Apparatus, system and method to signal and execute conditional handover in a cellular network
An apparatus of a Radio Access Network (RAN) node, a system, and a method. The apparatus includes one or more processors to generate a conditional handover (CHO) execution message to a user equipment (UE), the CHO execution message including a plurality of execution conditions to trigger execution of a handover (HO) of the UE from the RAN node to a target RAN node; and causing transmission of the CHO execution message to the UE.
1. An apparatus of a New Radio (NR) Radio Access Network (RAN) node (NR gNodeB), the apparatus comprising:
a Radio Frequency (RF) circuitry interface to send and receive messages to and from a RF circuitry; and
one or more processors coupled to the RF circuitry interface, the one or more processors to:
generate a conditional handover (CHO) execution message to a user equipment (UE), the CHO execution message including a plurality of execution conditions to trigger execution of a handover (HO) of the UE from the NR gNodeB to a target NR gNodeB, wherein the plurality of execution conditions correspond to respective event identifications (IDs) to identify events to trigger execution of the HO by the UE, and wherein each of the event IDs includes one of an A3 event or an A5 event, and information on a corresponding time to trigger (TTT); and
cause transmission of the CHO execution message to the UE.
2. The apparatus of claim 1 , wherein the CHO execution message corresponds to an information element in a radio resource control (RRC) message.
3. The apparatus of claim 1 , wherein the one or more processors are further to:
process a measurement report from the UE; and
generate and cause to transmit the CHO execution message based on the measurement report.
4. The apparatus of claim 1 , further including a radio front end module coupled to the one or more processors.
5. The apparatus of claim 4 , further including one or more antennas coupled to the radio front end module, the one or more antennas configured to transmit the CHO execution message to the UE.
6. One or more non-transitory computer-readable media comprising instructions to cause an apparatus of a New Radio (NR) User Equipment (UE), upon execution of the instructions by one or more processors of the apparatus, to perform operations including:
processing a conditional handover (CHO) execution message from a NR gNodeB, the CHO execution message including a plurality of execution conditions to trigger execution of a handover (HO) of the UE from the NR gNodeB to a target NR gNodeB, wherein the plurality of execution conditions correspond to respective event identifications (IDs) to identify events to trigger execution of the HO by the UE, and wherein each of the event IDs includes one of an A3 event or an A5 event, and information on a corresponding time to trigger (TTT); and
based on the plurality of execution conditions, executing a handover (HO) process from the NR gNodeB to a target NR gNodeB.
7. The computer-readable media of claim 6 , wherein the CHO execution message corresponds to an information element in a radio resource control (RRC) message.
8. The computer-readable media of claim 6 , wherein the operations further include determining whether entering conditions of the plurality of execution conditions have been met.
9. A method to be performed by an apparatus of a New Radio (NR) radio access node (RAN) including:
generating a conditional handover (CHO) execution message to a user equipment (UE), the CHO execution message including a plurality of execution conditions to trigger execution of a handover (HO) of the UE from the RAN node to a target RAN node, wherein the plurality of execution conditions correspond to respective event identifications (IDs) to identify events to trigger execution of the HO by the UE, and wherein each of the event IDs includes one of an A3 event or an A5 event, and information on a corresponding time to trigger (TTT); and
causing transmission of the CHO execution message to the UE.
10. The method of claim 9 , wherein the CHO execution message corresponds to an information element in a radio resource control (RRC) message.
11. The method of claim 9 , wherein the method further includes:
processing a measurement report from the UE; and
generating and cause to transmit the CHO execution message based on the measurement report.
12. The method of claim 9 , further including transmitting the CHO execution message to the UE.
13. An apparatus of a New Radio (NR) Radio Access Network (RAN) node, the apparatus comprising:
means for generating a conditional handover (CHO) execution message to a user equipment (UE), the CHO execution message including a plurality of execution conditions to trigger execution of a handover (HO) of the UE from the RAN node to a target RAN node, wherein the plurality of execution conditions correspond to respective event identifications (IDs) to identify events to trigger execution of the HO by the UE, and wherein each of the event IDs includes one of an A3 event or an A5 event, and information on a corresponding time to trigger (TTT); and
means for causing transmission of the CHO execution message to the UE.
14. The apparatus of claim 13 , wherein the one or more TTTs include one of a common TTT corresponding to all event IDs or separate TTTs corresponding to respective ones of the event IDs.