CSI feedback in NR-U
Systems, methods, and instrumentalities are described herein that may be used for transmission of one or more DCI, CSI-RS and/or CSI reports. A wireless transmit/receive unit (WTRU) may receive a DCI that includes information indicating two channel state information reference signal (CSI-RS) resources and four CSI reporting resources. Each CSI-RS resource may be associated with two CSI reporting resources. The WTRU may monitor a first CSI-RS resource for a CSI-RS. If the WTRU does not identify the CSI-RS in the first CSI-RS resource, the WTRU may monitor a second CSI-RS resource for the CSI-RS. The WTRU may receive the CSI-RS on the first CSI-RS resource or the second CSI-RS resource. The WTRU may determine availabilities of the first and/or the second CSI reporting resource associated with the CSI-RS resource on which the WTRU received the CSI-RS. The WTRU may transmit a CSI report on an available CSI reporting resource.
1. A wireless transmit/receive unit (WTRU) comprising:
a processor configured to:
receive, from a network, a transmission comprising information, wherein the information indicates first and second channel state information reference signal (CSI-RS) resources and first, second, third, and fourth channel state information (CSI) reporting resources, and wherein the first and second CSI reporting resources are associated with the first CSI-RS resource and the third and fourth CSI reporting resources are associated with the second CSI-RS resource;
monitor the first CSI-RS resource for a CSI-RS;
on a condition that no CSI-RS is identified in the first CSI-RS resource, monitor the second CSI-RS resource for the CSI-RS;
receive the CSI-RS on the first CSI-RS resource or the second CSI-RS resource, wherein:
on a condition that the CSI-RS is received on the first CSI-RS resource, the processor is configured to:
determine an availability of the first CSI reporting resource,
on a condition that the first CSI reporting resource is determined to be unavailable, determine an availability of the second CSI reporting resource, and
on a condition that the second CSI reporting resource is determined to be available, transmit a CSI report on the second CSI reporting resource, and
on a condition that the CSI-RS is received on the second CSI-RS resource, the processor is configured to:
determine an availability of the third CSI reporting resource,
on a condition that the third CSI reporting resource is determined to be unavailable, determine an availability of the fourth CSI reporting resource, and
on a condition that the fourth CSI reporting resource is determined to be available, transmit the CSI report on the fourth CSI reporting resource.
2. The WTRU of claim 1 , wherein the first and second CSI reporting resources are indicated in the transmission as first and second offsets relative to the first CSI-RS resource, and wherein the third and fourth CSI reporting resources are indicated in the transmission as third and fourth offsets relative to the second CSI-RS resource.
3. The WTRU of claim 1 , wherein the processor is configured to determine the availability of a CSI reporting resource by performing listen before talk (LBT) associated with the CSI reporting resource.
4. The WTRU of claim 1 , wherein the transmission comprises a downlink control information (DCI).
5. The WTRU of claim 1 , wherein on a condition that the first CSI resource is determined to be available, the processor is further configured to transmit the CSI report on the first CSI reporting resource.
6. The WTRU of claim 1 , wherein on a condition that the third CSI resource is determined to be available, the processor is further configured to transmit the CSI report on the third CSI reporting resource.
7. A method implemented in a WTRU, the method comprising:
receiving, from a network, a transmission comprising information, wherein the information indicates first and second channel state information reference signal (CSI-RS) resources and first, second, third, and fourth channel state information (CSI) reporting resources, and wherein the first and second CSI reporting resources are associated with the first CSI-RS resource and the third and fourth CSI reporting resources are associated with the second CSI-RS resource;
monitoring the first CSI-RS resource for a CSI-RS;
on a condition that no CSI-RS is identified in the first CSI-RS resource, monitoring the second CSI-RS resource for the CSI-RS;
receiving the CSI-RS on the first CSI-RS resource or the second CSI-RS resource, wherein:
on a condition that the CSI-RS is received on the first CSI-RS resource, the method further comprises:
determining an availability of the first CSI reporting resource,
on a condition that the first CSI reporting resource is determined to be unavailable, determining an availability of the second CSI reporting resource, and
on a condition that the second CSI reporting resource is determined to be available, transmitting a CSI report on the second CSI reporting resource, and
on a condition that the CSI-RS is received on the second CSI-RS resource, the method further comprises:
determining an availability of the third CSI reporting resource,
on a condition that the third CSI reporting resource is determined to be unavailable, determining an availability of the fourth CSI reporting resource, and
on a condition that the fourth CSI reporting resource is determined to be available, transmitting the CSI report on the fourth CSI reporting resource.
8. The method of claim 7 , wherein the first and second CSI reporting resources are indicated in the transmission as first and second offsets relative to the first CSI-RS resource, and wherein the third and fourth CSI reporting resources are indicated in the transmission as third and fourth offsets relative to the second CSI-RS resource.
9. The method of claim 7 , wherein determining the availability of a CSI reporting resource comprises performing listen before talk (LBT) associated with the CSI reporting resource.
10. The method of claim 7 , wherein the transmission comprises a downlink control information (DCI).
11. The method of claim 7 , wherein on a condition that the first CSI resource is determined to be available, the method further comprises transmitting the CSI report on the first CSI reporting resource.
12. The method of claim 7 , wherein on a condition that the third CSI resource is determined to be available, the method further comprises transmitting the CSI report on the third CSI reporting resource.