Transmission of phase tracking reference signals (PT-RS)

1. A user equipment (UE) operable to receive one or more phase tracking reference signals (PT-RS) from a base station in a wireless network, the UE comprising:

one or more processors configured to:

decode, at the UE, control signaling received in a downlink from the base station, wherein the control signaling indicates a resource mapping pattern for the one or more PT-RS;

select, at the UE, the resource mapping pattern for the one or more PT-RS from a set of resource mapping patterns that are predefined at the UE, wherein the resource mapping pattern for the one or more PT-RS is selected based on the control signaling received from the base station; and

receive, at the UE, the one or more PT-RS in accordance with the resource mapping pattern for the one or more PT-RS; and

a memory interface configured to send to a memory the resource mapping pattern for the one or more PT-RS.

2. The UE of claim 1 , wherein the set of resource mapping patterns is predefined at the UE via higher layer signaling.

3. The UE of claim 1 , wherein the control signaling is received via downlink control information (DCI), wherein the DCI includes a value to indicate the resource mapping pattern for the PT-RS.

4. The UE of claim 1 , wherein the resource mapping pattern for the one or more PT-RS is based on one or more of: a modulation and coding scheme (MCS) utilized at the UE, an allocated bandwidth, a subcarrier spacing and a phase noise characteristic.

5. The UE of claim 1 , wherein a subcarrier offset of the resource mapping pattern of the one or more PT-RS is based on a cell identity (ID) or a virtual cell ID.

6. The UE of claim 1 , wherein different resource mapping patterns of the set of resource mapping patterns correspond to different time and frequency densities for corresponding PT-RS.

7. The UE of claim 1 , wherein the resource mapping pattern for the one or more PT-RS is for one antenna port and spans one subcarrier every N physical resource blocks (PRBs), wherein N is an integer that is semi-statically or dynamically adjusted according to one of a UE capability and a use case, and wherein the use case is dependent on one or more of: a modulation and coding schemes (MCS), an allocated bandwidth or a subcarrier spacing.

8. The UE of claim 1 , wherein the resource mapping pattern for the one or more PT-RS is indicated according to an adaptive pattern method wherein the resource mapping pattern for the one or more PT-RS is indicated by the base station based on one of a presence of a phase noise limited scenario in the wireless network and a noise and carrier frequency offset (CFO) limited scenario in the wireless network, wherein the phase noise limited scenario indicates that phase noise is a dominant factor affecting the wireless network, and wherein the CFO limited scenario indicates that CFO is a dominant factor affecting the wireless network.

9. A method of a user equipment (UE) operable to receive one or more phase tracking reference signals (PT-RS) from a base station in a wireless network, the method comprising:

decoding, at the UE, control signaling received in a downlink from the base station, wherein the control signaling indicates a resource mapping pattern for the one or more PT-RS;

selecting, at the UE, the resource mapping pattern for the one or more PT-RS from a set of resource mapping patterns that are predefined at the UE, wherein the resource mapping pattern for the one or more PT-RS is selected based on the control signaling received from the base station; and

receiving, at the UE, the one or more PT-RS in accordance with the resource mapping pattern for the one or more PT-RS.

10. The method of claim 9 , wherein the set of resource mapping patterns is predefined at the UE via higher layer signaling.

11. The method of claim 9 , wherein the control signaling is received via downlink control information (DCI), wherein the DCI includes a value to indicate the resource mapping pattern for the PT-RS.

12. The method of claim 9 , wherein the resource mapping pattern for the one or more PT-RS is based on one or more of: a modulation and coding scheme (MCS) utilized at the UE, an allocated bandwidth, a subcarrier spacing and a phase noise characteristic.

13. The method of claim 9 , wherein a subcarrier offset of the resource mapping pattern of the one or more PT-RS is based on a cell identity (ID) or a virtual cell ID.

14. The method of claim 9 , wherein different resource mapping patterns of the set of resource mapping patterns correspond to different time and frequency densities for corresponding PT-RS.

15. The method of claim 9 , wherein the resource mapping pattern for the one or more PT-RS is for one antenna port and spans one subcarrier every N physical resource blocks (PRBs), wherein N is an integer that is semi-statically or dynamically adjusted according to one of a UE capability and a use case, and wherein the use case is dependent on one or more of: a modulation and coding schemes (MCS), an allocated bandwidth or a subcarrier spacing.

16. The method of claim 9 , wherein the resource mapping pattern for the one or more PT-RS is indicated according to an adaptive pattern method, wherein the resource mapping pattern for the one or more PT-RS is indicated by the base station based on one of a presence of a phase noise limited scenario in the wireless network and a noise and carrier frequency offset (CFO) limited scenario in the wireless network, wherein the phase noise limited scenario indicates that phase noise is a dominant factor affecting the wireless network, and wherein the CFO limited scenario indicates that CFO is a dominant factor affecting the wireless network.