WR_TS02_E1_0 ZXWR Node B Maintenance 86

WR_TS02_E1_0 ZXWR Node B Maintenance

ZTE CORPORATION ZTE Plaza, Keji Road South, Hi-Tech Industrial Park, Nanshan District, Shenzhen, P. R. China 518057 Tel: (86) 755 26771900 800-9830-9830 Fax: (86) 755 26772236 URL: http://support.zte.com.cn E-mail: [email protected]

Contents

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Chapter 1 1

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Appendix A 79

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Confidential and Proprietary Information of ZTE CORPORATION 1

C h a p t e r 1

Maintenance Overview

This chapter introduces common maintenance types, maintenance principles and analysis methods and provides precautions for routine maintenance.

Maintenance Description

Maintenance Requirements

Maintenance personnel must receive systematic training to be qualified in system maintenance, master fundamentals of ZXWR B09, and know overall structure and functions of each board, in addition to some knowledge about network optimization and network maintenance.

Maintenance Principles This section introduces what maintenance personnel must pay attention to in ZXWR B09 maintenance. Any operation against following principles may have a negative impact on system operation.

Right Management

Assign personnel-specific usernames and passwords for system login, operation and maintenance, to restrict operation rights of maintenance individuals and find operation history through system logs in case of system malfunction.

Different users are able to perform different groups of operations, depending on their levels and rights. Operation and


2 Confidential and Proprietary Information of ZTE CORPORATION

maintenance software classifies operators into four levels, root user, advanced user, medium-level user, and ordinary user in descending order of rights.

1. Root user, with highest level of right, can perform any operations, including creating users, modifying user information, deleting users, setting rights and modifying system configuration. Change initial password of root user immediately after logging in to the system, for security of the system

2. Advanced user has the same rights as a root user, except that it cannot manage user accounts, add/delete boards and add/delete local cells.

3. Medium-level user, with basic viewing right, can view alarm and system information. In addition, a medium-level user can only perform limited types of configuration operations.

4. Ordinary user, with lowest right, can only view information rather than perform any configuration operation.

Caution

Use right management function to set ordinary equipment maintenance personnel as medium-level users.

Do not log into the system as root user unless absolutely necessary.

Do not change network settings of NMS server and Client.

Do not run and operate any other programs not related to operation and maintenance on NMS server or Client.

Follow general principles of network management to guard against any virus.

Data Observation

Caution

Perform data observation operations carefully with large quantities of data to report, including signaling tracing, running information observation, all users of service observation, and alarm refreshing. Excessive data report during data observation may cause system breakdown in extreme cases.

Caution

Select appropriate time (low traffic period) for data observation operation, take appropriate measures, save results in time and clean temporary data in time.

Chapter 1 Maintenance Overview


Data Modification

Caution

Take care in modifying data, particularly wireless data.

Observe carefully whether there is any effect on system operation after modifying data.

Caution

Be sure to perform backup before modifying any data, to ensure rapid restoration when any problem occurs.

Do not perform data synchronization at rush hours (at 10 AM or 5 PM, Time varies from place to place).

Do not modify foreground database during daytime.

Data Synchronization

Caution

Be sure to backup data before modifying configuration.

Caution

Do not perform data synchronization in daytime unless necessary.

Check operation log to identify the source if finding any data of an unknown source.

Man-machine Commands

Caution

Be careful in using commands that lead to foreground actions, including restart, reset, changeover, save, hardware test, software download and cell block/unblock.

Do not delete current alarms and history alarms unless absolutely necessary.

Be sure to lock background man-machine interface after maintenance personnel leave operation and maintenance console, to avoid any accidents.



Board Operations

Caution

Do not reset a board, plug/unplug it or power it off unless absolutely necessary.

Prepare spare board before replacing a board. Make sure there are sufficient technicians present for unexpected emergencies in the case of major operations, such as changing versions of important boards, or plugging, unplugging and replacing key boards. Maintenance personnel working on boards in the foreground must have support from background personnel.

Caution:

Always wear an antistatic wrist strap before operating boards on the rack and connect it to the rack before touching a board.

Touch a metal object first to release static electricity on hands.

Reduce power gradually (to change users in conversation or in network access and to prevent users off-conversation from accessing) when replacing LPA (Linear Power Amplifier).

Update

Caution

Perform upgrade at midnight when there is low traffic.

Keep contact information available for relevant personnel (like transmission and power supply) to get their timely assistance when required.

Formulate upgrade plan in advance, covering all emergency measures.

Do not change procedures set forth in the plan, unless necessary.

Inform supervisors before upgrading for necessary technical support.

Assign a person to closely monitor the system for any faults occurring since the upgrade.



Maintenance Classification Maintenance falls into routine maintenance, notification message handling, alarm message handling and troubleshooting, by contents.

1. Routine maintenance

Routine maintenance refers to checking equipment running status periodically. It is to find out and handle problems in time to prevent potential damage or fault.

2. Notification message handling

Notification message handling is to analyze all kinds of notifications during running of the system, to judge whether anything is abnormal and to take appropriate measures.

3. Alarm message handling

Alarm message handling is to analyze different alarm messages during running of the equipment, to judge equipment running condition and to take appropriate measures.

4. Troubleshooting

Troubleshooting is to analyze, handle and remove detected faults.

Analysis Methods Common maintenance analysis methods:

Analysis of indicator status

Analysis of signalling tracing

Analysis of alarm logs

Analysis through instruments and meters

Comparison by replacement

Others

Indicator Status Analysis

Analyze running of a board by statuses of its indicators.

Boards need frequent observation, for the ZXWR B09, are: control clock switching board CCS, Iub-ATM interface board IIA, baseband processing board BP and transceiver unit TRXU.



Signaling Tracing Analysis

Signaling tracing analysis is to check whether signaling flow is correct. All services have their own signaling flows. It is acceptable to diagnose system problems according to experience by viewing differences between current flow and correct flow, when a service is abnormal.

Important workflow, for the ZXWR B09, includes: cell setup, common transmission channel setup, paging, random access, system information update and wireless link setup.

Alarm Logs Analysis

Alarm log analysis is to query history alarms and current alarms of the system at NM interface, and to analyze and determine running status of the equipment. Instruments and Meters Analysis

Commonly-used instruments and meters in routine maintenance include signaling meters, line testers and power meters.

Signaling Meter Analysis

Signaling meter is to monitor signaling interaction between Node B and RNC in real time. Figure 1 shows the connection mode of signaling meter with the equipment.



FI G U R E 1 AP P L I C AT I O N O F S I G N AL L I N G M E T E R AT RNS

RNC

RNC

Node B

Node B

Laptop computer

1

2

90%

100%

10%

100%90

%Optical splitter

Signaling meter

10%

RNC and Node B setup several AAL5 links to bear ALCAP, common NBAP, dedicated NBAP and IPoA after powering on the equipment. It is acceptable to query VPI and VCI corresponding to each AAL5 link from OMC background man-machine interface. It is also acceptable to monitor signaling of corresponding AAL5 link after configuring appropriate VPI and VCI on signaling meter.

Set up appropriate VPI, VCI and CID on signaling meter, when AAL2 bears common transport channels (FACH, PCH, and RACH) and DCH and observes AAL2 signaling. Similarly, it is acceptable to query its signaling from WOMCR background man-machine interface. Signaling meter can resolve RRC message of Uu interface and non-access layer messages.

Signaling meter analysis allows monitoring signaling flows between Node B, RNC and UE in real time and saving results.

Line Tester Measurement

Line tester supports:

1. To measure information of common channels.

2. To measure related items in coverage area, such as locations, signal strength and signal quality.

3. To measure energy of each synchronization code in each timeslot on synchronization channel.



4. To measure channel power.

5. To measure scramble of the cell.

Power Meter Measurement

Power meter is to measure output power of TRXU and LPA and to judge whether TRXU and LPA are working normally.

Replacement Analysis

Replace a board module or possibly a faulty connection cable with a normal board module or connection cable of same type, and observe whether the fault is recovered after the replacement.

Use the following replacement analysis methods to rectify faulty boards or a subsystem.

Active/Standby Switchover

This method applies to active and standby boards configured on the ZXWR B09 rack, such as CCS.

Operate on background man-machine interface or press active/standby switchover key on front panel of the board to reset the board and to trigger active/standby switchover function.

Perform a switchover again when traffic is light and observe whether system is normal if the system recovers after active/standby switchover. Circuit or interface of currently active board may fail if system is not normal. Replace it and perform further tests.

Board Resource Block

This method applies to BP.

Block, possibly a faulty BP and check the working status of the system. Fault resides in BP or interface of the board if system recovers. Replace the board, unblock it and perform further tests.

Slot Exchange

This method applies to BP and TRXU. There is need to configure multiple BPs and TRUXs on the ZXWR B09 rack.



Exchange slot of a normal board with a possibly faulty board, and check working states of boards to determine whether fault resides in the board or interface of the board.

Board Replacement

This method applies to EMU and TRXU configured for single carrier and single fan. Directly replace a possibly faulty board with a new board verified as normal.

Cable Replacement

Cables that easily fail include TRXU RF cable, IIA port fiber/E1 line and rack fan connection line. Specific method:

1. Connect RF cable of the TRXU, parts of which are possibly faulty, to DDL of another normal cell, and check status of the cell. TRXU and related parts are normal if the cell is still normal. Otherwise, replace them.

2. Remove connected optical fiber and check it through self-loop if an optical interface of IIA is blocked. This optical interface is faulty if self-check is abnormal. Connect the fiber to another available optical interface of IIA and reconfigure the data. Replace the optical fiber or check peer equipment if the other optical interface is found normal in self-loop test.

Caution

Do not direct optical fiber interface to eyes, this may result in a serious injury.

Do not look at IIA board optical interface directly, this may result in a serious injury.

It is very difficult to remove fans on the rack. Check power cable first by connecting it to another slot or using other methods when finding that a fan is not working normally.

Precautions

Personnel Qualifications

Maintenance personnel must receive pre-service training to learn necessary knowledge about the equipment and related network, and they must follow instructions given in related manuals of the ZXWR B09 to conduct maintenance.

Maintenance personnel must have earnest attitudes and high competence.



Maintenance Management

Make a complete set of equipment room maintenance regulations to standardize daily work of the maintenance personnel. Forbid non-maintenance management personnel to perform any maintenance operation.

Make a detailed on-duty log to provide detailed records about system running, version status, data change, upgrade and problem handling for easy analysis and troubleshooting once any fault occurs.

Make a work shift record to clearly define responsibilities.

Do not play games or access the Internet through computer terminal. Do not install, run and copy any other software not related to the system at the terminal. Do not use the computer terminal for other purposes.

Set NM passwords by level. Put them under strict management and change them periodically so that they are only accessible to maintenance personnel.

Data Maintenance

Do not reset the equipment, load or change any data unless absolutely necessary. Do not change background database at will.

Backup the data before making any changes. Do not delete backup data after changing data until observation period (usually one week) expires and be sure that the equipment is running normally.

Equipment Room Environment

Maintain normal temperature/humidity in the equipment room. Keep the environment tidy and clean, free from dust and moisture. Keep rodents or insects out of the equipment room.

Ensure that primary power of the system is stable and reliable, and check system grounding and lightning protection ground periodically. Check lightning protection system to make sure all facilities are in good condition, especially before storm seasons and after thunderstorms.

The equipment room must have sufficient luminance compliant with relevant standards. Repair lamps damaged in time and make sure that light reaches all around the equipment room.



Tools and Instruments/Meters

All common-use tools, instruments and meters must be available.

Instruments and meters must be subject to periodic checking and calibration to ensure function availability and accuracy.

Spare Materials and Parts

Check spare materials and parts regularly to ensure sufficient stocks and to prevent them from mold.

Store spare materials and parts and faulty ones separately. Mark them properly for easy identification.

Technical Documents

Store maintenance-related application software and technical documents by category at a specified location for easy access when necessary.

Technical Support

Handle faults immediately when they occur. Contact local office of ZTE Corporation for any faults you cannot solve.

Display contact information of local office of ZTE at a conspicuous location in the equipment room. Make it known to all maintenance management personnel, and update it regularly.


C h a p t e r 2

Routine Maintenance

This chapter introduces basic contents for routine maintenance of the ZXWR B09 and lists daily, weekly, monthly and semiannual routine maintenance items.

Overview Routine maintenance refers to periodic preventive maintenance and check on the equipment so that the equipment can run in a stable state for long. Routine maintenance includes:

1. Periodic maintenance check: Make routine check and test the BTS equipment running, required functions, important performance indices and hardware in compliance with prescribed operation steps and methods through various designated background operations or with necessary instruments and meters on regular and scheduled basis.

2. Periodic check: Check hardware parts of BTS equipment and its attached equipment one by one. Adjust, correct or replace any defective part promptly to ensure equipment hardware is in good condition. Regularly maintain and clean components with high dust-proof requirements. Clean important components of other peripherals regularly for normal running.

Caution

Not all routine maintenance items described apply to all kinds of possible cases. It is acceptable to refer to them and work out routine maintenance items according to actual situation.

RNC (Radio Network Controller), in WCDMA system, controls all radio parameters, so following maintenance items do not include network quality analysis and statistics.



Daily Routine Maintenance Items Table 1 shows daily routine maintenance items of the ZXWR B09.

T AB L E 1 D AI L Y R O U T I N E M AI N T E N AN C E I T E M S

Item Sub-item Contents Remar

ks

Alarms and notifications check

Alarm message handling

Check all alarms at the NM terminal, and handle them according to alarm level

Notification message handling

Analyze notification messages that frequently occur and it is acceptable to ignore common ones

Troubleshooting

Troubleshooting

Handle common faults such as transmission fault and board fault

Handle faults reflected by the users

Analyze and handle network quality problem reflected by the user

Weekly Routine Maintenance Items Table 2 shows weekly routine maintenance items of ZXWR B09.

T AB L E 2 W E E K L Y RO U TI N E M AI N TE N AN C E I T E M S

Item Sub-item Contents Remarks

NM

Data backup Backup configuration data for OMCB NMS

Perform system backup at low-traffic

Check and update operating system, anti-virus software and firewall software

Install a patch for operation system of OMCB system

Update virus library and check firewall record

Update operating system immediately when there is a key update for it

Disk capacity check

Check whether disk space satisfies system running requirements

Chapter 2 Routine Maintenance


Monthly Routine Maintenance Items Table 3 shows monthly routine maintenance items of ZXWR B09.

T AB L E 3 M O N T H L Y RO U TI N E M AI N T E N AN C E I TE M S


Radio parameters

Engineering parameters

Check BTS location parameters

Check antenna parameters

Update parameters according to project situation. Save parameters for at least two years

NM

Hardware check

Check whether host and peripherals are in good condition

Check whether network communication is normal

Software check

Check whether operating system is running normally

Checking whether NMS process is normal

Check whether database system is running normally

Data backup

Complete backup log files

Complete backup data files

Backup the files every time before system upgrade, patching or network structure adjustment

BTS equipment

Check BTS equipment and its accessories

Clean the equipment rack

Clean the air filter

Check the cable tree

Check DDF, E1/fiber and all connectors

Check BTS equipment




indicators

Equipment room environment

Temperature and humidity

Check temperature in the equipment room

Check humidity in the equipment room

Spare materials and parts

Spare parts check

Check spare parts for boards

Check spare parts for racks

Check other spare parts

Semiannual Routine Maintenance Items Table 4 shows semiannual routine maintenance items of the ZXWR B09.

T AB L E 4 SE M I AN N U AL RO U T I N E M AI N T E N AN C E I T E M S


Lightning grounding

Lightning grounding

Check working ground of the equipment

Check protection ground of the equipment room

Check grounding trunk line of BTS

Check lightning grounding of the building

Test each type of grounding resistance

Check all items before and after a natural disaster

Antenna feeder system

Iron tower

Check tower light

Check structure and foundation for any distortion or sinking

Check uprightness and height of the tower

Check all types of bolts

Check anticorrosion and rustproof measures

Check all items comprehensively when meeting gale force above 8, earthquake or other natural disaster




Pole

Check installation of fixing parts

Check stress on the pole, pull wire of pull wire tower and ground anchor

Check anticorrosion and rustproof measures

Check uprightness of the pole

Antenna

Check antenna installation parameters

Check fixing status of the antenna

Check pitch angle of the antenna

Feeder

Check installation of feeder and jumper

Check feeder connectors

Check waterproof and airproof measures for antenna feeder system

Check grounding status for feeder

Check water-dropping bend

Other Recommended Maintenance Items Daily Routine Maintenance Items and Semiannual Routine Maintenance Items list maintenance items closely related to the ZXWR B09. There are still other maintenance items that affect the running of the network in daily operations. Refer to Table 5 for examples and recommended maintenance periods.

T AB L E 5 EX AM P L E S O F O T H E R M AI N T E N AN C E I T E M S

Item Sub-item Contents Recommended

Period

BTS equipment

Standing wave ratio test

Test standing wave ratio of each cell

Semiannual




Period

Equipment room environment

Cleanness

Clean the floor, doors, windows, cabinets and other parts

Monthly

Lighting

Check routine lighting and emergency lighting facilities

Sockets

Check whether AC sockets are complete and in good condition

Safety

Check to find out hidden safety troubles

Check fire-control facilities

Check protection measures for the equipment

Devices in the equipment room

Air conditioner

Clean outdoor machine

Clean the air filter

Check all alarm messages

Check installation of air conditioners

Check drainages of air conditioners

Measure input voltage and current

Semiannual

Environment monitoring system

Check running status of each type of sensor

Check the power display.

Check the battery display.

Clean chassis of monitoring system

Monthly

Low-voltage power distribution and switch power supply

Check whether switch and connector are in good condition

Check whether signal indicator and alarm are normal

Clean power distribution device

Check AC feeder

Monthly




Period

and connection parts

Measure temperature rise of the fuser

Battery

Clean batteries

Measure voltage of a single battery

Measure end voltage of each battery and ambient temperature

Check whether there is any liquid leakage

Check whether contact of leading wire and terminal are well and whether there is erosion

Check whether connection pieces between batteries are tight

Quarterly

Capacity discharging test

Yearly

Diesel generator

Charge startup battery, and add distilled water when necessary

Semimonthly

Clean the equipment

Check startup, cooling, lubricating and fuel systems

Run the machine for 20 minutes, without any load

Monthly


C h a p t e r 3

Notification and Handling

This chapter introduces types of notification messages that may occur during running of the ZXWR B09, and gives possible causes of them.

Notification Messages When any unrepeatable or transient abnormality occurs during the running of ZXWR B09, the system reports in the form of notification. Maintenance management personnel learn running status of each part of Node B from notification message.

Board Notification

SSCOP Error

Item Contents

Description SSCOP error

Alarm level Alarm notification

Alarm type Communication alarm

Cause SSCOP receives error PDU

ALCAP Link Error

Item Contents

Description ALCAP link error




Item Contents

Alarm type Error handling alarm

Cause ALCAP receives invalid message or the status is error

AAL5_MAC Error

Item Contents

Description AAL5_MAC error



Cause Packet loss or error packet occurs on this link, or the switching network is error

RS232 Serial Port Error

Item Contents

Description RS232 serial port error

Alarm level Notification


Cause

1. GPS RS232 serial port receiving frame CRC error;

2. GPS RS232 serial port sending data error;

3. Micro-Control Unit (MCU) RS232 serial port receiving frame CRC error;

4. Micro-Control Unit (MCU) RS232 serial port sending data error.

STM-1 B1 Error Code

Item Contents

Description STM-1 B1 error code alarm



Cause

Quality of transmission line is deteriorated (optical power is too big or too small); there is strong electromagnetic interference near the optical interface; optical connector is not clean; ambient temperature where the equipment works is too high.

Chapter 3 Notification and Handling


STM-1 B2 Error Code

Item Contents




Cause


STM-1 Remote B2 Error Code Indication

Item Contents

Description STM-1 remote B2 error code indication alarm



Cause This alarm is the reply alarm when peer end detects received B2 error codes.

Examples of Other Maintenance Items STM-1 B3 Error Code

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Cause




STM-1 B3 Remote Error Code Indication

Item Contents

Description STM-1 B3 remote error code indication alarm



Cause This alarm is the reply alarm when peer end detects received B2 bit error.

STM-1 Multiplex Section Remote Defect Indication (MSRDI)

Item Contents

Description STM-1 Multiplex Section Remote Defect Indication (MSRDI)



Cause Peer end returns MSRDI alarm to this end when receiving LOS, LOF or MSAIS alarm.

STM-1 Higher-order Path Defect Indication (HPRDI)

Item Contents

Description STM-1 Higher-order Path Defect Indication (HPRDI)



Cause Remote end returns HPRDI alarm to this end when receiving HP-AIS, AU-LOP or path tracing byte mismatching message.

Chapter 3 Notification and Handling


STM-1 Higher-order Path Lady Type Mismatching (HPPLM)

Item Contents

Description STM-1 Higher-order Path Lady Type Mismatching (HPPLM)



Cause Load type (C2 byte) borne by higher-order path in STM-1 frame structure received by this end is not ATM. This alarm occurs along with other alarms.

Loss of STM-1 Cell Delimitation (LCD)

Item Contents

Description Loss of Cell Delimitation (LCD) of STM-1



Cause The clock is not synchronized or there is a bit error. Other STM-1 alarms occur at the same time usually.

STM-1 Received Cell with CRC Error

Item Contents

Description STM-1 received cell with CRC error



Cause The clock is not synchronized or there are error codes. Other STM-1 alarms occur at the same time generally.

E1 Link HDB3 Coding Violation

Item Contents



Item Contents

Description E1 link HDB3 coding violates the rule



Cause IIA board interface performance; E1 cable quality is poor; equipment shares the ground.

E1 Link Slip

Item Contents

Description E1 link slip alarm



Cause The E1 clock is out of synchronization.

Too-Heavy ATM Traffic

Item Contents

Description ATM traffic is too heavy.



Cause Actual traffic of ATM exceeds the preset bandwidth.


C h a p t e r 4

Alarm and Handling

This chapter introduces types of alarm messages that may occur during running of the ZXWR B09, and gives severities (levels), possible causes and troubleshooting methods.

Alarm Messages Any problem or fault that occurs during running of the ZXWR B09 is reported in form of an alarm message.

Usually, alarm messages last some time and do not disappear until corresponding problems or faults disappear.

Alarm messages fall into four levels, level 1: Critical, level 2: Major, level 3: Minor and level 4: Alarming.

1. Critical alarm

It is an alarm for board failure.

For example: related resources of a board are blocked, functions of the system are fatally affected, and maintenance and management personnel need to replace the board or perform other troubleshooting procedures to clear the fault.

2. Major alarm

It is an alarm for a serious fault, and it will last for some time.

Functions of the system are seriously affected, with signs of services being affected. For example, QoS of a type of equipment severely degrades, and maintenance and management personnel need to perform emergency repair to eliminate the fault.

3. Minor alarm

It is an alarm for a minor fault.

Functions of the system are slightly affected, indicating existence of factors that do not affect normal services. It is necessary to take measures to prevent severe faults and to



let maintenance and management personnel eliminate the fault.

4. Alarming alarm

It is an alarm that indicates existence of potential problems or problems that are about to affect normal services. It is necessary to take measures to prevent them from developing into faults that may severely affect normal services.

Following sections details possible alarms in the system for users reference. Contact Customer Support Center of ZTE in time if failing to handle a generated alarm.

CCS Alarms Note

When handling with alarms, perform in the order of Handling until alarm vanish. For example, if there are 5 steps in Handling and alarms vanish when you go on with Step 3, Seps 4 and 5 are unnecessary.

SSCOP Signaling Link Disconnected

Item Contents

Description SSCOP signaling link is disconnected.

Alarm level Major alarm


Cause

1. Transmission layer parameters are not configured consistent for Node B, RNC and cascaded Node B;

2. Node B transmission layer error;

3. Communication cable error;

4. Peer RNC or cascaded Node B fails.

Handling

1. Check whether transmission layer parameters are configured consistent for Node B, RNC and cascaded Node B. Modify configurations if not consistent;

2. Reset IIA or CCS;

3. Check whether communication cable gets faulty;

4. Check whether peer RNC or cascaded Node B fails.

Chapter 4 Alarm and Handling


Clock Reference Source Lost

Item Contents

Description Clock reference source lost

Alarm level Alarming alarm

Alarm type Equipment alarm

Cause

1. IIA1 clock reference source lost;

2. IIA2 clock reference source lost;

3. GPS clock lost;

4. BITS clock lost,

Handling

If it is the line clock reference source lost, check whether the system configures the line clock reference source by mistake;

If it is GPS 1pps reference source lost:

1. Check whether there are alarms with GPS. Handle with them if there are any;

2. Check whether connection between EMC and CCS is normal;

3. Replace GPS.

If it is 8 kHz clock reference source lost:

1. Check whether connection between EMU and CCS is normal;

2. Check the external clock.

Clock Module Error

Item Contents

Description Clock module error

Alarm level Critical alarm


Cause

1. 61.44 M clock alarm;

2. 10 M clock alarm;

3. FR alarm;

4. FN alarm.

Handling

1. Check whether system clock signal are abnormal;

2. Check whether there are clock signals input on boards;

3. Check whether connection between boards and backplane is abnormal;

4. Check whether board clock receiving module is abnormal.



Board Communication Link Disconnected

Item Contents

Description Board communication link is disconnected.



Cause 1. Communication cables error;

2. Board error.

Handling

1. Configuration board must be inserted in the slot. If it is the middle transfer board error, unplug the middle link disconnected board first;

2. Unplug the link disconnected board;

3. Replace the link disconnected board or middle transfer board.

Active/Standby Synchronization Failure

Item Contents

Description Active/Standby synchronization failure

Alarm level Minor alarm


Cause

1. Database active/standby synchronization failure;

2. Operation software version synchronization failure;

3. Backup software version synchronization failure.

Handling

1. Confirm whether there are active/standby link disconnected alarm;

2. Confirm there are version error alarms on MS board and hardware error on backup board;

3. Not intervene, waiting for the system to restore automatically;

4. Reset the board if the system fails to restore automatically;

5. Replace CCS backplane.



Software Version Error

Item Contents

Description Software version error



Cause There are correlated records of this software on the foreground or the file of this type software saved on the foreground is damaged.

Handling Re-download faulty software version.

Software Operation Failure

Item Contents

Description Software operation failure



Cause Software version error or board error

Handling

1. Check whether software version alarm exits;

2. Reset the board;

3. Replace the board.

Board Parameter Synchronization Abnormal

Item Contents

Description Board parameter synchronization abnormal



Cause

1. Board is configured but not plugged;

2. Board link is disconnected;

3. Board software is abnormal.

Handling

1. Check whether there are board link alarms. If so, handle with the alarm and repeat the configuration process or restart the board;

2. Check whether there are board application software monitoring alarms. If so, handle with the alarm and reset the board;

3. Re-configure parameters on the background;



Item Contents

4. Re-start the board.

Application Software Monitoring Alarm

Item Contents

Description Application software monitoring alarm



Cause 1. Communication line error;

2. Board error.

Handling

1. Check whether there are board link alarms;

2. Reset;

3. Replace the board with alarms.

Database Save Failure

Item Contents

Description Database save failure



Cause 1. Harddisk error;

2. Harddisk is full.

Handling Replace the board.

Reference Resource PRI Configuration Failure

Item Contents

Description Reference resource PRI configuration failure



Cause The system configures the reference source that is not supported.

Handling Check whether the system has configured the reference source that is not supported. If so,



Item Contents

delete it and reset the board and the switching.

SSCOP Delivery Buffer Overflow

Item Contents

Description SSCOP delivery buffer overflow



Cause The message is abnormal.

Handling Reset the CCS.

Board Configuration Error Alarm

Item Contents

Description Board configuration error alarm



Cause

1. The board on the left RBI slot is configured error;

2. The board on the right RBI slot is configured error;

3. The board on the BP slot is configured error.

Handling Modify the background configurations.

SNTP Time Alignment Failure Alarm

Item Contents

Description SNTP time alignment failure alarm



Cause 1. IP address of SNTP server is configured faulty;

2. Link with SNTP server error.

Handling

1. Check whether the link with SNTP server is error;

2. Check whether the IP address of SNTP server is configured faulty.



Clock Reference Source Deterioration

Item Contents

Description Clock reference source deterioration



Cause The reference clock quality is too bad.

Handling

1. If current reference source is a line clock, inform RNC-related personnel of normal clock input;

2. Replace the reference source.

CPU Overload Alarm

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Description Board configuration error alarm



Cause High-layer software operation abnormal or board error, which results in frequent alarm reports.

Handling Check whether there are alarms on the board and isolate the faulty board.

Board Hardware Error

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Description Board hardware error



Cause Equipment hardware is abnormal.

Handling Replace the error board.



RBI Alarms

Clock Module Alarm

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Description RBI clock module alarm



Cause

1. System clock signal is abnormal;

2. Connection between board and backplane is abnormal;

3. Board clock receiving module gets abnormal.

Handling

1. Check whether CCS has a clock alarm. Solve it first if such a clock alarm exists;

2. Reset the RBI;

3. Unplug and plug the RBI;

4. Replace the RBI.

Downlink LVDS Link Error

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Description Downlink LVDS link error



Cause

1. LVDS transmitting module of upstream board is abnormal;

2. LVDS link of corresponding backplane is abnormal;

3. Interface between board and backplane is abnormal;

4. LVDS receiving module gets abnormal.

Handling

1. Make sure corresponding board and backplane are in good contact;

2. Reset the RBI;

3. Reset upstream boards (BP and TRXU);

4. Replace the RBI;

5. Replace upstream boards.



Uplink LVDS Link Error

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Description Uplink LVDS link error



Cause

1. LVDS transmitting module of corresponding TRXU is abnormal;



4. LVDS receiving module gets abnormal.

Handling

1. Make sure corresponding board and backplane are in good contact;

2. Reset the RBI;

3. Reset corresponding TRXU;

4. Replace the RBI;

5. Replace corresponding TRXU.


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Handling

1. Check whether there are software version alarm;

2. Reset the board;


Board Configuration Parameter Error

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Description Board configuration parameter error



Cause Configuration parameter error or hardware error



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Handling 1. Reset the board;


CPU Overload Alarm

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Description CPU overload alarm




Handling Observe whether there are alarms on the board and isolate the faulty board.

Remote Clock Reference Alarm

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Description Remote clock reference alarm



Cause

1. System clock signals are abnormal;

2. Connection between the board and the backplane is abnormal;

3. Board clock receiving module is abnormal.

Handling

1. Check whether there are clock type alarms on the CCS. If so, handle with it first;

2. Reset the RBI;

3. Unplug the RBI;

4. Replace RBI.


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Optical Module Not-in-position

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Description Optical module is not in position.



Cause Corresponding optical module is not in position or abnormal.

Handling Check whether the corresponding optical module is in position. If so, replace the corresponding optical module.

Optical Module Receiving Failure

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Description Optical module receiving failure



Cause

1. The corresponding RF remote is abnormal;

2. Fibers on corresponding optical interface are abnormal;

3. Connection of optical interface that the board corresponds to is abnormal;

4. Optical module that the board corresponds to is abnormal.

Handling

1. Confirm that the connection of the corresponding optical interface is well;

2. Self-loop corresponding optical interface. If the alarm still exists, go on with Step 3. If the alarm disappears, it proves that it is the fiber or corresponding RF remote error. Check the fibers. If the fibers are normal, go on with Step 6;

3. Reset the RBI;

4. Replace RBI alarm optical module;

5. Replace the RBI;

6. If conditions permit, check whether corresponding RF remote is normal.



IIA Alarms

Loss Of Signal (LOS) of STM-1

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Description Loss Of Signal (LOS) of STM-1



Cause

The fiber is not corrected or connected with inverse receiving and transmitting; the fiber is disconnected; local optical module is damaged; peer end does not send optical interface.

Handling

1. Connect the fiber with Node B if not already connected. Exchange receiving and transmitting fibers if the alarm still exists;

2. Make self-loop for Node-B optical interface with a fiber. Replace optical module of IIA or replace IIA if the alarm still exists. Node B is OK if the alarm disappears. Go on with Step 3;

3. Check status of RNC or optical transmission equipment connecting Node B. Loop back with fiber level by level to locate the fault.

Loss Of Frame (LOF) of STM-1

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Description Loss Of Frame (LOF) of STM-1



Cause The clock is not synchronized.

Handling

1. Check CCS alarm status. Eliminate clock alarm first if it exists;

2. Check whether clock status of RNC or transmission equipment is normal.

Multiplex Section Alarm Indication of STM-1 (MSAIS)

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Description Multiplex Section Alarm Indication of STM-1 (MSAIS)



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Cause

MS-AIS alarm is sent to downstream equipment when LOS and LOF alarms occur to upstream equipment of Node B. It is also possible that NMS inserts an MSAIS alarm in transmission equipment.

Handling Check alarm status of upstream equipment of Node B and eliminate the alarm.

Loss Of Pointer (LOP) of STM-1 AU4

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Description Loss Of Pointer (LOP) of STM-1 AU4



Cause Unsynchronized clock of transmission equipment results in pointer adjustment.

Handling

1. Check whether CCS has a clock alarm;

2. Check whether RNC or transmission equipment has a clock alarm.

Loss Of Electrical Signal (LOS) of E1 Link

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Description Loss Of electrical Signal (LOS) of E1 Link



Cause

E1 line is not connected or connected with inverse receiving and transmitting; E1 cable is disconnected; local E1 receiving module or peer E1 transmitting module is damaged.

Handling

1. Check whether E1 line of the alarm link is connected properly or connected with inverse receiving and transmitting;

2. Make self-loop for the alarm link with E1 line. Node B is OK if the alarm disappears. Check whether peer equipment is normal;

3. Insert IIA to another slot, and make self-loop with E1 line. E1 cable or E1 transfer board fails and must be



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replaced if the alarm disappears and replace IIA if the alarm still exists.

Loss Of Frame (LOF) Synchronization of E1 Link

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Description Loss Of Frame (LOF) synchronization of E1 Link



Cause The clock is out of synchronization.

Handling

1. Check whether there are Loss of electric Signal (LOS) alarm on IIA;

2. Check whether there are lock alarms on the IIA;

3. Check the alarm status of CCS;

4. Reset the IIA;

5. Check whether the clock status of RNC or transmission equipment is normal.

Loss of Cell Delimitation (LCD) of E1 Link

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Description Loss of Cell Delimitation (LCD) of E1 link



Cause

1. The clock is out of synchronization;

2. The TC layer parameters for IMA connecting both parties are inconsistent.

Handling

1. Check the TC layer parameters for IMA connecting both parties. Modify them consistent if they are inconsistent;

2. Check whether the RNC has a clock alarm.

Loss of IMA Frame (LIF) of E1 Link

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Description Loss of IMA Frame (LIF) of E1 link



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Cause

1. The scrambling/descrambling parameters for IMA connecting dual-transmitting are set inconsistent;

2. The clock is out of synchronization.

Handling

1. Check scrambling/descrambling parameters for IMA connecting dual-transmitting. Modify them consistent if they are inconsistent;

2. Check whether the CCS has a clock alarm;

3. Check whether RNC has a clock alarm.

E1 IMA Group in Non-Working Status

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Description The E1 IMA group is not in a working status.



Cause

This alarm indicates E1 link in IMA group gets faulty, and IMA group is not in a working state, unable to receive/send data. All above E1 alarms may result in this alarm.

Handling

1. Make self-loop for E1 link in IMA group at Node-B side. Node B fails if the alarm still exists. Solve the problem step by step by with the method for solving other E1 alarms. Go on with Step 2 if the alarm disappears

2. Check whether both parties IMA settings (IMA version, scrambling/descrambling or not and frame length) are consistent. Modify them if they are inconsistent. Set IMA clock mode of Node B as ITC if doubting the clock fails. The clock is error and check clock boards of the peer end and local end if the alarm disappears. Make loop-back level by level to locate the section where the problem occurs if doubting E1 connection line fails.

PVC Error

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Description PVC error




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Cause ATM link error

Handling

Perform the link self-loop. If the alarm disappears, it indicates that Node B is normal. Check the opposite equipment. If the alarm still exists, replace the board.

Transmission Clock Abnormal

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Description Transmission clock abnormal



Cause The board is not inserted tight. CCS clock unit error. Board error. Backplane error, etc.

Handling

1. Check whether there are clock type alarm on CCS;

2. Unplug and plug the IIA;

3. Replace the IIA.


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Handling


2. Reset the board;



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Configuring IMA Group Failure

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Description Configuring IMA group failure



Cause Iub port already exists or parameter error

Handling

1. Confirm that parameter configurations are correct;

2. Delete this IMA group and configure again;

3. Reset the board;


Configuring STM-1 Port Failure

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Description Configuring STM-1 port failure



Cause Iub port already exists or parameter error

Handling


2. Delete this IMA group and configure again;

3. Reset the board;


Configuring TC Port Failure

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Description Configuring TC port failure



Cause Parameter error



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Handling


2. Delete this TC group and configure again;

3. Reset the board;


Configuring PVC Failure

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Description Configuring PVC failure



Cause 1. Parameter error;

2. Hardware error.

Handling


2. Delete this PVC and configure again;

3. Reset the board;


CPU Overload Alarm

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Cause Equipment hardware error



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Handling Replace the error board

Optical Module Not-in-position

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Description Optical module is not in position.



Cause Corresponding optical module is not in position or abnormal.

Handling Check whether the corresponding optical module is in position. If so, replace the corresponding optical module.

TAC Alarms


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Handling


2. Reset the board;



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Board Hardware Local Channel Error

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Description Board hardware local channel error



Cause Error of tower amplifier that TA corresponds to

Handling Replace the tower amplifier


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EMU Alarms

Ambient Temperature Abnormal

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Description Ambient temperature is abnormal.


Alarm type Ambient alarm

Cause

1. The temperature is too high or too low (out of the temperature range that the system configures);

2. EMU board error



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Handling

1. Check whether the threshold of configuration parameters is too high or too low;

2. Check whether the ambient temperature is too high (low) with the thermometer;

3. Reset the EMU;

4. Replace the temperature sensor;

5. Replace the EMU.

Whole Equipment Temperature Rise Alarm

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Description Whole equipment temperature rise alarm


Alarm type Ambient alarm

Cause

Temperature difference at EMU intake and outtake detected by EMU is over 15 C. Possible causes

are:

1. Dust-proof net is blocked;

2. Fan error;

3. Temperature sensor error;

4. EMU board error.

Handling

1. Check whether there are alarms on fans;

2. Check whether the dust-proof net on racks are blocked;

3. Replace the two temperature sensors of set-top fans;

4. Reset the EMU;

5. Replace the EMU.

Clock Reference Source Loss

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Description Clock reference source loss



Cause 1. EMU 2 MHz loss;

2. EMU 2 Mbps loss.

Handling 1. Check whether the clock reference source is configured;

2. Check whether there are external BITS. If so,



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check whether the BITS has clock output signals and whether it is normal;

3. Check whether the connection between BITS and EMU is correct.

Rack Power Abnormal

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Description Rack power abnormal



Cause

1. 48 V over-voltage (over 57 V 1 V);

2. 48 V under-voltage (below 40 V 1 V);

3. EMU board error;

4. Lightening arrester error.

Handling

1. If it is the voltage alarm, use the multimeter to detect the rack power voltage. If the measured value is over or under voltage, it indicates that something is wrong with the voltage of 48 V power and it needs solution;

2. If it is the lightening arrester alarm, replace it to detect the alarm status. If the alarm disappears, it indicates that the lightening arrester is damaged and it is necessary to replace one;

3. Reset the EMU;

4. Replace the EMU.

Board Communication Link Disconnected

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Description Board communication link disconnected



Cause 1. Communication cable error;

2. Board error.

Handling

1. The configured board should be inserted in the slot. If it is the middle transit board error, unplug it first;

2. Unplug the link disconnected board;

3. Replace the link disconnected board or middle transit board.




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Handling

1. Check whether there are software version alarms;

2. Reset the board;



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Fan Alarm

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Description Fan alarm



Cause

1. Cable error;

2. Fan error;

3. EMU error.

Handling

1. Check whether there are alarms on the whole layer of fans. If so, check cables of EMU and fans;

2. Replace faulty fans;

3. Reset the EMU;

4. Replace the EMU.



Temperature Sensor Not-in-position

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Description Temperature sensor is not in position.



Cause

1. Cables between EMU and fan layer is error;

2. Temperature sensor connection is error;

3. FCC or FCD error;

4. EMU error.

Handling

1. Check whether connection between the fan board in the layer that faulty temperature sensor locates and EMU is faulty;

2. Open corresponding fan layer to check whether the temperature sensor is connected to FC correctly;

3. Replace the FC board that the faulty temperature sensor corresponds to;

4. Reset EMU;

5. Replace EMU.

Father Node External Equipment Error

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Description Father node external equipment error



Cause

1. External equipment error;

2. Father node connection error;

3. EMU error.

Handling

1. Check whether there are faults with external equipment;

2. Check whether connections between external equipment and father node is normal;

3. Replace the EMU.



CPU Overload Alarm

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Handling Observe whether there are alarms on the board and isolate the error board.


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TRXU Alarms

Clock Module Error

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Cause



3. FR alarm;

4. FN alarm.

Handling

1. Check whether system clock signals are normal;

2. Check whether there are clock signal input on boards;

3. Check whether the connection between the



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board and the back plane is normal;

4. Check whether the board time receiving module is normal.

Downlink LVDS Link Error

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Description Downlink LVDS link error



Cause

1. Upstream board LVDS transmitting module is abnormal;



4. Board LVDS receiving module is abnormal.

Handling

1. Make sure alarm board and backplane are in good contact;

2. Reset the alarm board;

3. Reset the upstream boards (RBI);

4. Replace the alarm board;

5. Replace the upstream boards.


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Handling


2. Reset the board;





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CPU Overload Alarm

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Board Hardware Local Channel Error

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Description Board hardware local channel error



Cause Transmitting or receiving channel error

Handling Replace the tower amplifier


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BP Alarms

Clock Module Error

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Cause



3. FR alarm;

4. FN alarm.

Handling


2. Check whether there are clock signal input on the board;

3. Check whether the connection between the board and the backplane is normal;

4. Check whether the board clock receiving module is normal.

Uplink LVDS Link Error

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Description Uplink LVDS link error



Cause


2. Interface between the board and the backplane is abnormal;

3. Board LVDS receiving module is abnormal.

Handling 1. Determine whether the board and the backplane is well connected;



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2. Reset the RBI;

3. Reset the corresponding TRXU;

4. Replace the RBI;

5. Replace the corresponding TRXU.

Uplink Path Operation Abnormal

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Description Uplink path operation is abnormal.



Cause 1. Internal communication error;

2. Hardware error.

Handling 1. Reset or unplug the board;

2. Replace the BP.

Downlink Path Operation Abnormal

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Description Downlink path operation is abnormal.



Cause BP high-layer software and DSP communication error

Handling 1. Reset or unplug the board;

2. Replace the BP.


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Handling


2. Reset the board;



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CPU Overload Alarm

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Signal Receiving Path Quality Abnormal Alarm

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Description Signal receiving path quality abnormal alarm



Cause Receiving path error

Handling Check whether the RF cable interface (including antenna interface) of corresponding path is loose.

RDM Alarms

Clock Module Error

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Cause



3. FR alarm;

4. FN alarm.

Handling


2. Check whether there are clock signal input on the board;

3. Check whether the connection between the board and the backplane is normal;

4. Check whether the board clock receiving module is normal.

Antenna VSWR Exceeding 3.0

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Description The antenna VSWR (Voltage Standing Wave Ratio) exceeds 3.0.




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Cause The backplane and RF cable are not in good contact.

Handling

1. Unplug and plug RDM board to make sure it is in good contact with the backplane;

2. Check to make sure antenna at DDL antenna interface is screwed tight;

3. Check to confirm if water enters the antenna;

4. Reset RDM.

Antenna VSWR Exceeding 1.8

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Description The antenna VSWR exceeds 1.8.



Cause The backplane and RF cable are not in good contact.

Handling

1. Unplug and plug RDM to make sure it is in good contact with the backplane;

2. Check to make sure the antenna at the DDL antenna interface is screwed tight;

3. Check to confirm if water enters the antenna;

4. Reset RDM.

Calibration Interface Over-power Alarm

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Description Calibration interface over-power alarm



Cause Power at calibration interface is over 30 dBm.

Handling

1. Check whether there are RF cables connected with DDL antenna interface at RDM calibration interface. If so, go on with Step 2. If not, go on with Step 3;

2. Check whether there are local cells in TRXU connecting DDL RF cables. If so, block this local cell;

3. Reset the RDM.




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Handling

1. Check whether there are software version error;

2. Reset the board;



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Cause Configuration parameter error or board error



CPU Overload Alarm

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LPA30 Alarms


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Link Disconnected between LPA30 and EMC

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Description Link between LPA30 and EMC is disconnected.



Cause 1. Communication cable is error;

2. LPA30 fails.

Handling 1. Unplug and plug the LPA30;

2. Replace the LPA30.

Over-power Alarm

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Description LPA30 over-power alarm




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Cause Possibly signal power of power amplifier LPA30 input port, exceeds maximum output power 2dB.

Handling

1. Enable protected power amplifier;

2. Reset or restart the alarm power amplifier LPA30;

3. Replace the TRXU;


Over-VSWR Alarm: VSWR2.8

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Description LPA30 over-VSWR alarm, VSWR2.8



Cause

Matching of power amplifier LPA30 port may fail (for example, cable output to the duplexer is not in good contact, or duplexer output port is not in good contact with the feeder).

Handling

1. Check whether power amplifier cable output to the duplexer is in good contact, and whether cable connector is screwed tightly;

2. Check whether connectors between duplexer output port and feeder and between antenna and feeder are screwed tightly;

3. Reset the LPA30;


Over-Temperature Alarm

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Description LPA30 over-temperature alarm



Cause Power amplifier layer may fail in heat sinking. For example, fans on the power amplifier layer work abnormally.

Handling

1. Confirm if EMU generates a heat-sinking fan alarm on power amplifier layer;

2. Enable protected LPA30 board and make a recovery attempt;

3. Reset the LPA30;



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Over-Current Alarm

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Description LPA30 over-current alarm



Cause Possibly power amplifier LPA30 fails.

Handling

1. Enable protected LPA30 board and make a recovery attempt;

2. Reset the LPA30;


LPA30 VSWR Alarm, 2.8>VSWR1.8

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Description LPA30 VSWR alarm, 2.8>VSWR1.8



Cause Matching of power amplifier LPA30 port may fail.

Handling

1. Check to make sure that power amplifier cable output to duplexer is in good contact and cable connector is screwed tightly;

2. Check to make sure that connectors between duplexer output port and feeder and between antenna and feeder are screwed tightly.


C h a p t e r 5

Troubleshooting Examples

This chapter introduces some common problems during routine operation and maintenance of the ZXWR B09, and presents symptoms, possible causes and solutions.

Overview Table 6 shows possible problems during routine maintenance of the ZXWR B09.

T AB L E 6 CO M M O N P R O B L E M S I N RO U T I N E M AI N T E N AN C E

Classification Problem Remarks

System monitoring

CPU utilization too high

See High CPU Utilization

Decreased cell radius of BTS coverage

See Decreased Radius of BTS Coverage

User complaint

Difficult call connection

See Difficult Call Connection

Poor call quality See Poor Call Quality

Slow to access Internet

See Slow to Access Internet



System Monitoring

High CPU Utilization

Symptoms and Effects

Alarm man-machine interface of operation and maintenance console has a CPU utilization alarm reported, or CPU utilization exceeds normal value for a long time when monitoring CPU utilization at performance management man-machine interface.

High CPU utilization is of great concern. Processing capability of the system decreases if CPU of CCS is at a high utilization for a long time. It results in sharp rise of call loss and may cause memory exhaustion or system breakdown.

Causes

Rise of CPU utilization of a board (particularly CCS board) may result from:

1. The system is busy currently, for example, high traffic.

2. Too many measurement tasks are set, and there are more measurement report messages.

3. The system has a local emergency fault, causing a large number of alarm messages reported

Handling

Analyze the cause and take appropriate measures in case of high CPU utilization ratio for a long time.

1. Locate the fault and isolate it by blocking failed board and parts or using other methods if there is a large amount of burst alarm reports.

2. Adjust measurement strategy properly if there are too many measurement message reported, for example, cancel some less important measurement tasks or change the period when performing measurement tasks.

Chapter 5 Troubleshooting Examples


Decreased Radius of BTS Coverage


Conversation quality at the edge of cell decreases, and measurement with instruments shows that coverage radius of BTS signals decreases.

Causes

1. Some radio parameters are set improperly, particularly pilot channel transmitting power and forward transmitting power, which affects actual coverage of BTS.

2. Surrounding landform and geographical feature changes, for example, urban construction, also affect actual coverage.

3. Interference in space electromagnetic environment causes pilot pollution.

4. Antenna feeder system gets faulty.

Handling

Conduct an on-site survey and detailed spectrum test near the site, and configure radio parameters again based on ambient characteristics and test result. It is better to let professional network optimization personnel perform this task.

User Complaints

Difficult Call Connection


Users complain that call completion rate (successfully connected to called party) decreases significantly and calls cannot be connected at all in extreme cases.



Causes

Call completion rate is a basic index to evaluate overall performance of the system. A great variety of factors may affect it, inclu