IDENTIFYING A BEAM FOR ACCESSING A TARGET CELL OF A WIRELESS HANOVER

• US 20190110234A1
• Filed: 12/06/2018
• Published: 04/11/2019
• Est. Priority Date: 11/04/2016
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: PEISA, Janne, DA SILVA, Icaro L. J.
• Granted Patent: US 10,484,915 B2
• Time in Patent Office: Days
• CPC Class Codes: H04W 36/0072 of resource information of target access point
• CPC Class Codes: H04W 36/0077 of access information of target access point
• CPC Class Codes: H04W 36/085 involving beams of access points
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access

Abstract

In accordance with particular embodiments, there is disclosed herein a method performed by a wireless device for handover. The method comprises receiving a first handover message from a source network node associated with a source cell. The first handover message comprises an identification of a target cell and access information associated with the target cell. The target cell is different than the source cell and comprises one or more beams. The method also includes identifying at least one beam from among the one or more beams of the target cell. The at least one beam is identified based on the identification of the target cell and the access information from the first handover message. The method further includes accessing the target cell using the identified at least one beam.

Claims

1. A method performed by a wireless device for handover, the method comprising:

receiving a first handover message from a source network node associated with a source cell, the first handover message comprising an identification of a target cell and access information associated with the target cell, wherein the target cell is different than the source cell and comprises one or more beams and the access information comprises beam related information;

identifying at least one beam from among the one or more beams of the target cell based on the identification of the target cell and the access information from the first handover message; and

accessing the target cell using the identified at least one beam.

2. The method of claim 1, wherein the target cell is associated with a second network node, the second network node being different than the source network node.

3. The method of claim 1, wherein the access information comprises Random Access Channel (RACH) information.

4. The method of claim 1, wherein the target cell has at least two beams and the access information comprises an indication of allowed beams associated with the target cell, the allowed beams comprising fewer than all of the beams of the target cell.

5. The method of claim 4, wherein the access information includes a random access preamble mapped to each of the allowed beams of the target cell.

6. The method of claim 4, wherein the access information includes common random access configuration information and dedicated random access resources for the allowed beams.

7. The method of claim 1, wherein accessing the target cell using the identified at least one beam comprises accessing the target cell using a contention based random access procedure.

8. The method of claim 1, wherein accessing the target cell using the identified at least one beam comprises accessing the target cell without first reading system information associated with the target cell.

9. A wireless device for handover comprising:

a wireless interface configured to receive a first handover message from a source network node associated with a source cell, the first handover message comprising an identification of a target cell and access information associated with the target cell, wherein the target cell is different than the source cell and comprises one or more beams;

processing circuitry configured to identify at least one beam from among the one or more beams of the target cell based on the identification of the target cell and the access information from the first handover message; and

an input and output interface configured to receive input information and provide output information;

a power source configured to provide power to the wireless interface, processing circuitry and input and output interface; and

wherein the wireless interface is further configured to access the target cell using the identified at least one beam.

10. The wireless device of claim 9, wherein the target cell is associated with a second network node, the second network node being different than the source network node.

11. The wireless device of claim 9, wherein the access information comprises Random Access Channel (RACH) information.

12. The wireless device of claim 9, wherein the target cell has at least two beams and the access information comprises an indication of allowed beams associated with the target cell, the allowed beams comprising fewer than all of the beams of the target cell.

13. The wireless device of claim 12, wherein the access information includes a random access preamble mapped to each of the allowed beams of the target cell.

14. The wireless device of claim 12, wherein the access information includes common random access configuration information and dedicated random access resources for the allowed beams.

15. The wireless device of claim 9, wherein the wireless interface configured to access the target cell using the identified at least one beam is configured to access the target cell using a contention based random access procedure.

16. The wireless device of claim 9, wherein the wireless interface configured to access the target cell using the identified at least one beam is configured to access the target cell without first reading system information associated with the target cell.

17. A wireless communication system for handover, the system comprising:

at least two network nodes;

at least one wireless device wirelessly connected to a first of the at least two network nodes;

wherein the first network node is configured to;

determine access information associated with a second of the at least two network nodes for the at least one wireless device; and

prepare the access information associated with the second network node to be transmitted to the at least one wireless device; and

wherein the at least one wireless device is configured to;

receive a handover message from the first network node, the handover message comprising an identification associated with the second network node and the access information associated with the second network node;

identify and select at least one beam from the second network node; and

access the second network node using the identified and selected at least one beam based on the access information from the handover message.

18-33. -33. (canceled)