very easy for shelf expansion according to the traffic increase,

which is shown in the following picture:

ZXWR RNC Capacity Expansion

RNC Hardware Dimension According to the function, there are three kinds of RNC boards,

including processing boards, interface boards and auxiliary

boards,

Processing boards are the most important part in RNC, which is

responsible for the control plane processing and user plane

processing. Interface boards are responsible for the transmission

interface and protocol processing. Auxiliary boards provide system

control, data switch, system operation and maintenance.

Processing Boards

There are two types of processing boards: RCB is used for

processing control plane data and RUB is for user plane data.

One processing unit includes two RCB boards and two RUB boards.

They are dimensioned based on following factors:

1. Cell number

2. NodeB number

3. Erl for CS traffic and data throughput of PS traffic

One processing unit can provide at most 140 NodeB, 420 cell,

4800 Erl for CS traffic or 600 Mbps for PS traffic.

Chapter 4 RNC Hardware Dimensioning


According to the processing unit, the RNC processing ability can be

divided into 16 levels. The processing capacity of the unit and the

unit expansion are listed in the below table:

ZXWR RNC Processing Unit Capacity

Capaci

ty

Level

Configurati

on Processing Ability

RCB RUB NodeB Cell CS (Erl) PS Traffic

( Mbps)

Level 1 2 2 140 420 4800 600

Level 2 4 4 280 840 9600 1200

Level 3 6 6 420 1260 14400 1800 ……… ………… …………………………………… Level

13 26 26 1820 5460 62400 7800

Level

14 28 28 1960 5880 67200 8400

advanc

e Level

1

28 30 1960 5880 72000 9000

advanc

e Level

2

28 32 1960 5880 76800 9600

There are three main limitation factors for the processing unit

dimension. For the configuration, the maximum level must be

chosen from the three factors below:

Unit Level = (NodeB Number) / 140

Unit Level = (Cell Number) / 420

Unit Level = (CS Traffic Erl) / 4800 + (PS Traffic Mbps) / 600

Because of processing level design, ZXWR RNC expansion is based

on the processing unit. The RNC expansion process is just as the

picture:

ZXWR RNC Processing Unit Expansion

RCB is not only responsible for the control plane processing, but

also for the signaling link processing. As the RCB board which is



special for signaling link processing, we also call it RSB (RNC

Signaling Board) in logical function.

The RSB configuration principle is as below:

When it is under processing level 5, one pair of RSB is required.

When it is between processing level 6 and level 10, two pairs of

RSB are required.

When it is between processing level 11 and advance level2, three

pairs of RSB are required.

Interface Boards

ZXWR RNC can provide abundant transmission interface to meet

the operator’s requirement, such as E1, STM-1, CSTM-1, FE and

GE, etc.

DTA/DTI is used to provide E1 interface.

SDTA2/SDTI is used to provide channelized STM-1 interfaces.

APBE/POSI is used to provide STM-1 interfaces.

GIPI4 is used to provide FE/GE interfaces.

The limitation factor for transmission interface board is listed in

the following table:

ZXWR RNC Interface Boards Capacity

Interface

Board Limitation Factor

DTA 32 E1 / 60 NodeB

DTI 32 E1 / 64 NodeB

SDTA2 4 CSTM-1 / 168 NodeB / 310 Mbps (UL or DL)

SDTI 2 CSTM-1 / 64 NodeB / 220 Mbps (UL or DL)

APBE 4 STM-1 / 310 Mbps (UL or DL)

POSI 4 STM-1 / 310 Mbps (UL or DL)

GIPI4

2 GE / 200 NodeB (with 1588) / 1500 Mbps

(UL+DL)

Auxiliary Boards

There are some boards to provide the system control, data switch,

system operation and maintenance, and so on.

ROMB is used to monitor and manage all of the boards in the

system, and to implement the general processing of the system

and route protocol management.

Chapter 4 RNC Hardware Dimensioning


SBCX provides the operation and maintenance management

agent functionality.

CLKG board is responsible for the clock supply and external

synchronization.

THUB is for control plane data switching among different shelves.

UIMC is for the switching function of control plane processing

boards, and clock distribution. Information switching of UIMC

boards in different shelves is implemented by THUB.

GUIM is for the switching function of user plane processing boards.

Information switching of GUIM boards in different shelves is

implemented by GLI and PSN.

GLI and PSN are for user plane data switching among different

resource shelves.

There are two GIPI4 boards which are responsible for NodeB

operation and maintenance.

The configuration principle for auxiliary board is based on the

below table:

ZXWR RNC Auxiliary Board Configuration Principle

Board Name Dimension Principle

ROMB 2 piece per RNC.

SBCX 2 or 3 piece per RNC

CLKG 2 piece per RNC

THUB 2 piece per RNC

UIMC 2 piece per Control Shelf or Switch

Shelf

GUIM 2 piece per Resource Shelf

GIPI4 2 piece for OMCB

GLI 2 piece for every 2 Resource

Shelves

PSN 2 piece per RNC


C h a p t e r 5

Summary

This document is a dimensioning document. It defines the input

for the dimensioning of interface and RNC, and defines the

dimensioning methodology.

For Iub interface bandwidth dimensioning, the total bandwidth

includes User Plane bandwidth and Control Plane bandwidth.

In order to do the dimensioning for the UTRAN equipment and

interface, the first steps is to analysis the traffic profile, and if

possible do some assumption, to get the parameter and its

corresponding value for the dimensioning methodology, and then

use the dimensioning methodology to calculate the UTRAN

equipment configuration and the interface bandwidth.

01 WR_DC3011_E01_0 ZXWR RNC Dimensioning-35.pdf

Documents

macro diversitys influence

busy hour traffic

signaling link processing

common channel signaling

uu interface signaling

packet data service

net data throughput

control plane processing