CSI Reporting on PUSCH for Carrier Aggregation

• US 20110305161A1
• Filed: 06/15/2011
• Published: 12/15/2011
• Est. Priority Date: 06/15/2010
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Chen, Runhua, Onggosanusi, Eko Nugroho, Ekpenyong, Anthony Edet
• Granted Patent: US 9,762,372 B2
• Time in Patent Office: Days
• US Class Current: 370/252
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/0031 Multiple signaling transmission H04L1/1664, F15 take precedence
• 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 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0057 Physical resource allocation for CQI
• CPC Class Codes: H04L 5/0094 Indication of how sub-channels of the path are allocated
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports

Abstract

Carrier aggregation allows concurrent transmission on multiple component carriers (CC) to increase the data rate. A user equipment (UE) device in a cellular network provides periodic or aperiodic channel state information of the DL channel to a base station (eNB) for each of the aggregated CCs. The UE receives two or more reference signals corresponding to two or more aggregated CCs from an eNB. The UE computes a plurality of channel state information (CSI) reports for each of two or more aggregated CCs derived from the two or more reference signals. The UE receives a positive CSI request from the eNB for a CSI report and transmits CSI feedback to the eNB comprising one or more CSI reports selected from the plurality of CSI reports.

Claims

1. A method of operating a user equipment device in a cellular network, the method comprising:

receiving two or more reference signals corresponding to two or more aggregated component carriers (CC) at the user equipment (UE) from a base station (eNB);

computing a plurality of channel state information (CSI) estimates derived from the two or more reference signals for each of two or more aggregated CCs;

receiving a positive CSI request from the eNB for one or more CSI reports; and

transmitting CSI feedback from the UE to the eNB comprising one or more CSI reports selected from the plurality of CSI estimates.

2. The method of claim 1, further comprising receiving a bit map from the eNB that specifies a subset of the two or more CCs;

and

transmitting CSI feedback from the UE to the eNB comprising CSI reports for the CCs specified by the bit map.

3. The method of claim 1, further comprising receiving a plurality of uplink grants from the eNB for the two or more aggregated component carriers, wherein the positive CSI request is contained within only one of the plurality of uplink grants from the eNB.

4. The method of claim 1, further comprising transmitting CSI feedback from the UE to the eNB comprising CSI reports for the CCs specified by the bit map, wherein there is no associated uplink shared (UL-SCH) data on a physical uplink shared channel (PUSCH) indicated by I_MCS=29 and N_PRB≦

L, where L is a fixed number that does not vary with N_CC^DL.

5. A method of operating a base station in a cellular network, the method comprising:

transmitting two or more reference signals corresponding to two or more aggregated component carriers (CC) from the base station (eNB) to a user equipment (UE);

transmitting a positive channel state information (CSI) request to the EU for one or more CSI reports from a plurality of CSI estimates derived from the two or more reference signals by the UE for each of two or more aggregated CCs; and

receiving CSI feedback at the eNB from the UE comprising one or more CSI reports selected from the plurality of CSI estimates.

6. The method of claim 5, further comprising transmitting a bit map from the eNB that specifies a subset of the two or more CCs;

and

receiving CSI feedback at the eNB from the UE comprising CSI reports for the CCs specified by the bit map.

7. The method of claim 5, further comprising transmitting a plurality of uplink grants from the eNB to the UE for the two or more aggregated component carriers, wherein the positive CSI request is contained within only one of the plurality of uplink grants from the eNB.

8. The method of claim 5, further comprising receiving CSI feedback at the eNB from the UE comprising CSI reports for the CCs specified by the bit map, wherein there is no associated (UL-SCH) data on a physical uplink shared channel (PUSCH) indicated by I_MCS=29 and N_PRB≦

L, where L is a fixed number that does not vary with N_CC^DL.

9. A user equipment device for use in a cellular network, the device comprising:

circuitry for receiving two or more reference signals corresponding to two or more aggregated component carriers (CC) transmitted from a base station (eNB) for reception by the user equipment (UE);

circuitry for transmitting channel state information (CSI) feedback from the UE to the eNB comprising one or more CSI reports selected from a plurality of CSI estimates in response to a positive CSI request received from the eNB for one or more CSI reports; and

a processor coupled to the circuitry for transmitting and to the circuitry for receiving, the processor configured to compute a plurality of CSI estimates derived from the two or more reference signals for each of two or more aggregated CCs.

10. The device of claim 9, wherein the processor is further configured to:

receive a bit map from the eNB that specifies a subset of the two or more CCs; and

select CSI estimates for the CCs specified by the bit map for transmission of CSI feedback to the eNB.

11. The device of claim 10, wherein there is no associated uplink shared (UL-SCH) data on a physical uplink shared channel (PUSCH) indicated by I_MCS=29 and N_PRB≦

L, where L is a fixed number that does not vary with N_CC^DL.

12. The device of claim 9, wherein the processor is further configured to receive a plurality of uplink grants from the eNB for the two or more aggregated component carriers, wherein the positive CSI request is contained within only one of the plurality of uplink grants from the eNB.