Trouble Shooting - Case Analysis

8/11/2019 Trouble Shooting - Case Analysis

1/26

2008, ZTE Corporation. All rights reserved. 1

Trouble Shooting - Case Analysis

Sun Changyu 1 537 7


2/26


3/26


4/26

2006, ZTE Corporation. All rights reserved.

ZTE Proprietary & Con fidential

Presentation for WiMAX Network

4

OMC alarms as No WTRX detected and No WDPA detected

Reason:

1. OMC data configuration is well done.2. The cable connecting RRU and BBU is not qualified or destroyed.

3. The optical fiber connecting RRU and BBU is not well connected with the optical

connection ports at both ends.

4. The type of optical fiber is not matched to the type of optical connectional ports.

5. RRU software version is not matched to the software versions of BBU and OMC.

6. TX and RX ports of optical fiber are not correctly assembled at the factory (that is that

TX port is assembled at the fiber end where RX port should have been assembled).

7. RRU is not powered on.8. RRU hardware is problematic.

Measurement:

1. Make sure connection relationship between Segment and TRX is configured or not.

2. Check power supply of RRU and measure power feeder cable voltage to make sure it is

within the requested range. ( the voltage should be about -53V without load)

3. Make sure optical fiber and optical connection ports are qualified(refer to for the quality

checking process)

4. Update RRU software version to make it catered to the software versions of BBU and

OMC.

5. Power off ,and then power on all equipment at BS side to reset the system.

6. Take off RRU and test RRU hardware.


5/26




5

Abnormal WDPA VSWR


6/26




6

OMC Alarm-Abnormal WDPA VSWR and Closed WDPA Channel


7/26 2006, ZTE Corporation. All rights reserved.



7

Reason:

1. The antenna feeder cable of PA channel 0 is not well connected.(feeder cable broken, water soaking in)

2. Frequency range of RRU DL signal is out of RFE frequency

range.

Measurement:1. Make sure RRU central frequency is correctly configured

according to the requested frequency range written on RRU

equipment label.

2 Change feeder cable or redo the feeder cable waterproof disposal.

3 Reset RRU and the alarm would be disappeared, if notdisappeared, changed RRU


8/26 2006, ZTE Corporation. All rights reserved.ZTE Proprietary & Con fidential


8

Closed WDPA Channel 0/1




9

OMC Alarm-Closed WDPA Channels at the same time


10/26




11

RRU Tx0/Tx1 auto calibration failure




12


Reason 1:WDPA is power-off with power amplifier disabled, auto calibration will fail.




13


Reason 2:

forward link is abnormal, RRU auto calibration will fail




14


Reason 3:

RRU auto calibration failure can also be caused by abnormal calibrationprocessing internally in RRU - a




15


Reason 4:

Caused by abnormal calibration processing internally in RRU-b




16

Some RRU configurations Error





17

RRU Board Type Configuration Error

RRU can not detected from omc ,but can find one alarm The board type

is not consistent with that configured on OMC

R9100(2x4) R911048

WPTR TRWC_B





18

RRU Antenna Ability Parameter Checking Error

RRU antenna mode configured at OMC is beyond the actial antenna-supporting ability of the type of RRU in the system

R9100

WPTRR911048

WPTR TRWC_B

24 or 22 24 or 48





19

RRU Parameter Configuration Failure

RRU Radio Frequency Configuration is out of Range


20/26





21

Case1: How to check the RRU working normal if no any alarm on OMC?

Spetrum scan 1: normal with some users on-line





22

Case1: How to check the RRU working normal if no any alarm on OMC?

Spetrum scan 2: abnormal with some outsides interference


23/26


24/26


25/26


26/26

Documents

Trouble Shooting - Case Analysis