Priority rules of periodic CSI reporting in carrier aggregation
A method of determining priority rules for periodic CSI reporting in carrier aggregation is proposed. A UE obtains channel state information (CSI) feedback for multiple downlink component carriers (CCs) in a multi-carrier wireless communication network. Each downlink CC is associated with a feedback mode, and each feedback mode comprises a set of feedback types to be reported to a base station at time slots configured by an upper layer. The UE then determines a prioritized downlink CC for CSI reporting based on priority levels of the feedback types to be transmitted for each downlink CC at a given time slot. The UE then transmits the corresponding CSI feedback for the prioritized downlink CC at the given time slot via a feedback channel over a primary uplink CC. In one embodiment, different feedback types are prioritized by groups, and each group has several feedback types sharing the same priority.
1. A method comprising:
obtaining channel state information (CSI) feedback for multiple downlink component carriers (CCs) by a user equipment (UE) in a multi-carrier wireless communication network, wherein each downlink CC is associated with a feedback mode, and wherein each feedback mode comprises a set of feedback types to be reported to a base station at time slots configured by an upper layer;
determining a prioritized downlink CC for CSI reporting based on feedback types and feedback modes to be transmitted for each downlink CC at a given time slot, wherein different feedback types are organized into feedback type groups based on CSI information types, wherein multiple feedback types within the same feedback type group share the same priority level, wherein different feedback modes are organized into feedback mode groups based on transmission modes, and wherein multiple feedback modes within the same feedback mode group share the same priority level; and
transmitting corresponding CSI feedback for the prioritized downlink CC over a primary uplink CC.
2. The method of claim 1 , wherein each feedback mode is semi-statically configured by the upper layer and linked to a MIMO transmission mode.
3. The method of claim 1 , wherein different feedback types are organized into the feedback type groups based on CSI information types including precoding type indicator, rank indication, channel quality indicator, precoder matrix indicator and the combinations.
4. The method of claim 1 , wherein each feedback type is periodically reported to the base station, and wherein each set of feedback types for corresponding downlink CC form complete CSI feedback information.
5. The method of claim 1 , wherein a first feedback type is supported by aperiodic reporting, wherein a second feedback type is not supported by aperiodic reporting, and wherein the first feedback type has a lower priority level than the second feedback type in periodic CSI reporting.
6. The method of claim 1 , wherein the prioritized downlink CC is further determined based on an upper layer configuration if the feedback types have the same priority level.
7. The method of claim 6 , wherein the upper link configuration includes defining a priority rule that is explicitly signaled or implicitly predefined.
8. A user equipment (UE), comprising:
a channel state information (CSI) measurement module that obtains CSI feedback for multiple downlink component carriers (CCs) by a user equipment (UE) in a multi-carrier wireless communication network, wherein each downlink CC is associated with a feedback mode, and wherein each feedback mode comprises a set of feedback types to be reported to a base station at time slots configured by an upper layer;
a periodic-CSI reporting module that determines a prioritized downlink CC for CSI reporting based on feedback types and feedback modes to be transmitted for each downlink CC at a given time slot, wherein different feedback types are organized into feedback type groups based on CSI information types, wherein multiple feedback types within the same feedback type group share the same priority level, wherein different feedback modes are organized into feedback mode groups based on transmission modes, and wherein multiple feedback modes within the same feedback mode group share the same priority level; and
a radio frequency module that transmits corresponding CSI feedback for the prioritized downlink CC over a primary uplink CC.
9. The UE of claim 8 , wherein each feedback mode is semi-statically configured by the upper layer and linked to a MIMO transmission mode.
10. The UE of claim 8 , wherein different feedback types are organized into the feedback type groups based on CSI information types including precoding type indicator, rank indication, channel quality indicator, precoder matrix indicator and the combinations.
11. The UE of claim 8 , wherein each feedback type is periodically reported to the base station, and wherein each set of feedback types for corresponding downlink CC form complete CSI feedback information.
12. The UE of claim 8 , wherein a first feedback type is supported by aperiodic reporting, wherein a second feedback type is not supported by aperiodic reporting, and wherein the first feedback type has a lower priority level than the second feedback type in periodic CSI reporting.
13. The UE of claim 8 , wherein the prioritized downlink CC is further determined based on an upper layer configuration if the feedback types have the same priority level.
14. The UE of claim 13 , wherein the upper link configuration includes defining a priority rule that is explicitly signaled or implicitly predefined.
15. A user equipment (UE), comprising:
a processor; and
a memory comprising a program that, when executed by the processor, causes the processor to perform operations comprising:
obtaining channel state information (CSI) feedback for multiple downlink component carriers (CCs) by the user equipment (UE) in a multi-carrier wireless communication network, wherein each downlink CC is associated with a feedback mode, and wherein each feedback mode comprises a set of feedback types to be reported to a base station at time slots configured by an upper layer;
determining priority rules for CSI feedback reporting based at least in part on feedback types to be transmitted for each downlink CC at a given time slot, wherein different feedback types are organized into feedback type groups based on CSI information types, wherein multiple feedback types within the same feedback type group share the same priority level, wherein different feedback modes are organized into feedback mode groups based on transmission modes, and wherein multiple feedback modes within the same feedback mode group share the same priority level; and
transmitting CSI feedback for a prioritized downlink CC using a primary uplink CC.
16. The UE of claim 15 , wherein each feedback mode is semi-statically configured by the upper layer and linked to a MIMO transmission mode.
17. The UE of claim 15 , wherein different feedback types are organized into the feedback type groups based on CSI information types including precoding type indicator, rank indication, channel quality indicator, precoder matrix indicator and the combinations.
18. The UE of claim 17 , wherein the prioritized downlink CC is determined such that each of the multiple downlink CCs has substantially equal opportunity to report CSI feedback.
19. The UE of claim 15 , wherein each feedback type is periodically reported to the base station, and wherein each set of feedback types for corresponding downlink CC form complete CSI feedback information.
20. The UE of claim 15 , wherein a first feedback type is supported by aperiodic reporting, wherein a second feedback type is not supported by aperiodic reporting, and wherein the first feedback type has a lower priority level than the second feedback type in periodic CSI reporting.
21. The UE of claim 15 , wherein the prioritized downlink CC is further determined based on an upper layer configuration if the feedback types have the same priority level.
22. The UE of claim 21 , wherein the upper link configuration includes defining a priority rule that is explicitly signaled or implicitly predefined.