Techniques for channel state information reference signal (CSI-RS) transmission

1 . One or more non-transitory computer-readable media (NTCRM) having instructions, stored thereon, that when executed configure a user equipment (UE) to:

determine a frequency domain allocation for a channel state information reference signal (CSI-RS) comprising determining the frequency domain allocation as a union of resource allocations of the PDSCH and the PUSCH;

receive a downlink control information (DCI) that includes an indication of a time domain allocation for the CSI-RS; and

receive the CSI-RS according to the frequency domain allocation and the time domain allocation.

2 . The one or more NTCRM of claim 1 , wherein the DCI is to schedule the PDSCH, and wherein the frequency domain allocation for the CSI-RS is the resource allocation of the PDSCH in the frequency domain.

3 . The one or more NTCRM of claim 1 , wherein the DCI is to schedule the PUSCH, and wherein the frequency domain allocation for the CSI-RS is the resource allocation of the PUSCH in the frequency domain.

4 . The one or more NTCRM of claim 1 , wherein the DCI is included in the PDCCH, wherein the PDCCH does not schedule a PDSCH or PUSCH, and wherein the frequency domain allocation for the CSI-RS is the resource allocation of the PDCCH in the frequency domain.

5 . The one or more NTCRM of claim 1 , wherein the frequency domain allocation is a union of two or more of the resource allocations of the PDSCH, the PUSCH, and the PDCCH in the frequency domain.

6 . The one or more NTCRM of claim 1 , wherein the instructions, when executed, further configure the UE to:

determine that a target frequency domain allocation does not support a CSI-RS sequence size of the CSI-RS; and

determine the frequency domain allocation of the CSI-RS as a closest frequency domain resource allocation within the target frequency domain allocation that is supported by the CSI-RS sequence size.

7 . The one or more NTCRM of claim 1 , wherein the instructions, when executed, further configure the UE to:

determine that a target frequency domain allocation does not support a CSI-RS sequence size of the CSI-RS; and

determine the frequency domain allocation of the CSI-RS as a closest frequency domain resource allocation that overlaps with the target frequency domain allocation and is supported by the CSI-RS sequence size.

8 . The one or more NTCRM of claim 1 , wherein the CSI-RS is received within the resource allocation for the PDSCH, and wherein the instructions, when executed, are further to cause the UE to receive a demodulation reference signal (DM-RS) directly after the CSI-RS.

9 . The one or more NTCRM of claim 8 , wherein the DM-RS is received before a subsequent portion of the PDSCH; or

wherein the DM-RS is received at an end of a downlink portion of a time-division duplexing (TDD) period or at an end of the resource allocation for the PDSCH.

10 . The one or more NTCRM of claim 1 , wherein the CSI-RS is a zero-power CSI-RS, and wherein the DCI includes an offset value to indicate the time domain allocation of the CSI-RS.

11 . One or more non-transitory computer-readable media (NTCRM) having instructions, stored thereon, that when executed configure a next generation Node B (gNB) to:

encode a downlink control information (DCI) for transmission to a user equipment (UE) in a physical downlink control channel (PDCCH), wherein the DCI includes an indication of a time domain allocation for a channel state information reference signal (CSI-RS);

determine a frequency domain allocation for the CSI-RS comprising determining the frequency domain allocation as a union of resource allocations of the PDSCH and the PUSCH; and

encode the CSI-RS for transmission to the UE according to the frequency domain allocation and the time domain allocation.

12 . The one or more NTCRM of claim 11 ,

wherein the DCI is to schedule the PDSCH, and wherein the frequency domain allocation for the CSI-RS is the resource allocation of the PDSCH in the frequency domain; or

wherein the DCI is to schedule the PUSCH, and wherein the frequency domain allocation for the CSI-RS is the resource allocation of the PUSCH in the frequency domain; or

wherein the DCI is included in the PDCCH, wherein the PDCCH does not schedule a PDSCH or PUSCH, and wherein the frequency domain allocation for the CSI-RS is the resource allocation of the PDCCH in the frequency domain.

13 . The one or more NTCRM of claim 11 , wherein the frequency domain allocation is a union of two or more of the resource allocations of the PDSCH, the PUSCH, and the PDCCH in the frequency domain.

14 . The one or more NTCRM of claim 11 , wherein the instructions, when executed, further configure the gNB to:

determine that a target frequency domain allocation does not support a CSI-RS sequence size of the CSI-RS; and

determine the frequency domain allocation of the CSI-RS based on the target frequency domain allocation and the CSI-RS sequence size.

15 . The one or more NTCRM of claim 11 , wherein the CSI-RS is a zero-power CSI-RS, and wherein the DCI includes an offset value to indicate the time domain allocation of the CSI-RS.

16 . The one or more NTCRM of claim 11 , wherein the CSI-RS is transmitted within the resource allocation for the PDSCH, and wherein the instructions, when executed, further configure the gNB to encode a demodulation reference signal (DM-RS) after the CSI-RS and before any subsequent portion of the PDSCH.

17 . An apparatus to be implemented in a user equipment (UE), the apparatus comprising:

memory to store a resource allocation for a physical downlink shared channel (PDSCH); and

processor circuitry coupled to the memory, the processor circuitry to:

perform a beam measurement on a channel state information reference signal (CSI-RS) received within a frequency domain allocation determined as a union of resource allocations of the PDSCH and the PUSCH; and

perform a channel estimation on a demodulation reference signal (DM-RS) received directly after the CSI-RS.

18 . The apparatus of claim 17 , wherein the DM-RS is received before any subsequent portion of the PDSCH.

19 . The apparatus of claim 17 , wherein the DM-RS is received at an end of a downlink portion of a time-division duplexing (TDD) period or at an end of the resource allocation for the PDSCH.

20 . The apparatus of claim 17 , wherein the processor circuitry is further to decode a downlink control information (DCI) that includes an indication of a time domain allocation for the CSI-RS, wherein a frequency domain allocation of the CSI-RS is the same as the resource allocation of the PDSCH in the frequency domain.