Indicating status of forwarded data

Patent metadata

Field	Value
Publication number	US-2018317137-A1
Application number	US-201715497651-A
Country	US
Kind code	A1
Filing date	Apr 26, 2017
Priority date	Apr 26, 2017
Publication date	Nov 1, 2018
Grant date	—

Abstract

Apparatuses, methods, and systems are disclosed for indicating data status to a target base unit. One apparatus includes a transceiver that communicates with a remote unit and a processor. The processor determines to handover the remote unit to a target base unit. The processor forwards data for the remote unit to the target base unit and transmits the forwarded data to the remote unit. The processor also sends a status message to the target base unit, the status message indicating that forwarded data was successfully transmitted to the remote unit.

First claim

1 . An apparatus comprising:
a transceiver that communicates with a remote unit; a processor that: determines to handover the remote unit to a target base unit; forwards data for the remote unit to the target base unit; transmits the forwarded data to the remote unit; and sends a status message to the target base unit, the status message indicating that forwarded data was successfully transmitted to the remote unit.

2 . The apparatus of claim 1 , wherein determining to handover the remote unit to a target base unit comprises the processor determining to perform a conditional handover of the remote unit, wherein the processor further sends a condition for handover to the remote unit, wherein forwarding data for the remote unit to the target base unit and transmitting the forwarded data to the remote unit occur in response to the condition for handover not being met.

3 . The apparatus of claim 1 , wherein forwarding data for the remote unit to the target base unit comprises forwarding a plurality of packet data convergence protocol (“PDCP”) service data units (“SDUs”) to the target base unit, wherein the status message includes a bitmap indicating a delivery status of each the forwarded plurality of PDCP SDUs.

4 . The apparatus of claim 1 , wherein the processor further receives a radio link control (“RLC”) status report message from the remote unit, wherein the processor sends the status message to the target base unit in response to receiving the RLC status report message from the remote unit.

5 . The apparatus of claim 1 , wherein sending a status message to the target base unit comprises periodically sending a status message.

6 . The apparatus of claim 5 , wherein sending a status message periodically to the target base unit ends in response to ceasing transmitting the forwarded data for the remote unit.

7 . The apparatus of claim 1 , wherein the processor further:
receives uplink data from the remote unit; and forwards the uplink data to the target base unit.

8 . The apparatus of claim 7 , wherein the uplink data comprises at least one uplink packet data convergence protocol (“PDCP”) service data unit (“SDU”), wherein the processor sends an end marker to the target base unit in response to completing the forwarding of the at least one uplink PDCP SDU to the target base unit.

9 . The apparatus of claim 7 , wherein forwarding the uplink data to the target base unit comprises the processor:
determining whether the uplink data is in-sequence; delivering the uplink data to a core network in response to the uplink data being in-sequence; and forwarding the uplink data to the target base unit is response to the uplink data not being in-sequence.

10 . A method comprising:
determining to handover a served remote unit to a target base unit; forwarding data for the remote unit to the target base unit; transmitting the forwarded data to the remote unit; and sending a status message to the target base unit, the status message indicating that forwarded data was successfully transmitted to the remote unit.

11 . The method of claim 10 , wherein determining to handover the remote unit to a target base unit comprises determining to perform a conditional handover of the remote unit, wherein the method further comprises sending a condition for handover to the remote unit, wherein forwarding data for the remote unit to the target base unit and transmitting the forwarded data to the remote unit occur in response to the condition for handover not being met.

12 . The method of claim 10 , wherein forwarding data for the remote unit to the target base unit comprises forwarding a plurality of packet data convergence protocol (“PDCP”) service data units (“SDUs”) to the target base unit, wherein the status message includes a bitmap indicating a delivery status of each the forwarded plurality of PDCP SDUs.

13 . The method of claim 10 , further comprising receiving a radio link control (“RLC”) status report message from the remote unit, wherein sending the status message to the target base unit occurs in response to receiving the RLC status report message from the remote unit.

14 . The method of claim 10 , wherein sending a status message to the target base unit comprises periodically sending a status message.

15 . The method of claim 14 , wherein periodically sending a status message comprises ceasing to send a status message in response to ceasing transmitting the forwarded data to the remote unit.

16 . The method of claim 10 , further comprising:
receiving uplink data from the remote unit; and forwarding the uplink data to the target base unit.

17 . The method of claim 16 , wherein the uplink data comprises at least one uplink packet data convergence protocol (“PDCP”) service data unit (“SDU”), the method further comprising sending an end marker to the target base unit in response to completing the forwarding of the at least one uplink PDCP SDU to the target base unit.

18 . The method of claim 17 , wherein the target base unit generates a PDCP status report in response to receiving the end marker, the target base unit transmitting the PDCP status report to the remote unit.

19 . The method of claim 16 , wherein forwarding the uplink data to the target base unit comprises:
determining whether the uplink data is in-sequence; delivering the uplink data to a core network in response to the uplink data being in-sequence; and forwarding the uplink data to the target base unit is response to the uplink data not being in-sequence.

20 . An apparatus comprising:
a transceiver that communicates with a mobile communication network via a base unit; and a processor that: receives a conditional handover command from the base unit, the conditional handover command indicating a target base unit and a condition for handover; receives data from the base unit in response to the condition for handover not being met; connects to the target base unit in response to the condition for handover being met; and transmits a status report to the target base unit in response to connecting to the target base unit, the status report identifying data successfully received from the base unit prior to connecting to the target base unit.

21 . The apparatus of claim 20 , wherein transmitting the status report comprises transmitting a packet data convergence protocol (“PDCP”) status report using a PDCP control packet data unit (“PDU”).

22 . The apparatus of claim 21 , wherein transmitting the status report comprises transmitting the PDCP control PDU in a first uplink transmission to the target base unit.

23 . The apparatus of claim 20 , wherein the status report comprises a media access control (“MAC”) control element, wherein transmitting the status report comprises generating a status report indicating a packet data convergence protocol (“PDCP”) status of one or more data radio bearers (“DRBs”).

24 . The apparatus of claim 23 , wherein the MAC control element comprises an identifier for each of the one or more DRBs.

25 . The apparatus of claim 20 , wherein the status report comprises a radio resource control (“RRC”) information element, wherein transmitting the status report comprises generating a status report indicating a downlink packet data convergence protocol (“PDCP”) status of one or more data radio bearers (“DRBs”).

26 . The apparatus of claim 20 , wherein the processor further tran

Assignees

• Motorola Mobility Llc

Inventors

• Loehr Joachim
• Mallick Prateek Basu
• Kuchibhotla Ravi

Classifications

• H04W92/20

  between access points · CPC title

• H04W36/0033 Primary

  with transfer of context information · CPC title

• H04L2001/0092

  Error control systems characterised by the topology of the transmission link · CPC title

• H04L1/1614 Primary

  using bitmaps · CPC title

• H04W36/36

  by user or terminal equipment · CPC title