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Copyright
Copyright of this manual belongs to LG Electronics.
This manual may be reproduced, distributed or in any form without the express written
permission of LG Electronics.
Registered Trademark
LG, is the registered trademark of LG. In addition, all the registered trademarks
mentioned in this document is the registered trademarks of LG Electronics.
The information contained in this manual reflects the information available at
the point of publication date as precisely and completely as possible. The
results of using the information not mentioned in this manual or the risk of
misunderstanding this document remain with the user.
The information in this manual is subject to change due to functionenhancement, change of design, etc. If you want the modified manual or have
any question on this manual, please contact:
Address :
Tel :
If you have any complaint about the product or related question, please
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2002 LG Electronics, Inc. All rights reserved
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Subsystem Description
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PREFACE
Document descriptionThis document describes functions, features, structure, specifications, etc of STAREX-
IS BTS, which is the BSC on the CDMA network.
Target audienceThis document is written for system operators and skilled technical manpower who is
eager to get familiar with this system.
SummaryThe contents of this document are as follows:
Chapter 1. BTS Overview
This chapter deals with the following to provide general information on
BTS.
LG CDMA network Configuration
BTS features, specifications, system configuration, interface, and
reliability
Chapter 2. BTS Configuration
This chapter covers the following to give the reader insight to the BTS
configuration:
BSC H/W configuration
BSC S/W configuration
Chapter 3. BTS Functions
This chapter describes the following major functions that BTS provides:
Call processing, location registration processing, hand-off, power
control, and paging control GPS receiving function, diversity, and high-speed packet data service
Supplementary functions
Chapter 4. BTS Operation and Maintenance
This chapter deals with the following concerning BTS operation and
maintenance functions:
System initialization function
Configuration management, user interface function, statistics function,
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NMS interface function, and Remote Control
Status management, fault management, test and diagnosis function, and
security function
Inventory function and overload control function
MarksThe marks below art used in this document. Though the information provided along
with the mark may not relate to the contents of this document, a user should keep this in
mind in order to use the system safely and correctly.
Reference It provides additional information for related contents
Note Not following this Note may damage the system
Warning Not following this Caution may cause critical system failure and
damage the operator physically
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Subsystem Description
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Contents
Chapter 1. BTS Overview ....................................................... 6
1. Introduction ..................................................................................................................... 6
2. Configuration of Mobile Communication Network ................................................................ 7
2.1 Circuit Core Network(CCN) ............ ............. ............. ............. ............. ............. ............. ........ ..... . 7
2.2 Radio Access Network(RAN) ............ ............. ............. ............ ............. ............. ............. ........... 9
2.3 Packet Core Network(PCN) ............. ............. ............. ............. ............ ............. ............. ........ ..... . 10
3. Features ......................................................................................................................... 11
4. Specifications .................................................................................................................. 13
5. System Configuration ....................................................................................................... 17
Chapter 2. BTS Configuration ............................................. 18
1. Overview ......................................................................................................................... 18
2. H/W Configuration ........................................................................................................... 19
2.1 DBPB (Digital Bank Processor Block) ............. ............. ............. ............ ............ ..... ..... ..... ..... ... 19
2.2 BANB (BTS ATM Network Block) ........... ............. ............. ............. ............. ............. ......... ..... . 21
2.3 RCCB (Radio & Channel Control Block) ............ ............ ............. ............. ............. ....... ..... ..... .. 23
2.4 BSPB (Base Station Signaling Processor Block) ............ ............. ............. ............. ..... ..... ..... ..... .. 25
2.5 CFEB (Compact Front End Block) ............. ............. ............. ............. ............. ............. ........ ..... 28
2.6 LPAB (Linear Power Amplifier Block) ............ ............. ............. ............. ............ ..... ..... ..... ..... ... 31
2.7 BTGB (BTS Timing Generation Block) ............ ............. ............. ............. ............ ..... ..... ..... ..... ... 32
2.8 RISB (RF & IF Supervisor Block) ............. ............. ............ ............. ............. ............. ...... ..... ..... ..34
2.9 BSTB (Base Station Test Block) ............. ............. ............. ............. ............ ............. ...... ..... ..... .. 36
2.10 BOTB (BeacOn Transmitter Block) ............. ............. ............ ............. ............. ............. ........ ..... . 38
3. Software Configuration .................................................................................................... 41
3.1 Software Design Concept ............. ............. ............. ............. ............. ............. ............. ..... ..... ..... .. 41
3.2 S/W Architecture ............ ............. ............. ............. ............. ............. ............. ............. ..... ..... ..... ... 42
3.3 Major functional configuration ............. ............. ............. ............. ............. ............. ............. ......... 43
Chapter 3. BTS Functions .................................................... 481. Call Processing .................................................................................................................. 48
1.1 Voice Call Processing ............ ............. ............. ............. ............. ............. ............. ............. .......... 48
1.2 Data Call Processing ................................................................................................................. 49
1.3 Call Admission Control ............ ............. ............. ............ ............. ............. ............. ...... ..... ..... ... 50
1.4 Channel Processing .....................................................................................................................53
2. Location Registration Processing ......................................................................................... 56
2.1 Location Registration by MS ............. ............. ............. ............ ............. ............. ............. .......... 56
2.2 Location Registration by MSC ............ ............. ............. ............ ............. ............. ............. ........... 57
3. Hand-off ......................................................................................................................... 58
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3.1 Types of hand-off ............ ............. ............ ............. ............. ............. ............. ............. ..... ..... ..... ....58
3.2 Voice Call Hand-off ............. ............. ............. ............. ............. ............ ............. ............. ....... ..... .. 60
3.3 Data Call Hand-off ............. ............. ............. ............. ............. ............. ............. ............. ...... ..... .. 62
4. Power Control .................................................................................................................. 63
4.1 Overview ............ ............. ............. ............ ............. ............. ............. ............. ............. ....... ..... ... 63
4.2 IS-95A/B based Power Control ........... ............. ............. ............. ............. ............. ............. ........... 65
4.3 IS-2000 based Fast Power Control ............ ............. ............. ............. ............. ............. ...... ..... ..... ..67
4.4 Performance of Power Control ............ ............. ............. ............ ............. ............. ............. ........... 68
5. Paging Control .............................................................................................................. 69
5.1 Overview ............ ............. ............. ............ ............. ............. ............. ............. ............. ....... ..... ... 69
5.2 Quick Paging ............ ............. ............. ............. ............. ............. ............. ............. ............ .......... . 69
6. GPS Receiving Function .................................................................................................... 70
7. Diversity ......................................................................................................................... 717.1 Overview ............ ............. ............. ............ ............. ............. ............. ............. ............. ....... ..... ... 71
7.2 Type of Diversity ............ ............. ............. ............. ............ ............. ............. ............. ..... ..... ..... .... 72
8. High Speed Packet Data Service ......................................................................................... 72
8.1 Overview ............ ............. ............. ............ ............. ............. ............. ............. ............. ....... ..... ... 72
8.2 Channel Assignment Control ............ ............. ............ ............. ............. ............. ............. ........... 73
9. Supplementary Function .................................................................................................... 73
9.1 QOF (Quasi-Orthogonal Function) ............. ............. ............. ............. ............. ............. ........ ..... 74
9.2 Flexible Paging ............ ............. ............. ............. ............. ............. ............. ............. ..... ..... ..... ... 74
9.3 PACA (Priority Access & Channel Assignment) ............ ............. ............. ............. ..... ..... ..... ..... .. 74
9.4 Tiered Service ............. ............ ............. ............. ............. ............. ............. ............. ............. ......... . 76
9.5 NDSS (Network Directed System Selection) ............ ............. ............. ............. ............. ......... ..... 77
Chapter 4. Operation and Maintenance of BTS ................. 79
1. Operation Function ........................................................................................................... 79
1.1 System Initialization Function ........... ............. ............. ............. ............. ............. ............. ........... 79
1.2 Configuration Management ............ ............. ............. ............. ............. ............. ............. ........ ..... . 80
1.3 Man-machine interface Function ............. ............ ............. ............. ............. ............. ...... ..... ..... .. 81
1.4 Statistics Function ............. ............. ............. ............. ............ ............. ............. ............. ....... ..... .. 82
1.5 Interface with NMS ................................................................................................................. 83
1.6 Remote Control ............. ............. ............. ............. ............. ............. ............. ............ ..... ..... ..... ... 832. Maintenance Function ....................................................................................................... 84
2.1 Status Management..................................................................................................................... 84
2.2 Fault Management ........... ............. ............. ............. ............. ............. ............. ............. ........ ..... .. 84
2.3 Test and Diagnosis Function ........... ............. ............. ............. ............. ............. ............. ........ ..... .. 86
2.4 Security Function ............. ............. ............ ............. ............. ............. ............. ............. ....... ..... .. 88
2.5 Inventory Function ............. ............. ............. ............. ............. ............. ............ ............. ....... ..... .. 89
2.6 Overload Control Function ............ ............. ............. ............. ............ ............. ............. ........ ..... .. 89
Abbreviations ........................................................................... 91
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Chapter 1. BTS Overview
1. Introduction
Located between MS(Mobile Station) and BSC(Base Station Controller) in a personal
communication system, STAREX-IS that uses CDMA digital mobile communication
technology, BTS controls calls for the MS and performs system operation and maintenance.
More specifically, it induces the MS to recognize BTS for the first time, provides the
necessary information, allocates traffic channels for the call request made by the MS, and
opens a call path.
In addition, it provides new functions such as high-speed data service, multimedia service,
new hand-off, etc which are defined in the IS-2000 standard.
STAREX-IS BTS, CDMA2000 system developed by LGE, is based on ATM; therefore, it is
most suitable for the network structure defined in IOS v4.0 and IS-2000 standard.
Since BTS is based on ATM, it makes evolution easy when migrating to 3X and has the
network structure that can provide high-speed data service that advances fast
technologically.
Interface between BSC and BTS can be made by OC-3 of STM-1 rate, as well as the existing
E1/T1 method; therefore, BTS can process various control signals and traffic signals sentand received between BTS and BSC fast and in more stable manner, providing the more
reliable services.
STAREX-IS Standard BTS is installed outdoors and depending on the features of the
installation area, it can select from 1FA/3Sector to 8FA/3Sector.
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2. Configuration of Mobile Communication NetworkWith the addition of PCN(Packet Core Network), the CDMA2000 mobile communication
network is divided into three parts to support RAN(Radio Access Network), CCN(Circuit
Core Network) and Packet Data Service.
Fig. 0-1 CDMA2000 Mobile Communication Network Configuration Diagram
1.2-1(1):
MSC/VLR(SSP)MSC/VLR(SSP)
BSC(#0)
BSC(#0)
BSC(#11)
BSC(#11)
BTS#0
BTS#0
MSMS
MSMS
PSTNPSTN
/PLMN/PLMN
/ISDN/ISDN
BTS#47
BTS#47
BTS#0
BTS#0
BTS#47
BTS#47
HLRHLR
IntraIntra
IPIPPDSNPDSN
HAHAAAAAAA
SMSCSMSCVMS
/FMS
VMS
/FMS
AuCAuC
IWFIWF
InternetInternet
G/WRouter
G/W
Router
SCESCE
SCPSCP
IPIP SMSSMS
RAN CCN
PCN
2.1 Circuit Core Network(CCN)
CCN(Circuit Core Network) is used to provide the existing voice service and to interface
with existing networks such as PSTN, PLMN, ISDN, etc.
In addition, it is configured with network elements to provide the supplementary services as
well as network services for mobile subscribers.
Mobile Switching System(MSC)
As a center of the mobile communication network, MSC(Mobile Switching Center) provides
interface between a mobile communication network and a fixed network such as PSTN,
ISDN, etc and between a mobile communication network and other carriers networks such
as PLMN, internet network, and PSPDN.
In addition, in order to provide a switching function, MSC exchange data HLR(Home
Location Register) and VLR(Visitor Location Register). It interfaces with BSC to send and
receive signals and voice data with the MS(Mobile Station).
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Visitor Location Register(VLR)
VLR(Visitor Location Register) temporally stores and manages all the information on MS
existing in the areas it manages. And when mobile subscribers set up a call, VLR sends the
information on the corresponding subscriber to MSC at the MSCs request.
HLR-related data are maintained identically with the HLR at all times.
Home Location Register(HLR)
HLR(Home Location Register) is a DB system that stores and manages subscriber
parameters and location information on the MS registered in its areas. HLR managesimportant data such as MS accessing ability, basic service, supplementary service, etc and
routes terminating subscribers.
Furthermore, in case of intelligent network service, HLR provides the wireless intelligent
network for next-generation by providing subscriber-related data to WIN network element.
Authentication Center(AuC)
AuC(Authentication Center) is a system that processes the subscriber authentication and
interfaces with the mobile communication network via MSC and HLR.
Operation and Maintenance Center(OMC)
OMC(Operation and Maintenance Center) performs operation and maintenance on all the
elements that configure the mobile communication network. It interfaces with MSC by
TCP/IP and TMN Q .
Customer Care and Billing System(CSBS)
CCBS(Customer Care and Billing System) collects charging, calculates a charge, and
manages subscribers.
Service Control Point(SCP)
SCP(Service Control Point) provides WIN(Wireless Intelligent Network) service and
provides data requested by SSP(MSC) through the management of the WIN service
subscribers.
Service Switching Point(SSP)
SSP(Service Switching Point) provides the service data requested by subscribers to SCP by
recognizing intelligent service calls and performs routing according to SCP notification.
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Short Message Service Center(SMSC)
As a system that processes the short message service, SMSC(Short Message Service Center)
interfaces with the mobile communication network via MSC and HLR.
Service Management System(SMS)
SMS(Service Management System) performs OA&M in relation to SCP operation, DB
management in SCP, and SCP external interface.
Service Creation Environment(SCE)
As a tool that is used to develop the intelligent service, SCE(Service Creation Environment)
is used when the developer or operator implements the service logic.
Intelligent Peripheral(IP)
IP(Intelligent Peripheral) provides additional intelligent services to the intelligent service
users/subscribers by using voice and character.
Voice Mailing System(VMS)
VMS(Voice Mailing System), a system that processes the voice mailing service, it interfaces
with MSC by PRI and NO.7.
2.2
Radio Access Network(RAN)
RAN(Radio Access Network) is configured with network elements to provide signals and
communication on radio, which is a mobile network service feature, and provides a path to
PCN(Packet Core Network).
Base Station Controller(BSC)
By interfacing with several BTSs, BSC(Base Station Controller) performs the following
functions: inter-cell hand-off processing, call control, BTS operation and maintenance
function, etc.
BSC and MSC interfaces with each other by No.7 link.
Base Station Transceiver System(BTS)
The area to which the BTS power reaches is called cell. By radio communication with the
MS in the BTS cell, it provides the mobile communication service to subscribers.
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For this, BTS sends and receives wireless signals by encoding and decoding wireless
channels. In addition, in order to provide calls with better quality at a reasonable price, it
provides the following functions: the adjustment of transceiving signal strength, upward link
quality measurement, link quality measurement, space diversity, wireless resources
management and self-maintenance.
Packet Control Function(PCF)
As a newly-added element to the CDMA 2000, PCF provides signals and packet data to
PCN on radio.
2.3
Packet Core Network(PCN)
As a network element that provides a packet service by interfacing with the PSPDN and the
Internet network, PCN(Packet Core Network) follows IETF institutions regulations that the
existing Internet network uses for inter-network interface standards Internet.
Packet Data Serving Node (PDSN or FA)
PDSN(Packet Data Serving Node) or FA(Foreign Agent) provides the packet modem
function to interface with the Internet network and provides switching and packet charging-related data for the packet data.
Authentication, Authorization, Accounting (AAA)
AAA provides network accessing authentication, authorization, and accounting functions for
packet calls.
Home Agent(HA)
As a network element that provides Mobile IP to packet subscribers, HA(Home Agent) is
added to secure the mobility of the packet subscribers that each FA(Foreign Agent) has.
Gateway Router
Gateway Router provides a Gateway function between each carriers mobile communication
packet network and the external packet and Internet network.
It is required to construct the general LAN network. When providing F/W(Fire Wall) that
provides a security function, it provides a Gateway function as a single path.
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3. Features
UP-to-date and Various Function Support
STAREX-IS BTS provides the following functions along with basic a call processing
function:
High-speed Data Service and Multimedia Service
STAREX-IS BTS supports the line communication(i.e., fax and modem communication) as
well as packet data communication(i.e., the Internet communication) and can provide both
services at the same time. STAREX-IS BTS can support up to 144Kbps high-speed data
service and multimedia services including video data.
Tired Service Function
STAREX-IS BTS provides Tired Service which provides the differentiated services such as
imposing a different rate or providing special data service to special subscribers in the User
Zone.
OTD(Orthogonal Transmission Diversity) Function
STAREX-IS BTS supports the OTD function that sends transmission signals to the MS
simultaneously by diversifying them into two signals with orthogonal characteristics. The
use of OTD can improve the data quality that the MS receives.
NDSS(Network Directed System Selection) Function
STAREX-IS BTS supports the NDSS function that changes the subscribers location
registration to the corresponding network when the IS-95 A/B network subscriber registered
his or her location on the CDMA2000 network and vice versa.
Quick Paging Function
STAREX-IS BTS supports a Quick Paging function that reduces the power consumption by
activating the paging receiving function of the MS only when the paging data are changed
QOF Function
STAREX-IS BTS supports QOF, the multiple codes with new semi-orthogonal
characteristics by multiplying 256chip Walsh by masking function(QOF sign, Walsh rot) for
transmission speed control and receiving diversity, forward channel addition and allocation,
etc.
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Large Capacity Subscriber Accommodation
STARX-IS Standard BTS can accommodate up to 768 channels(voice channel) in one rack
by using a highly-integrated channel card. When installing another expansion rack, it can
accommodate twice as much as the basic rack capacity.
In addition, it can use channels by selecting the Omni method and sectors with the identical
channel resources and by fooling them between FA and Sector within one shelf . As shown
above, STARAX-IS BTS can allocate channels in various ways and makes the efficient
operation possible with limited resources.
ATM Network Provision
STAREX-IS BTS uses ATM network as the communication path of subscriber voice and
data traffic signal and inter-processor control signal. CDMA2000 system can process vastcapacity subscriber traffic signals through the ATM network and support various types of
multimedia services by QoS(Quality of Service) support.
In addition, with the structure suitable for the high-speed data transmission, the 3G 3X MC
and 1X EV-DO Dual Mode as well as 4G BSS ALL IP network can be also applied to it.
System Modularization Structure
All the H/W in STAREX-IS BTS is modularized; therefore, the system can be easily
expanded or reduced without changing the already-installed system structure by inserting or
removing the corresponding modules. In addition, S/W that is run in BTS processors is
modularized as well. For this reason, when the S/W function is modified or complemented,
it can minimize the service suspension while minimizing the system modification range by
simply modifying the corresponding modules.
Convenient System Operation
The operator can control STAREX-IS BSC, BTS in the station/office through BSM easily.
BSM displays each device status inserted in the system in graphics so that the operator can
check the system status and take an appropriate action. In addition, BSM interfaces with
external systems through Ethernet and Dialup-Modem for debugging and maintenance
management functions.Other BTSs provide the following functions for convenient and operation of the system:
statistics, configuration, status, fault diagnosis, and test function.
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4. Specifications
Capacity
The following shows STAREX-IS BTS capacity:
Division Specifications
Max. Carriers (without TD) 8FA/3Sector, 6FA/6Sector
Max. Carriers (With TD) 6FA/3Sector
Max. Trunk 48 E1/T1
Number of CE per Channel Card 64CE/CC
Number of Channel Card 6EA/shelf(Max. 384CE), 12EA/Rack
Type of Amplifier LPA(60 Watts/Module),
HPA(30 Watts/Module)Number of LPA 6EA/Shelf(360 Watts)
RF Power at Front End Ant Port 16 Watts/FA
Cooling FAN
E1channel counts between
BSC and BTS
8K EVRC/QCELP Based Maximum 156 voice calls/E1, 121 voice
calls /T1
13K QCELP Based Maximum 126 voice calls /E1, 97 voice
calls /T1
64K Maximum 13 data calls/E1, 10 data calls/T1
153.6K Maximum 6 data calls/E1, 4 data calls/T1
Transceiver Specifications
The following shows the STAREX-IS BTS transceiver specifications:
Receiver Specification
Parameter Description Comments
Operation Band 824 ~ 949 MHz
Diversity Dual Diversity on Rx
Frequency Transition Straight Transition of license Block
Operation
RF Interface 50 Nominal Impedance
Noise Figure 5dB (Max)Sensitivity FER is 1.0% or less with 95% Confidence -117dBm per RF Input Port
Dynamic Range FER is 1.0% or less with 95% Confidence Not less than65dBm /1.23 MHz
in AWGN and Eb/No of 10 dB
1dB
Conducted Spurious
Emissions
Less than 80dBm in 30KHz RBW,
RX Band.
Less than 60dBm in 30KHz RBW,
TX Band.
Less than 47dBm in 30KHz RBW,
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All Other Frequencies
Transmitter Specification
Parameter Description comments
Operation Band 869 ~ 894 MHz
Diversity Option of Diversity on TX
Frequency Transition Straight Transition of License Block Operation
Frequency Tolerance Within 5 x 10-8 of the FA ( 0.05ppm)
Pilot TimeTolerance
10 s
Pilot Channel to Code Channel
Time Tolerance
The time error between the Pilot Channel and all
code channels comprising the Forward CDMA is
within 50ns
Pilot Channel to Code Channel
Phase Tolerance
The phase differences between the Pilot Channel
and all code channels sharing the same Forward
CDMA should not exceed 0.05 radians
Waveform Quality is greater than 0.912 (excess power < 0.4dB)
Total Power within +2dB and -4dB of nominal power
Code Domain Power 27dB or more below the total power in each
inactive channel
When operating with theFundamental
Channel Test Mode 1Conducted Spurious Emission -45dBc 750kHz @30kHz RBW
-60dBc 1.98MHz@30kHz RBW (Pout33dBm)
Power
The following shows the information in relation to STAREX-IS BTS power:
Division Specification
Current Input Voltage(AC) Single-phase 220V, 3-pjase 380V 20%Current Input Frequency 50/60Hz
System Input Voltage(DC) +24 ~ 27V(DC)
Output Voltage(Current Consumed) DC 300A (4FA/3Sector based)
Efficiency More than 85%
Equipment
The table below shows the rack size(WidthDepthHeight) and weight where the STAREX-
IS BTS is mounted. Rack height includes the bottom area of the rack.
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Division Specification
Rack Size 750mm(W)700mm(D)1,886mm(H)
Rack Weight Approximately 220 Kg(Based on 1 Rack)
Environments
The table below describes the following: 1) temperature, humidity, height(altitude), and
vibration conditions in which the STAREX-IS BTS can operate normally and (2) noise, dust,
and the strength of the electromagnetic interference generated when STAREX-IS BTS
operates.
Regarding temperature and humidity, Operation Temperature is a optimal temperature
condition that is needed for STAREX-IS BTS to operate normally and Operation
Condition is not the optimal condition, but the condition that the STAREX-IS BTS cannormally operate.
Among the items below, Earthquake/Vibration and EMI(Electro-Magnetic Interference)
satisfied test conditions suggested by FCC, UL, Telcordia, internationally approved
institutions.
Division Range ApplicableStandards
Operation Temperature 0 ~ 50 GR-63-CORE
Storage Temperature -40 ~ 70
Humidity 5 ~ 95% (Moisture in the air should not exceed 0.024Kg) GR-63-CORE
Height(Altitude) -60 ~ 4000 m
Earthquake/Vibration Standards satisfied GR-63-CORE
Noise In 1.2m distance, noise of less than 65dBA level occurred
Dust 0 ~ 20 ug/m3 GR-63-CORE
EMI Standards satisfied GR-1089-CORE
Inter-system Interface
STAREX-IS BTS interfaces with MS, and BSC as follows:
Division Digital Interface Signal Interface Interface Protocol
BTS BSC E1/T1 ATM(AAL2/AAL5) LGE Proprietary
BTS MS Air Interface IS-2000
Minimum Capacity Standard for BTS
BTS is designed to meet the minimum capacity standards of other BTSs requested by IS-
97D such as frequency accuracy(0.05ppm), receiving sensitivity(-117dBm), wave
quality(0.912), etc.
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Interface between BTS and BSC
Interface between BSC and BTS uses LGE Proprietary standard. BSC and BTS send 8K or
13K voice data and packet data, line data, and various control signals by E1/T1 link. Signal
interface uses ATM(AAL2/AAL5).
Interface between BTS and MS
BTS and MS meet the IS-2000 standards which are radio standards for CDMA2000. The
channels defined in IS-2000 are divided into Logical Channel on the Signaling Control side
and Physical Channel on CAI. The transmission speed differs depending on channels and in
case of a traffic channel, it can transmit the user data at maximum144Kbps.
Reliability
The main part of STAREX-IS BTS H/W is duplicated for the system reliability and ismodularized for easy operation and maintenance.
With the logical and physical function distribution structure, S/W is suitable for the
distribution-type system and is Fault-Tolerant structure. It guarantees the maximum
transparency.
The system reliability can be represented through MTBF(Mean Time Between Failure) and
the availability can be represented through MTTR.
STAREX-IS BTS FR and MTBF are as follows:
MTBF MTTR
More than 30 years Less than 4 hours
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5. System Configuration
STAREX-IS BSC is composed of the following racks in general:
ISBR (IS Standard Base station Rack)
Fig. 0-2 STAREX-IS BTS Basic Configuration Diagram (8FA/3Sector)
One ISBR00, as a basic rack of STAREX-IS BTS, can accommodate up 4FA/3Sector. On theupper part of the rack, FR block and LPA block are mounted and below them, channel
processing block, BTS control block, and blocks for other supplementary blocks are
mounted.
ISBR01, as an additional rack of STAREX-IS BTS, is installed to increase the BTS service
capacity. On this rack, only RF block, channel processing block, and digital processing block
are mounted additionally as a result of the increase of the rack capacity.
Blocks mounted on STAREX-IS BTS racks are as follows:
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Rack Name Block Mounted
ISBR00 CFEB, LPAB, DBPB, RCCB, BSPB, BANB, BSTB, RISB, BOTB, BTGB
ISBR01 LPAB, DBPB, RCCB
Chapter 2. BTS Configuration
1. Overview
For the improvement of the system service stability and reliability, in STAREX-IS BTS,
control system has a distributed control structure, operation system has a serial processing
structure, and the subscriber data have real-time DBMS. In order to maintain the systemperformance even in the worst reference load requested, the main devices (control system,
ATM, data processing system, etc) are duplicated in Active/Standby mode. In addition, H/W
is modularized by the function so that the subscribers can be easily increased and the
functions are easily added or changed without affecting the service even during the system
operation.
In light of the functions, STAREX-IS BTS H/W is configured with the following blocks:
Fig. 0-3 STAREX-IS BTS Configuration Diagram
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2. H/W Configuration
2.1 DBPB (Digital Bank Processor Block)
2.1.1 Functions
As a block that processes CDMA channels in BTS, DBPB (Digital Bank Processor Block)performs digital and analogue signaling process for each channels call processing as well as
for interface with RF block.
Major Functions
CDMA Digital Baseband processing (Overhead channel + Traffic channel)
Forward link Base-band Digital Combining, and backward link parity check
and generation
Digital shelf Timing, reference frequency distribution, and RF device
control
Capacity
Based on voice services, it supports 64 CH/DBPA (based on 8K)
2 CSM5000 chips by QualComm are inserted in one DBPA
Interface
DBPA interfaces with RCCA through ATM Cell and exchanges actual traffic with RCCB
BUDA RCCA. RCCA interfaces with DBPA and BSPB UCPA through ATM Cell and
interfaces with BANB at STM-1. DBPA also interfaces with LPAB, BUDA and PACA in
serial, controlling each device.
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Fig. 0-4 Interface between DBPB and Other Blocks
2.1.2 Configuration
The DBPB is configured as follows:
Fig. 0-5 DBPB Mounting Diagram
The function of each board of DBPB is as follows:
Board Name Quantity Functions
DBPA 6 boards /shelf -Assignment of overhead channel and traffic channel
-Acceptable if the quantity is 6 boards per 2FA/3Sector
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RCCA 2 boards /shelf - Base-band digital combining (Forward link)
- Parity check and generation (Backward link)
- Distribution of timing and reference frequency of digital shelf
- RF Device Control
2.2 BANB (BTS ATM Network Block)
2.2.1 Functions
BANB (BTS ATM Network Block) performs the ATM Network function to switch all
traffics occurred in BSS and Control ATM Cells.
Major functions
ATM Cell Routing function within BTS
Provides the transmission line of ATM Packet between BTS and BSC
(E1/T1)
Provides Packet Routing function with BTS Peripherals
Provides Remote Control function for PSTN Network
Capacity
Provides 16 E1/T1 for each LICA board (max. 48 E1/T1 available with 3
boards mounted)
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Interface
Each cell node of BCRA of BANB is the STM-1 grade, which is assigned to RCCA, LICA
and UCPA. It also interfaces with BPPA via HDLC bus.
LICA interfaces with BCRA via STM-1, and it also interfaces with ALPA of BSC via E1/T1.
BPPA interfaces with each board of BANB via HDLC bus, and it also interfaces with each
peripheral within BTS via RS-422.
Fig. 0-6 Interface between BANB and other blocks
2.2.2 Configuration
The BANB is configured as follows:
Fig. 0-7 BANB Mounting Diagram
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The function of each board of BANB is as follows:
Board Name Quantity Functions
BCRA 2 -ATM Cell Routing in BTS
- Duplication of Active/Standby (Warm Standby)
LICA 1 -Provides E1/T1 Trunk Interface between BTS and BSC
-Max. 3 boards mountable with load sharing
BPPA 1 -Performs the function of Packet Routing for supplementary equipment suchas LPA, BADA, DRAN, RISA, Beacon within BTS
RCMD 1 -Daughter board attached to Back board
-Provides Remote Control function for PSTN network
APPD 1 -Daughter board attached to LICA
-AAL2AAL5 Convertible
2.3 RCCB (Radio & Channel Control Block)
2.3.1 Functions
RCCB (Radio & Channel Control Block) converts Baseband signal and RF signal Up/Down
to transmit them to the related block, and it also measures and calibrates RF power.
Major functions
Converts digital signal transmitted from Channel Card to analog signal and
converts the signal to IF and RF signal upward to be transmitted to LPA
Converts the signal inputted from LNA to the lower frequency and converts
the signal to digital signal through A/D converter
Measures the final transmission RF power for each FA and sector of BTS
and report the result to upper level.
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Capacity
Provides 1 Tx IF Out Port for each BUDA 1EA
Provides 2 Rx IF Input Ports for each BUDA 1EA
Max. 2FA/3Sector acceptable for each PACA 1EA
Interface
BUDA of RCCB transmits digital data to DBPA of DBPB through back plane, and it also
performs Serial Bus Communication with RCCA using Address, Control and Data Signal.
PACA measures the strength of transmission signal measured at Front End and transmitsControl Signal to the higher level of RCCA.
Fig. 0-8 Interface between RCCB and other blocks
2.3.2 Configuration
The RCCB is configured as follows:
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Fig. 0-9 RCCB Mounting Diagram
The function of each board of RCCB is as follows:
Board Name Quantity Functions
BUDA 6 -Same quantity as DBPA, pairing with DBPA
-Up converting of baseband signal
-Down converting of RF signal
-RF signal output adjustable with Gain Control
PACA 1 -1 board mountable with 2FA/3Sector accepted for each board
-Measures RF transmission power for each FA and Sector
-Performs supplementary transmission power control
2.4 BSPB (Base Station Signaling Processor Block)
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2.4.1 Functions
BSPB(Base Station Signaling Processor Block) is the Control Section of BTS to perform the
functions of BTS such as initialization, call processing, wired/wireless resource
allocation/de-allocation and wire/wireless link management.
Major functions
General control and status management of BTS
General collection of H/W Alarm of BTS
Provides the timing required for BTS
Provides H/W Remote Control for Peripheral Devices of BTS
Capacity
UCPA Core Processor : MPC750(722MIPS, 400MHz), L2 Cache supported
UCPA I/O Processor : MPC8260(280MIPS, 200MHz),, 16M Local Memory
acceptable
Interface
BSPB provides various interfaces such as ATM, Fast Ethernet, HDLC, UART, etc. in order
to control each board of BTS. By these procedures, BSPB transmits and receives Control
and Alarm Signal.
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Fig. 0-10 Interface between BSPB and other blocks
2.4.2 Configuration
The BSPB is configured as follows:
Fig. 0-11 BSPB Mounting Diagram
The function of each board of BSPB is as follows:
Board Name Quantity Functions
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UCPA-E
(BSP)
2 - Duplication of Active/Standby
- Initialization of BTS
- General Control and Status Management of BTS
- Collection of H/W Alarm of BTS
- Provides Timing required for BTS
- Provides call processing function
- Allocation/De-allocation of wire and wireless resources
- Wire/wireless link management
ARIA 1 - Collection and management of alarm of LPA, FAN, LNA,
RCCA, BADA, RISA, BOTA, GPS-S, RISA
- H/W Remote Control of boards as above
2.5 CFEB (Compact Front End Block)
2.5.1 Functions
CFEB (Compact Front End Block) is the block to process RF transmitting/receiving function
and to perform the related functions such as high power amplification of transmitted signal,
low noise amplification of received signal, conversion of transmitted/received frequency,
transmitting/receiving diversity.
Major functions
Low noise amplification of received signal
Filtering of transmitted/received signal
Provides received signal to the receiving terminal of BUDA (based on each
FA)
Capacity
Consists of 2 units such as A path and B path for each sector (Receiving
Diversity)
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Each unit consists of Duplexer, LNA, directional coupler and distributor as
transmitting/receiving filter
Interface
CFEB interfaces with Antenna via Tx/Rx Cable. It also interfaces to LPA via Forward
Traffic and interfaces to RCCB via Reverse Traffic and LNA.
Fig. 0-12 Interface between CFEB and other blocks
2.5.2 Configuration
The CFEB is configured as follows:
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Fig. 0-13 CFEB Mounting Diagram
The function of each board of CFEB is as follows:
Board Name Quantity Function
Duplexer
(Tx/Rx Filter)
2 boards /Sector -Performs the function to filter transmitted/received signal.
-Comprises transmitting/receiving band-pass filter with
Duplexer structure in order to decrease the number of antenna
used for each sector.
LNA
(Low Noise Amplifier)
2 boards /Sector -Performs Low Noise Amplification of filtered receiving signal.
-The input terminal of LNA is connected to the output terminal
of Duplexer receiving filter.
-The output terminal of LNA is connected to Divider to
transfer the receiving signal to BUDA
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2.6 LPAB (Linear Power Amplifier Block)
2.6.1 Functions
After receiving the transmitting signal which was up-converted from BUDA, LPAB
amplifies the signal with high power to be transferred to front end.
Major functions
High power amplification of transmitted signal
Capacity
Compliant to IS-97D Performance Standard
60 Watts/Module
16 Watts/FA
Interface
LPAB receives the signal up-converted from BUDA of RCCB via Active Divider. It also
transfers the signal amplified from LPA via Combiner to Front End.
Fig. 0-14 Interface between LPAB and other blocks
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2.6.2 Configuration
The LPAB is configured as follows:
Fig. 0-15 LPAB Mounting Diagram
The function of each board of LPAB is as follows:
Board Name Quantity Function
LPA 6 boards /shelf
(Based on 4FA/3Sector)
-High power amplification of transmitted signal
2.7 BTGB (BTS Timing Generation Block)
2.7.1 Functions
BTGB receives visual information from GPS Satellite to provide visual and location
information.
Major functions
Provides the internal BTS with TOD (Time of Day), 10MHz and 1PPS
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Interface
GPS interfaces with UCPA of BSPB and RS-232C to transfer each visual information via
UCPA to the internal BTS. It is also connected with GPS antenna via TNC Cable.
In addition, GPS provides each device of internal BTS with TOD, 10Mhz and 1PPS GPS via
each terminal of rear panel of GPS.
Fig. 0-16 Interface between BTGB and other blocks
2.7.2 Configuration
The BTGB is configured as follows:
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Fig. 0-17 BTGB Mounting Diagram
The function of each board of BTGB is as follows:
Board Name Quantity Function
GPS-R 1 -Divided into two main frames, GPS-R and GPSM
-GPSM receives the information on L1 Band such as signal & orbit
information and mobile visual information from GPS satellite.
-GPS-R performs the comparison and control of various signals received
through GPSM Receiver and provides the signal information to System.
2.8 RISB (RF & IF Supervisor Block)
2.8.1 Functions
RISB performs the function to supervise the waveform of RF and IF from BTS.
Major functions
Supervision of BTS transmitting output spectrum
Identification of abnormal signal and Alarm function
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Collection and storage of signal spectrum
Measurement function of total power for each sector
Measurement function of Channel Power for each channel
Capacity
20FA/3Sector acceptable for each board
Interface
RISA supervises IF signal from the output terminal of BUDA via IFMA (IF Multiplexing
board Assembly) as well as RF signal from the output terminal of RF via RFMA (RF
Multiplexing board Assembly).
In addition, RISA performs status management and control by interfacing with upper-level
BPPA, ARIA and HDLC.
Fig. 0-18 Interface between RISB and other blocks
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2.8.2 Configuration
The RISB is configured as follows:
Fig. 0-19 RISB Mounting Diagram
The function of each board mounted on RISB is as follows:
Board Name Quantity Function
RISA 1 - Supervision of BTS transmitting output spectrum
- Identification of abnormal signal and Alarm function
- Collection and storage of signal spectrum
2.9 BSTB (Base Station Test Block)
2.9.1 Functions
BSTB performs the function to check each channel status at the termination of BTS antenna.
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Major functions
Check of the status of sending-end/receiving-end
Measurement of Antenna VSWR for sending/receiving
Functional test of BTS Channel Element
Functional test of voice Loopback/Marcov of Mobile Simulator
Remote Call function
Interface
BADA (BTS Analysis & Diagnostic Assembly) is controlled by Serial Synchronous HDLC
channel connected via cable to BPPA.
Fig. 0-20 Interface between BSTB and other blocks
2.9.2 Configuration
The BSTB is configured as follows:
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Fig. 0-21 BSTB Mounting Diagram
The function of each board of BSTB is as follows:
Board Name Quantity Function
BADA 1 -Measures the strength of BTS transmitted power and the quality of signal, and checks the operational status of BTS
-Module of BTU as supplementary equipment (Optional)
2.10 BOTB (BeacOn Transmitter Block)
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2.10.1 Functions
BOTB is the board to perform Hopping BeacOn, which provides the function to transmit
Pilot Channel to a desired FA at a regular cycle for a certain time.
Major functions
Provides Forward Pilot Channel
Frequency Hopping function (5FA available via one port per sector)
Receives the reference signal
Performs Status Management and Control function
Interface
BOTA (BeacOn Transmitter Assembly) is controlled by Serial Synchronous HDLC channel
connected via cable to BPPA.
Fig. 0-22 Interface between BOTB and other blocks
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2.10.2 Configuration
The BOTB is configured as follows:
Fig. 0-23 BOTB Mounting Diagram
The function of each board of BOTB is as follows:
Board Name Quantity Function
BOTA 1 -Module of Hopping Pilot Beacon as supplementary equipment.
-Performs the function to transmit Pilot Channel to a desired FA at a
regular cycle for a certain time
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3. Software Configuration
3.1 Software Design Concept
Incremental model adopted
Incremental model is the model to implement final target system by partially implementing
system with incrementally additional function and performance after defining the structure
of whole system. The implementation and design of S/W for STAREX-IS BTS are based on
this incremental model.
Technique of software architecture design
Software architecture was designed with two design techniques such as modular design
technique and object-oriented design (OOD) technique.
The concept of modularity is very critical, because software doesnt have any visible entity
but complexity. Specially, for the system requiring high capacity S/W such as STAREX-IS
BTS, the programming with the concept of modularity applied is absolutely needed, in the
point of design and implementation or maintenance.
For the S/W of STAREX-IS BTS, the elements to minimize the interconnectivity between
softwares were separated from one another, thus to implement the modularity in technical,
functional and practical level. In addition, this modularity provides the advantage of
structural development of S/W and facilitates debugging, changing or addition and deletion
of software, resulting in reduced development time and effort.
Software architecture style
Based on state transition structure, the software architecture was designed with reference to
the following structure style:
Structure according to event-based internal call
Hierarchy structure
Distributed processing structure
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3.2 S/W Architecture
The Software of STAREX-IS BTS consists of several subsystems according to each function
within BTS as follows:
Fig. 0-24 S/W architecture of BTS
The S/W subsystem comprising BTS is composed of 4 subsystems such as BCMS, BRMS,
RCCS and DBPS.
Each subsystem exchanges the signal according to its function, while performing two traffic
processes such as Circuit Traffic Processing to MSC and Packet Traffic Processing to PDSN.
As described above, BTS S/W is modularized and hierarchical so that each subsystem
consists of several function blocks in its lower level. In this case, the block can be classified
into two block types such as call processing block and OAM block.
For the detail of each subsystem, see Chapter 3.3.
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3.3 Major functional configuration
Each S/W block within BTS exists in a subsystem BTS. However, it can be divided into two
block types such as call processing block and OAM (Operation And Maintenance) block
according to the function.
The following subsection intends to understand the functional flow of call processing and
OAM by classifying blocks within each subsystem according to call processing and OAM
function.
3.3.1 Call processing S/W
In view of hardware, Call processing in BTS is performed around BSP (Base Station
Processor) and the S/W applied to BSP is BCMS (BTS Call & Management Subsystem).
Accordingly, the call processing S/W supports call processing and hand-off of BTS by
interworking with BSC, around blocks related to call processing of BCMS. It also performs
the operation and status/resource management within BTS.
Each hardware block of BTC performs a series of procedures related to call processing
through relationship between Master Processor and Client Processor.
The following diagram shows that the call processing S/W resides in the processor of each
H/W block.
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Fig. 0-25 Functional block diagram of call processing S/W in BTS
The following is the table which simply shows the function of each call processing block in
each subsystem.
Subsys Block Full Name Functions Processor
BCMS BTS Call & Management Subsystem BSP
(UCPA-E)
BCCB BTS Call Control Block -Processes the message related to BTS call
-Establishes ATM Cell routing
-Performs radio resource management
BSP
BHCB BTS Hand-off Control Block Hand-off processing for voice & data call BSP
BRMB BTS Resource Management Block -Resource allocation and collection for
TC/SCH and hand-off call
-Frame offset management
BSP
BTCB BTS Transparent Message Control
Block
Message handling such as Location
registration, Authentication, SMS, Order,
etc.
BSP
BPMB BTS Power Management Block Initial/periodic calibration of BTS, call
Control by electric power and electricity-
Related parameter management
BSP
DBPS Digital Baseband Processing
Subsystem
DBP
(DBPA)
PSB Pilot & Sync Channel Block Provides time information of system and
system parameter.
DBP
PCB Paging Channel Block Provides the information on system.
Provides the order on MS or Paging
DBP
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information.
ACB Access Channel Block Provides the function to allow MS to initially
recognize BTS
DBP
TCB Traffic Channel Block Provides the function to transmit/receive data DBP
3.3.2 OAM S/W
OAM function of BTS is processed around BSM S/W in hardware level. The OAM S/W to
perform OAM function, which is loaded in processor of each hardware block in BTS,performs a series of operations such as downloading, measurement & statistics, fault/status
management, power control, testing, etc., thus to transfer such operations to BSM.
The following diagram shows the OAM S/W loaded in the processor of each H/W block.
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Fig. 0-26 Functional diagram of BTS OAM S/W
The following is the table which simply shows the function of each OAM block in each
subsystem.
Subsys Block Full Name Functions Processor
BCMS BTS Call and Management Subsystem BSP
(UCPA-E)
BDLB BTS Down Loading Block Firmware and S/W loading BSP
BDHB BTS Data Handling Block BTS configuration and operational data
handling
BSP
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Chapter 3. BTS Functions
1. Call Processing
Call processing is a series of operations to allocate various system resources and connect the
proper call path so that a mobile subscriber can perform the desired communication. In
general, call processing can be classified into 3 calls such as Mobile to Mobile, Mobile to
Land and Land to Mobile according to call processing-oriented subscriber, and call
processing procedure consists of originating call set-up, incoming call set-up and clear.
STAREX-IS BTS performs the originating/incoming call processing for voice, circuit and
high/medium/low speed packet data as follows:
1.1 Voice Call Processing
STAREX-IS BTS performs the voice call processing from the voice call of 8K EVRC and
8K/13K QCELP to Mobile to Mobile, Mobile to Land and Land to Mobile respectively.
BTS sends the compressed voice signal from MS to BSC. The signal from BSC is
transmitted via SLPA and vocoding procedure of VCPA and converted into PCM signal, then
transmitted to MSC. MSC sends a subscriber voice signal as a PCM signal to BSC within a
same MSC, other MSC or PSTN, according to the subscriber type on the incoming side.
Voice call function of BTS performs the following functions:
Originating/incoming function
Quick Paging function
Reservation Access Mode, Designate Access Mode, Power Controlled
Access Mode
For detail features of voice call processing, see BSC System Description.
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1.2 Data Call Processing
CDMA2000 System can perform data call processing for low-speed(13K) / medium-
speed(64K) / high-speed(144K) packet data call and circuit data call such as Async, G3 Fax,
etc.
For this system, the procedure of packet data call processing is similar to that of general call
processing; First, the system performs the procedure of validity and authentication of
subscriber in interworking with MSC via 3G IOSv4.0 Protocol, then it connects the call
using MIP, the standard protocol on PDSN and R-P Interface, i.e., the bearer path to which
data is transmitted is not connected to MSC, but to BSC -PDSN.
The packet data, which is originated from MS and transmitted to BSC via BTS, performstermination processing of Radio Link Protocol in SLPA of BSC, and then it interfaces with
PDSN via PIP. And PDSN provides MS with internetwork connection.
During the procedure of call set-up for packet data service, the acceptance of service option
for packet data service is negotiated in the performance of service negotiation procedure. In
this case, low-speed/medium-speed/high-speed packet data is performed depending on the
system configuration and resource status.
If the MS is in Dormant status, packet paging should be processed on request, which is
performed through the service option transferred between PCF and MSC/VLR.
In case of performing packet data service, the system performs the processing depending on
each state such as Control Hold, Suspended State and Dormant State in MAC layer.
Circuit data is transferred via SLPA and VLIA, and then interfaces with MSC. In IWF, it also
performs the function to interface with signaling system of circuit connection on cable
network.
Data call function performs the following functions:
IS-2000 high-speed / medium-speed / low-speed packet data call processing
Circuit data call processing
IS-2000 Protocol processing for packet data service
For detailed features of data call processing, see BSC System Description.
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1.3 Call Admission Control
Call Admission Control is the control function to allow MSC or BTS to accept or reject the
request for wireless resource allocation in order to leverage wireless resources and maintain
high-quality service. In addition, this function also changes the property of another wireless
resource, in order to accept the request for the allocation of specific wireless resource.
Resource allocation method can be classified into two methods; wireless resource allocation
method (FA, traffic channel, Walsh code channel) and wire resource allocation method
(frame offset). BTS performs wireless resource allocation prior to wire resource allocation.
Channel assignment inquires the existence of establishable resource by performing pagingfor channel resources within system, and if there is no resource allocable, it terminates the
call. Meanwhile, if there is any resource allocable, it performs the procedure of call-related
connection. In the system, there is not any limitation of the number of packet data service
user. However, there is only limitation of total data rate available from BTS. Accordingly, if
all users request for low-speed data service, the more user can use the service than if all
users request high-speed data service.
In the software level, an operator can change the threshold for total data rate available from
BTS. However, the threshold has only the numerical limitation, which may be limited by
radio environment, total transmitted power of BTS, etc.
If radio channel resources are exhausted
If all system resources are exhausted, this informs an operator of the related information.
In occurrence of hand-off
If Target BTS has no resource, the hand-off procedure fails and the call is maintained to the
resource of Source BTS. Subsequently, if the radio environment becomes worse, the call
ultimately terminates or hard hand-off occurs between FA. Before the call terminates, Call
Admission Control continues to request for support to Target BTS. In this case, if there is
any resource available at Target BTS, this starts the procedure of resource allocation for
hand-off.
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General Call Admission Control
STAREX-IS BTS performs the following functions in order to perform Call Admission
Control.
Periodically collects the volume of total transmitted power in forward
channel and the average SIR value in backward channel for each FA/sector
in Channel Element Controller.
Identifies the usage profile of channel card, channel element and Walsh
code to check and manage the status of resource allocation.
Checks the volume of transmitted power in forward channel and the average
SIR value in backward channel available for the specific channel element, if
necessary.
STAREX-IS BTS performs Call Admission Control according to the existence of the
following: Cell load status, channel element resource for each FA/sector, Walsh resource,
transmitted power resource and wire link resource.
Each resource can be allocated, only if there is any abnormality in threshold.
FA allocation method
Classification Description
Resource allocation based on
RF resources
- RF resource means the volume of power available forwardly orbackwardly.
- This is the method that the FA with the smallest volume of forward
direction power of all FAs available in BTS is allocated to MS.
- This method is a disadvantage of the potential longer call set-up time,
because the power should be calculated with moving average for a certain
time so that BTS can correctly measure forward direction power.
Resource allocation to FA
requested by MS
- This is the method that BTS allocates resources to FA requested by MS.
- This is the simplest method of resource allocation to maximize the traffic
carrying capacity.
- If there is no BTS resource within the relevant FA/sector requested by MS,or if it is impossible to allocate resources due to alarm or fault, BTS
transfers the call to FA with the largest traffic channel available.
- In the operation of Multi-FA, this method is a disadvantage of any
potential inconsistent power ratio between FA.
Traffic channel assignment method
If the physical traffic channel is considered to be normally operated, the relevant physical
channel is managed with cue data structure in the software level. That is, BTS saves the
physical channel to cue in each order of normally operated channels. And if there is a call
request from MS, each channel is assigned at cue in regular order. Additionally, in case of
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call clear, the channel is saved to cue so that all traffic channels can be equally used.
Traffic channel management can be performed by each call such as voice call, hand-off call
and data call. Traffic channel management for hand-off call is performed according to the
traffic channel management for reserved hand-off. Data call may be processed equally as
ordinary call or may be allocated separately.
The method of separate data call allocation includes the channel reservation as hand-off call
and the channel assignment to dedicated FA.
Walsh code channel assignment
BTS performs Walsh code channel management for each Sector/FA. BTS also manages
Sector/FA-specific Walsh code as cue and for 128-Walsh code and 64-Walsh code, it
performs Walsh code channel management to lessen the number of cases of useless code due
to its collision.
Channel element assignment
Channel card performs call processing to make load volume dispersed to each FA/sector. For
some channel element block assigned for overhead channel switch-over, resource allocation
is withheld. However, resources are allocated, only if the channel element for call processing
is insufficient
Frame offset allocation (E1 link allocation)
Frame offset is used to disperse the load of trunk line. BTS has a cue structure for frame
offset in each trunk line. The frame offset should be allocated, which is used at least within
trunk line available in the assigned traffic channel. For hand-off call, the frame offset is first
allocated, followed by the traffic channel with the relevant trunk line, in order to minimize
hard hand-off between frame offsets. In case of call clear, the used frame offset is returned
onto the cue structure of relevant private line, thus to perform the resource management for
frame offset.
Call Admission Control for Data Call
In case of data call set-up, only Multiplex Option that specifies the maximum rate without
any limitation to specific speed is determined. Unless there is any special reason, Multiplex
Option accepts the matter requested from MS as it is.
Determination of radio channel speed
The optimum speed on the radio channel transmitted/received to MS is determined within
the limitation of maximum speed at the point of SCH allocation. This intends to determine
the optimum speed by synthetically judging the status of radio channel at the point of
needful SCH. BTS periodically receives the report on the strength of pilot signal, in order to
synthetically judge the status of radio channel, and it periodically measures the call load
within system. SCH allocation is enabled if necessary. However, if there is no data to
transfer, SCH is directly de-allocated. After SCH is de-allocated, low-speed data service
using FCH (Fundamental Channel) is available.
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Data call admission control
For the allocation of data call, user should determine whether to perform data call admission
in consideration of remaining volume of power in sector. After performing data call
admission, low-speed data service using FCH is first progressed. If it is necessary to increase
the speed, the optimum speed is determined in consideration of the remaining volume of
power for each sector, followed by the procedure of SCH allocation.
1.4 Channel Processing
Forward Channel
F-PICH(Forward Pilot Channel)
F-PICH features the always transmission to forward link and the non-modulation spread
spectrum signal used for the synchronization of MS within a territory of the relevant BTS.When MS is connected to CDMA network, this channel selects the largest one of all
received signals. This channel is the channel to separate cells or sectors in adjacent BTS and
to provide the phase reference for coherent demodulation, which is diffused to Walsh code 0.
F-SYNC(Forward Synchronization Channel)
F-SYNC features the channel to download different parameter information of BTS and to
upload them to MS. Based on the information received in this channel, MS synchronizes
internal MS time with the time on CDMA network. Accordingly, the signal transferred
through F-SYNC is shared with all MSs within cell. This channel is diffused to Walsh code
32.
F-PCH(Forward Paging Channel)
F-PCH is the channel to transmit a variety of messages, which include the basic information
required for the operation of MS, such as overhead message, broadcasting paging message,
channel assignment message, SSD(Shared Security Data) update message, authentication
trial message, etc.
F-QPCH(Forward Quick Paging Channel)
F-QPCH is the channel to transmit the information on whether to allow MS to supervise F-
PCH, when MS in dormant state is in slotted mode, i.e., this channel is used for the
indication of paging or in case of transferring the information on change of configurationdata, etc. to MS. This channel allows users to reduce the power consumption of MS by
lessening the time required for MS to monitor paging channel of BTS.
F-FCH(Forward Fundamental Channel)
As a type of traffic channel, F-FCH is the traffic channel to transmit voice call or low-speed
data call. In addition, Signaling can be transferred for Backward Compatibility of existing
IS-95 in this channel. The transfer rate is variable, which features 20ms frame structure.
Using this frame structure, user can transfer data at the rate of RS1(Rate Set1), RS2(Rate
Set2).
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F-SCH(Forward Supplemental Channel)
F-SCH is the additional channel in IS-2000, which features organic operation with F-FCH
and packet structure to provide high-speed data service. Unlike the Fundamental channel
available for subscribers basically, this channel is assigned separately for the relevant
subscriber for any potential increased data volume of subscriber.
F-SCCH(Forward Supplemental Code Channel)
As used only in RC1,2, F-SCCH is the channel used for transmitting subscriber data to BTS
during the calling. This channel is also available for providing MDR(Medium Data Rate)
service.
Backward Channel
R-PICH(Reverse Pilot Channel)
R-PICH is the channel for phase reference for coherent demodulation of BTS. This channel
transmits power control bit in order to perform Forward Closed Loop Power Control.
R-ACH(Reverse Access Channel)
R-ACH is the channel used for the communication between MS and BTS. This channel is
also used for transferring the short signaling message such as call originating, response to
paging, location registration, etc. The access channel is identified solely by Long code of
each MS.
R-FCH(Reverse Fundamental Channel)
R-FCH is the channel used for transferring subscriber data and control information to BTS
during the calling. This channel also features the traffic channel to transfer voice call or low-
speed data call. The transfer rate is variable, which features 20ms frame structure. Using this
frame structure, user can transfer data at the rate of RS1, RS2.
Channel configuration and operation
Overhead channel configuration
Link Channel type Quantity
Forward Pilot 1 channel/FA, sector
Sync 1 channel/FA, sector
Paging 1 channel/FA, sector
(Scalable up to 7 channels depending on capacity)
Quick Paging 1 channel/FA, sector
(Scalable up to 3 channels depending on capacity)
Backward Access 1 channel/FA, sector (Scalable depending on capacity)
Forward overhead channels such as Pilot/Sync/Paging/Quick Paging Channel and backward
channel such as Access Channel have each assigned channel element independently. BTS
assigns one channel element to each overhead channel, and if there is any occurrence of fault
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or alarm, it performs the dynamic assignment of another normal channel element.
Switch-over method in case of overhead channel fault
Overhead channel fault is identified with diagnosis function or status management function.
If there is any occurrence of fault, the overhead channel is switched over to the channel not
used for traffic channel. If the channel is switched over, the configuration information of
PLD is changed, and other informations such as the fault information are reported to BSM.
Channel element faultIf there is any fault of channel element used as overhead channel, the switch-over
to channel element available in same modem is enabled.
Model fault
If there is any fault of modem with assigned overhead channel, all overhead
channels are switched over to another available modem within the same channel
card. If it is impossible to enable switch-over to another modem, each overhead
channel is dispersedly switched over to various modems. If there is any occurrence
of modem fault, user should hold the channel assignment so that one of modems
mounted on each channel card to facilitate the switch-over of overhead channel
should not be used as a traffic channel as possible.
Channel card fault
If there is any fault in the channel card with assigned overhead channel, user
should switch all overhead channels over to available channel card. If it is
impossible to perform switch-over to another channel card, user should dispersedly
switch each overhead channel over to various channel cards. In this case, make
sure that the switched overhead channel should not be converged on a channel
card.
Channel Pooling Scheme
STAREX-IS BTS can operate traffic channel as the pooling type within a shelf, i.e.,
STAREX-IS BTS features the structure to enable pooling in all sectors and FAs used on
shelf.
If used as 6FA Omni Sector: Channel Pooling possible between 6FA
If used as 2FA/3Sector: Channel Pooling possible between 2FA
If used as 1FA/6Sector: Channel Pooling possible between 6 Sectors
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If all traffic channel resources within a shelf are used, especially for the call requiring new
channel assignment, the corresponding function is implemented so that the service of desired
call is available through the function of change from BSC to FA of another shelf for the
relevant call.
2. Location Registration Processing
Location registration is the procedure to allow MS to inform BTS of its own location, status,ID, slot cycle and other features. In this case, MS informs BTS of its own location and status
so that BTS can effectively send the call to MS, when BTS performs the set-up of incoming
call from MS.
MSC directly performs the procedure of location registration, while BSS performs the
procedure to register the location of MS onto CDMA Network by interworking with MSC
and MS or mobile terminal.
Upon the slotted mode, MS provides BTS with SLOT_CYCLE_INDEX parameter, thus to
inform BTS of the information on slot supervised by MS. MS provides BTS with its own
class and CAI revision number to allow user to check the capability of MS.
Packet zone registration, which is newly added to location registration, performs the location
registration of BSC to FA(Foreign Agent) on PDSN side for Dormant H/O between PDSN.
For detail features of location registration, see BSC System Description. Let us see the
outlined description in the following section:
2.1 Location Registration by MS
Power-Up Registration
This is the function to allow MS to perform the location registration, when MS uses another
CDMA system upon power up or MS performed system conversion from analog system tocurrent system.
Power-Down Registration
This is the function to allow MS to perform the location registration upon power down, only
if there is a location registration on the current system.
Timer Based Registration
This is the function to allow MS to perform the location registration upon the termination of
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location registration timer in MS. In this case, BTS may disable Timer Based Registration by
setting REG_PRD as 0 in the system parameter message.
Distance Based Registration
Based on the difference in latitude and longitude between two BTSs, MS calculates the
distance between the recently registered BTS and current BTS, thus to determine the
migration distance of MS. If this distance value exceeds threshold, Distance Based
Registration allows MS to perform the location registration.
Zone Based Registration
When MS is moved to the new zone not available in the list of visited location registration
zone, which MS saves on its own, Zone Based Registration is enabled. In this case(including implicit location registration), the relevant zone is saved on the list, even in the
termination of the relevant timer.
Parameter Change Registration
This is the function to allow MS to perform the location registration, when the parameter
value of MS is changed.
Packet Zone Registration
To process the packet data service, this is the function used to set the zone controlled by a
PDSN, thus to set various BTSs within such zone as the packet zone. Subsequently, MS
receives the packet zone information through expansion system parameter message from
BTS in every change of BTS. If the received packet zone is changed, MS performs Packet
Zone Registration to FA (Foreign Agent) on PDSN side to support hand-off between PDSN
in Dormant state.
2.2 Location Registration by MSC
Ordered Registration
During the call control by MSC, if it is required to perform the location registration onto
MS, this function is used to allow BTS to transmit the request order for registration to MS,
thus to perform the location registration.
Implicit Registration
If MS successfully sends the originating call or page response message, MSC can infer the
location of MS. The registration based on this principle is called Implicit Registration. In
this case, there is no message switching with MS.
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Traffic Channel Registration
This is the function to allow MSC to acquire the information of location registration on MS
with assigned traffic channel and to send the registration message to MS, thus to inform that
the location registration is performed. Accordingly, MS recognizes that the location
registration is performed through the registration message of MS, during the assignment
procedure of traffic channel.
3. Hand-off
Hand-off is the function to prevent the traffic in service from being disconnected, when a
mobile subscriber moves from the current service area to another adjacent area, in order to
enhance the quality of traffic in CDMA2000 system.
In other words, when MS moves from the serving cell (or sector) to another cell (or sector),
this means the function to change the call path to the latter cell, in order to reliably maintain
the conversation.
MS compares the threshold value for the strength of pilot channel received from BTS with
the strength of pilot channel in another adjacent BTS, which MS continues to measure. In
some point of time, especially if the comparison value of these measurements shows the
value required for hand-off, MS reports it to CDMA system and performs hand-off under the
control of relevant system depending on the type of hand-off.
Hand-off algorithm of CDMA2000 Network complies with TIA/EIA/IS-2000 and IOS v4.0,
and STAREX-IS BTS performs the function to control the hand-off signal.
For detail functions of hand-off, see BSC System Description. Here we will see the outlined
description on the type of hand-off.
3.1 Types of hand-off
Hand-off is classified into the following 3 types : Softer Hand-off, Soft Hand-off and Hard
Hand-off depending upon an usage relation of cell resources between serving cell and
adjacent cell, system configuration of the adjacent cell and hand-off timing.
Soft Hand-off is, based upon system configurations in two BTSs, classified into inter-BTS
soft within a BSC and inter-BTS soft between remote BSC.
Hard Hand-off is, within the same MSC, subdivided into a Hard Hand-off generated by
Frequency modulation or Frame offset change between neighboring BTSs or inter-BTS with
neighboring BSC, a Hard Hand-off between different type of BSCs and a Hard Hand-off
generated between neighboring MSCs.
Soft H/P functions for the BSCs to be connected through CAN and thus Soft Hand-off to be
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available for the Hand-off generated within a MSC.
The newly added Hand-off in CDMA 2000 System, in comparison with the existing system,
provides with an Access Hand-off for MS to reduce the setup failure ratio, a Dynamic
Threshold Soft Hand-off to prevent frequent Add/Drop and various Hand-off functions.
Softer Hand-off
Softer Hand-off is a kind of Soft Hand-off which is generated when mobile terminal is
moving between sectors with same frequency within a BTS. Softer Hand-off, depending
upon procedure and management type of pilot offset list that MS retains, is operated in 3ways, i.e., ADD, DROP and SWAP.
Soft Hand-off
Soft Hand-off is generated when moving between BTSs within a same MSC with a same
frame offset. Soft Hand-off of inter-BTS is also, depending upon procedure and management
type of pilot offset list that MS retains, operated in 3 ways, i.e., ADD, DROP and SWAP.
To perform the Soft Hand-off function between BSC, the controlling signal route and the
traffic route for the whole inter-BSC controllers are prepared by way of CAN.
Hard Hand-off
Hard Hand-off generates in some cases when performing hand-off by altering frequency or
frame offset while moving to different BTS, when hand-off generated between different
types of BSC, and when the switch of MSC is temporarily disconnected while hand-off
between MSCs.
Access Hand-off
Access Hand-off is generated when mobile terminal moves into another cell while call
setting up.Access Entry Hand-off, before MT gets into Access Status, changes the page supervising
BTS.
Dynamic Threshold Soft Hand-off
It is an enhanced feature of Soft Hand-off that set up the only sufficiently powered pilot
signal as the Active Set to put radio channel resources into efficient use. Hand-off control
function that performed in BSC, works similar to the control function using Static
Threshold.
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Enhanced Hard Hand-off
The Enhanced Hard Hand-off, in case when MT measures the strength of pilot signal in
adjacent FA as well as the FA currently set and senses FA in better environment, is a function
that performs hand-off in relevant FA.
Inter PDSN Dormant Hand-off
Inter PDSN Dormant Hand-off works when a terminal made a move of PDSN service area
in dormant status.
3.2 Voice Call Hand-off
Softer Hand-off between sectors
Soft hand-off between sectors is one of soft hand-off types and is generated when the mobile
terminal moves within the same MSC, BSC, and BTS with same frequency.
Inter-Frequency Hard Hand-off
In CDMA inter-frequency hand-off in the same BTS, if the neighboring pilot is operatedwith frequency other than those of current call, and when the BTS where the call is set up
operates the frequency of neighboring BTS, it can hand off by using the frequency used in
the neighboring BTS within the BTS.
Inter Frame Offset Hard Hand-off
Hard hand-off causes instantaneous call disconnection due to change of frequency and is
generated in case of hand-off between different CDMA channels in neighboring BTSs or
hand-off between different Frame Offsets.
Intra BSC Soft Hand-off
Generated when moving between BTSs within the same exchange with same frequency and
same frame.
Inter BSC Soft Hand-off
For implementation of soft hand-off function between controller of BTS, control signal route
and traffic route between controllers of all BTSs are prepared through CAN.
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I