METHOD AND APPARATUS FOR IMPROVING BEAM FINDING IN A WIRELESS COMMUNICATION SYSTEM

• US 20160219571A1
• Filed: 01/25/2016
• Published: 07/28/2016
• Est. Priority Date: 01/26/2015
• Status: Active Grant

• Current Assignee: ASUSTek Computer, Inc.
• Original Assignee: ASUSTek Computer, Inc.
• Inventors: Lin, Ko-Chiang, Kuo, Richard Lee-Chee
• Granted Patent: US 11,006,421 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition
• CPC Class Codes: H04W 52/04 TPC
• CPC Class Codes: H04W 72/046 the resource being in the space domain, e.g. beams
• CPC Class Codes: H04W 72/0473 the resource being transmission power
• CPC Class Codes: H04W 74/006 in the downlink, i.e. towards the terminal
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access
• CPC Class Codes: H04W 88/02 Terminal devices
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

A method and apparatus for improving beam finding in a wireless communication system. In one embodiment, the method includes the base station detecting a first preamble transmission from a UE on a beam. The method also includes the base station examining extra transmissions to detect whether there are other beams which can be used to communicate with the UE. The method further includes the base station considering a beam set of the UE is complete if a rule is fulfilled, wherein the beam set of the UE includes beam(s) through which the UE could communicate with the base station.

Claims

1. A method of a base station, comprising:

the base station detects a first preamble transmission from a UE (User Equipment) on a beam;

the base station examines extra transmissions to detect whether there are other beams which can be used to communicate with the UE; and

the base station considers a beam set of the UE is complete if a rule is fulfilled, wherein the beam set of the UE includes beam(s) through which the UE could communicate with the base station.

2. The method of claim 1, wherein the base station considers that the beam set of the UE is complete when all qualified beams of the UE have been found.

3. The method of claim 1, wherein the rule is based on a total number of extra transmissions.

4. The method of claim 1, wherein the rule is based on a number of extra transmissions after a new qualified beam has been detected.

5. The method of claim 1, wherein the rule is based on a power difference between a transmission power of the first preamble and a transmission power of an extra transmission.

6. The method of claim 1, wherein the rule is based on a quality of a newly detected beam from an extra transmission.

7. The method of claim 1, wherein the rule is based on whether a difference of strength of the newly detected beam and strength of the strongest beam reaches a certain value.

8. The method of claim 1, wherein the rule is based on whether a newly detected beam has a quality above a threshold.

9. A method of a UE (User Equipment), comprising:

the UE transmits a preamble during a random access (RA) procedure;

the UE receives a RAR (Random Access Response) from a base station after the base station detects the transmitted preamble on a beam; and

the UE performs several extra transmissions after receiving the RAR from the base station.

10. The method of claim 9, wherein the number of extra transmissions could be fixed or configurable.

11. The method of claim 9, wherein the extra transmissions could be terminated by a signaling from the base station or by another RAR from the base station.

12. A method of a UE (User Equipment), comprising:

the UE transmits a first preamble during a random access (RA) procedure;

the UE receives a RAR (Random Access Response) from a base station in response to the first preamble transmission after the base station detects the first preamble on a beam; and

the UE transmits a second preamble in response to the RAR,

wherein the power of the second preamble transmission is the power of the first preamble transmission plus a power offset.

13. The method of claim 12, wherein the power offset is different from a ramping step.

14. A method of a UE (User Equipment), comprising:

the UE transmits a first preamble transmission during a random access procedure;

the UE receives a RAR (Random Access Response) from a base station in response to the first preamble transmission after the base station detects the first preamble on a beam; and

the UE derives a transmission power for a transmission of a signal subsequent to the RAR.

15. The method of claim 14, further comprising:

the UE adds a power offset to the derived transmission power if the power offset is configured.

16. The method of claim 15, wherein the power offset is reduced from the derived transmission power if the signal has been transmitted for a certain number of times.

17. The method of claim 15, wherein the power offset is reduced from the derived transmission power if the UE receives an indication from the base station to reduce the derived transmission power.

18. The method of claim 15, wherein the power offset is applied for transmissions for beam finding or for beam tracking, and is not applied for data transmissions.

19. The method of claim 14, wherein the UE derives the transmission power based on ramping step information included in the RAR, and the ramping step information includes how many ramping steps should be reduced to derive the transmission power.

20. The method of claim 14, further comprising:

the UE is configured with two different TPC (Transmit Power Control) command ranges in RAR; and

the UE applies the configured TPC command ranges to derive the transmission power for the transmission of the signal subsequent to the receipt of the RAR.

21. The method of claim 20, wherein the different TPC command ranges are configured for different purposes of performing RA procedure.