Circuit switched fallback method and device
The present disclosure relates to a pre-5 th -Generation (5G) or 5G communication system to be provided for supporting higher data rates Beyond 4 th -Generation (4G) communication system such as Long Term Evolution (LTE). According to an embodiment of the present disclosure, a circuit switched fallback (CSFB) method is provided. The method comprising: receiving, by a first base station, a user equipment (UE) context modification request message from a mobility management entity (MME), wherein the UE context modification request message includes a CSFB indicator; receiving, by the first base station, a radio link failure (RLF) indication message from a second base station; and determining, by the first base station, whether to trigger a handover procedure.
1. A method performed by a first base station in a wireless communication system, the method comprising:
receiving, from a mobility management entity (MME), a user equipment (UE) context modification request message including a circuit switched fallback (CSFB) indicator;
receiving, from a second base station, a radio link failure (RLF) indication message; and
determining not to trigger a handover procedure based on the CSFB indicator and the RLF indication message.
2. The method of claim 1 , wherein the first base station is located in a previous serving cell of the UE, and wherein the second base station is located in a re-selected cell of the UE.
3. The method of claim 1 , wherein determining not to trigger the handover procedure causes RRC re-establishment between the UE and the second base station to fail.
4. The method of claim 1 , wherein the CSFB indicator indicates priority information of a CSFB procedure.
5. The method of claim 4 , wherein when the CSFB indicator indicates that the CSFB procedure has a high priority, the UE context modification request message further includes an additional CSFB indicator; and
wherein the additional CSFB indicator indicates whether an information element (IE) in a handover restriction list is used for the CSFB procedure having the high priority.
6. A first base station in a wireless communication system, comprising:
a transceiver configured to:
receive, from a mobility management entity (MME), a user equipment (UE) context modification request message including a circuit switched fallback (CSFB) indicator; and
receive, from a second base station, a radio link failure (RLF) indication message, and
a controller configured to determine not to trigger a handover procedure based on the CSFB indicator and the RLF indication message.
7. The first base station of claim 6 , wherein determining not to trigger the handover procedure causes RRC re-establishment between the UE and the second base station to fail.
8. The first base station of claim 6 , wherein the CSFB indicator indicates priority information of a CSFB procedure.
9. The first base station of claim 8 , wherein when the CSFB indicator indicates that the CSFB procedure has a high priority, the UE context modification request message further includes an additional CSFB indicator; and
wherein the additional CSFB indicator indicates whether an information element (IE) in a handover restriction list is used for the CSFB procedure having the high priority.
10. The first base station of claim 6 , wherein the first base station is located in a previous serving cell of the UE, and wherein the second base station is located in a re-selected cell of the UE.
11. A method performed by a first base station in a wireless communication system, the method comprising:
receiving, from a mobility management entity (MME), a user equipment (UE) context modification request message including a circuit switched fallback (CSFB) indicator;
receiving, from a second base station, a radio link failure (RLF) indication message; and
determining whether to trigger a handover procedure,
wherein the CSFB indicator indicates that a CSFB procedure has a high priority, and the UE context modification request message further includes an additional CSFB indicator, and
wherein the additional CSFB indicator indicates whether an information element (IE) in a handover restriction list is used for the CSFB procedure having the high priority.
12. The method of claim 11 , wherein the first base station is located in a previous serving cell of the UE, and wherein the second base station is located in a re-selected cell of the UE.
13. The method of claim 11 , wherein determining whether to trigger the handover procedure comprises determining not to trigger the handover procedure based on the CSFB indicator.
14. A first base station in a wireless communication system, comprising:
a transceiver; and
a processor configured to:
receive, from a mobility management entity (MME) via the transceiver, a user equipment (UE) context modification request message including a circuit switched fallback (CSFB) indicator;
receive, from a second base station via the transceiver, a radio link failure (RLF) indication message; and
determine whether to trigger a handover procedure,
wherein the CSFB indicator indicates a CSFB procedure has a high priority, and the UE context modification request message further includes an additional CSFB indicator, and
wherein the additional CSFB indicator indicates whether an information element (IE) in a handover restriction list is used for the CSFB procedure having the high priority.
15. The first base station of claim 14 , wherein the first base station is located in a previous serving cell of the UE, and wherein the second base station is located in a re-selected cell of the UE.
16. The first base station of claim 14 , wherein the processor is configured to determine not to trigger the handover procedure based on the CSFB indicator.