聯(lián)通GSM優(yōu)化100案例，也適用于其他運營商，精華呀
目 錄
一、掉話類......................................................................................................................................7
1、弱覆蓋掉話.........................................................................................................................7
2、跳頻參數(shù)設(shè)置錯誤導(dǎo)致高掉話.......................................................................................15
3、900 基站設(shè)備失敗掉話問題解決案例............................................................................17
4、小區(qū)重選參數(shù)設(shè)置不合理導(dǎo)致高掉話...........................................................................20
5、載頻故障引起高掉話.......................................................................................................21
6、個別載頻接錯天線導(dǎo)致高掉話.......................................................................................23
7、相鄰關(guān)系不全掉話...........................................................................................................24
8、過覆蓋掉話.......................................................................................................................26
9、掉話、單通問題處理.......................................................................................................29
10、載頻高溫問題引起掉話.................................................................................................31
11、隧道切換掉話問題處理.................................................................................................36
12、DSP 故障導(dǎo)致通話斷續(xù)問題..........................................................................................41
13、基站退服導(dǎo)致掉話.........................................................................................................42
14、干擾導(dǎo)致掉話.................................................................................................................45
15、無鄰區(qū)關(guān)系導(dǎo)致覆蓋差掉話.........................................................................................47
16、BCCH 同頻干擾導(dǎo)致掉話................................................................................................49
17、載波配置數(shù)據(jù)設(shè)置錯誤導(dǎo)致高掉話.............................................................................52
18、基站軟件故障導(dǎo)致高掉話.............................................................................................54
二、切換類....................................................................................................................................59
1、同頻同BSIC 造成切換成功率低.....................................................................................59
2、同頻干擾造成周圍鄰區(qū)切換成功率低...........................................................................61
3、基站入BSC 切換失敗.......................................................................................................62
4、越區(qū)覆蓋造成頻點干擾導(dǎo)致切換失敗...........................................................................63
5、GSM900/1800 網(wǎng)絡(luò)雙頻切換問題....................................................................................64
6、越區(qū)覆蓋導(dǎo)致高切換失敗率...........................................................................................68
7、切換關(guān)系不全造成弱覆蓋...............................................................................................71
8、鄰區(qū)關(guān)系缺失導(dǎo)致無法向較優(yōu)小區(qū)切換.......................................................................72
9、邊界小區(qū)鄰區(qū)參數(shù)錯誤導(dǎo)致跨MSC 切換失敗率高.......................................................75
10、規(guī)劃數(shù)據(jù)錯誤導(dǎo)致切換失敗率較高.............................................................................77
11、鄰區(qū)列表中同頻同BSIC 導(dǎo)致無法切換.......................................................................80
三、接入類....................................................................................................................................85
1、位置更新導(dǎo)致SDCCH 擁塞...............................................................................................85
2、載波故障導(dǎo)致用戶無法接入網(wǎng)絡(luò)...................................................................................92
3、小區(qū)重選造成用戶不在服務(wù)區(qū).......................................................................................94
4、傳輸設(shè)備出問題導(dǎo)致手機低電平條件下呼叫接入困難...............................................95
5、越區(qū)覆蓋造成信號波動、呼叫接入困難.......................................................................98
6、載頻連線錯誤導(dǎo)致不能正常占用小區(qū)信號.................................................................100
7、關(guān)于位置區(qū)邊界出現(xiàn)位置更新較頻繁的故障案例.....................................................101
8、非擁塞導(dǎo)致TCH 分配失敗分析.....................................................................................103
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9、冗余RTF 導(dǎo)致PDCH 無動態(tài)分配,使GPRS 用戶上網(wǎng)困難...........................................105
10、載波連接線松動導(dǎo)致高切入失敗...............................................................................107
11、電話短暫的不容易接通...............................................................................................109
四、通話質(zhì)量類...........................................................................................................................113
1、通話質(zhì)量差及高掉話小區(qū)分析.....................................................................................113
2、不當(dāng)?shù)那袚Q參數(shù)設(shè)置導(dǎo)致切換時話音斷續(xù).................................................................120
3、弱覆蓋質(zhì)量差.................................................................................................................121
4、受到干擾質(zhì)量差.............................................................................................................123
5、經(jīng)緯度錯誤導(dǎo)致規(guī)劃錯誤質(zhì)量差.................................................................................125
6、硬件故障導(dǎo)致質(zhì)量差.....................................................................................................127
7、同頻干擾造成通話質(zhì)差.................................................................................................129
8、無鄰區(qū)關(guān)系導(dǎo)致通話質(zhì)量差.........................................................................................131
五、干擾類..................................................................................................................................133
1、調(diào)整功控參數(shù)減低系統(tǒng)內(nèi)部干擾.................................................................................133
2、直放站干擾.....................................................................................................................135
3、強干擾問題的定位.........................................................................................................139
4、上行干擾.........................................................................................................................141
5、下行干擾.........................................................................................................................142
6、通過網(wǎng)絡(luò)性能進(jìn)行干擾判定及解決.............................................................................144
六、參數(shù)優(yōu)化類...........................................................................................................................159
1、更改功率預(yù)算切換類型解決過閑小區(qū).........................................................................159
2、t3101 設(shè)置不合理導(dǎo)致不能正常撥打電話..................................................................161
3、切換參數(shù)調(diào)整（handover_recognized_period） .....................................................163
4、最小接入信號電平的修改.............................................................................................165
5、BTS3012 基站射頻接收模式配置錯誤導(dǎo)致上下行不平衡..........................................166
6、某站搬遷后話務(wù)量變小的分析與處理.........................................................................170
7、切換時目標(biāo)小區(qū)最大物理重發(fā)次數(shù)參數(shù)調(diào)整.............................................................171
七、設(shè)備故障類...........................................................................................................................172
1、載波故障導(dǎo)致切換成功率低.........................................................................................172
2、傳輸質(zhì)量不好導(dǎo)致BSC 時鐘失鎖告警.........................................................................180
3、載波的上行接收通道故障導(dǎo)致覆蓋距離變小.............................................................181
4、基站覆蓋縮小問題處理.................................................................................................183
5、硬件問題導(dǎo)致?lián)艽螂娫捓щy.........................................................................................186
八、天饋類..................................................................................................................................188
1、天饋線錯接導(dǎo)致小區(qū)IOI 高.........................................................................................188
2、小區(qū)天線接反引起高擁塞.............................................................................................189
3、天饋接反.........................................................................................................................191
4、天線方位角與實際不符.................................................................................................194
5、天線接反.........................................................................................................................195
6、一個弱覆蓋問題的處理、調(diào)整過程.............................................................................197
7、天饋線錯接導(dǎo)致BER 高、PB 低故障............................................................................198
九、單通類..................................................................................................................................205
1、基站的下行干擾導(dǎo)致的單通.........................................................................................205
2、割接后，ET 框故障導(dǎo)致大面積單通............................................................................207
三個放一起解壓