Method and apparatus for channel state information feedback reporting

• US 9,912,430 B2
• Filed: 07/05/2013
• Issued: 03/06/2018
• Est. Priority Date: 07/06/2012
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Sayana, Krishna, Kim, Younsun, Lee, Hyojin, Nam, Young-Han, Han, Jin-Kyu
• Primary Examiner(s): Jiang, Charles C
• Assistant Examiner(s): ATKINS JR., GEORGE CALVIN
• Application Number:
  US13/935,711
• Publication Number:
  US 20140010126A1
• Time in Patent Office: 1,705 Days
• Field of Search: None
• CPC Class Codes: H04B 7/0456 Selection of precoding matrices or codebooks, e.g. using matrices antenna weighting
• CPC Class Codes: H04B 7/0617 for beam forming
• CPC Class Codes: H04B 7/0619 using feedback from receiving side feedback signaling for adaptive modulation/coding H04L1/0001
• CPC Class Codes: H04B 7/0626 Channel coefficients, e.g. channel state information [CSI]
• CPC Class Codes: H04J 3/1694 Allocation of channels in TDM/TDMA networks, e.g. distributed multiplexers Passive Optical Networks H04Q11/0062
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• 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: H04L 5/1469 using time-sharing

Abstract

A method for transmitting a CSI feedback report to a serving cell comprises for time division duplex, configuring at least one periodic CSI process with a CSI reference source defined by a single downlink subframe n−n_{CQI_ref}, wherein n_{CQI_ref} is a smallest value greater than or equal to a positive integer n_{CQI_ref_min}, such that it corresponds to a valid downlink subframe, wherein n_{CQI_ref_min} varies based on a number of at least one periodic CSI process. A method for CSI feedback reporting to a base station comprises configuring not to accommodate, by a user equipment, the one or more aperiodic CSI requests arrived from a serving cell except a CSI request of CSI processes with lower indexes for each serving cell, wherein a number of the one or more CSI processes with a lower index (es) is determined based on a number of pending CSI reports.

Claims

1. A method, comprising:

obtaining information on at least one channel state information (CSI) process;

receiving, at a user equipment (UE), a value on a CSI request field in an uplink downlink control information (DCI) format; and

triggering an aperiodic CSI report for a set of CSI processes in response to the value of the CSI request field based on the CSI process information,

wherein the aperiodic CSI report is based on a CSI reference resource,

wherein a CSI reference resource in a time domain for a given CSI process is defined by a downlink subframe n−

n_{CQI_ref}, wherein n_{CQI_ref} is defined based on a downlink subframe associated with the uplink DCI format, and

wherein the at least one CSI process comprises two subframe sets.

2. The method of claim 1, wherein if a number of CSI processes based on the value on the CSI request field exceeds a maximum number of CSI processes, a lowest indexed CSI process is reported.

3. The method of claim 2, wherein at least one set of CSI processes is configured at the UE.

4. The method of claim 1, wherein the n_{CQI_ref} in the time domain is defined such that the CSI reference resource is in the same valid downlink subframe as the corresponding CSI request in the uplink DCI format.

5. The method of claim 1, wherein all CSI requests other than the lowest indexed CSI process are dropped.

6. A method, comprising:

transmitting a value on a channel state information (CSI) in an uplink downlink control information (DC) format to a user equipment (UE); and

receiving an aperiodic CSI report from the UE corresponding to the value on the CSI request field,

wherein the aperiodic CSI report is based on a CSI reference resource,

wherein a CSI reference resource in a time domain is defined for a downlink subframe n−

n_{CQI_ref}, where n_{CQI_ref} is defined based on a downlink subframe associated with the uplink DCI format, and

wherein the at least one CSI process comprises two subframe sets.

7. The method of claim 6, wherein if a number of CSI processes based on the value on the CSI request field exceeds a maximum number of CSI processes, a lowest indexed CSI process is reported.

8. The method of claim 6, wherein at least one set of CSI processes is configured at.

9. The method of claim 6, wherein in the time domain is defined such that the CSI reference resource is in the same valid downlink subframe as the corresponding CSI request in the uplink DCI format.

10. The method of claim 6, wherein all CSI requests other than the lowest indexed CSI process are dropped.

11. An apparatus, comprising:

a transceiver configured to transmit signals to and receive signals from a user equipment (UE);

a controller configured to

transmit a value on a CSI request field in an uplink DCI format to the terminal, and

receive an aperiodic CSI report corresponding to the value on the CSI request field,

wherein the aperiodic CSI report is based on a CSI reference resource,

wherein a CSI reference resource in a time domain for a given CSI process is defined by a downlink subframe n−

n_{CQI_ref}, wherein n_{CQI_ref} is defined based on a downlink subframe associated with the uplink DCI format, and

wherein the at least one CSI process comprises two subframe sets.

12. The apparatus of claim 11, wherein a number of CSI processes based on the value on the CSI request field exceeds a maximum number of CSI processes, a lowest indexed CSI process is reported.

13. The apparatus of claim 11, wherein at least one set of CSI processes is configured at the UE.

14. The apparatus of claim 11, wherein the N_{CQI_ref} in the time domain is defined such that the CSI reference resource is in the same valid downlink subframe as the corresponding CSI request in the uplink DCI format.

15. The apparatus of claim 11, wherein all CSI requests other than the lowest indexed CSI process are dropped.

16. An apparatus, comprising:

a transceiver configured to transmit signals to and receive signals from a base station; and

a controller configured to

obtain information on at least one channel state information (CSI) process,

receive a value on a CSI request field in an uplink DCI format,

trigger an aperiodic CSI report for a set of CSI processes in response to the value on the CSI request field based on the information,

wherein the aperiodic CSI report is based on a CSI reference resource,

wherein a CSI reference resource in a time domain for a given CSI process is defined by a downlink subframe n−

n_{CQI_ref}, wherein n_{CQI_ref} is defined based on a downlink subframe associated with the uplink DCI format, and

wherein the at least one CSI process comprises two subframe sets.

17. The apparatus of claim 16, wherein if a number of CSI processes based on the value on the CSI request field exceeds a maximum number of CSI processes, the controller controls the transceiver to report a lowest indexed CSI process.

18. The apparatus of claim 16, wherein at least two sets of CSI processes are configured at the terminal.

19. The apparatus of claim 16, wherein the n_{CQI_ref} in the time domain is defined such that the CSI reference resource is in the same valid downlink subframe as the corresponding CSI request in the uplink DCI format.