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silverlemone
2013-11-08, 03:04 AM
34153

Please any LTE expert help me investigate LTE problem

I cannot not handover from sector 2 to sector 1 in LTE network
I have already add co-cell neighbor and also other parameter have been added followed the guideline

Im very new on LTE ,and been checking in RRC message but still have no idea.
Please anybody help me , it would be appreciate

This is further information

Sector2 PCI:413 SCR:489
Sector1 PCI:411 SCR:488

LTE and UMTS on network :2100 Mhz

xsdenied07
2013-11-08, 04:20 AM
Dear the problem is ( RACH reason: Radio link timeout)

003890 02:09:08.051 Nemo RACH Info

Cellular System: LTE FDD
RACH type: 1,
RACH reason: Radio link timeout,
RACH result: Succeeded,
Max preambles: 10,
Preambles: 1,
Preambles failures: 0,
Preambles successes: 1,
RACH cont. failures: 0,
Pathloss: 93.00 dB,
Init TX power: -11.00 dBm,
Preamble step: 2.00 dB,
RACH PUSCH power: -5,
RACH preamble index: 9,
RACH access delay: 24 ms



34153

Please any LTE expert help me investigate LTE problem

I cannot not handover from sector 2 to sector 1 in LTE network
I have already add co-cell neighbor and also other parameter have been added followed the guideline

Im very new on LTE ,and been checking in RRC message but still have no idea.
Please anybody help me , it would be appreciate

This is further information

Sector2 PCI:413 SCR:489
Sector1 PCI:411 SCR:488

LTE and UMTS on network :2100 Mhz

xsdenied07
2013-11-08, 04:41 AM
Radio Link Failure is Physical Layer break and in most case this failure is unintentional.

UE may assume that Radio Link is broken due to the following.

The measured RSRP is too low.
It failed to decode PDCCH due to low RSRP

eNodeB may assume that that Radio Link is broken due to the following.

SRS Power SINR from UE is to much lower than what eNB configured for the UE.
eNodeB couldn't detect any NACK nor ACK from UE for PDSCH

:):)





Dear the problem is ( RACH reason: Radio link timeout)

003890 02:09:08.051 Nemo RACH Info

Cellular System: LTE FDD
RACH type: 1,
RACH reason: Radio link timeout,
RACH result: Succeeded,
Max preambles: 10,
Preambles: 1,
Preambles failures: 0,
Preambles successes: 1,
RACH cont. failures: 0,
Pathloss: 93.00 dB,
Init TX power: -11.00 dBm,
Preamble step: 2.00 dB,
RACH PUSCH power: -5,
RACH preamble index: 9,
RACH access delay: 24 ms

silverlemone
2013-11-08, 09:23 AM
Thank for all you guys

I am pretty sure that there is no problem about coverage and quality(RSRP or SIR too low)
I just cant figure but it might from some wrong configuration in transmission or wrongly parameter add
in the log file,you'll see that RSRP was going down before its gonna hand to another sector but it cannot
Normally it should hand before RSRP go decrease that low, so far i even have no idea why'd LTE request to hand to UMTS because
the priority parameter was correctly added

Are some alarms causing this issue ,i have observed ,there is a alarm which the cause was referred about "plane service mode"
But im not sure

Anyway its still can hand to Macro cell(outdoor area or another cell outside building)
this site is IBC

jukreew
2013-11-08, 02:34 PM
List EUTRANEXTERNALCELLS and EUTRANINTRAFREQ of this site and check PCI conflict.

your problem is Intra EnodeB handover so may be some config same PCI conflict on EUTRANEXTERNALCELL and EUTRANINTRAFREQ.