BASIC OPTIMISATION PROCESS

THERE ARE 4-TYPES OF TYPICAL RADIO PROBLEM. THEY ARE

1.     COVERAGE PROBLEM

2.     INTERFERENCE PROBLEM

3.     UNBALANCED POWER BUDGET PROBLEM

4.     CONGESTION PROBLEM.

COVERAGE PROBLEM & SOLUTION

IN THIS CASE  RX LEVEL IS POOR AT THE SAME TIME QUALITY CAN BE BAD.

INDICATIONS

1.       DROP CALLS

2.       NO NETWORK                                    CUSTOMER COMPLAINTS 
3.       TCH FAILURE RATE

4.       CDR

5.       LOW PROPORTION OF BETTER CELL HO                                                     OMC INDICATOR

6.       HIGH DL & UL LEVEL HO(POSSIBLY ALSO QUALITY)
7. POOR LEVEL(< -95 dBm)                                                                       DRIVE TEST RESULT

OPTIMISATION

1.       CHECK ANTENNA SYSTEM(AZIMUTH,HEIGHT,TILT)

2.       INCREASE/DECREASE DOWNTILT AS PER REQUIREMENT

3.       CHECK BTS OUT-PUT POWER IN OMCR(SHOULD ALWAYS SET TO ZERO)

SOME TIME LEVEL IS OK IN THE STREET BUT POOR INSIDE THE BUILDING DUE TO BUILDING LOOSES (-10 TO -30 Db OR MORE).

INTERFERENCE PROBLEM

IN THIS CASE RX LEVEL IS GOOD BUT  RX QUALITY IS BAD.

INDICATORS

1.       BAD SPEECH QUALITY(NOISY CALLS)

2.       CALL DROP.                                                                         CUSTOMER COMPLAINTS

3.       SDCCH/TCH DROP

4.       LOW PROPORTION OF BETTER CELL HO

5.       HIGH RATE OF UL/DL QUALITY HO & INTERFERENCE HO                             OMC INDICATOR

6.       LOW HOSR

7.       RXQUAL>4 WITH RXLEVEL> -85 dBm                                                          DRIVE TEST

OPTIMISATION

1.       ANTENNA OPTIMISATION

2.       FREQUENCY (BCCH)  CHANGE

3.       REDUCTION OF BTS POWER

UNBALANCED POWER BUDGET PROBLEM

TOO HIGH PATH-LOSS DIFFERENCE BETWEEN UL & DL(OFTEN  DL>UL)

REASONS

1.       CROSSED FEEDERS

2.       LOOSE CONNECTORS

3.       FAULTY ANTENNA,FEEDER,TMA

INDICATORS (OMC-MAINLY)

1.       HIGH RATIO OF UPLINK LEVEL HO CAUSE

2.       LOW INCOMMING HO SUCCESS RATE

3.       DL LEVEL LOOKS OK FOR HO BUT UL IS TOO WEAK WHEN HO IS ATTEMPED

4.       DEGRADATION OF TCH FAILURES & OC CALL DROP INDICATORS

5.     VSWR ALARM

6.     TMA ALARM

OPTIMISATION

THE FOLLOWING EQUIPMENTS SHOULD BE CHECKED

1.       TRX TYPES (MP, HP)

2.       ANTENNAS OR COMMON RF COMPONENTS, TMA(COMMON TO ALL TRX OF THE BTS)

3.       TRX RF CABLES,LNA

CONGESTION PROBLEM

TCH CONGESTION RATE ( TCH ASSIGNMENT PHASE) IS TOO HIGH(MORE THAN 2%)

INDICATORS

1. COSTOMERS COMPLAIN ABOUT NETWORK BUSY

2. HIGH “TCH CONGESTION RATE” RTCH ASSIGNMENT FAIL-CONGESTION                        OMC

3. LOW INCOMING INTRA/INTER BSC HO SUCCESS RATE                                        

4. HIGH DIRECT RETRY/CONGESTION RELIEF IF ACTIVATED

5. HO TO BETTER CELL IS SLOW OR NEVER OCCURS                          DRIVE TEST

OPTIMISATION

HARDWARE SOLUTION

1.       TRX ADDITION

2.       ACTIVATE HR

3.       NEW SITE ADDITION

4.       CELL BOUNDARY OPTIMISATION TO SHARE TRAFFUC WITH SURROUNDING CELL.

      SOFTWARE SOLUTION

1.       DIRECT RETRY

2.       TRAFFIC HANDOVER

3.       HALF RATE(ALCATEL)

4.       CONGESTION RELIEF

5.       FLOW CONTROL(MOTOROLA)

HANDOVER OPTIMISATION

WHEN HOSR IS POOR HANDOVER OPTIMISATION IS REQUIRED

THE PROCESS IS AS FOLLOWS:-

1.       CHECK NEIGHBOUR RELATIONS

2.       CHECK HOSR WITH NEIGHBOURS FROM OMCR STATS

3.       ADD/DELETE NEIGHBOURS AS PER REQUIREMENT

4.       REDEFINE EXISTING NEIGHBOURS.

5.       SET HO-MARGIN PARAMETER DEPENDING UPON STATS

CALL DROP OPTIMISATION

1.       HANDOVER OPTIMISATION

2.       CHECK REMOTE TC DROP FROM DAILY DASH BOARD, IF HIGH – INFORM OMC

3.       CHECK INTERFERENCE BANDS IN DASH BOARD. BAND 1 & 2 FOR CO & ADJACENT CHANNEL INTERFERENCE-IF HICH----- CHECK FREQUENCY PLAN.

IF HIGH IN BAND 5------ FILTER FAULTY------INFORM OMC & BSS TEAM

4.       IF TRX DROP IS HIGH-

a.       CHANGE CALL PRIOTITY

b.       IF BCCH DROP IS HIGH- SHIFT BCCH TRX

c.       CHECH TRX EFFICIENCY----IF POOR-----GIVE A RESET------IF NO RESULY COMES------CHANGE IT

POINTS TO REMEMBER

1.        SDCCH BUSY HOUR- TYPICALLY MORNING HOURS(FREQUENT ON/OFF AND UPDATES)

2.        TCH BUSY HOUR-       HEAVY CALL TRAFFIC HOURS(COULD BE BACK HOME HOURS)

3.        HOLDING TIME-   AVERAGE TIME SPENT ON ANY DEDICATED RESOURCES.

4.        SDCCH HOLDING TIME- TYPICALLY 3-4 SEC

5.        TCH HOLDING TIME- ACTUAL CALL DURATION+ ALERTING