SYSTEM AND METHOD FOR BEAM SWITCHING AND REPORTING

• US 20170346543A1
• Filed: 04/14/2017
• Published: 11/30/2017
• Est. Priority Date: 05/26/2016
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: ISLAM, Muhammad Nazmul, SADIQ, Bilal, LUO, Tao, SUBRAMANIAN, Sundar, LI, Junyi
• Granted Patent: US 10,917,158 B2
• Time in Patent Office: Days
• CPC Class Codes: H01Q 1/245 with means for shaping the antenna pattern, e.g. in order to protect user against rf exposure
• CPC Class Codes: H04B 7/0404 the mobile station comprising multiple antennas, e.g. to provide uplink diversity
• CPC Class Codes: H04B 7/0417 Feedback systems
• CPC Class Codes: H04B 7/0452 Multi-user MIMO systems
• CPC Class Codes: H04B 7/061 using feedback from receiving side
• CPC Class Codes: H04B 7/0617 for beam forming
• CPC Class Codes: H04B 7/0623 Auxiliary parameters, e.g. power control [PCB] or not acknowledged commands [NACK], used as feedback information
• CPC Class Codes: H04B 7/0626 Channel coefficients, e.g. channel state information [CSI]
• CPC Class Codes: H04B 7/0628 Diversity capabilities
• CPC Class Codes: H04B 7/0634 Antenna weights or vector/matrix coefficients
• CPC Class Codes: H04B 7/0639 Using selective indices, e.g. of a codebook, e.g. pre-distortion matrix index [PMI] or for beam selection
• CPC Class Codes: H04B 7/0695 using beam selection
• CPC Class Codes: H04B 7/0814 based on current reception conditions, e.g. switching to different antenna when signal level is below threshold
• CPC Class Codes: H04W 16/28 using beam steering
• CPC Class Codes: H04W 28/0231 based on communication conditions dynamic wireless traffic scheduling definition based on channel quality criteria H04W72/54
• CPC Class Codes: H04W 40/248 Connectivity information update
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access
• CPC Class Codes: H04W 74/0858 collision detection

Abstract

A user equipment (UE) may be configured to perform a random access channel (RACH) procedure with a base station. As part of the RACH procedure, the base station may transmit a contention resolution message to the UE. The UE may receive, from the base station, the contention resolution message. The contention resolution message may indicate at least a beam index corresponding to a beam, such as a transmit beam of the base station. The UE may determine whether the beam index is applicable to the UE. The UE may communicate with the base station through the beam corresponding to the beam index when the beam index is applicable to the UE. For example, the UE may send an acknowledgement message to the base station, and the base station and UE may switch to a beam corresponding to the beam index after communication of the acknowledgement message.

Claims

1. A method of wireless communication by a user equipment (UE), comprising:

receiving, from a base station, a contention resolution message, the contention resolution message indicating at least a beam index corresponding to a beam;

determining whether the beam index is applicable to the UE; and

communicating with the base station through the beam corresponding to the beam index when the beam index is applicable to the UE.

2. The method of claim 1, further comprising:

transmitting, to the base station, an acknowledgement message when the beam index is determined to be applicable to the UE.

3. The method of claim 1, wherein the contention resolution message is associated with a random access procedure.

4. The method of claim 1, wherein the determining whether the beam index is applicable to the UE comprises:

attempting to decode the contention resolution message based on a radio network temporary identifier (RNTI) associated with the UE,

wherein the beam index is determined to be applicable to the UE when the contention resolution message is successfully decoded.

5. The method of claim 1, further comprising:

refraining from transmitting a non-acknowledgement message to the base station when the beam index is determined to be inapplicable to the UE or if the contention resolution message is unsuccessfully decoded.

6. The method of claim 1, wherein the contention resolution message further includes an indication of one or more channels associated with the beam index, and the communication with the base station through the beam corresponding to the beam index is performed on the one or more indicated channels.

7. The method of claim 1, further comprising;

transmitting, to the base station, a random access preamble;

receiving, from the base station, a random access response based on the random access preamble; and

transmitting, to the base station, a connection request message based on the random access response,

wherein the contention resolution message is transmitted based on the connection request message.

8. A method of wireless communication by a base station, comprising:

transmitting, to a user equipment (UE), a contention resolution message, the contention resolution message indicating at least a beam index corresponding to a beam and indicating that the beam index is applicable to the UE;

determining whether an acknowledgement message is received from the UE in response to the contention resolution message; and

communicating with the UE through the beam corresponding to the beam index when the acknowledgement message is determined to be received from the UE.

9. The method of claim 8, wherein the contention resolution message is associated with a random access procedure.

10. The method of claim 9, further comprising:

scrambling at least a portion of the contention resolution message using a radio network temporary identifier (RNTI) associated the UE.

11. The method of claim 8, wherein the contention resolution message further includes an indication of one or more channels associated with the beam index, and the communication with the UE through the beam corresponding to the beam index is performed on the one or more indicated channels.

12. The method of claim 8, further comprising:

communicating with the UE through a serving beam before transmission of the contention resolution message,

wherein the communication with the UE continues through the serving beam based on an absence of an acknowledgement message from the UE.

13. The method of claim 8, further comprising:

receiving, from the UE, a random access preamble;

transmitting, to the UE, a random access response based on the random access preamble; and

receiving, from the UE, a connection request message based on the random access response,

wherein the contention resolution message is transmitted based on the connection request message.

14. An apparatus for wireless communication, the apparatus comprising:

means for receiving, from a base station, a contention resolution message, the contention resolution message indicating at least a beam index corresponding to a beam;

means for determining whether the beam index is applicable to the apparatus; and

means for communicating with the base station through the beam corresponding to the beam index when the beam index is applicable to the apparatus.

15. The apparatus of claim 14, further comprising:

means for transmitting, to the base station, an acknowledgement message when the beam index is determined to be applicable to the apparatus.

16. The apparatus of claim 14, wherein the contention resolution message is associated with a random access procedure.

17. The apparatus of claim 14, wherein the means for determining whether the beam index is applicable to the apparatus is configured to:

attempt to decode the contention resolution message based on a radio network temporary identifier (RNTI) associated with the apparatus,

wherein the beam index is determined to be applicable to the apparatus when the contention resolution message is successfully decoded.

18. The apparatus of claim 14, further comprising:

means for refraining from transmitting a non-acknowledgement message to the base station when the beam index is determined to be inapplicable to the apparatus or if the contention resolution message is unsuccessfully decoded.

19. The apparatus of claim 14, wherein the contention resolution message further includes an indication of one or more channels associated with the beam index, and the communication with the base station through the beam corresponding to the beam index is performed on the one or more indicated channels.

20. The apparatus of claim 14, further comprising;

means for transmitting, to the base station, a random access preamble;

means for receiving, from the base station, a random access response based on the random access preamble; and

means for transmitting, to the base station, a connection request message based on the random access response,

wherein the contention resolution message is transmitted based on the connection request message.

21. An apparatus for wireless communication, the apparatus comprising:

means for transmitting, to a user equipment (UE), a contention resolution message, the contention resolution message indicating at least a beam index corresponding to a beam and indicating that the beam index is applicable to the UE;

means for determining whether an acknowledgement message is received from the UE in response to the contention resolution message; and

means for communicating with the UE through the beam corresponding to the beam index when the acknowledgement message is determined to be received from the UE.

22. The apparatus of claim 21, wherein the contention resolution message is associated with a random access procedure.

23. The apparatus of claim 22, further comprising:

means for scrambling at least a portion of the contention resolution message using a radio network temporary identifier (RNTI) associated the UE.

24. The apparatus of claim 21, wherein the contention resolution message further includes an indication of one or more channels associated with the beam index, and the communication with the UE through the beam corresponding to the beam index is performed on the one or more indicated channels.

25. The apparatus of claim 21, further comprising:

means for communicating with the UE through a serving beam before transmission of the contention resolution message,

wherein the communication with the UE continues through the serving beam based on an absence of an acknowledgement message from the UE.

26. The apparatus of claim 21, further comprising:

means for receiving, from the UE, a random access preamble;

means for transmitting, to the UE, a random access response based on the random access preamble; and

means for receiving, from the UE, a connection request message based on the random access response,

wherein the contention resolution message is transmitted based on the connection request message.

27. An apparatus for wireless communication, the apparatus comprising:

a memory; and

at least one processor coupled to the memory and configured to;

receive, from a base station, a contention resolution message, the contention resolution message indicating at least a beam index corresponding to a beam;

determine whether the beam index is applicable to the apparatus; and

communicating with the base station through the beam corresponding to the beam index when the beam index is applicable to the apparatus.

28. The apparatus of claim 27, wherein the at least one processor is further configured to:

transmit, to the base station, an acknowledgement message when the beam index is determined to be applicable to the apparatus.

29. An apparatus for wireless communication, the apparatus comprising:

a memory; and

at least one processor coupled to the memory and configured to;

transmit, to a user equipment (UE), a contention resolution message, the contention resolution message indicating at least a beam index corresponding to a beam and indicating that the beam index is applicable to the UE;

determine whether an acknowledgement message is received from the UE in response to the contention resolution message; and

communicate with the UE through the beam corresponding to the beam index when the acknowledgement message is determined to be received from the UE.

30. The apparatus of claim 29, wherein the contention resolution message is associated with a random access procedure.