GSM PPT

GLOBAL SYSTEM OF MOBILE COMMUNICATIONS (GSM)

NETWORK ARCHITECTURE

MSC/VLR

HLR/AUC EIR SC/VM

OMC

BSC

BTSPSTNISDN

PSPDN

MS

BSS

MSS

Um

Abis

BIEA

F

C

H

MSC/VLR

E

GSM900 :

up: 890~915MHz

down: 935~960MHz

duplex interval: 45MHz

bandwidth: 25MHz ，frequency interval: 200KHz

GSM1800 :up: 1710-1785MHz down: 1805-1880MHzduplex interval: 95MHz ，working bandwidth: 75MHz ，frequency interval: 200KHz

EGSM900 :

up: 880~890MHz

down: 925~935MHz

duplex interval: 45MHz

bandwidth: 10MHz ，frequency interval: 200KHz

GSM1900MHz:up:1850~1910MHzdown:1930~1990MHzduplex interval: 80MHz ，working bandwidth: 60MHz ，frequency interval: 200KHz

Allocated GSM Frequency Bands

GSM ENTITIES

VLR dynamically stores subscriber information needed to handle incoming/outgoing calls Manages the mobile subscribers database HLR

holds all the switching functions manages the necessary radio resources MSC

AUC/EIR Authentication Center(s) (AUC)Handling Mobile Station Equipment Identity

Equipment used by mobile service subscribers for access to services.

MS

INTERFACES

MS

Ate r interfac e

Um interface

BSC

BIE

BTS

BIE

Abisinterface

SM SM TC

A interfa ce

MSC

OMC

Q3 interface

Fig.1-3 BSS Structure

•Voice conversion

16kbit/s RPE-LTP 64kbit/s A-law PCM codes.

Typically TC is located between MSC and BSC.

TRAU

Managing Wireless network-BSSMonitoring BTS

Controls:Wireless link distribution between MS and BTSCommunication connection and disconnectionMS location, handover and pagingVoice encoding, transecoding (TC), rate,

adaptation, The operation and maintenance functions of BSS.

BSC

Base Station Controller

Base Transceiver Station (BTS)

Wireless transmissionWireless diversityWireless channel encryptionConversion between wired and wireless signalsFrequency Hopping

BaseBand Unit: voice and data speed adapting and channel codingRF Unit: modulating/demodulating, transmitter and receiverCommon Control Unit: BTS operation and maintenance

GSM Network Entity

BTS

Base Transceiver Station

channel

TCH

CCH

Voice CH

Data CH

FR Voice Traffic Channel (TCH/FS)

HR Traffic Channel (TCH/HS)

4.8Kbit/s HR TCH (TCH/H4.8)

9.6Kbit/s FR TCH(TCH/F9.6)

4.8Kbit/s FR TCH (TCH/F4.8)

BCH

FCCH (down)SCH (down)

BCCH (down)

CCCH

RACH (up)

AGCH (down)

PCH (down)

DCCH

SDCCH

FACCH

SACCH

14.4Kbit/s FR TCH (TCH/F14.4)

Enhanced FR Traffic Channel (TCH/EFR)

CHANNEL SPECIFICATIONS

Small capacity cell with only 1 TRX

TN0: FCCH+SCH+CCCH+BCCH+SDCCH/4(0,_,3)+SACCH/C4(0,_,3);TN1-7: TCH/F+FACCH/F+SACCH/TF

The medium-size cell with 4 TRXs1TN0 group: FCCH+SCH+BCCH+CCCH;

2 SDCCH/8(0,_,7)+SACCH/C8(0,_,7);29 TCH/F+FACCH/F+SACCH/TF

Channel Combinations

Cell Mode Layout

O

Omni-directional cell

Adopt omni-directional antenna ，the overall directional propagation characteristic is the same.

Directional cell

In general, cell with multi-sector is in common use. Every directional cell adopts directional antenna.

Traffic Measurements

Erlang :

the traffic intensity of a totally occupied channel (i.e. the call hour of a unit hour or the call minute of a unit minute). For example, the traffic of a channel occupied for 30 minutes in an hour is 0.5 Erlang)

GOS:

defined as the probability of call blocking or the probability when the call delay time is longer than a given queuing time.

Frequency Hopping

Reason: counteract Rayleigh Fading scatter interference among multiple calls

Types: Base band frequency hopping

keeps the transmission and receiving frequency of each carrier unit unchanged, but merely sends FU transmission data to different carrier units at different FN moments.

radio frequency hopping

controls the frequency synthesizer of each transceiver, making it hop according to different schemes in different time slots.

The multi-path propagation of radio signals causesmagnitude fading and delay time.

Space Diversity (antenna diversity)

Polarization Diversityorthogonal polarization diversity. horizontal polarization and vertical polarization.

Frequency DiversityThe working principle of this technology is that such fading won’t take place on the frequency outside the coherence bandwidth of the channel.

Diversity ion Technology

Frequency Reuse Pattern

“4 3” reuse mode: one group includes 3 sectors /site ,12 frequency which are

distributed to 4 sites. Every site owns 3 frequency.

A3

D2B1

C3

B2D1

D3

A2C1

B3

C2A1

B3

C2A1

A3

A1B1

D1

D3D2

C3

B2A1

C3D2

C3

C1

D2B1C2A1

A2C1

D3

Frequency Reuse Pattern

A3

C2B1

B3

A2C1

C3

B2A1

A3

C2B1

B3

A2C1

B3

A1C1

A1

A3A2

C3

B2A1

A3A3

C3

C1

B2A1B2A1

A2C1

B3

“3 3” reuse mode: one group includes 3 sectors /site ,9 frequency which are

distributed to 3 sites. Every site owns 3 frequency.

GSM EQUIPMENT

ZXG10 BSS

GSN MSC

BSCSCM

RMM#1

RMM#2

... ...

OMC

BTS 1 BTS n BTS 1 BTS n... ...

...

Gb ATCP/IPX.25DDN

Abis

RMM#4

SCM: System control Module

RMM: Radio Resource Management Module

Each Module of BSC can manage 128 Cells/256 TRXs, and each BSC consists of 4 modules maximally, so one BSC can manage 1024 TRXs maximally.

Structure of ZXG10-BSCStructure of ZXG10-BSC

Advantage:

1 ） Support small capacity network

2 ） Large capacity network can be constructed in phases

Ntrx < 240 1 rack ， 1 SCM+ 1 RMM

240 < Ntrx < 480 2 racks ， 1 SCM + 2 RMM



Capacity Configuration of ZXG10-BSCCapacity Configuration of ZXG10-BSC

Rack Structure

BBIU

BCTL-SCU

BNET

BATC

BCTL-RMU

BATC

BCTL

BNET

BATC

BBIU

BSMU

PCU

1 3 54 6 87 9 1110 12 1413 15 1716 18 2019 21 2322 24 26252 27

POWB

MP

MP

SMEM

COMM

COMM

COMM

COMM

COMM

COMM

COMM

COMM

COMM

COMM

COMM

COMM

PEPD

MON

POWB

MMOOOptionalMMandatoryRemark

12116~1221Qty.

BCTLPOWBMONPEPDCOMMMPSMEM

BBIU

BCTL-SCUBNETBATC

BCTL-RMU

BATC

N_COMM_MPMP=2

N_COMM_MTP=2

N_COMM_MPPP=2 or 4 or 6 or 8

So: N_COMM=6 or 8 or 10 or 12

BCTL Layer

BNET Layer

POWB

CKI

BOSN

DSNI

DSNI

DSNI

DSNI

DSNI

DSNI

DSNI

DSNI

DSNI

DSNI

POWB

SYCK

SYCK

BOSN

1 3 54 6 87 9 1110 12 1413 15 1716 18 2019 21 2322 24 26252 27

BOSN SYCK DSNI CKI POWB BNET

Qty. 2 2 6\8\10 1 2 1

Remark Mandatory M Optional O M M

BBIU

BCTL-SCU

BNET

BATC

BCTL-RMU

BATC

N_DSNI_MP=2

N_DSNI_PP_A=2 or 4

N_DSNI_PP_Abis=2 or 4

SO: N_DSNI=6 or 8 or 10

BBIU Layer

POWB

BIPP

BIPP

COMI

COMI

BIPP

BIPP

TIC

TIC

TIC

TIC

POWB

TIC

1 3 54 6 87 9 1110 12 1413 15 1716 18 2019 21 2322 24 26252 27

TIC

TIC

TIC

TIC

TIC

TIC

TIC

BBIU

BCTL-SCU

BNET

BATC

BCTL-RMU

BATC

COMI BIPP TIC POWB BBIU

Qty. 2 2 or 4 1~12 2 1

Remark Mandatory Optional Optional M M

N_TIC_Abis=N_Abis_E1/4

N_BIPP=N_TIC_Abis/6

BATC Layer

POWB

DRT

AIPP

AIPP

TIC

TIC

TIC

TIC

TIC

TIC

POWB

TCPP

1 3 54 6 87 9 1110 12 1413 15 1716 18 2019 21 2322 24 26252 27

DRT

DRT

DRT

DRT

DRT

TIC

TIC

TCPP

DRT

DRT

BBIU

BCTL-SCU

BNET

BATC

BCTL-RMU

BATC

TCPP DRT AIPP TIC POWB BATC

Qty. 2 1~8 2 1~8 2 1

Remark Mandatory Optional M O M M

N_TIC_A=N_A_E1/4

N_DRT_A=N_TIC_A

1 RACK256TRX

2 RACKS512TRX

3 RACKS1024TRX

Easy to Expand

ZTE BTS Series

BTSV(1) BTSV(2) BS21 MB EMB SBTS BS30

S222 S444 S888

S444 S888 S12/12/12

ZXG10-BTS Rack

• Receiver sensitivity: -110dBm

• Power output: 40/80W

• BTS power control

6 levels static （ step: 2dB ）

15 levels dynamic （ step: 2dB ）

• Rack demension: 1600×600×550 mm3 (H x W x D)

• Max power consumption: 2200W （ 12 TRXs ）

• DC voltage input: -40~-57VDC ； 19~29VDC

• Working temperature: -5oC ~ +45oC

• Relative humidity: 15% ~ 85%

Indoor BTS with 12 TRXIndoor BTS with 12 TRX(ZXG10-(ZXG10-BTSV2)BTSV2)

ZTE中兴 ZXG10-B2

-48V GND

PDM

CCM

RS

T

TRM

TX

RX

RXDRST

CCM

RS

T

RX1

CDU

TEST

ANT

TX1

TX2

RX2

RX3

RX4

EX1

EX2

TRM

TX

RX

RXDRST

TRM

TX

RX

RXDRST

TRM

TX

RX

RXDRST

RX1

CEUTX1

TX2

RX2

RX3

RX4

EX1

EX2

OTX1

TX3

TX4

OTX2

RX1

CDU

TEST

ANT

TX1

TX2

RX2

RX3

RX4

EX1

EX2

RX1

CEUTX1

TX2

RX2

RX3

RX4

EX1

EX2

OTX1

TX3

TX4

OTX2

TRM

TX

RX

RXDRST

TRM

TX

RX

RXDRST

TRM

TX

RX

RXDRST

TRM

TX

RX

RXDRST

RX1

CDU

TEST

ANT

TX1

TX2

RX2

RX3

RX4

EX1

EX2

TRM

TX

RX

RXDRST

TRM

TX

RX

RXDRST

TRM

TX

RX

RXDRST

TRM

TX

RX

RXDRST

RX1

CDU

TEST

ANT

TX1

TX2

RX2

RX3

RX4

EX1

EX2

PDM CMM

AEMTRM

FCM

160

0m

m

600mm

550mm

Physical structure of ZXG10-Physical structure of ZXG10-BTS(V2)BTS(V2)

Architecture of ZXG10-BTS(V2)

Internal bus(control signaling,date flow,clock signal,etc

CMM

PDM

TRM1

AEM

FAN

MMI

ZXG10-BTS （ V2 ）

TRM2

TRM12

BSC

CDUCDUTX1 TX2 RX1 RX2 RX3 RX4 ERX1 ERX2

CDUCDUTX1 TX2 RX1 RX2 RX3 RX4 ERX1 ERX2

TRM1TRM1

TX RX1 RX2

TRM2TRM2

TX RX1 RX2

TRM3TRM3

TX RX1 RX2

TRM4TRM4

TX RX1 RX2

S444S444TRX Configuration

CMMCMM((Controller & Controller & Maintenance Maintenance ModuleModule))

TRMTRM((Transceiver Transceiver Module Module ))

CMM and TRM

CDU(Combiner Distribution Unit ):one duplexerone combiner(2 to 1)one spliter(1 to 4 with 2 extended outputs )

CDUCDU

VSWR_meter

ANT

RTEforward reverse

Alarms

optional

DuplexerCable

Cable

Rx_in

Tx_out

RX1

RX2

RX3

RX4

EX1

EX2

LNA_Splitter

Alarms

TX1

TX250ohm

Hybird_combiner

Each E1(2M) on Abis interface can support 15 TRX, So it can

effectively save the transmission cost.

7.2*16k TCH timeslot / TRX = 1.8*64k TCH timeslot / TRX

1*16k signaling timeslot / TRX

Since very 4 16k timeslot can be multiplexed to a 64k timeslot,

each E1 consists of 32 64k timeslot

( n + 1 ) / 4 + n * 1.8 + 1 = 32 n = 15

Multiplex ratio on Abis interface is 15:1Multiplex ratio on Abis interface is 15:1

OMC-R

The adoption of OMC aims at the local or centralized operation and management. So network mode of OMC-R includes two: local networking and centralized networking. They will be introduced in detail later.

OMC enables NSS/BSS to connect with upper-level mobile network management center through Q3 interface or DB interface.

BTS is managed and maintained by BSC. The local BSC communicates with the server over LAN, and the remote BSC accesses the OMC-R server through centralized networking. The network topology of OMC-R is given in this Fig.

One OMC-R can manage 10 MSC, 16 BSC, 4096 BTS

Upper-level NMC

TCP/IP

TCP/IP

TCP/IP

Billing Center

PCM/X.25/DDN...ZXG10-BSC

ZXG10-BSC

ZXG10-MSSClient

Client

Client

Client

Q3 DB

OMC

LAN/WAN...

Server

Router

Router

Hub

Hub

Hub

OMC-R Structure

Local Maintenance Terminal

OMC-R Sever

BSC 1

Client terminal

Router/FE

LAN

PCM

LMT (I)

LMT (II)

MSC

LAN/RS-232

Thank You

GSM PPT

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Transcript of GSM PPT