Role change between access points during downlink control-based handover

Patent metadata

Field	Value
Publication number	US-10939340-B2
Application number	US-201916532991-A
Country	US
Kind code	B2
Filing date	Aug 6, 2019
Priority date	Aug 9, 2018
Publication date	Mar 2, 2021
Grant date	Mar 2, 2021

Abstract

Methods and devices for performing role change are described. Dynamic signaling is used. Example formats for uplink and downlink signaling is also described. In some examples, an electronic device (ED) receives, via dynamic signaling, from a first serving cell, with which the ED initially has a primary connection, a role change trigger. The role change trigger causes the ED to use a connection with a second serving cell, with which the ED initially has a secondary connection, as the primary connection instead of the first serving cell.

First claim

The invention claimed is:

1. An electronic device (ED) comprising:
a processor configured to execute instructions to cause the ED to:
receive, via dynamic signaling, from a first serving cell, with which the ED initially has a primary connection, a role change trigger in a downlink control information (DCI) signal, the DCI signal including at least two fields containing all ‘0’ or all ‘1’, the at least two fields being at least two of: a hybrid automatic repeat request (HARQ) process field, a modulation and coding scheme (MCS) field, a new data indicator (NDI) field, or a redundancy version field;
wherein the at least two fields containing all ‘0’ or all ‘1’ are recognized as indicating the role change trigger; and
wherein the role change trigger causes the ED to use a connection with a second serving cell, with which the ED initially has a secondary connection, as the primary connection instead of the first serving cell.

2. The ED of claim 1 , wherein the instructions further cause the ED to:
transmit, to at least one of the first serving cell and the second serving cell, an acknowledgement of the role change trigger, via dynamic signaling.

3. The ED of claim 1 , wherein the ED is in connection with the first serving cell and also is in connection with the second serving cell, wherein the first serving cell is a cell of a master cell group for the ED and the second serving cell is a cell of a secondary cell group for the ED, and wherein the instructions further cause the ED to reconfigure connection information by switching configuration information between the cell of the master cell group and the cell of the secondary cell group.

4. The ED of claim 1 , wherein the DCI signal includes at least one field having no predetermined value, the at least one field being at least one of: a transmit power control (TPC) field, a physical uplink control channel (PUCCH) resource field, or a hybrid automatic repeat request (HARQ) timing field.

5. The ED of claim 4 , wherein the at least one field having no predetermined value contains information useable by the ED to provide feedback.

6. The ED of claim 1 , wherein cyclic redundancy check (CRC) bits of the DCI signal have been scrambled using a specific identifier.

7. The ED of claim 6 , wherein the specific identifier is a specific radio network temporary identifier (RNTI).

8. The ED of claim 1 , wherein the role change trigger includes information identifying the second serving cell as a target for the role change.

9. The ED of claim 1 , wherein the instructions further cause the ED to:
receive configuration information from the second serving cell; and
reconfigure connection information using the received configuration information.

10. A base station comprising:
a configured to execute instructions to cause the base station to:
determine a role change is required; and
transmit a role change trigger to an electronic device (ED) connected to a serving cell of the base station, via dynamic signaling, the role change trigger being transmitted in a downlink control information (DCI) signal, the DCI signal including at least two fields containing all ‘0’ or all ‘1’, the at least two fields being at least two of: a hybrid automatic repeat request (HARQ) process field, a modulation and coding scheme (MCS) field, a new data indicator (NDI) field, or a redundancy version field;
wherein the at least two fields containing all ‘0’ or all ‘1’ indicate the role change trigger.

11. The base station of claim 10 , wherein the instructions further cause the base station to:
receive an acknowledgement of the role change trigger from the ED, via dynamic signaling.

12. The base station of claim 10 , wherein the instructions further cause the base station to, prior to transmitting the role change trigger:
transmit a role change request to a serving cell of a second base station that is a target of the role change; and
receive a role change response from the second base station.

13. The base station of claim 10 , wherein the serving cell of the base station is initially in the role of a cell of a master cell group.

14. The base station of claim 10 , wherein the role change trigger includes information identifying a serving cell of a second base station as a target for the role change.

15. The base station of claim 10 , wherein the DCI signal includes at least one field having no predetermined value, the at least one field being at least one of: a transmit power control (TPC) field, a physical uplink control channel (PUCCH) resource field, or a hybrid automatic repeat request (HARQ) timing field; and
wherein the at least one field having no predetermined value contains a bit value for indicating a target of the role change.

16. The base station of claim 10 , wherein cyclic redundancy check (CRC) bits of the DCI signal have been scrambled using a specific radio network temporary identifier (RNTI).

17. The base station of claim 10 , wherein the role change trigger is transmitted to a group of EDs.

18. A method at an electronic device (ED), the method comprising:
receiving, via dynamic signaling, from a first serving cell, with which the ED initially has a primary connection, a role change trigger in a downlink control information (DCI) signal, the DCI signal including at least two fields containing all ‘0’ or all ‘1’, the at least two fields being at least two of: a hybrid automatic repeat request (HARQ) process field, a modulation and coding scheme (MCS) field, a new data indicator (NDI) field, or a redundancy version field;
wherein the at least two fields containing all ‘0’ or all ‘1’ are recognized as indicating the role change trigger; and
wherein the role change trigger causes the ED to use a connection with a second serving cell, with which the ED initially has a secondary connection, as the primary connection instead of the first serving cell.

19. The method of claim 18 , further comprising:
transmitting, to at least one of the first serving cell and the second serving cell, an acknowledgement of the role change trigger, via dynamic signaling.

Assignees

• Lyu Yongxia
• Zou Jialin
• Ma Jianglei
• Vilaipornsawai Usa
• Huawei Tech Co Ltd

Inventors

• Lyu Yongxia
• Zou Jialin
• Ma Jianglei
• Vilaipornsawai Usa

Classifications

• H04W72/23

  in the downlink direction of a wireless link, i.e. towards a terminal · CPC title

• H04W36/00692

  using simultaneous multiple data streams, e.g. cooperative multipoint [CoMP], carrier aggregation [CA] or multiple input multiple output [MIMO] (allocation of physical resources in CoMP or in CA H04L5/0035) · CPC title

• H04W36/08

  Reselecting an access point · CPC title

• H04W36/00837 Primary

  Determination of triggering parameters for hand-off · CPC title

• H04L1/0031 Primary

  Multiple signaling transmission (H04L1/1664, F15 take precedence) · CPC title