RET Antenna TD-LTE Maintenance Guide(01)

RET Antenna

TD-LTE Maintenance Guide

Issue

01

Date

2013-08-29

Huawei Technologies Co., Ltd. -

Copyright © Huawei Technologies Co., Ltd. 2013. All rights reserved. No part of this document may be reproduced or transmitted in any form or by any means without prior written consent of Huawei Technologies Co., Ltd.

Trademarks and Permissions and other Huawei trademarks are trademarks of Huawei Technologies Co., Ltd. All other trademarks or registered trademarks mentioned in this document are the property of their respective holders.

Notice The purchased products, services, and features are stipulated by the commercial contract made between Huawei and the customer. All or partial products, services, and features described in this document may not be within the purchased scope or the usage scope. Unless otherwise agreed by the contract, all statements, information, and recommendations in this document are provided "AS IS" without warranties, guarantees or representations of any kind, either express or implied. The information in this document is subject to change without notice. Every effort has been made in the preparation of this document to ensure the accuracy of the contents, but all statements, information, and recommendations in this document do not constitute the warranty of any kind, express or implied.

Huawei Technologies Co., Ltd. Address:

Huawei Industrial Base Bantian, Longgang Shenzhen 518129 People's Republic of China

Website:

http://www.huawei.com

Email:

[email protected]

Telephone:

0086-755-28560000 0086-4008302118

Fax:

0086-755-28560111

Issue 01 (2013-08-29)

Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd

ii

RET Antenna TD-LTE Maintenance Guide

About This Document

About This Document Overview This document describes the symptoms, causes, and troubleshooting methods of common faults of Huawei remote electrical tilt (RET) antennas, including the antenna information management module (AIMM). It aims to help field engineers rectify faults or check whether faults are caused by the AIMM. This version can be used only for LTE TDD eNodeBs.

Intended Audience This document is intended for: 

Technical support engineers



Maintenance engineers

Change History 01 (2013-08-29) It is the initial release.

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Contents

Contents 1 General Safety Information ........................................................................................................ 1 2 Maintenance Preparations ........................................................................................................... 3 3 Maintenance ................................................................................................................................... 4 3.1 RET Antenna Configuration Query .................................................................................................................. 4 3.2 Non-Alarm Maintenance .................................................................................................................................. 4 3.2.1 No AIMM Scanned or Partial AIMMs Scanned ..................................................................................... 4 3.2.2 ALD Link Disconnection After Addition of the ALD ............................................................................. 6 3.2.3 The Scanned SNs is not the antenna SNs,but the AIMM SNs ................................................................ 7 3.3 Alarm Maintenance .......................................................................................................................................... 8 3.3.1 RET Communication Abnormal ............................................................................................................. 8 3.3.2 RET Motor Abnormal ........................................................................................................................... 10 3.3.3 RET Not Calibrated .............................................................................................................................. 12 3.3.4 RET Data Loss ...................................................................................................................................... 14 3.3.5 RET Data Abnormal.............................................................................................................................. 15 3.3.6 ALD Hardware Fault............................................................................................................................. 17 3.4 Equipment Replacement ................................................................................................................................ 18

A Appendix ..................................................................................................................................... 20 Acronyms and Abbreviations ............................................................................................................................... 20

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1 General Safety Information

1

General Safety Information

The precautions described in this chapter should be followed when you select the measuring and testing equipment for installing, operating and maintaining Huawei products and equipment.

Safety Precautions For the safety of personnel and equipment, comply with the symbols on the equipment and the safety instructions in this document when installing, operating, and maintaining Huawei products and equipment. Indications such as Danger, Caution, and Note serve only as the supplementary information of general safety precautions.

Local Regulations and Standards Comply with local safety regulations during the operations. Safety precautions described in this document are only supplementary to local safety regulations.

General Requirements for Installation Before installing and maintaining Huawei products, the associated engineers should undergo trainings and learn about proper operation methods and safety precautions. 

Only the qualified engineers are allowed to install, operate, and maintain Huawei products and equipment.



Only the qualified engineers can remove safety equipment and maintain the equipment.



Equipment or components (including software) should be replaced or changed by the personnel certified or authorized by Huawei.



The operators should timely report the faults or errors that may endanger the safety of the personnel in charge.

Grounding Requirements The following requirements are specific for the equipment for which grounding is required: 

Never install the equipment before it is properly grounded. Never disconnect the ground cable before the equipment is removed.



Never damage the ground conductor.

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1 General Safety Information



Never operate the equipment before the ground conductor is installed.



The equipment must be grounded permanently. Before operating the equipment, check the electrical connection of the equipment and ensure that the equipment is securely grounded.

Personnel Safety 

Never operate the equipment or touch the cables in the case of a thunderstorm.



Remove the AC power connector in the case of a thunderstorm. Do not use the fixed terminal, or touch the terminal or the antenna connector in such weather conditions.



To avoid electric shocks, never connect the safety extra-low voltage (SELV) ciAIMMit to the telecommunication network voltage (TNV) ciAIMMit.



Never look at the optical port directly with eyes to prevent laser from injuring your eyes.



Before operating the equipment, wear electrostatic discharge (ESD) clothes, ESD gloves, and ESD wrist strap. Remove conductive objects such as jewelry and watches to avoid electric shocks or burns.



In the case of fire, immediately leave the building or the equipment room. Turn on the fire alarm bell or make an emergency call. Never enter the building on fire.

Equipment Safety 

Before the operation, ensure that the equipment is firmly anchored to the floor or other solid objects, such as a wall or an installation rack.



Never block the RET antenna’s drainage hole.



When installing an AIMM, use tools to tighten screws.



After the installation, remove the packing materials from the equipment area.

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2 Maintenance Preparations

2

Maintenance Preparations

Before maintaining the RET antenna, maintenance engineers need to learn about sites and prepare maintenance tools. Before configuring and maintaining the RET antenna, maintenance engineers or technical support engineers need to prepare the tools as listed in Table 2-1. Table 2-1 List of maintenance tools Tool

Exterior

Function

Gloves

It is used to protect the hands from injuries.

Safety belt

It is used to protect the safety of the personnel working on the tower platform.

Phillips screwdriver

It is used to fasten or loosen screws.

(M3–M6)

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3 Maintenance

3

Maintenance

3.1 RET Antenna Configuration Query During the maintenance process, you can check the configuration of the RET, including power supply configuration, device information query and configuration, and device function query and configuration. You can configure the RET antenna through the M2000 or LMT. For details about how to configure the RET antenna, see the RET Antenna TD-LTE Configuration Guide.

Power Supply Configuration Information Query According to actual application scenarios, run the LST ANTENNAPORT and DSP ANTENNAPORT command(OOK mode) or LST RETPORT and DSP RETPORT command (RS485 mode) (about the mode description please see the see the RET Antenna TDLTE Configuration Guide.) to command to get the current configuration and also check whether the current consumption is right.

Device Information Query Run the LST RET command to query the configuration of the AIMM connected to the system. Run the DSP ALDVER command to check the AIMM serial number, the version about the software and hardware, the protocol version Run the DSP RETSUBUNIT command to query the antenna electrical down tilt information. Run the DSP RETDEVICEDATA command to get the Max. and Min. down tilt that the antenna can work..

3.2 Non-Alarm Maintenance This section describes the maintenance methods of the RET antenna no AIMM scanned or partial AIMMs scanned, and ALD link disconnection after addition of the ALD.

3.2.1 No AIMM Scanned or Partial AIMMs Scanned This section describes how to rectify the faults such as no logical modules scanned or less than four logical modules scanned during the configuration and operating the RET antenna. Issue 01 (2013-08-29)


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3 Maintenance

Background Information There are two kinds AIMM, Single motor module ( the one has only one motor inside) and Dual motor module( the one has two motor inside).The single motor module has two series numbers(SNs) which correspond with two logical modules( one RET module and one RAE module), the Dual motor module has four SNs which correspond with four logic modules ,( two RET module and two RAE module) Therefore, the SNs quantity be scanned must be littler than the right logical module quantity can be scanned per AIMM. After several times of scanning, the results are as follows: 

Case 1: The number of scanned SNs of logical modules is smaller than right logical module quantity. However, after several scanning attempts, all SNs can be scanned.



Case 2: After multiple scanning attempts, one or more SNs of logical modules still cannot be scanned.

Table 3-1 describes the symptom of no logical modules scanned or less than four logical modules scanned. Table 3-1 Symptom Symptom

Impact on the System

Severity

Cause

The number of scanned logical modules is smaller than right number

The AIMM antenna connected to the main eNodeB cannot be identified, configured, nor managed.

Major



The AIMM is not connected securely.



The ALD power switch is set to OFF.



The AIMM is faulty.



The eNodeB is faulty.



The antenna system is not compatible with the AIMMs.

Operation Procedure Step 1 Run the SCN ALD command and check the results. 

If all the logical modules are scanned, no further action is required.



If no logical module or partial logical modules are scanned, go to Step 2.

Step 2 Run the SCN ALD command repeatedly and check the results. 

If case 1 occurs, go to Step 3.



If case 2 occurs, go to Step 4.

Step 3 Run the LST RET command , and then run the RMV RET conmmand to remove the RET module if there is any RET module .Run the SCN ALD conmmand Scan more times to get the SNs. Run the ADD RET command to configure all the RET functions. Step 4 Run the DSP ANTENNAPORT command. Check whether the RET power supply is ON and all the parameters were correctly set.

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RET Antenna TD-LTE Maintenance Guide 

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If the power supply switch is set to ON and parameters are set correctly, go to Step 5.

If the power supply switch is set to OFF, run the MOD ANTENNAPOR (OOK mode) or MOD RETPORT(RS485 mode) command to set the ALD power switch to ON .and the run the DSP ANTENNAPORT or DSP RETPORT command to check the current consumption. If it is normal go to Step 1 and if it is not normal ,go to Step 5 Step 5 For the logical modules that fail to be scanned, check whether the AIMM hardware is connected correctly. 

If the hardware is connected correctly, go to Step 6.



If the hardware is connected incorrectly, connect it again.and go to Step 1.

Step 6 If the RET antenna is used, replace the AIMM whose logical modules fail to be scanned, and go to Step 7. Step 7 Run the SCN ALD command and check the results. 

If all the logical modules are scanned, no further action is required.



If no logical module or less than four logical modules can be scanned, contact Huawei technical support engineers.

----End

3.2.2 ALD Link Disconnection After Addition of the ALD Background Information The RET Communication Abnormal Alarm is reported after the ALD is added during the application of the RET antenna. Then, run other MML commands and return to the ALD is not working alarm. Table 3-2 describes the symptom of the ALD Link Disconnection alarm after addition of the ALD. Table 3-2 Symptom Symptom


Severity

Cause

The alarm RET Antenna Maintenance Link Abnormal is reported after adding the ALD during the application of the RET antenna. Then, run other MML commands and return to the fault alarm ALD is not working

The communication link is not set up. Therefore, the interaction cannot be implemented between the main eNodeB and the standby eNodeB, and the main eNodeB cannot manage the RET antennas.

Major

When the ADD RET command is executed, a communication fault occurs.

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Operation Procedure Step 1 Run the RMV RET command to remove the ALD. Step 2 Run the ADD RET command to add the ALD. Step 3 Check whether the alarm is cleared on the LMT. 

If the alarm is cleared, no further action is required.



If the alarm persists, go to section 3.3.1 "RET Communication Abnormal."

----End

3.2.3 The Scanned SNs is not the antenna SNs,but the AIMM SNs Background Information The scanned SNs is not the antenna SNs, but the AIMM SNs, when the RET scanned ,the RET Table 3-3 describes the symptom of that. Table 3-3 Symptom Symptom


Severity

Cause

Run the SCN ALD command，the scanned SNs is not the antenna SNs, but the AIMM SNs,

The main station may not get the back board information

Major

The module may not connect well or the backboard may be not work



The antenna SNs illustration： RET module: HWM1234D90001012345r/HWM1234D90002543210y RAE module: HWX1234D90003567890r/HWX1234D90004098765y



The AIMM SNs illustration： RET module: HWB12345678901390011/HWB09876543211390022 RAE module: HWX14725836901390011/HWX96385274101390022

The last figure of the antenna SN, is the color-coding information ,but that of the AIMM SN is a number. The detail spec. about the SN please see the RET Antenna TD-LTE Configuration Guide.

Operation Procedure Step 1 Run the ADD RET command and configure the SN, after that and check whether there is any ALD Hardware Fault alarm； 

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If there was an ALD Hardware Fault alarm，please go to the Step 2


7

RET Antenna TD-LTE Maintenance Guide 

3 Maintenance

If there was no ALD Hardware Fault alarm, run the RMV RET command to remove all the modules and then go to Step 3.

Step 2 Run the RMV RET command to remove all the module ,check whether the module connect well and reconnect the module； Step 3 Run the SCN ALD command， 

If get the antenna SNs and the ALD Hardware Fault alarm disappeared after configure the module, and no further action is required.



If till get the AIMM SNs, contact Huawei technical support engineers.。

----End

3.3 Alarm Maintenance 3.3.1 RET Communication Abnormal Background Information The alarm RET Communication Abnormal is reported during the operation and maintenance of the RET antenna. The main eNodeB clears or does not clear the alarm according to the actual conditions of the link. Table 3-4 describes the RET Communication Abnormal alarm. Table 3-4 RET Communication Abnormal Symptom


Severity

Cause

The eNodeB regularly detects the status of the (Antenna Interface Standard Group) AISG link of the RET antenna. When the status is abnormal, the alarm RET Communicatio n Abnormal alarm is reported.

If the AISG link of the RET antenna is faulty, the electrical tilt of the RET antenna cannot be adjusted and the status of the RET antenna cannot be monitored.

Minor



Extra RET antennas are configured.



The AIMM is not installed or not work



In the irregular installation scenario, the vendor code and SN of the RET antenna are not configured or are configured incorrectly.



The RET antenna is faulty.



The ALD power switch of the eNodeB is set to OFF.



The cable is not connected securely to the eNodeB and the RET antenna.



The eNodeB is faulty.

Figure 3-1 describes the RET Communication Abnormal alarm.

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Figure 3-1 RET Communication Abnormal

Operation Procedure Step 1 Run the LST RET command, check the result, and check whether extra AIMMs are configured on the LMT. Check whether the AIMM reporting the alarm needs to be configured. 

If the AIMM reporting an alarm needs to be configured, go to Step 3.



If the configuration of the AIMM reporting an alarm is not required, run the RMV RET command to remove extra AIMMs. Then, go to Step 2.

Step 2 Check whether the alarm is cleared on the LMT. 




If the alarm persists, go to Step 3.

Step 3 Run the SCN ALD command. 

If all the AIMMs are scanned, go to Step 4.



If no AIMM can be scanned, go to section 3.2.1 "No AIMM Scanned or Partial AIMMs Scanned."

Step 4 Run the LST RET command to check whether the AIMM is correctly configured. 

If the AIMM is correctly configured, go to Step 5.



If the AIMM is not correctly configured, for example, the vendor code and SN of the AIMM are not configured or incorrectly configured, run the RMV RET command to remove the faulty AIMM.



Run the ADD RET command to add the AIMM and then go to Step 5.

Step 5 Check whether the alarm is cleared on the LMT 5 minutes later. 




If the alarm persists, perform the following operations:

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If the external RET antenna is used, go to Step 6.

−

If the internal RET antenna is used, contact Huawei technical support engineers. Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd

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3 Maintenance

Step 6 Replace the AIMM

ande check wether the alarm is cleared on LMT 5 minutes later.






If the alarm persists, contact Huawei technical support engineers.

----End

3.3.2 RET Motor Abnormal Background Information During the maintenance of the RET antenna, when the downtilt of the RET antenna is calibrated or adjusted, the motor is blocked and the RET Antenna Motor Abnormal alarm is reported. Table 3-5 describes the RET Antenna Motor Abnormal alarm. Table 3-5 RET Antenna Motor Abnormal Symptom


Severity

Cause

When the AIMM motor is faulty or the antenna is mechanically faulty, the alarm RET Antenna Motor Abnormal alarm is reported.

Because of the motor faults, the electrical tilt of the RET antenna cannot be adjusted.

Minor



The AIMM motor is faulty.



The antenna is mechanically faulty.

Figure 3-2 describes the RET Antenna Motor Abnormal alarm. Figure 3-2 RET Antenna Motor Abnormal

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Operation Procedure Step 1 Reset the RET antenna. 1.

Run the CLB RET command to calibrate the antenna.

2.

Run the MOD RETSUBUNIT command to set the electrical tilt of the antenna.

3.

Check whether the alarm is cleared on the LMT. −


−


Step 2 Upgrade the AIMM configuration files. 1.

Run the DLD RETCFGDATA command to load the AIMM software.

2.


3.


4.



−

If the alarm persists, perform the following operations: If the external RET antenna is used, go to Step 3. If the internal RET antenna is used, contact Huawei technical support engineers.

Step 3 Check whether the AIMM is securely connected to the antenna. 1.

Check whether the hardware is connected securely and correctly to the AIMM. −

If the hardware is connected correctly, go to Step 4

−

If the connection is improper, reinstall the AIMM.

2.

Run the CLB RET command to calibrate the antenna after about 3 minutes later(the AIMM and the base station would re-link after reinstall the module,).

3.

Run the MOD RETSUBUNIT command to set electrical tilt of the antenna；

4.



−

If the alarm persists, go to Step 4

Step 4 Replace the AIMM. 1.

Replace the faulty AIMM with a new one. Run the RMV RET command to remove the faulty AIMM, and rescan and reconfigure the new AIMM.

2.


3.


4.



−


----End

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3.3.3 RET Not Calibrated Background Information During the maintenance of the RET antenna, the RET Antenna Not Calibrated alarm is reported when calibrating the RET antenna fails. Table 3-6 describes the RET Antenna Not Calibrated alarm. Table 3-6 RET Antenna Not Calibrated Symptom


Severity

Cause

The RET Antenna Not Calibrated alarm is reported when calibrating the RET antenna fails.

The RET antenna is not calibrated. In this case, the electrical tilt of the RET antenna cannot be set, and the cell coverage under the RET antenna deteriorates.

Minor



The newly-installed RET antenna is not calibrated.



The AIMM is improperly installed to the antenna.



Downloading configuration data to the AIMM fails.



The AIMM is powered off abnormally during previous calibration. As a result, the AIMM cannot be located and calibrating the AIMM fails.



The antenna is mechanically faulty.

Figure 3-3 shows the RET Not Adjusted alarm. Figure 3-3 RET Antenna Not Calibrated

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Operation Procedure Step 1 Calibrate the RET antenna again. 1.


2.



−


Step 2 Load the correct configuration data to the AIMM. 1.

Run the DLD RETCFGDATA command to load configuration data.

2.

Run the CLB RET command to calibrate the antenna. −


−


Step 3 Check whether the AIMM is securely connected to the antenna. 1.

2.

Check whether the hardware is connected securely and correctly to the AIMM. −


−

If the connection is improper, reinstall the AIMM.



−


Step 4 Upgrade the AIMM. 1.

Run the DLD ALDSW command to load the AIMM software.

2.


3.

Run the MOD RETTILT command to set the electrical tilt of the antenna.

4.



−



Replace the faulty AIMM with a new one. Run the RMV RET command to remove the faulty AIMM, and rescan and reconfigure the new AIMM.

2.


3.


4.



−


----End

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3.3.4 RET Data Loss Background Information During the maintenance of the RET antenna, the RET Data Loss alarm is reported when the CLB ANT command is run to calibrate the RET antenna. Table 3-7 describes the RET Data Loss alarm. Table 3-7 RET Data Loss Symptom


Severity

Cause

During the calibration, the RET Data Loss alarm is reported when configuration data is not loaded to the AIMM.

The AIMM is not loaded with configuration data. In this case, setting the antenna tilt fails.

Minor



The AIMM is not loaded with the configuration data before it is delivered.



The flash memory of the RET antenna is damaged.

Figure 3-4 RET Data Loss

Operation Procedure Step 1 Load the correct configuration data to the AIMM. 1.

Run the DLD RETCFGDATA command to load configuration data.

2.


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RET Antenna TD-LTE Maintenance Guide −

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Replace the faulty AIMM. Run the RMV RET command to remove the faulty AIMM, and rescan and reconfigure the new AIMM.

2.


3.


4.



−


----End

3.3.5 RET Data Abnormal Background Information The RET Antenna Running Data and Configuration Mismatch alarm is reported when the tilt configured in the eNodeB is inconsistent with the actual tilt of the RET antenna due to the tilt setting failure. Table 3-8 describes the symptom of the RET Data Abnormal alarm. Table 3-8 RET Data Abnormal Symptom


Severity

Cause

The RET Data Abnormal alarm is reported when the eNodeB detects the inconsistency between the tilt of the RET antenna and the tilt in the configuration data.

The cell coverage under the RET antenna deteriorates.

Minor



The tilt set larger than the max. or litter the Min. tilt that the antenna can work.



The eNodeB cannot synchronize with the antenna when the RET antenna is reset and maintenance links are interrupted..



The configuration data of the RET antenna stored on the eNodeB is modified incorrectly.

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Figure 3-5 RET Data Abnormal

Operation Procedure Step 1 Calibrate the RET antenna again. 1.


2.



−


Step 2 Reset the RET antenna. 1.

Run the RST ALD command to calibrate the antenna.

2.


3.


4.



−


Step 3 Check whether the hardware is connected correctly. 1.

2.

Check whether the hardware is connected correctly. −


−

If the hardware is connected incorrectly, connect it again.



−


----End

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3.3.6 ALD Hardware Fault Background Information The ALD Hardware Fault alarm is reported when the RET backplane or AIMM of the LTE TDD system is faulty. Table 3-9 describes the ALD Hardware Fault alarm. Table 3-9 ALD Hardware Fault Symptom


Severity

Cause

The ALD Hardware Fault alarm is reported when the RET backplane or AIMM of the LTE TDD system is faulty.

The AIMM fails to normally control the downtilt of the RET antenna.

Minor



The pluggable module is loosely connected to the backplane.



The storage module on the backplane is faulty.



The pluggable module is faulty.

Figure 3-6 shows the ALD Hardware Fault alarm. Figure 3-6 ALD Hardware Fault

Operation Procedure Step 1 Reconfigure the RET antenna.

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1.

Run the RMV RET command to remove the ALD.

2.

Run the SCN ALD command to rescan the ALD.

3.

If the ALD SN is scanned, run the ADD RET command to add the ALD. −

If the scanned ALD SN is consistent with the former SN and the alarm is cleared, no further action is required.

−

If the scanned ALD SN is different from the former SN and the alarm persists, go to Step 2.

Step 2 Check whether the AIMM is securely and correctly connected to the antenna. 

If the AIMM is connected incorrectly, reconnect the AIMM to the antenna and then go to Step 1.



If the AIMM is connected correctly, go to Step 3.

Step 3 Replace the pluggable module and go to Step 1. 





Step 4 Replace the antenna. 





----End

3.4 Equipment Replacement Operation Procedure Step 1 Remove the AISG cable from the AIMM to be replaced. Step 2 Loosen the nuts on the AIMM with a wrench, and then remove the AIMM. Step 3 Install a new AIMM, and then connect the AISG cable to the AIMM. For more information about the AIMM installation, see the AIMM Installation Guide. Figure 3-7 Removing the AIMM

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Figure 3-8 Installing the AIMM

----End

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0A Appendix

A

Appendix

Acronyms and Abbreviations Acronym or Abbreviation

Full Name

AIMM

Antenna Information Management Module

AISG

Antenna Interface Standards Group

ALD

Antenna Line Device

LMT

Local Maintenance Terminal

MML

Man Machine Language

OOK

On-Off Keying

RET

Remote Electrical Tilt

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RET Antenna TD-LTE Maintenance Guide(01)

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