Data transfer during mobility in layer 2 relay

Patent metadata

Field	Value
Publication number	US-12506579-B2
Application number	US-202018006772-A
Country	US
Kind code	B2
Filing date	Aug 5, 2020
Priority date	Aug 5, 2020
Publication date	Dec 23, 2025
Grant date	Dec 23, 2025

Abstract

A user equipment (UE) is configured to operate as a relay UE between a remote UE and a base station. The relay UE receives, from an originating device, a data packet for relay to a recipient device, determines that the relay of the data packet to the recipient device has failed and sends, to the originating device, a transmission including the data packet, wherein the transmission comprises an indication that the data packet is being returned to the originating device.

First claim

What is claimed:

1 . A user equipment (UE) configured to operate as a relay UE between a remote UE and a base station, comprising:
one or more processors configured to perform operations, comprising: receiving, from an originating device, a data packet for relay to a recipient device; determining that the relay of the data packet to the recipient device has failed, wherein the determining comprises detecting that a relay link has been terminated; when it is determined the relay link has been terminated, starting a timer; sending, to the originating device, a transmission including the data packet, wherein the transmission comprises an indication that the data packet is being returned to the originating device; and performing the sending operations until the timer expires; and a transceiver communicatively connected to the one or more processors.

2 . The UE of claim 1 , wherein the originating device is the base station and wherein the indication is included in an uplink (UL) Medium Access Control (MAC) header.

3 . The UE of claim 2 , wherein the UL MAC header comprises a type field and the indication is included in the type field.

4 . The UE of claim 3 , wherein the transmission is sent to the base station using one of a default data radio bearer (DRB) or a reflective DRB corresponding to a DRB used to receive the data packet.

5 . The UE of claim 2 , wherein the UL MAC header comprises a Logical Channel Identification (LCID) field and the indication comprises an identification of a pre-defined logical channel in in the LCID field.

6 . The UE of claim 5 , wherein the transmission is sent to the base station using a data radio bearer (DRB) corresponding to the pre-defined logical channel.

7 . The UE of claim 1 , wherein the originating device is the base station and wherein the indication is included in an uplink (UL) adaptation header.

8 . The UE of claim 1 , wherein determining the relay of the data packet has failed is based on, at least, not receiving an acknowledgement (ACK) from the recipient device.

9 . The UE of claim 1 , wherein the transmission comprises an original Radio Link Control (RLC) Protocol Data Unit (PDU) received from the originating device that included the data packet.

10 . The UE of claim 1 , wherein the originating device is the remote UE and wherein the indication is included in an downlink (DL) Medium Access Control (MAC) header.

11 . The UE of claim 10 , wherein the DL MAC header comprises a type field and the indication is included in the type field.

12 . The UE of claim 11 , wherein the transmission is sent to the remote UE using a default sidelink (SL) data radio bearer (DRB).

13 . The UE of claim 10 , wherein the DL MAC header comprises a Logical Channel Identification (LCID) field and the indication comprises an identification of a pre-defined logical channel in in the LCID field.

14 . The UE of claim 13 , wherein the transmission is sent to the remote UE using a sidelink (SL) data radio bearer (DRB) corresponding to the pre-defined logical channel.

15 . A baseband processor configured to perform operations comprising:
receiving, from an originating device, a data packet for relay to a recipient device; determining that the relay of the data packet to the recipient device has failed, wherein the determining comprises detecting that a relay link has been terminated; when it is determined the relay link has been terminated, starting a timer; sending, to the originating device, a transmission including the data packet, wherein the transmission comprises an indication that the data packet is being returned to the originating device, wherein the transmission comprises an original Radio Link Control (RLC) Protocol Data Unit (PDU) received from the originating device that included the data packet; and performing the sending operations until the timer expires.

16 . The baseband processor of claim 15 , wherein the originating device is a base station and wherein the indication is included in an uplink (UL) Medium Access Control (MAC) header.

17 . The baseband processor of claim 16 , wherein the UL MAC header comprises a type field and the indication is included in the type field.

18 . The baseband processor of claim 17 , wherein the transmission is sent to the base station using one of a default data radio bearer (DRB) or a reflective DRB corresponding to a DRB used to receive the data packet.

19 . A method performed by a user equipment (UE) configured to operate as a relay UE between a remote UE and a base station, comprising:
receiving, from an originating device, a data packet for relay to a recipient device; determining that the relay of the data packet to the recipient device has failed, wherein the determining comprises detecting that a relay link has been terminated; when it is determined the relay link has been terminated, starting a timer; sending, to the originating device, a transmission including the data packet, wherein the transmission comprises an indication that the data packet is being returned to the originating device, wherein the transmission comprises an original Radio Link Control (RLC) Protocol Data Unit (PDU) received from the originating device that included the data packet; and performing the sending operations until the timer expires.

Assignees

• Apple Inc

Inventors

• Chen Yuqin
• Zhang Dawei
• Xu Fangli
• Hu Haijing
• Xing Longda
• Shikari Murtaza A
• Gurumoorthy Sethuraman
• Kodali Sree Ram
• Nimmala Srinivasan
• Lovlekar Srirang A

Classifications

• H04W36/033 Primary

  in pre-organised networks · CPC title

• H04W88/04

  adapted for relaying to or from another terminal or user · CPC title

• H04W36/38

  by fixed network equipment · CPC title

• Y02D30/70

  in wireless communication networks · CPC title

• H04L5/0053 Primary

  Allocation of signalling, i.e. of overhead other than pilot signals · CPC title