Paging optimizations for relay operation
Aspects relate to paging optimizations in relay operations. A remote UE may provide one or more paging identifiers identifying the remote UE to one or more relay UEs over respective relay links therebetween. Each relay UE may provide the paging identifier(s) of the remote UE to a respective serving radio access network (RAN) node, which may further provide the paging identifier(s) of the remote UE to an anchor RAN node and/or core network node to optimize paging of the remote UE. For example, paging of the remote UE may be limited to the cell(s) including the relay UE(s). The remote UE may further be configured to select to receive the paging message from one of the relay UEs or may receive the paging message from each of the relay UEs. A relay UE may further transmit a page reject message to reject a paging message.
1 . A method for wireless communication at a relay user equipment (UE) in a wireless communication network, the method comprising:
receiving, from a remote UE in wireless communication with the relay UE via a relay link, paging information comprising a paging identifier identifying the remote UE and a paging cycle of the remote UE; and
forwarding the paging identifier to a radio access network (RAN) node in wireless communication with the relay UE.
2 . The method of claim 1 , wherein the paging identifier comprises a serving temporary mobile subscriber identity (S-TMSI).
3 . The method of claim 2 , further comprising:
receiving a core network (CN)-initiated paging message for the remote UE via the RAN node when the remote UE is in an idle state, wherein the CN-initiated paging message comprises the S-TMSI; and
forwarding the CN-initiated paging message to the remote UE.
4 . The method of claim 1 , wherein the paging identifier comprises an inactive radio network temporary identifier (I-RNTI).
5 . The method of claim 4 , wherein the paging identifier further comprises an S-TMSI.
6 . The method of claim 4 , further comprising:
receiving a radio access network (RAN)-initiated paging message from the RAN node for the remote UE when the remote UE is in an inactive state, wherein the RAN-initiated paging message comprises the I-RNTI of the remote UE; and
forwarding the RAN-initiated paging message to the remote UE.
7 . The method of claim 1 , further comprising:
maintaining a list of registered remote UEs including the remote UE;
receiving a paging message from the RAN node for an additional remote UE, wherein the paging message comprises an additional paging identifier of the additional remote UE; and
transmitting a page reject message to the RAN node to reject the paging message when the list of registered remote UEs does not include the additional paging identifier of the additional remote UE.
8 . The method of claim 1 , wherein the forwarding the paging identifier to the RAN node comprises:
forwarding the paging identifier to another relay UE for forwarding of the paging identifier to the RAN node.
9 . An apparatus at a user equipment (UE) configured for wireless communication, comprising:
one or more processors; and
one or more memories coupled to the one or more processors,
wherein the one or more processors are configured to cause the UE to:
receive, from a remote UE in wireless communication with the relay UE via a relay link, paging information comprising a paging identifier identifying the remote UE and a paging cycle of the remote UE; and
forward the paging identifier to a radio access network (RAN) node in wireless communication with the relay UE.
10 . The apparatus of claim 9 , wherein the paging identifier comprises a serving temporary mobile subscriber identity (S-TMSI).
11 . The apparatus of claim 10 , wherein the one or more processors are further configured to cause the UE to:
receive a core network (CN)-initiated paging message for the remote UE via the RAN node when the remote UE is in an idle state, wherein the CN-initiated paging message comprises the S-TMSI; and
forward the CN-initiated paging message to the remote UE.
12 . The apparatus of claim 9 , wherein the paging identifier comprises an inactive radio network temporary identifier (I-RNTI).
13 . The apparatus of claim 12 , wherein the paging identifier further comprises an S-TMSI.
14 . The apparatus of claim 12 , wherein the one or more processors are further configured to cause the UE to:
receive a radio access network (RAN)-initiated paging message from the RAN node for the remote UE when the remote UE is in an inactive state, wherein the RAN-initiated paging message comprises the I-RNTI of the remote UE; and
forward the RAN-initiated paging message to the remote UE.
15 . The apparatus of claim 14 , wherein the one or more processors are further configured to cause the UE to:
determine one or more paging occasions within which to receive the RAN-initiated paging message for the remote UE based on the paging cycle of the remote UE.
16 . The apparatus of claim 9 , wherein the one or more processors are further configured to cause the UE to:
maintain a list of registered remote UEs including the remote UE;
receive a paging message from the RAN node for an additional remote UE, wherein the paging message comprises an additional paging identifier of the additional remote UE; and
transmit a page reject message to the RAN node to reject the paging message when the list of registered remote UEs does not include the additional paging identifier of the additional remote UE.
17 . The apparatus of claim 9 , wherein the one or more processors are further configured to cause the UE to:
forward the paging identifier to another relay UE for forwarding of the paging identifier to the RAN node.
18 . An apparatus at a UE, comprising:
means for receiving, from a remote UE in wireless communication with the relay UE via a relay link, paging information comprising a paging identifier identifying the remote UE and a paging cycle of the remote UE; and
means for forwarding the paging identifier to a radio access network (RAN) node in wireless communication with the relay UE.
19 . The apparatus of claim 18 , wherein the paging identifier comprises a serving temporary mobile subscriber identity (S-TMSI).
20 . The apparatus of claim 19 , further comprising:
means for receiving a core network (CN)-initiated paging message for the remote UE via the RAN node when the remote UE is in an idle state, wherein the CN-initiated paging message comprises the S-TMSI; and
means for forwarding the CN-initiated paging message to the remote UE.
21 . The apparatus of claim 18 , wherein the paging identifier comprises an inactive radio network temporary identifier (I-RNTI).
22 . The apparatus of claim 21 , wherein the paging identifier further comprises an S-TMSI.
23 . The apparatus of claim 21 , further comprising:
means for receiving a radio access network (RAN)-initiated paging message from the RAN node for the remote UE when the remote UE is in an inactive state, wherein the RAN-initiated paging message comprises the I-RNTI of the remote UE; and
means for forwarding the RAN-initiated paging message to the remote UE.
24 . The apparatus of claim 18 , further comprising:
means for maintaining a list of registered remote UEs including the remote UE;
means for receiving a paging message from the RAN node for an additional remote UE, wherein the paging message comprises an additional paging identifier of the additional remote UE; and
means for transmitting a page reject message to the RAN node to reject the paging message when the list of registered remote UEs does not include the additional paging identifier of the additional remote UE.
25 . The apparatus of claim 18 , wherein the means for forwarding the paging identifier to the RAN node comprises:
means for forwarding the paging identifier to another relay UE for forwarding of the paging identifier to the RAN node.