Method, user equipment, and base station for transmitting channel state information
A method, a user equipment, and a base station for transmitting channel state information (CSI) are disclosed. First, a scheduling grant command is sent by a base station. A CSI location label is obtained according to information of a resource occupied by the scheduling grant command and information of a resource occupied by a data channel that is indicated by the scheduling grant command. CSI of a carrier corresponding to the CSI location label is sent to the base station through the data channel. The CSI location label may be obtained through the scheduling grant command and the CSI of the carrier corresponding to the CSI location label may be sent or received without changing a length of an aperiodic CSI request field.
1. A method for providing aperiodic channel state information (CSI) feedback in a network utilizing carrier aggregation, the method comprising:
receiving, by a user equipment, a scheduling grant command from a base station, the scheduling grant command indicating a data channel on an uplink carrier that is to be used for uplink data communications;
determining, by the user equipment, an index identifying one downlink carrier based on an index identifying the uplink carrier, wherein the index identifying the one downlink carrier is equal to the index identifying the uplink carrier; and
sending, by the user equipment to the base station through the data channel, aperiodic CSI of the one downlink carrier, corresponding to the determined index, of a plurality of downlink carriers configured for the user equipment.
2. The method according to claim 1 , before the receiving the scheduling grant command, the method further comprising:
receiving, by the user equipment, higher layer signaling from the base station, the higher layer signaling indicating a carrier set, the carrier set comprising at least one downlink carrier of the plurality of downlink carriers configured for the user equipment, wherein the higher layer signaling specifies the at least one downlink carrier for aperiodic CSI feedback.
3. The method according to claim 1 , before the receiving the scheduling grant command, further comprising:
receiving, by the user equipment from the base station, radio resource control (RRC) signaling, wherein the RRC signaling is used for configuring the plurality of downlink carriers for the user equipment.
4. The method according to claim 3 , after receiving the RRC signaling, further comprising:
receiving, by the user equipment from the base station, media access control (MAC) signaling, wherein the MAC signaling is used for activating the one downlink carrier.
5. The method according to claim 1 , wherein the scheduling grant command is an uplink scheduling grant command comprising a CSI request field, the CSI request field indicating the user equipment to send aperiodic CSI feedback.
6. A user equipment for providing aperiodic channel state information (CSI) feedback in a network utilizing carrier aggregation, comprising:
a processor;
a receiver coupled with the processor,
wherein the receiver receives a scheduling grant command from a base station, the scheduling grant command indicating a data channel on an uplink carrier that is to be used for uplink data communications; and
a transmitter coupled to the processor, wherein
the processor determines an index identifying one downlink carrier based on an index identifying the uplink carrier, wherein the index identifying the one downlink carrier is equal to the index identifying the uplink carrier, and
the processor further causes the transmitter to send, to the base station through the data channel, aperiodic CSI of the one downlink carrier, corresponding to the determined index, of a plurality of downlink carriers configured for the user equipment.
7. The user equipment according to claim 6 , wherein the receiver is further configured to receive higher layer signaling from the base station, the higher layer signaling indicating a carrier set, the carrier set comprising at least one downlink carrier of the plurality of downlink carriers configured for the user equipment, wherein the higher layer signaling specifies the at least one downlink carrier for aperiodic CSI feedback.
8. The user equipment according to claim 6 , wherein
the receiver is further configured to receive, from the base station, radio resource control (RRC) signaling, wherein the RRC signaling is used for configuring the plurality of downlink carriers for the user equipment.
9. The user equipment according to claim 8 , wherein the receiver is further configured to receive, from the base station, media access control (MAC) signaling, wherein the MAC signaling is used for activating the one downlink carrier.
10. The user equipment according to claim 6 , wherein the scheduling grant command is an uplink scheduling grant command comprising a CSI request field, the CSI request field of the aperiodic CSI indicates the user equipment to send aperiodic CSI feedback.
11. The method according to claim 1 , wherein the index of the uplink carrier is obtained according to carrier indicator field (CIF) in the scheduling grant command.
12. The method according to claim 1 , wherein the index of the uplink carrier is obtained according to an index of a carrier for receiving the scheduling grant command.
13. The user equipment according to claim 6 , wherein the index of the uplink carrier is obtained according to carrier indicator field (CIF) in the scheduling grant command.
14. The user equipment according to claim 6 , wherein the index of the uplink carrier is obtained according to an index of a carrier for receiving the scheduling grant command.
15. An apparatus in a user equipment, comprising:
a storage medium including executable instructions; and
a processor;
wherein the executable instructions, when executed by the processor, cause the apparatus to perform the step of:
receiving a scheduling grant command from a base station, the scheduling grant command indicating a data channel on an uplink carrier that is to be used for uplink data communications; and
determining an index identifying one downlink carrier based on an index identifying the uplink carrier, wherein the index identifying the one downlink carrier is equal to the index identifying the uplink carrier; and
sending, to the base station through the data channel, aperiodic CSI of one downlink carrier, corresponding to the determined index, of a plurality of downlink carriers configured for the user equipment.
16. The apparatus according to claim 15 , wherein the executable instructions, when executed by the processor, cause the apparatus to perform the step of:
receiving higher layer signaling from the base station, the higher layer signaling indicating a carrier set, the carrier set comprising at least one downlink carrier of the plurality of downlink carriers configured for the user equipment, wherein the higher layer signaling specifies the at least one downlink carrier for aperiodic CSI feedback.
17. The apparatus according to claim 15 , wherein the executable instructions, when executed by the processor, cause the apparatus to perform the step of:
identifying the plurality of downlink carriers configured by radio resource control (RRC) signaling, the RRC signaling being used for configuring the plurality of downlink carriers for the user equipment and being received from the base station.
18. The apparatus according to claim 17 , wherein the executable instructions, when executed by the processor, cause the apparatus to perform the step of:
after receiving the RRC signaling, receiving from the base station, radio resource control (RRC) signaling, wherein the RRC signaling is used for configuring the plurality of downlink carriers for the user equipment.
19. The apparatus according to claim 15 , wherein the scheduling grant command is an uplink scheduling grant command comprising a CSI request field, the CSI request field of the aperiodic CSI indicates the user equipment to send aperiodic CSI feedback.
20. The apparatus according to claim 15 , wherein the index of the uplink carrier is obtained according to an index of a carrier for receiving the scheduling grant, and the index of the carrier for receiving the scheduling grant command is comprised in a carrier indicator field (CIF) in the scheduling grant command.