COMBA RX-8123 User manual

INSTALLATION GUIDE FOR RX-8123
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INSTALLATION GUIDE
The information contained herein is the
responsibility of and is approved by the
following, to whom all enquiries should
be directed in the first instance:
Comba Telecom Ltd.
This is an unpublished work the copyright in which vests in Comba International ("Comba"). All rights reserved.
The information contained herein is confidential and the property of Comba and is supplied without liability for errors or
omissions. No part may be reproduced, disclosed or used except as authorised by contract or other written permission. The
copyright and the foregoing restriction on reproduction and use extend to all media in which the information may be embodied.
RX-8123
WCDMA 850MHZ DIGITAL WIRELESS
SELECTIVE REPEATER

INSTALLATION GUIDE FOR RX-8123
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0.2 CONTENTS
Section Page
0.2CONTENTS........................................................................................................................... 2
0.3INDEX TO FIGURES AND TABLES ..................................................................................... 4
0.4HISTORY............................................................................................................................... 5
0.5GLOSSARY OF TERMS ....................................................................................................... 6
0.6SAFETY NOTICES AND ADMONISHMENTS...................................................................... 7
1GENERAL INFORMATION ................................................................................................... 8
2EQUIPMENT DESCRIPTION................................................................................................ 9
2.1SYSTEM DIAGRAM .............................................................................................................. 9
2.2EQUIPMENT LAYOUT........................................................................................................ 10
2.3EQUIPMENT CONSTITUTION ........................................................................................... 11
2.4KIT OF PARTS .................................................................................................................... 12
3INSTALLATION ................................................................................................................... 13
3.1WARNINGS AND ALERTS ................................................................................................. 13
3.2SITE PLANNING CONSIDERATIONS................................................................................ 14
3.3INSTALLATION PROCEDURES ........................................................................................ 15
3.3.1GOODS INWARDS INSPECTION ...................................................................................... 15
3.3.2TOOLS................................................................................................................................. 15
3.3.3PREPARATION...................................................................................................................15
3.3.4WALL MOUNTING .............................................................................................................. 16
3.3.5POLE MOUNTING OF MOUNTING RACK......................................................................... 17
3.4EQUIPMENT CONNECTORS ............................................................................................ 18
3.4.1CONNECTORS ...................................................................................................................18
3.5CONNECTION ....................................................................................................................18
3.5.1GROUNDING CONNECTION............................................................................................. 18
3.5.2LI-ION BATTERY CONNECTION ....................................................................................... 18
3.5.3RF CONNECTION............................................................................................................... 19
3.5.4MISPLACE ALARM CONNECTION.................................................................................... 19
3.5.5EXTERNAL ALARM CONNECTION................................................................................... 19
3.5.6CONNECTION BETWEEN PC AND EQUIPMENT ............................................................ 19
4COMMISSIONING............................................................................................................... 20
4.1PRE-COMMISSIONING TASKS ......................................................................................... 20
4.2LED INDICATORS .............................................................................................................. 20
4.3DOWNLINK OUTPUT POWER COMMISSIONING ........................................................... 20
4.4UPLINK CONFIGURATION ................................................................................................ 20
4.5COMMISSIONING PROCEDURES .................................................................................... 21
5OMT..................................................................................................................................... 22
5.1LOCAL AND REMOTE CONNECTIONS TO OMT............................................................. 22
5.1.1LOCAL CONNECTION TO OMT ........................................................................................ 22
5.1.2REMOTE CONNECTION TO OMT..................................................................................... 23
5.2OMT CONFIGURATION ..................................................................................................... 23
5.3RF PARAMETER ................................................................................................................ 24
5.3.1SWITCH...............................................................................................................................24
5.3.2CHANNEL NO. .................................................................................................................... 25
5.3.3ATT ...................................................................................................................................... 25
5.3.4ALARM THRESHOLD ......................................................................................................... 26
5.3.5ALARM INFORMATION ...................................................................................................... 26
5.4PROPERTIES INFO............................................................................................................ 27
5.4.1EQUIPMENT ID................................................................................................................... 27

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5.4.2COMM. CONFIG .................................................................................................................28
6MAINTENANCE ..................................................................................................................29
7APPENDICES...................................................................................................................... 30
7.1APPENDIXA: TOOLS FOR INSTALLATION AND MAINTENANCE .................................. 30
7.2APPENDIXB: SERVICING POLICY AND RETURN OF EQUIPMENT .............................. 31
7.3APPENDIX C: RMA (RETURN MATERIAL AUTHORIZATION) FORM............................. 32

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0.3 INDEX TO FIGURES AND TABLES
Figure 1: RX-8123 System Diagram.............................................................................................................9
Figure 2: Front, Side and Bottom Views of Equipment.............................................................................. 10
Figure 3: Equipment Internal Layout.......................................................................................................... 11
Figure 4: Mounting Rack Overview............................................................................................................ 15
Figure 5: Wall Mounting ............................................................................................................................. 16
Figure 6: Pole Mounting Overview............................................................................................................. 17
Figure 7: Bottom Panel Interface Diagram ................................................................................................ 18
Figure 8: The Connection between Equipment and PC ............................................................................ 19
Figure 9: Commissioning Procedure ......................................................................................................... 21
Figure 10: Connection Type....................................................................................................................... 22
Figure 11: Serial Port Configuration........................................................................................................... 22
Figure 12: Remote Connection .................................................................................................................. 23
Figure 13: OMT Main Window ................................................................................................................... 24
Figure 14: Switch ....................................................................................................................................... 24
Figure 15: Channel No............................................................................................................................... 25
Figure 16: Frequency Calculator................................................................................................................ 25
Figure 17: ATT ........................................................................................................................................... 25
Figure 18: Alarm Threshold ....................................................................................................................... 26
Figure 19: Master Alarm ............................................................................................................................ 26
Figure 20: External Alarm .......................................................................................................................... 27
Figure 21: Equipment ID ............................................................................................................................ 27
Figure 22: Com. Config.............................................................................................................................. 28

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0.4 HISTORY
Change No. ENU Details Of Change
1 1-0-0 RX-8123 WCDMA user manual first created in Oct 2010

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0.5 GLOSSARY OF TERMS
ALC Automatic Level Control
ATT Attenuation
AFC Antenna Feedback Cancellation
BTS Base Transceiver Station
CSA Cross Sectional Area
dB Decibel
dBm Decibels relative to 1 milliwatt
DL Downlink
DPX Duplexer
DT Donor Terminal
E/O, O/E Electrical/Optical, Optical/Electrical
FSK Frequency Shift Keying
FOU Fiber Optical Unit
GSM Global Standard for Mobile Communication
Hz Hertz
ID Identification
LNA Low Noise Amplifier
MCU Main Control Unit
MHz Megahertz
MT Mobile Terminal
MTBF Mean Time Between Failures
NF Noise Figure
OMC Operation & Maintenance Center
OMT Operation & Maintenance Terminal
OP Optical Fiber
PA Power Amplifier
PLL Phase Locked Loop
PSU Power Supply Unit
RF Radio Frequency
RFU Radio Frequency Unit
RX Receive
SMA Sub-Miniature “A” Connector
SIU Slide-In-Unit
TX Transmit
UL Uplink
VAC Volts Alternating Current
VSWR Voltage Standing Wave Ratio
WDM Wavelength Division Multiplexer
WCDMA Wide Band Code Division Multi Access

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0.6 SAFETY NOTICES AND ADMONISHMENTS
This document contains safety notices in accordance with appropriate standards. In the interests of
conformity with the territory standards for the country concerned, the equivalent territorial admonishments
are also shown.
Any installation, adjustment, maintenance and repair of the equipment must only be carried out by trained,
authorized personnel. At all times, personnel must comply with any safety notices and instructions.
Specific hazards are indicated by symbol labels on or near the affected parts of the equipment. The
labels conform to international standards, are triangular in shape, and are coloured black on a yellow
background. An informative text label may accompany the symbol label.
Hazard labeling is supplemented by safety notices in the appropriate equipment manual. These notices
contain additional information on the nature of the hazard and may also specify precautions.
Warning:
These draw the attention of personnel to hazards that may cause death or injury to the operator or others.
Examples of use are cases of high voltage, laser emission, toxic substances, point of high temperature,
etc.
Alert:
These draw the attention of personnel to hazards that may cause damage to the equipment. An example
of use is the case of static electricity hazard.
Caution notices may also be used in the handbook to draw attention to matters that do not constitute a
risk of causing damage to the equipment but where there is a possibility of seriously impairing its
performance, e.g. by mishandling or gross maladjustment. Warnings and Cautions within the main text
do not incorporate labels and may be in shortened form.
End of Section

INSTALLATION GUIDE FOR RX-8123
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1 GENERAL INFORMATION
The RX-8123 WCDMA 850MHz digital wireless selective repeater is designed for WCDMA 850MHz
networks. It can wireless transmit, two-way amplify WCDMA uplink and downlink signals and is designed
for eliminating communicational coverage blind spots. By using the new Comba AFC (Antenna Feedback
Cancellation) technique, the system isolation tolerance has been greatly improved: Imax>G-15dB, which
was obliged to be higher than G+15dB under conventional technique.
Repeater with digital filter can efficiently limit out-of-band spurious, amplify BS signal, avoid adjacent
sector interference and extend signal coverage.
Characteristics of RX-8123 are as follows:
•Supports multiple carriers. Uplink and downlink with digital carrier selective frequency can efficiently
amplify BS signal.
•20W downlink output power.
•With AFC function
•Adopt high linear PA and ensure WCDMA signal efficiently being amplified.
•With out-of- band suppression and supports automatic gain temperature compensation function
which can maintain regular operation among working temperature.
•Local Operation and Maintenance Terminal (OMT): operating status and parameters can be set or
monitored by OMT PC locally. It can also check the downlink power and download the latest OMT
version.
•Operation Maintenance Center (OMC): system working parameters and communication configuration
can be set or inquired remotely through the integrated wireless modem. If alarm is generated, the
equipment will dial up to OMC automatically in the mode of SMS or datalink.
•Build-in Li-ion battery ensures that alarm information can automatically report to OMC in case of
equipment outage can the equipment be maintained in time.
•Chassis with cast aluminum sealed enclosure, high efficiency heat diffusion design, effective
waterproof, damp proof and antisepsis can capable for 24 hours outdoor operation.
End of Section

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2 EQUIPMENT DESCRIPTION
2.1 SYSTEM DIAGRAM
Figure 1: RX-8123 System Diagram
As shown in the above figure, the downlink BS signals go through DT port to the system and then to
downlink by duplexer separation. The DL signals will go through DT duplexer then to AFC digital
processing module for digital filtering and self-oscillation elimination. Then the DL signals will be sent to
downlink PA to amplify power and filter via duplexer. After amplification, the signals are transmitted at the
MT port to the service antenna.
On the UL, the signals transmitted by the mobile go through MT integration duplexer and AFC digital
processing module then to uplink PA to power amplify and filter via duplexer, finally get back to BS by
donor antenna.

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2.2 EQUIPMENT LAYOUT
Refer to the below figure for the equipment enclosure size:
372
492
POWER MODEM ALARM
DT MT
228
276
Figure 2: Front, Side and Bottom Views of Equipment

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2.3 EQUIPMENT CONSTITUTION
The RX-8123 consists of AFC digital module, UL/DL PA, DT/MT duplexer, MCU, distribution board, PSU
surge arrester and Li-ion battery that comprise of the modules described below:
MT
DPX
DT
DPX
DL PA
UL PA
Surge
Arrestor
MODEM
AFC Digital
Module
Distribution Board
PSU
Figure 3: Equipment Internal Layout
Name Description
AFC Digital Module
LNA
Frequency Conversion Unit,
IF unit
Can sampling, quantization and
numbering and transmit BS
signal into digital base band
signal.
Digital Processing Module Processes and filters base band
data
AFC unit
Supports digital adaptive
process, counteracts oscillation
signal and base-banded selects
useful signals
Uplink/Downlink PA Amplifier uplink and downlink
power
DT/MT Duplexer Realize UL/DL TX and RX
isolation
Distribution Board
Serves as a distributor for power
and internal communication
within the equipment
MCU
is used to monitor and control the
operation, it also provide
communication interfaces for
remote control and supervision
PSU
Converts the input voltage into a
stable DC to provide power for
other modules
Li-ion Battery
Provides power to the Main
Control Unit to send alarm
signals in the event of power
failure

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2.4 KIT OF PARTS
For this system, the following are shipped:
Product Identifier Description Quantity
RX-8123 QI This equipment manual on CD-Rom 1
Mounting Rack RRU-040L-5811 1
Power Supply Cable 4m 1
Fuse Delay fuse for PSU 2
Key N/A 2
Local Commissioning Cable R-9122C/R-9122AC 1
M10×110 Masonry Bolt 1
M10 x 85 x 110 U Bolt (with 2 nuts, flat washer, spring
washer per bolt) 2
5.5mm Allen Key 1
OMT-D OMT software on CD-Rom 1
Factory Test Report N/A 1
Table 1: Equipment KOP
End of Section

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3 INSTALLATION
3.1 WARNINGS AND ALERTS
Radio Frequency Energies
There may be situations, particularly for workplace environments near high-powered RF sources, where
recommended limits for safe exposure of human beings to RF energy could be exceeded. In such cases,
restrictive measures or actions may be necessary to ensure the safe use of RF energy.
High Voltage
The equipment has been designed and constructed to prevent, as far as reasonably, practicable danger.
Any work activity on or near equipment involving installation, operation or maintenance must be, as far as
reasonably, free from danger.
Where there is a risk of damage to electrical systems involving adverse weather, extreme temperatures,
wet, corrosive or dirty conditions, flammable or explosive atmospheres, the system must be suitably
installed to prevent danger.
Protective Earthing
Equipment provided for the purpose of protecting individuals from electrical risk must be suitable for the
purpose and properly maintained and used.
Handling Precautions
This covers a range of activities including lifting, lowering, pushing, pulling, carrying, moving, holding or
restraining an object, animal or person. It also covers activities that require the use of force or effort, such
as pulling a lever, or operating power tools.
Electrostatic Discharge (ESD)
Observe standard precautions for handling ESD-sensitive devices. Assume that all solid-state electronic
devices are ESD-sensitive. Ensure the use of a grounded wrist strap or equivalent while working with
ESD-sensitive devices. Transport, store, and handle ESD-sensitive devices in static-safe environments.

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3.2 SITE PLANNING CONSIDERATIONS
Site Considerations
The site considerations are listed below:
•The distance between the donor antenna and the BS should satisfy line of sight requirements for
maximum coverage area. The received spots accept field intensity at least -70dBm.
•Make sure that TX and RX antennas isolation should more than the max gain that of -15dB.
•Supply power near by the BS and easily access to the grounding spot.
Installation Location
Mounting surface shall be capable of supporting the weight of the equipment.
In order to avoid electromagnetic interference, a proper Mounting location must be selected to minimize
interference from electromagnetic sources such as large electrical equipment.
Chassis output interface should install higher 1.2m than the ground.
Environmental
Humidity has an adverse effect on the reliability of the equipment. It is recommended to install the
equipment in locations having stable temperature and unrestricted air-flow which should under the
temperature that of 0oC ~40oC and relative humidity of maximal 85%.
The installation location for the product should be well ventilated. The equipment has been designed to
operate at the temperature range and humidity level as stated in the product specifications in the
datasheet.
Direct sun light exposure to the equipment should be avoided. Provide additional shelter if necessary.
Powering
The power supply unit (PSU) provides power to all modules within the equipment. Depending on the
product variant, it is recommended that the PSU operates on a dedicated circuit breaker or fused circuit.
Meanwhile, the alternating current should be form 85V to 264V and from 45Hz to 55Hz.
Grounding Requirement
Verify that the equipment has been well grounded. This includes antennas and all cables connected to
the system. Ensure lightning protection for the antennas is properly grounded.
Cable Routing
Depending on equipment configuration, a variety of types of cables are required. Where applicable,
ensure cables are properly routed and secured so that they are not damaged.
Cable requirements are as follow:
NAME CONNECTION DESCRIPTION
Coaxial Cable 1 N to N Connect BS cable to DT port
Coaxial Cable 2 N to N Connect serve antenna cable
to MT port
RS 232 Cable RS 232
Table 2: Cable Connection
Manual Handling
During transportation and installation, take necessary handling precautions to avoid potential physical
injury to the installation personnel and the equipment.

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3.3 INSTALLATION PROCEDURES
3.3.1 GOODS INWARDS INSPECTION
1. Verify the number of packages received against the packing list.
2. Check all packages for external damage; report any external damage to the shipping courier. If there
is damage, a shipping agent should be present before unpacking and inspecting the contents
because damage caused during transit is the responsibility of the agent.
3. Open and check each package against the packing list. If any items are missing, please contact
Comba.
4. Do not remove items from antistatic packing until ready for installation. If damage is discovered at the
time of installation, contact the shipping agent.
3.3.2 TOOLS
See Appendix A for a full list of the recommended tools required for installation and maintenance.
3.3.3 PREPARATION
zWall mounting with the masonry bolts supplied, which make use of the outer holes.
zPole Mounting with the clamp kit supplied, which make use of the inner holes.
For Wall Mounting
For Pole Mounting
402
200
85
8- 13
Figure 4: Mounting Rack Overview

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3.3.4 WALL MOUNTING
zDrill holes on the wall by using the position of the four round holes on the Mounting rack as a guide.
zInsert the masonry bolts M10x110 through the round holes and tighten them to take the weight of
the entire enclosure.
zHook the enclosure up onto the mounting rack and align the hole positions to that of the mounting
rack, then installed the hex socked bolt (M8 x 20) to complete the installation.
Plain
Washer
Spring
Washer
Masonry Bolt
M10
Spring Washer
Mounting Rack
Hex Socket Bolt
M8x20 (5.5)
Plain Washer
Figure 5: Wall Mounting

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3.3.5 POLE MOUNTING OF MOUNTING RACK
zSee figure4 and drill the holes for pole mounting preparation.
zSecure the Mounting rack onto the pole using masonry bolts (M10 x 10).
zHook the enclosure up onto the mounting rack and align the hole positions to that of the mounting
rack, then installed the side bolts.
zUse spanner to tighten hex socket bolts (M8 x 10) to mounting rack to complete the installation.
Hex Socket Bolt M8x20 (5.5)
U-Bolt M10x85x110
Spring Washer
Flat Washer
Flat Washer
Spring Washer
Nut M10
Mounting Rack
Pole
Side Bolt
Figure 6: Pole Mounting Overview

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3.4 EQUIPMENT CONNECTORS
3.4.1 CONNECTORS
ALARM
MODEM
POWER
DT MT
Figure 7: Bottom Panel Interface Diagram
The connection interfaces are shown below:
Connector Description
MT N-female connector, for external mobile antenna
DT N-female connector, for external donor antenna
Power1Power Supply Interface
Alarm External Alarm Interface , 7 pin CPC
MDM SMA-KYK connector for Modem antenna
Table 3: Bottom Panel Interface
3.5 CONNECTION
3.5.1 GROUNDING CONNECTION
Ground Connection
To ensure safe operation of the product, a ground (earth) connection is required. For single phase AC
power source, the product must be grounded by connecting the “earth wire” of the power cord to the
ground terminal of the AC supply.
3.5.2 LI-ION BATTERY CONNECTION
Li-ion battery is provided with this system to ensure power is supplied to the system monitoring unit and
MCU and to ensure the alarm message could be sent to OMC effectively in case of mains power failure.
Caution: Be careful of the risk of explosion if battery is replaced by an incorrect type. Dispose of used
batteries according to the instructions.
1The voltage identification is a variant due to electricity system diversity of global regions. The power cable gland
might be identified for AC 220V, AC 110V, AC 220V/110V, DC -48V, or DC +24V respectively. Please refer to
specific product or contact local sales if any doubt.

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3.5.3 RF CONNECTION
zDonor antenna connection: Connect the cable form donor antenna to DT port
zMobile antenna connection: Connect the cable form mobile antenna to MT port
3.5.4 MISPLACE ALARM CONNECTION
Introduce a misplace alarm cable to CPC which marks “ON/MOV”. Make sure that the misplace cable
connect with protection ground. Do not connect with the chassis to realize misplace alarm.
3.5.5 EXTERNAL ALARM CONNECTION
The external alarm port is used to connect with other external equipment and alarm ports. Connection is
not must in case there is no external alarm port.
3.5.6 CONNECTION BETWEEN PC AND EQUIPMENT
The below shows the connection:
RS-232
GSM
Network/PSTN
wireless
Build-in
GSM
Modern
Realize remote
monitor
Local Monitoring
wire/wireless M
Monitoring Center O
RS232 cable
Figure 8: The Connection between Equipment and PC
End of Section

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4 COMMISSIONING
4.1 PRE-COMMISSIONING TASKS
After equipment installation, perform the following steps before equipment powering and commissioning,
check that the expected voltage, current, and power levels do not violate any ratings. Double check all
connections including ground before applying power. Do not manipulate circuits or make changes when
power is applied:
•Visually inspect the power connection within the equipment. Ensure that the power cable is correctly
and securely connected, including grounding wire, RF cable and optical cable.
•Check grounding connection and verify that the ground resistance is less than 5Ω.
•Connect the equipment to the PC installed with OMT software.
•Check antenna system return loss which working frequency band return loss should less than -14dB
(VSWR < 1.5)
•The online commissioning can be commenced with following the commissioning steps.
4.2 LED INDICATORS
Diagnostic LEDs are located on the distribution board, with each indicating the status of a particular
function:
Identifier Colour Indication
LED 2 Green Operation indicator – fleshes once after powering.
LED 3 Red Modem status indicator. Flashes during initiating, and go off after that. If the
indicator is continuous on then the initiating fails.
LED 4 Red Alarm indicator. ON = alarm; OFF = no alarm
LED 5 Green Operating indicator and Flashes once every second to indicate normal
monitoring.
Table 4: MCU LED indicators
The LEDs RUN, ALM, will flash simultaneously three times during system self-checking after equipment
power-up. Then, RUN flashes every second to indicate system commissioning can proceed.
4.3 DOWNLINK OUTPUT POWER COMMISSIONING
Read the downlink output power parameter via local or remote connection. Adjust the master or remote
unit downlink ATT to get the coverage requirement. Aware that input power overload will impact on call
quality.
4.4 UPLINK CONFIGURATION
Change uplink gain via local or remote uplink ATT to make UL/DL balance. Minimize the uplink output
noise level which will impact on BTS to optimize the coverage.