Channel information feedback method, user equipment, method for sending data, and base station

• US 9,755,806 B2
• Filed: 07/30/2012
• Issued: 09/05/2017
• Est. Priority Date: 08/22/2011
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Cui, Qimei, Wang, Hui, Tao, Xiaofeng, Yang, Shan, Li, Xiaona, Li, Shiyuan
• Primary Examiner(s): Duong, Christine
• Application Number:
  US14/238,560
• Publication Number:
  US 20140211653A1
• Time in Patent Office: 1,863 Days
• Field of Search: None
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 5/0035 Resource allocation in a cooperative multipoint environment
• CPC Class Codes: H04L 5/0057 Physical resource allocation for CQI
• CPC Class Codes: H04W 24/08 Testing, supervising or monitoring using real traffic
• CPC Class Codes: H04W 72/27 between access points
• CPC Class Codes: H04W 72/542 using measured or perceived quality

Abstract

A method and system for feeding back channel information to coordinated cells, the method including: measuring channel qualities of downlink channels between coordinated cells and user equipment; classifying the coordinated cells into different coordinated cell classes according to the measured channel qualities; based on different channel quality intervals corresponding to different coordinated cell classes, respectively selecting channel information feedback modes with different feedback enhancement degrees for different coordinated cell classes; and using the selected channel information feedback modes with different feedback enhancement degrees to determine the channel information to be fed back to the coordinated cells in each coordinated cell class according to a pre-determined order, and sending the determined channel information to the coordinated cells.

Claims

1. A method of feeding back channel information to coordinated cells, comprising:

measuring channel quality of downlink channels between the coordinated cells and a user equipment;

classifying the coordinated cells into different coordinated cell classes based on a measurement result of the channel quality;

selecting, based on different channel quality intervals corresponding to the different coordinated cell classes, channel information feedback modes with different levels of feedback enhancement for the different coordinated cell classes, respectively; and

determining channel information to be fed back to coordinated cells in respective coordinated cell classes in a predetermined order with use of the selected channel information feedback modes with different levels of feedback enhancement, and transmitting the determined channel information to the coordinated cells, wherein

the channel information feedback modes indicate contents of the channel information to be fed back and/or calculation manners for calculating the channel information to be fed back,

the channel information to be fed back is at least one of effective channel quantization information and phase correction angle information, and

the calculation manners are one of the following;

jointly optimizing both the effective channel quantization information and the phase correction angle information simultaneously; and

calculating the effective channel quantization information independently, and then jointly calculating the phase correction angle information based on the calculated effective channel quantization information.

2. The method according to claim 1, wherein the step of determining comprises:

determining channel information to be fed back to coordinated cells in respective coordinated cell classes corresponding to the different channel quality intervals, in a descending order of the channel quality of the different channel quality intervals.

3. The method according to claim 2, wherein the step of determining further comprises:

determining channel information to be fed back to coordinated cells in a second coordinated cell class with use of determined channel information to be fed back to coordinated cells in a first coordinated cell classes, wherein channel quality of the first coordinated cell class is higher than channel quality of the second coordinated cell class.

7. A method of transmitting data to a user equipment in coordinated cells, comprising:

transmitting measurement parameters to the user equipment;

receiving channel information fed back by the user equipment to the coordinated cells using the channel information feedback method of claim 1 after receiving the measurement parameters; and

calculating a pre-coding matrix using the channel information and transmitting the data to the user equipment with the pre-coding matrix.

8. A base station of transmitting data to a user equipment in coordinated cells, comprising:

a transmission processing circuitry configured to transmit measurement parameters to the user equipment;

a reception processing circuitry configured to receive channel information fed back by the user equipment to the coordinated cells using the channel information feedback method of claim 1 after receiving the measurement parameters; and

a calculation processing circuitry configured to calculate a pre-coding matrix using the channel information and transmit the data to the user equipment with the pre-coding matrix.

9. A wireless communication method comprising:

transmitting, by base stations in coordinated cells, measurement parameters to a user equipment;

feeding back, by the user equipment, channel information to the coordinated cells using the channel information feedback method of claim 1 after receiving the measurement parameter; and

calculating, by the base stations in the coordinated cells, after receiving the channel information, a pre-coding matrix using the channel information, and transmitting data to the user equipment with the pre-coding matrix.

10. A wireless communication system, comprising:

base stations in coordinated cells; and

a user equipment,

wherein the base stations transmit measurement parameters to the user equipment, receive channel information fed back by the user equipment, calculate a pre-coding matrix using the channel information and transmit data to the user equipment with the pre-coding matrix; and

the user equipment feeds back the channel information to the coordinated cells using the channel information feedback method of claim 1 after receiving the measurement parameters.

11. A non-transitory computer readable storage medium, comprising machine readable program codes which when being executed on an information processing machine, allow the information processing machine to execute the method in claim 1.

12. A non-transitory computer readable storage medium, comprising machine readable program codes which when being executed on an information processing machine, allow the information processing machine to execute the method in claim 7.

13. The method according to claim 1, wherein the step of selecting comprises:

selecting a channel information feedback mode with a higher level of feedback enhancement for a coordinated cell class corresponding to a channel quality interval with higher channel quality, while selecting a channel information feedback mode with a lower level of feedback enhancement for a coordinated cell class corresponding to a channel quality interval with lower channel quality.

4. A user equipment of feeding back channel information to coordinated cells, comprising:

a measurement processing circuitry configured to measure channel quality of downlink channels between the coordinated cells and a user equipment;

a classification processing circuitry configured to classify the coordinated cells into different coordinated cell classes based on a measurement result of the channel quality;

a selection processing circuitry configured to select, based on different channel quality intervals corresponding to the different coordinated cell classes, channel information feedback modes with different levels of feedback enhancement for the different coordinated cell classes, respectively; and

a determination processing circuitry configured to determine channel information to be fed back to coordinated cells in respective coordinated cell classes in a predetermined order with use of the selected channel information feedback modes with different levels of feedback enhancement, and transmit the determined channel information to the coordinated cells, wherein

the channel information feedback modes indicate contents of the channel information to be fed back and/or calculation manners for calculating the channel information to be fed back,

the channel information to be fed back is at least one of effective channel quantization information and phase correction angle information, and

the calculation manners are one of the following;

jointly optimizing the effective channel quantization information and the phase correction angle information simultaneously; and

calculating the effective channel quantization information independently, and then jointly calculating the phase correction angle information based on the calculated effective channel quantization information.

5. The user equipment according to claim 4, wherein the determination processing circuitry is further configured to:

determine channel information to be fed back to coordinated cells in respective coordinated cell classes corresponding to the different channel quality intervals, in a descending order of the channel quality of the different channel quality intervals.

6. The user equipment according to claim 5, wherein the determination processing circuitry is further configured to:

determine channel information to be fed back to coordinated cells in a second coordinated cell class with use of determined channel information to be fed back to coordinated cells in a first coordinated cell classes, wherein channel quality of the first coordinated cell class is higher than channel quality of the second coordinated cell class.

14. The user equipment according to claim 4, wherein the selection processing circuitry is further configured to:

select a channel information feedback mode with a higher level of feedback enhancement for a coordinated cell class corresponding to a channel quality interval with higher channel quality, while select a channel information feedback mode with a lower level of feedback enhancement for a coordinated cell class corresponding to a channel quality interval with lower channel quality.