10-Mini-Link TN Troubleshooting Guide

MINI-LINK TN TROUBLESHOOTING GUIDE

Hadi balharith [email protected]

agenda Mini-link troubleshooting 1. 2. 3. 4.

TROUBLESHOOTING STEPS LINE OF SIGHT OUTDOOR INSTALLATION TROUBLESHOOTING TOOLS › › ›

5.

RF LOOP IF LOOP RF INTERFERENCE TEST

ALARMS/BEHAVIOUR ACTION PLAN › › › › › › › ›

FAR END NO CONTACT LOW MODULATION / ATPC NOT SYNC WITH RSL LAN DOWN RL-IME NO TRAFFIC WAN DOWN WAN LOWER LAYER DOWN HCC ALARM RCC ALAM

Mini-Link TN Troubleshooting Guide | Commercial in confidence | 2017-02-26 | Page 2

TROUBLESHOOTING STEPS 1. 2. 3. 4. 5. 6. 7.

Analysis. Problem replication/identification. Possible Faults with alarm messages Action Plan. Testing. Documentation. Follow Up.


Check line Of Sight. Low RSL and fading sometimes due to the LOS

For Example


Check antenna support and waveguide.  When you facing Low rsl , check the support arm , it should be perpendicular

Wrong

Wrong right

Wrong Mini-Link TN Troubleshooting Guide | Commercial in confidence | 2017-02-26 | Page 5

agenda Mini-link troubleshooting

› RF LOOP › IF LOOP


Rf loop test › Loops can be used to verify that the transmission system is working properly or they can be used to locate the faulty unit or interface in case of failure. › types of loops : 1. IF loop 2. RF loop 3. Rx loop


Rf loop test › To make RF LOOP 1. Right Click on the desired radio link 2. Select Radio Link Loops


RF LOOP TEST › For RF Loop , Click on RF box and the arrow color will change to blue › For IF Loop , Click on IF box and the arrow color will change to blue

RF Loop activated Mini-Link TN Troubleshooting Guide | Commercial in confidence | 2017-02-26 | Page 9

IF Loop activated

By setting the RF loop you can find out if the radio terminal is ok or not. When you have set a loop and the terminal is ok it should look like in the right hand example. There should be no alarms on the IF and RF level, but the HCC alarm on the modem will still be present. The input to the receiver (RX value) should be around -50 dBm ±10 dBm ( Rx= -60 to -40) . This is ok. Mini-Link TN Troubleshooting Guide | Commercial in confidence | 2017-02-26 | Page 10

If you get a lower value than the -50 dBm ±10 dBm the radio terminal can still be ok. But if the RF input level is below the threshold level for that modulation order you will still have a lot of alarms. This can be when high modulation orders are used. Try to set a lower modulation order to see if the alarms disappear. See the next slide for an example. Mini-Link TN Troubleshooting Guide | Commercial in confidence | 2017-02-26 | Page 11

Change to a lower modulation order and see what happens with the alarms. If all alarms disappear you know that the radio is ok, even if the received level is low. That is nothing that affects the radio in normal operation! Mini-Link TN Troubleshooting Guide | Commercial in confidence | 2017-02-26 | Page 12

 IF loop test to check the MMU functionality .



› RF INTERFERENCE TEST


Rf Interference

› In order to see if the ES / SES / UAT is a result of multipath fading and/or rain or a combination of fading and interference, the history of the input level needs to be examined. › If there has been ES / SES / UAT, but without the input level going below the receiver threshold, interference can be suspected. Mini-Link TN Troubleshooting Guide | Commercial in confidence | 2017-02-26 | Page 15

Maximum rf level @ tx off Channel spacing (MHz) 3.5 7 14 28 40 56


RF input level (dBm) -94 -91 -88 -85 -82 -82

Interference test › Interference Test Procedure : › Interference measurement can be tested on 2 ways based on SBL Release as follow :

1. Spectrum Diagnostics Tools : Only if the TN SBL ≥ 5.4FP ( R32K123 ) with Mini-Link craft 16A or higher

2. Manual interference test The manual test can be used with any SBL and only recommended for SBL < 5.4FP


Interference test › Interference Test Procedure : 1. Access the far-end terminal from MINI-LINK Craft and switch off the far-end transmitter. 2. Access the near-end terminal from MINI-LINK Craft and switch off the near-end transmitter. 3. For XPIC Links , Turn off both the V & H transmitter on the near end and far end › Note: › In a 1+1 system both transmitters must be switched off.


Spectrum Diagnostics Tools 1. Under Radio Links , Right Click on the desired radio link 2. Select Spectrum diagnostics in new window


Spectrum Diagnostics Tools 5. Select scan type = Channel Scan 6. Click Start Scan


Spectrum Diagnostics Tools The scan result graph will show the interference test results .  The left graph indicates no interference in the link since all the results is < -85 dBm for CS=28Mhz  While the right graph shows high interference on the whole channel

No Interference


High Interference

Spectrum Diagnostics Tools To get the interfere test report ; 1. Under Scan result , Choose Image , Click export 2. Also, Click CSV, Click Export


Manual Interference test › Interference Test Procedure : 1. Access the far-end terminal from MINI-LINK Craft and switch off the far-end transmitter. 2. Access the near-end terminal from MINI-LINK Craft and switch off the near-end transmitter. 3. Measure the received RF input level for the operating center frequency. If the level exceeds the RF input level stated in below tables, consult the design department. 4. Repeat the measurement for all frequencies within the channel spacing in steps of 2 MHz. 5. Record the highest value on the Functional Test record. If any level exceeds the RF input level stated in the table below, consult the design department.


Manual Interference test for 1+0 link › Test Interference Example : › 1+0 link, Tx = 23030 Mhz & channel spacing = 28 Mhz


Manual Interference test for 1+0 link 1. Measure the received RF input level for the operating center frequency ( 23030). 2. Repeat the measurement for all frequencies within the channel spacing in steps of 2 MHz. 3. IF the Rx level < -85 dBm then the link suffer from Interference.


Manual Interference test FOR XPIC 2+0 LINK › Test Interference Example 2 : › XPIC 2+0 link, Tx = 12877 Mhz & channel spacing = 28Mhz

1. 2. 3. 4. 5. 6.

Turn off both the V & H transmitter on the near end and far end At the radio link configuration page, select the frequency check on the Rx level for that Freq Record RSL level on the "Measure RSL" for both V & H and upper & lower channel Change another freq, and Repeat step 2 to 5 until the whole frequency is measured IF the Rx level < -85 dBm then the link suffer from Interference.


Interference test FOR XPIC 2+0 ZRH705 V-Pol Slot 2 MHz from center frequency

MHz

ZRH705 H-Pol Slot 3 Measured Interferenece RSL Result

MHz from center frequency

MHz

Measured Interferenece RSL Result

12863

-80.2

Fail

12863

-90.3

Pass

12865

-79.8

Fail

12865

-90.5

Pass

12867

-79.4

Fail

12867

-90.5

Pass

12869

-79

Fail

12869

-90.6

Pass

12871

-79

Fail

12871

-90.8

Pass

12873

-78.7

Fail

12873

-91.2

Pass

12875

-79.1

Fail

12875

-91.1

Pass

Configured frequency 12877

-79

Fail

Configured frequency 12877

-91.8

Pass

12879

-79

Fail

12879

-91.8

Pass

12881

-79

Fail

12881

-91.8

Pass

12883

79

Fail

12883

-91.8

Pass

12885

-79

Fail

12885

-91.8

Pass

12887

79

Fail

12887

-91.8

Pass

12889

-81

Fail

12889

-91.8

Pass

12891

-89.6

Pass

12891

-91.8

Pass



5. ALARMS/BEHAVIOUR ACTION PLAN › FAR END NO CONTACT › LOW MODULATION / ATPC NOT SYNC WITH RSL › LAN DOWN › RL-IME NO TRAFFIC › WAN DOWN › WAN LOWER LAYER DOWN › HCC ALARM › RCC ALAM


Far End No Contact

Checks

Actions

Frequency TX/RX

Correct frequency to be set

Channel spacing

Same channel spacing on both sides

Spectral Efficiency Class

Same class on both sides

Tx power

Set according to design docs


LOW MODULATION / atpc not sync with rsl Checks

Actions

Check RSL

Check TX power If RSL not Ok , Then fine Tuning is Required

Check RAU software (R5A04) Check MMU software (R7D01) Check SBL software (R32K123)

Upgrade/downgrade should be planned

RAU/MMU RAU Functionality

MMU Functionality

RF Interference Mini-Link TN Troubleshooting Guide | Commercial in confidence | 2017-02-26

RAU/MMU Restart RF loop (verify if RAU is ok or not) expected received power ~ -40 and -60 dB IF loop (verify if MMU is ok or not) All Alarms should be cleared except HCC Also , The modulation should be cleared and if one end have lower modulation then replace MMU Perform full intereference Test for the whole channel spectrum. ( Refer to Interference Test Procesure) If interference found , Then E// TND team | Page 30 should provide new frequecny .

Low modulation troubleshooting ( MMU faulty case) › Example - Link is planned and configured 229Mbps with 256 QAM but in running state it is showing 128QAM. Because of Modulation dropped through put is coming less and link is running with error. › Troubleshooting Steps : 1. Give RF loopback at both ends. 2. If there is no error in RF loopback than give IF loop back. 3. No error. But at one end, IF loopback running on 128QAM So that means MMU is faulty


Low modulation troubleshooting ( MMU faulty case) › IF loopback enabled at NE , The results states that the Modulation is lower than the planned one


Low modulation troubleshooting ( MMU faulty case) › IF loopback enabled at FE , The results states that the Modulation is the same as the planned one


Low modulation troubleshooting ( MMU faulty case) › So then we replace the MMU at NE Site where IF loopback running 128QAM. › After the replacing MMU link running at 256 QAM.


Lan down Checks

Actions

Physical connection/cables

Cable OK, present and connected on other side

Admin Status

Set it "UP"

Parameters (Auto negotiation, Flow control, Speed)

Verify its identical in both sides

Check port Role in design (CN-UNI most of the times) LAN port belonging to ETU/NPU


Restart board Warning TRAFFIC AFFECTING

RL-IME No traffic Checks

Actions

Related packet link and MMU are working properly

-

Far End WAN settings completed (RL-IME associated to packet link)

Complete configuration on Far-End Remove and re-config RL-IME in the same RL-IME

everithing seems ok

Remove and re-config RL-IME in a spare RL-IME


WAN Down Checks

Actions

Check RL-IME is OK Check Switch port association and switch port status Check Port Role (I-NNI for WAN) Re-do all previous steps also on far end side everithing seems ok


Reload Ethernet Switch

WAN lower layer down Checks

Actions

Cold Restart

Cold Restart the NE & FE Nodes Verify the Radio ID in Both Ends is correct and DCN Only Radio ID / DCN Only box is unchecked MMU & RAU SW Check MMU & RAU SW version compatibility with SBL Check TX power If RSL not Ok , Then fine Tuning is Check RSL Required Perform intereference Test for the whole channel spectrum RF Interference ( Refer to Interference Test Procesure) Frequency Check the Tx & Rx frequency is matched between NE - FE Check RAU connection and polarisation (ex: one site is V RAU connection and polarisation the other is H) or the XPIC cable is problematic

1- Change the MMU slot position , if nothing happened then PtP is clear NPU/PtP bus/MMU Functionality 2- Warm Restart the node , check if all the other RL-IMEs are up so the NPU is OK 3- Replace the MMU Mini-Link TN Troubleshooting Guide | Commercial in confidence | 2017-02-26 | Page 38

HCC alarm Checks

Actions

1- Make IF loop, if the alarm cleared so the MMU & IF cable is OK, If not cleared then replace MMU check the hop with the both loop 2- Make RF loop, if RF is not able to clear the alarm then IF & RF loop the RAU is faulty, if after giving RF loop the alarm cleared then this site is OK now check the far end with same loop's. check the SW Release Check Tx & Rx Frequencty RF Interference

upgrade to Latest SBL check frequencies and MMM IDs at both sides check interference at both sides Warm or Cold restart MMUs


Rcc alarm

Checks

Actions

Check Outdoor Connectors

The most common cause of RCC alarm is the outdoor connector loose , check it properly then check the IF cable

RAU Functionality

RF loop (verify if RAU is ok or not) expected received power ~ -40 and -60 dB

MMU Functionality

IF loop (verify if MMU is ok or not) All Alarms should be cleared except HCC




10-Mini-Link TN Troubleshooting Guide

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