Channel state information procedure for enhanced component carriers

• US 10,015,691 B2
• Filed: 10/14/2015
• Issued: 07/03/2018
• Est. Priority Date: 10/16/2014
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Damnjanovic, Jelena, Damnjanovic, Aleksandar, Yoo, Taesang
• Primary Examiner(s): Orgad, Edan
• Assistant Examiner(s): Shah, Saumit
• Application Number:
  US14/883,487
• Publication Number:
  US 20160112892A1
• Time in Patent Office: 993 Days
• Field of Search: None
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames

Abstract

Techniques are provided for transmitting reference signals and CSI reports within a wireless communications system using variable length downlink or uplink transmission time intervals (TTIs). CSI reference signals and CSI reports may be transmitted at times that accommodate the variable length TTIs. A UE may receive signaling that indicates when a CSI reference signal is to be transmitted, and when a CSI report is to be transmitted to a base station. CSI reporting may be performed periodically using a physical uplink control channel (PUCCH) in designated uplink symbols, may be aperiodic using a physical uplink shared channel (PUSCH), or a combination thereof. A UE may receive signaling indicating periodic CSI reporting, aperiodic CSI reporting, or both. Such signaling may be received, for example, via radio resource control (RRC) signaling or within a downlink or uplink grant.

Claims

1. A method for wireless communication, comprising:

receiving one or more downlink reference signals in a variable length downlink transmission time interval (TTI), wherein the variable length downlink TTI comprises a variable number of downlink symbols;

receiving signaling that includes a periodicity and an offset to be used for identifying when a channel state information (CSI) report is to be transmitted;

estimating CSI for at least one of the one or more downlink reference signals;

identifying at least a portion of the estimated CSI for transmission in the CSI report in a variable length uplink TTI; and

determining that an initial symbol for transmission of the CSI report is configured as a downlink symbol, wherein the identifying further comprises identifying a subsequent uplink symbol for transmission of the CSI report as a first available uplink symbol following the initial symbol.

2. The method of claim 1, wherein the receiving the one or more downlink reference signals further comprises:

receiving an uplink grant comprising a variable number of uplink symbols and an indication that the CSI report is to be transmitted on a physical uplink shared channel (PUSCH) in one or more of the uplink symbols.

3. The method of claim 1, wherein the signaling comprises radio resource control (RRC) signaling.

4. The method of claim 1, further comprising:

skipping transmitting the CSI report.

5. The method of claim 4, wherein the identifying further comprises identifying a subsequent symbol for transmission of a subsequent CSI report for a reference signal received in one or more subsequent downlink symbols.

6. The method of claim 1, further comprising:

transmitting the CSI report on one or more of a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH), wherein the transmission on the PUCCH or PUSCH is determined based on at least one of a user equipment (UE) capability, a radio resource control (RRC) configuration of the UE, or whether the UE receives an uplink UL grant to transmit PUSCH data during the variable length uplink TTI, or a combination thereof.

7. An apparatus for wireless communication, comprising:

means for receiving one or more downlink reference signals in a variable length downlink transmission time interval (TTI), wherein the variable length downlink TTI comprises a variable number of downlink symbols;

means for receiving signaling that includes a periodicity and an offset to be used for identifying when a channel state information (CSI) report is to be transmitted;

means for estimating CSI for at least one of the one or more downlink reference signals;

means for identifying at least a portion of the estimated CSI for transmission in the CSI report in a variable length uplink TTI; and

means for determining that an initial symbol for transmission of the CSI report is configured as a downlink symbol, wherein the means for identifying is operable to identify a subsequent uplink symbol for transmission of the CSI report as a first available uplink symbol following the initial symbol.

8. The apparatus of claim 7, wherein the means for receiving the one or more downlink reference signals is operable to receive an uplink grant comprising a variable number of uplink symbols and an indication that the CSI report is to be transmitted on a physical uplink shared channel (PUSCH) in one or more of the uplink symbols.

9. The apparatus of claim 7, wherein the signaling comprises radio resource control (RRC) signaling.

10. The apparatus of claim 7, further comprising:

means for skipping transmitting the CSI report.

11. The apparatus of claim 7, further comprising:

means for transmitting the CSI report on one or more of a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH), wherein the transmission on the PUCCH or PUSCH is determined based on at least one of a user equipment (UE) capability, a radio resource control (RRC) configuration of the UE, or whether the UE receives an uplink UL grant to transmit PUSCH data during the variable length uplink TTI, or a combination thereof.

12. An apparatus for wireless communication, comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory, the instructions being executable by the processor to cause the apparatus to;

receive one or more downlink reference signals in a variable length downlink transmission time interval (TTI), wherein the variable length downlink TTI comprises a variable number of downlink symbols;

receive signaling that includes a periodicity and an offset to be used for identifying when a channel state information (CSI) report is to be transmitted;

estimate CSI for at least one of the one or more downlink reference signals;

identify at least a portion of the estimated CSI for transmission in the CSI report in a variable length uplink TTI; and

determine that an initial symbol for transmission of the CSI report is configured as a downlink symbol, wherein the instructions are further executable to identify a subsequent uplink symbol for transmission of the CSI report as a first available uplink symbol following the initial symbol.

13. The apparatus of claim 12, wherein the instructions are further executable by the processor to cause the apparatus to:

receive an uplink grant comprising a variable number of uplink symbols and an indication that the CSI report is to be transmitted on a physical uplink shared channel (PUSCH) in one or more of the uplink symbols.

14. The apparatus of claim 12, wherein the signaling comprises radio resource control (RRC) signaling.

15. The apparatus of claim 12, wherein the instructions are further executable by the processor to cause the apparatus to:

skip transmitting the CSI report.

16. The apparatus of claim 12, wherein the instructions are further executable by the processor to cause the apparatus to:

identify a subsequent symbol for transmission of a subsequent CSI report for a reference signal received in one or more subsequent downlink symbol.

17. The apparatus of claim 12, wherein the instructions are further executable by the processor to cause the apparatus to:

transmit the CSI report on one or more of a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH), wherein the transmission on the PUCCH or PUSCH is determined based on at least one of a user equipment (UE) capability, a radio resource control (RRC) configuration of the UE, or whether the UE receives an uplink UL grant to transmit PUSCH data during the variable length uplink TTI, or a combination thereof.

18. A non-transitory computer-readable medium storing computer-executable code for wireless communication, the code executable to:

receive one or more downlink reference signals in a variable length downlink transmission time interval (TTI), wherein the variable length downlink TTI comprises a variable number of downlink symbols;

receive signaling that includes a periodicity and an offset to be used for identifying when a channel state information (CSI) report is to be transmitted;

estimate CSI for at least one of the one or more downlink reference signals;

identify at least a portion of the estimated CSI for transmission in the CSI report in a variable length uplink TTI; and

determine that an initial symbol for transmission of the CSI report is configured as a downlink symbol, wherein the code is further executable to identify a subsequent uplink symbol for transmission of the CSI report as a first available uplink symbol following the initial symbol.

19. The non-transitory computer-readable medium of claim 18, wherein the code is further executable to:

receive an uplink grant comprising a variable number of uplink symbols and an indication that the CSI report is to be transmitted on a physical uplink shared channel (PUSCH) in one or more of the uplink symbols.

20. The non-transitory computer-readable medium of claim 18, wherein the signaling comprises radio resource control (RRC) signaling.

21. The non-transitory computer-readable medium of claim 18, wherein the code is further executable to:

skip transmitting the CSI report.

22. The non-transitory computer-readable medium of claim 18, wherein the code is further executable to:

transmit the CSI report on one or more of a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH), wherein the transmission on the PUCCH or PUSCH is determined based on at least one of a user equipment (UE) capability, a radio resource control (RRC) configuration of the UE, or whether the UE receives an uplink UL grant to transmit PUSCH data during the variable length uplink TTI, or a combination thereof.