AMX DRPerformance Report

Week 02

Date: 13/01/2012

Tuning Fnoffset for reducingdrop due to bad quality in 2G

RF Senior Service Engineer: Guichard SUY

FNOFFSET CHANGES REPORT | Commercial in confidence | 2013-11-13 | Page 2 (20)

This document has the objective to show the result of tuning the parameters FNOFFSET

The impact on quality and mobility on the network

How could be help reducing drop due to bad quality either improve SQI

CONCLUSION

introduction

FNOFFSET CHANGES REPORT | Commercial in confidence | 2013-11-13 | Page 3 (20)

Definition:FNOFFSET (Frame number offset) define the time difference in which each frame number will be transmitted within a site from the FN generator in the BTS. Default value: 0 Range 0 – 1325 Unit: TDM Frames

Setting:To prevent that all cells on a site send BCCH channels at the same time we to define a deviation with respect to the FN generator called in order to reduce the time for decoding BSIC.

Sector A: FNOFFSET=0Sector B: FNOFFSET=4Sector C: FNOFFSET=8

This mean that Sector A will transmit frame number 0, sector B will transmit this same frame number 0, 4 frames later and 8 frames later for sector C and go on.

This setting is more useful on FLP 1/1 networks where all the three sectors operates under the same Hopping Frequency set. It decreases the interference condition, thus making possible a better

decoding of the TSC value which should correspond to the BCC part of the BSIC.

NB: The three sectors have different Hopping Frequency set on this presented tuning

CHANGES OF FNOFFSET 1/2

FNOFFSET CHANGES REPORT | Commercial in confidence | 2013-11-13 | Page 4 (20)

Requirement:TSC within a cell must be the same for all CHGR to ensure synchronization on that cells

Process:

• TSC was checked for all the cells in the network to ensure all CHRG within a cell has same TSC.

• Implementation was done in trial cluster, after satisfactory result it’s implemented overall network zone per zone

ResultThe following slides show the result in one of the zone implemented(883 Cell)[all the zone show the same results]

• The impact on quality and mobility on the network

• Show how could be help reducing drop due to bad quality and improve HO success rate

CHANGES OF FNOFFSET 2/2

FNOFFSET CHANGES REPORT | Commercial in confidence | 2013-11-13 | Page 5 (20)

UL_RXQUAL improved 6% and DL_RXQUAL improved 10%.

IMPROVEMENT IMPROVEMENT

FNOFFSET

RXQUAL

FNOFFSET CHANGES REPORT | Commercial in confidence | 2013-11-13 | Page 6 (20)

Improvement in SQI.

IMPROVEMENT

FNOFFSET

SQI

FNOFFSET CHANGES REPORT | Commercial in confidence | 2013-11-13 | Page 7 (20)

SDCCH TRAFFIC AND BLOCKING ARE STABLE

STABLE

FNOFFSET

Sdcch traffic & SdCchblocking

FNOFFSET CHANGES REPORT | Commercial in confidence | 2013-11-13 | Page 8 (20)

IMPROVEMENT IN CS NO RETAINABILITY(Sites out of service after that go back to normal)

IMPROVEMENT

FNOFFSET

CS NO RETAINABILITY

Sites out of service

FNOFFSET CHANGES REPORT | Commercial in confidence | 2013-11-13 | Page 9 (20)

CS INACCESIBILITY STABLE

STABLE

FNOFFSET

Sites out of service

Cs inaccesibility & components

FNOFFSET CHANGES REPORT | Commercial in confidence | 2013-11-13 | Page 10 (20)

REDUCTION OF DROP BAD QUALITY VOLUME

FNOFFSET

DROP CAUSES

Sites out of service

FNOFFSET CHANGES REPORT | Commercial in confidence | 2013-11-13 | Page 11 (20)

REDUCTION OF DROP DUE TO BAD QUALITY AS EXPECTED.

IMPROVEMENT

FNOFFSET

NUMBER OF DROP DUE TO BAD QUALITY

FNOFFSET CHANGES REPORT | Commercial in confidence | 2013-11-13 | Page 12 (20)

THE NUMBER OF DROP IS REDUCED.

IMPROVEMENT

FNOFFSET

DROP EVENTS

Sites out of service

FNOFFSET CHANGES REPORT | Commercial in confidence | 2013-11-13 | Page 13 (20)

IMPROVEMENT IN RETAINABILITY PS AFTER THE CHANGES

IMPROVEMENT

PS NO RETAINABILITYFNOFFSET

Sites out of service

FNOFFSET CHANGES REPORT | Commercial in confidence | 2013-11-13 | Page 14 (20)

IMPROVEMENT IN HO SUCCESS RATE.

IMPROVEMENT

FNOFFSET

HO SUCCESS RATESites out of service

FNOFFSET CHANGES REPORT | Commercial in confidence | 2013-11-13 | Page 15 (20)

› By doing this tuning we have improvement in quality, HO success rate and reducing drop call due to bad quality.

› It’s recomended to tune this parameter in network with dropfor bad quality or/and limitation with frequency plan ornetwork with FLP 1/1(Same group of hoppping for allsectores within a site).

› Pre-check of TSC configuration is mandatory, TSC of allCHGR within a cell must be unique.

CONCLUSION