drsnk13 - high dcr_u21-ryg0093-2a & u21-ryg0028-2a

8/12/2019 DRSNK13 - High DCR_U21-RYG0093-2A & U21-RYG0028-2A

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DRSNK13

U21-RYG0093-2A & U21-RYG0028-2A

17/17/2014


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U21-RYG0028-2A

7/17/2014 2

Increase in UL Synch drops observed since 16thof May.


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Site Location

7/17/2014 3

The cells under question are neighbors to each other. The intersite distance is 3km. However U21-

RYG0028-2A is overshooting beyond 5km as shown in the next slide


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U21-RYG0028-2APropagation delay

7/17/2014 4

U21-RYG0028-2A is overshooting beyond 5km


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Traffic Carried by both cells

7/17/2014 5

The traffic carried by U21-RYG0093-2A has increased 3 folds since 16thMay whereas that carried by U21-RYG0028-2A more or less

remained the same.


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U21-RYG0093-2A

7/17/2014 6

The IRAT success rate of cell U21-RYG0093-2A has degraded with cells RYG028A and RYG093A since 16thMay with a subsequent increase

in pmNoFailOutIratHoSpeechReturnOldChPhyChFail . This means that IRAT failures have occurred due inability to allocate physical

resources.


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U21-RYG0028-2A

7/17/2014 7

The IRAT success rate of cell U21-RYG0028-2A has degraded with cells RYG028A and RYG093A since 16thMay with a subsequent increase

in pmNoFailOutIratHoSpeechReturnOldChPhyChFail . This means that IRAT failures have occurred due inability to allocate physical

resources.


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2G CellsTCH Blocking

7/17/2014 8

There is an increase in traffic and increase in TCH blocking in RYG093A although the traffic carried after increase is not

high.


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RYG093ARxQual UL & DL

7/17/2014 9

There is a sudden increase in RxQual % in UL with a subsequent decrease in RxQual % in DL since 17thMay.


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2G CellsTCH Blocking

7/17/2014 10

However no blocking was observed in cell RYG028A and the traffic too is consistent.


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RYG028ARxQual UL & DL

7/17/2014 11

The RxQuality too of RX028A has remained consistant which is natural behaviour.


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RYG093a & RYG028ASD Drop

7/17/2014 12

SD Srop of both RYG093A and RYG028A have also increased since 16thMay


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Observations and Conclusion

7/17/2014 13

The following observations were made

Judging by the difference in DL and UL Quality samples in RYG093A it is possible that there is path imbalance in the

2G cell which has led to increased IRAT failures with the cell

Although there is a traffic rise in both WCDMA cell U21-RYG0093-2A and GSM cell RYG093A, there is no increase intraffic of cells U21-RYG0028-2A and GSM cell RYG028A.

The rise in UL Synch drops could be due to increase in IRAT failures since intersite distance is large.

Also, since U21-RYG0028-2A is overshooting and is unable to have successful IRAT handovers with RYG093A there

is an increase in call drops in the cell.

No Parameter discrepancies were observed.

Action Plan

Need to check Hardware of GSM cell RYG093A and verify for hanged TRXs.

Downtilt U21-RYG0028-2A to minimise overshooting.


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147/17/2014

drsnk13 - high dcr_u21-ryg0093-2a & u21-ryg0028-2a

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