PERFORMANCE IMPROVEMENTCSSR CDR After TCH ASS HOSR TCH Call Block BH & SDCCH Block BH ULQ0-5 & DLQ0-5 1. Reduce TCH Blocking Activate DualRate (TCHF TCHD) In Blocking Cells Reduce SD Chanel In DualRate (TCHD) Cells With No SD Block Traffic Share 2. Quality Of TRX Problem Unbalance UL-DL Quality (ND 196) Swap BCCH Into Better Quality TRX Fix Hardware Problem Poor ULQ may be caused By Overshooting Poor DLQ may be caused By Coo-Chanel / Interference 3. Coverage Adjustment Timing Advance (ND232) Data Cell Distance Range Distribution Per Cell Rx Level Plot List Propose Mechanical Adjustment 4. Decrease Drop Call Rate Fix Hw Problem Verify Hw Problem On Pendem1 And Sengkaling3 Coverage Adjustment (ND232) Change Mechanical Adjustment (Tilt And Reorientation) Audit TRP - Trx_Priority_In_Tch_Alloc (ZEQO) Push Traffic Camped In Better Quality TRX Audit Adjacent Set HO Parameter in Sites Which Has Low HOSR (ND153) 5. Decrease Call Drop With Adjust Voice More Priority Then Data GPRS Setting TRX with the best quality as priority voice (ZEQO parameter TRP) Setting TRX with less quality TRX as priority for data service (ZEQO, ZEQV parameter BFG) Activate GTRX just only on TRX with less quality so traffic data GPRS only available on it (ZERO) Adjust parameter CDED & CDEF for GPRS capacity, so availability for GPRS can be constantly (ZEQO) 6. Interference Check adjacent frequency Check MAL list, BSIC, MAIO Step Check TO_B1 Tunning power control

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MML COMMAND & ND ANALYSIS for OPTIMIZATION1. 2. 3. 4. ZERO, ZEQO, ZEAO, ZEEI, ZEHO collect data parameter ND153 : Check ADJACENT ND196 : Check TRX Quality ND232 : Check Timing Advance

MML COMMAND TROUBLESHOOTING:

ZEOH:2008-07-04:NR=xxxx; ZERS:BTS=xxxx,TRX=xx,CH=xx:U; ZERS:BTS= xxxx,TRX= xx:L; ZDTI:::PCM=ET; Status LAPD ZDTC:T0769: Signaling ZEEI::BCSU; Kapasitas trx per BCSU ZUSI:BCSU; Status spare BCSU ZEQO:BTS=XX:MIS; Check configure FRL/FRU ZEAO; Adjcent cell ZYMO: Status transmisi BER 0 3. MS class Allowed.

B

C1 = (Rx_lev Rx_lev_Access_Min) Max(MS_TxCCH,0 MS_Tx Power) Cell Reselect Hysteresiss Hyst = 4 dB 14 dB Cara membatasi coverage: 1. Down Tilt. 2. MS_TxCCH. 3. Rx_lev_Acces_min. 4. Reduce Power. 5. Adjacency. 6. Negative C2 = C1 CRO (Cell Reselection Offset) with PT(Penalty Time) = 31. 7. Coba: Retrans = 1. D_max = 9 (Untuk membatasi coverage, due to rural area) Parameter Access No = cell barred PLMN permitted : 0 7 active. Yang perlu diperhatikan untuk create handover target: LAC, CI, BSIC, BCCH. Jika antar MSC, loading MML and RNW. TSC = BCC. Power control = disable. Layering: Untuk idle mode: - Macro GSM - Macro DCS, C2 = C1 + CRO (10 dB with PT=10 detik) - Micro GSM - Micro DCS - Indoor. Untuk Dedicated Mode - FMMS - AUCL = -80 - FMT = 4 s.

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HANDOVER Note: HO terjadi saat MS terkoneksi (dedicated), pada saat idle disebut Cell Selection atau Cell Reselection Terjadinya HO pada Cell Server ditentukan oleh: 1. 2. 3. 4. 5. 6. PBGT (Power Budget) Level DL / Level UL Quality Time Advance Umbrella FMMS (Fast Moving Mobile System)

Note: Normal HO di set sesuai Power Budget, Emergency HO di set sesuai Level, Quality, Time Advance, Umbrella, FMMS Pada PBGT HO terjadi saat Source HO dan Target HO terjadi selisih 4 dbm hingga 10 dbm, tergantung Margin yang diset (Margin Minimum=4 db) Kondisi Server HO dan Target HO sebelum terjadi HO Server BCCH 12 Signal Strength -60 db Quality 0 TA 1 Kondisi Server HO dan Target HO setelah terjadi HO Server BCCH 12 Signal Strength -75 db Quality 0 TA 2 N1 (Neighbour 1) 14 -75 db 0 2 N1 (Neighbour 1) 14 -60 db 0 1

Signal Strength antara Server dan Target HO telah memenuhi syarat Margin 4-10 dbm Pada Level DL/UL terjadinya HO di set sesuai tingkat level yg telah di set (-95 dbm Source harus HO ke Target) Kondisi Server HO dan Target HO sebelum terjadi HO Server BCCH 12 Signal Strength -60 db Quality 0 TA 1 Kondisi Server HO dan Target HO setelah terjadi HO Server BCCH 12 Signal Strength -95 db Quality 0 TA 2 N1 (Neighbour 1) 14 -75 db 0 2 N1 (Neighbour 1) 14 -60 db 0 1

Secara normal Source harus sudah HO ke Target, karena HO di set pada level -95 dbm maka HO belum bias terjadi, ketika level signal strength mencapai -95 dbm Source baru HO ke Target

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HO Layering (Umbrella dan FMMS) Umbrella Terjadinya HO dari sistem GSM900 ke DCS1800 di tentukan oleh nilai AUCL (AUCL=-75 dbm), saat MS mendekati dual band site (GSM900 dan DCS1800) secara otomatis DCS1800 akan bertindak sebagai Server, setelah menjauh dari site baru GSM900 yang menjadi Server FMMS Ditentukan oleh nilai FMT (Fast Moving Threshold) FMT=5 detik Call Setup GSM Server=-50 N1 DCS=-90 Connected GSM Server=-50 N1 DCS=-80 HO DCS Server=-80 N1=-55

HO Saat Idle HO 1 = Cell Selection HO 2 = Cell Recelection Hysterisis (CRH) HO 2 terjadi jika threshold = 6 dbm atau sesuai nilai CRO (Cell Reselect Offset) yg ditentukan C1 = Nilai Level Server yg sebenarnya C2 = Nilai Level Server setelah dilogik dengan nilai CRO Server=-74 N1=-70 Secara normal harus terjadi HO ke N1, tetapi CRO sudah diset 6 dbm maka secara logical level Server menjadi -74 + CRO(6 dbm) sehingga tidak terjadi HO ke N1

KASUS-KASUS GSM 1. Signal Strength Low 2. Bad Quality 3. HO Fail 4. Call Drop 5. Call Block 6. Call Setup Fail Signal Strength Low Server DCS = -97 GSM = -80 Kemungkinan penyebab: - New Site? - Antenna Tilting? - Antenna Clearance? - BTS Installation? Server GSM lebih kuat dari DCS nya Kemungkinan penyebab: - Neighbour belum di create - BCCH TRX bermasalah - BCCH TRX Low Power

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Server DCS lemah GSM kuat Kemungkinan penyebab: - AUCL terlalu kecil Server DCS kuat GSM lemah Kemungkinan penyebab: - TRX problem - DCS Insatallation problem Server GSM kuat DCS lemah Kemungkinan penyebab: - DCS Installation problem - Umbrella (AUCL=-75) Note: Kurangnya HO bisa mengakibatkan Signal Strength Low dan Bad Quality sehingga dapat menyebabkan Dropped Call or Blocked Call. HO Fail Kemungkinan penyebab: - Signal Strength Low - Timer Expire - Inter MSC - Inter BSC - Synchronization Fail (clock) Call Drop Kemungkinan penyebab: - Signal Strength Low - Bad Quality - Target HO belum di buat Call Setup Fail Kemungkinan penyebab: - Signal Strength Low - Bad Quality - Unpropper Neighbour (Tetangga yg tidak sesuai) Call Block Kemungkinan penyebab: - Signal Strength Low - Bad Quality - Target HO belum di buat

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Analisa Pada sesi drivetest, Untuk analisa sebaiknya kita gunakan Rx full atau sub? Perlu diketahui bahwa: 1. Bila DTX diaktifkan Maka perlu digunakan Rx sub 2. Rx sub merupakan pengukuran lebih kecil dari Rx full untuk idenifikasi sinyal dengan data kosong atau tidak. 3. Jika DTX dimatikan pengukuran lebih valid dengan Rx full begitu juga sebaliknya. 4. BER jelek mungkin ada gangguan signaling dari tx transmit, antara air interface BTS dan yang diterima oleh ms 5. angka half rate 0-17, full 17-26 enhance rate 26-30 6. MS power sebagai indikasi power yang dipancarkan oleh MS, jika nilainya 0 maka power maksimal.

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REFERENSI NETWORK DOCTORNOKIA ND BROWSER OSS4.1 ======================================================= Fault Management 027 BTS outages breakdown over 10 days Configuration Management Find Cell 042 Whole radio networks sorted out by BSC, BCF, BTS (042) 043 All cells with LAC and CI (043) 050 Find locked BCFs, BTSs, TRXs and channels (050) 051 Find cells having GPRS enabled TRXs (051) Adjacencies 070 BTSs with maximum number of adjacencies (070) 071 Cells with minimum number of adjacencies (071) 074 Adjacencies of cells (074) Network Entities 090 Network configuration summary (090) 054 Segment configuration (054) Frequencies 111 Frequency plan (111) Checks 065 Adjacencies to non-existing or foreign cells (slow, 065) 060 Adjacency discrepancies (060) 061 Non-symmetrical adjacencies (061) 062 Frequency check of adjacent cells (062) 069 Adjacent cell double frequencies (069) 076 Adjacent cells with the same NCC, BCC and frequency (076) 067 Handover synchronization (067) 068 BTS parameter survey (068) 063 BTS audit (063) Performance Management BSS SDCCH and TCH Access, availability 134 Cells having RACH rejections (134) 130 Cells having SDCCH congestion (130) 135 Cells having TCH congestion (135) 138 Cells having TCH blocking, raw and call blocking (138) 139 Cells having unavailable radio timeslots (139) Handover 150 Cells having high HO failure ratio (150) 153 Adjacencies having high HO failure ratio (153) 154 Handover cause distribution, by cells (154) 151 Common BCCH, Multi-BCF HO, cell-level (151) 151 Common BCCH, Multi-BCF HO, BSC-level (151)- 10 -

282 Cell Reselection, BTS level (282) 288 Cell Reselection, adjacency level (288) Drop Call 163 Cells having high TCH drop call ratio (163) 164 Transcoder failures (164) 166 SDCCH Drop ratio per cell (166) 167 Cells having high drop call count in handovers (167) Traffic and Load 182 Busy hour traffic for all cells (182) 181 Daily TCH traffic profile for a BTS (181) 185 Cells having maximum TCH traffic (185) 186 Cells having maximum paging traffic (186) 189 Cells sorted out by SDCCH or TCH holding time (189) Interference, Quality and Link Balance 190 Cells having UL interference, 24-hour/10-day breakdowns (190) 196 UL and DL quality and UL interference per TRX, 24-hour/10-day breakdowns (196) 197 UL and DL quality per TRX (197) 244 Distribution of call samples by codecs and quality classes (BER) (244) 245 Distribution of call samples by codecs and quality classes (FER) (245) 246 AMR call time and quality, dynamic time and object aggregation (246) 195 Cells by DL and UL level balance (195) 191 Cells having bad link balance (191) 208 Link balance per TRX (208) (E)GPRS 229 GPRS KPI (229) 226 (E)GPRS KPIs, enhancements from 229 (226) 235 GPRS counters (235) 275 EGPRS RLC statistics (275) 280 Dynamic Abis (280) 257 Sleeping GPRS BTSs (257) 284 Gb Over IP (284) (E)QoS 270 Quality of Service (270) 281 EQoS (281) 289 EQoS Quality Control (289) AMR 244 Distribution of call samples by codecs and quality classes (BER) (244) 245 Distribution of call samples by codecs and quality classes (FER) (245) 246 AMR call time and quality, dynamic time and object aggregation (246) 247 Transcoder failure ratio (247) 248 Codec set modification failure ratio (248) PBS 260 Position based services (260) DFCA

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276 DFCA (276) 277 DFCA Assignment Quality (277) Other BSS PM 203 Location update success ratio per BSC (203) 522 BSC ET Profile (522) 278 Wireless Priority Services PI (278) Benchmark and analysis 213 BTS Doctor. (213) BTS doctor with all selections BTS doctor with configuration and parameters BTS doctor with adjacencies or alarms BTS doctor with performance statistics 216 BTS analyser (216) BTS analyser with all or cell performance profile selection BTS analyser with configuration and parameters BTS analyser with performance statistics BTS analyser with adjacency checks or alarm statistics 290 Planning and Optimisation KPIs (290) 802 (E)GPRS Benchmark KPIs (802) 204 Network benchmark statistics (heavy, use small area, 204) 800 Quality survey (800) 205 BTS GSM KPI/PI table, dynamic object and time aggregation (205) 206 TRX level GSM KPI/PI table, dynamic object and time aggregation (206) 212 BSC doctor (212) Extra 022 Active base station alarms (022) 234 Timing advance distribution per TRX (234)

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