Xn 切换流程

sequenceDiagram participant UE participant S_gNB as 源gNB participant T_gNB as 目标gNB participant AMF participant SMF participant UPF Note over S_gNB: 测量报告→决定切换 S_gNB->>T_gNB: ① Xn: Handover Request T_gNB-->>S_gNB: ② Xn: Handover Request Ack S_gNB->>UE: ③ RRC Reconfiguration Note over UE: 切换到目标小区 UE->>T_gNB: ④ RRC Reconfiguration Complete T_gNB->>AMF: ⑤ NGAP: Path Switch Request AMF->>SMF: ⑥ UpdateSMContext(路径切换) SMF->>UPF: ⑦ N4 Modification(更新N3 TEID) AMF-->>T_gNB: ⑧ Path Switch Request Ack T_gNB->>S_gNB: ⑨ Xn: UE Context Release