PowerPoint Presentation

LTE RRC Connection Drop

Case 1Normal Detach request pegged as RRC Drop.RF conditions were OK, RSRP =-98.9dBm , RSRQ =-8.0 dB and normal UE Tx power further suggests there was no problem with RF.Detach request might have been sent manually and hence there was no actual drop at this point.

Case 2RRC Drop occurred on site IAL01222_2C_1 PCI 336 with EDT 2 serving from 3.5 miles. RF conditions were degraded , RSRP =-119 dBm , RSRQ=-11.94 dB , multiple measurement reports were sent however there was no response.UE power maxed out , it lost UL sync resulting in RRC Drop Case 3RRC Drop occurred on site IAL01222_2B_1 PCI 338 with EDT 2 serving from 2.3 miles. RF conditions were degraded , RSRP =-120 dBm , RSRQ=-12.69 dB , multiple measurement reports were sent however there was no response.UE kept dragging and UE power maxed out , it lost UL sync resulting in RRC Drop

Case 4

RACH failedHO commandHO initiated from site IAL02024_9A_1 PCI 273 to site IAL02024_9C_1 PCI 275.UE radiating with maximum power suggests some UL path issue even when DL RF conditions were fine.RACH failure occurred and UE couldnt access Target cell IAL02024_9C_1 PCI 275 resulting in HO failure and therefore RRC got dropped.

Case 5RRC drop pegged when UE was latched on site WIL03323_8B_1 PCI 164.Good RF conditions, RSRP=-88 dBm , RSRQ =-7dB & normal UE Tx power suggests that Drop didnt occur due to RF conditions.Drop might have occurred due to temporary UE issue or It might be a normal detach from network however can not be confirmed as L3 messages were missing for around 500ms right at the dropCase 6HO initiated from site WIL06247_7C_1 PCI 444 with EDT 3 to site WIL06288_7A_1 PCI 110 with EDT 5 serving from 12.34 miles away. Due to poor RF conditions , RACH failed and UE couldnt access site WIL06288_7A_1 PCI 110 , UE power maxed out , it lost UL Sync resulting in RRC Drop.

Case 7RRC Call drop has occurred due to handover failure between site NEL02161_2C_1 PCI 208 and NEL02147_2B_1 PCI 325 overshooting from 30 miles.Due to poor RF conditions and large distance , UE Tx power maxed out , it lost sync resulting in handover failure and RRC Drop.Need to reduce cell radius of site NEL02147_2B_1 PCI 325

Case 8RRC Call Drop has occurred due HO failure, UE latched on cell WIL03353_7A_1 PCI 342 with poor RF conditions RSRP = -120.9 dBm, RSRQ = -16.63dB at a distance from 9.14 miles away . UE initiated intra frequency HO towards target overshooter cell WIL05847_7C_1 PCI 329 however UE suddenly looses UL sync ,UE tried to RRC connection re-establishment which resulting HO failure and RRC got dropped.

Case 9At poor RF conditions, HO was initiated from site NEL01085_7A_1 PCI 204 to site NEL01005_7B_1 PCI 163 serving from 0.5 miles.UE suddenly looses sync due to poor RF quality , RSRQ