Two-stage downlink control information configurations for beam operation
A method of communicating downlink control information (DCI) from a transmit/receipt point (TRP) to a user equipment (UE) is disclosed. The method includes transmitting a first stage DCI and a reference signal (RS) by a coarse beam; transmitting a second stage DCI by a refine beam; where the first stage DCI includes information of the second stage DCI.
1. A method of communicating downlink control information (DCI) from a transmit/receipt point (TRP) to a user equipment (UE), the method comprising:
transmitting a first stage DCI and a reference signal (RS) by a coarse beam, the first stage DCI comprising a first portion of control information in the DCI;
transmitting a second stage DCI by a refine beam, the second stage DCI comprising a second remaining portion of the control information in the DCI;
wherein the first stage DCI includes information identifying the second stage DCI.
2. The method of claim 1 , wherein the second stage DCI includes one of beam-specific second stage DCI and UE-specific second stage DCI.
3. The method of claim 1 , wherein the first stage DCI contains the refine beam information for receiving the second stage DCI.
4. The method of claim 1 , wherein the first stage DCI includes at least one of:
(a) a beam index;
(b) a number of antenna ports for refine beams;
(c) a configuration of the second stage DCI, wherein:
when the second stage DCI is beam-specific, the first stage DCI contains the information of the refine beam;
when the second stage DCI is UE-specific, the first stage DCI contains a specific refine beam index and resource allocation for the specific refine beam.
5. The method of claim 1 , wherein the second stage DCI comprises beam-specific second stage DCI that contains at least one of:
(a) a number of serving UEs;
(b) a Channel State Information (CSI) reference signal (RS) configuration and resource allocation information for data channel for each UE, the CSI RS configuration having CSI RS resource and quasi co-location (QCL) information.
6. The method of claim 1 , wherein the first stage DCI includes broadcast information.
7. The method of claim 6 , wherein the broadcast information includes time critical information.
8. A method for coordinated multi-point (CoMP) transmission/reception operation among a first transmit/receipt point (TRP), a second TRP, and a user equipment (UE), the method comprising:
measuring a first reference signal precoded with a first stage downlink control information (DCI) in a coarse beam from the second TRP, the first stage DCI comprising a first portion of control information in the DCI;
measuring a second reference signal precoded with a second stage DCI in a refine beam from the second TRP, the second stage DCI comprising a second remaining portion of the control information in the DCI;
performing the CoMP transmission/reception operation based on a measurement report of the second reference signal in the refine beam;
wherein the first stage DCI precoded by the coarse beam from the second TRP includes information identifying the second stage DCI precoded by the refine beam from the second TRP.
9. The method of claim 8 , wherein the CoMP transmission/reception operation is a joint transmission (JT) of the first TRP and the second TRP to the UE.
10. The method of claim 9 , further comprising:
receiving data, by the UE, from a refine beam from the first TRP and the refine beam from the second TRP in the same resource;
monitoring, by the UE, interference between the refine beam from the first TRP and the refine beam from the second TRP by detecting a third reference signal precoded with a second stage DCI of the refine beam from the first TRP, and the second reference signal precoded with the second stage DCI of the refine beam from the second TRP.
11. The method of claim 9 , wherein the UE further detects a first stage DCI and a second stage DCI from the first TRP, and monitors a coarse beam reference signal in the first stage DCI and a refine beam reference signal in the second stage DCI from the first TRP.
12. The method of claim 11 , wherein the UE further monitors the refine beam reference signal in the second stage DCI of the refine beam from the second TRP.
13. The method of claim 9 , wherein the second stage DCI from the second TRP is a beam-specific second stage DCI.
14. The method of claim 9 , wherein the second stage DCI from the second TRP is a UE-specific second stage DCI.
15. The method of claim 14 , further comprising:
receiving data, by the UE, from a refine beam from the first TRP and the refine beam from the second TRP in the same resource;
monitoring, by the UE, interference from the second TRP by configuring Channel State Information Interference Measurement (CSI-IM) for the UE, without a need to detect the second reference signal precoded with the second stage DCI of the refine beam from the second TRP.
16. The method of claim 8 , wherein the CoMP transmission/reception operation includes the UE receiving transmission from the first TRP and the second TRP using Dynamic Transceiver Switch (DTS).
17. The method of claim 16 , wherein, during the DTS, the UE monitors beam quality from the first TRP and the second TRP by detecting a third reference signal precoded with a second stage DCI of a refine beam from the first TRP, and the second reference signal precoded with the second stage DCI of the refine beam from the second TRP.
18. The method of claim 17 , wherein the second stage DCI of the refine beam from the second TRP is a beam-specific second stage DCI.
19. The method of claim 18 , wherein the UE further monitors a coarse beam reference signal in the first stage DCI and a refine beam reference signal in the second stage DCI from both the first and second TRPs.
20. The method of claim 16 , wherein the second stage DCI from the second TRP is a UE-specific second stage DCI.
21. The method of claim 20 , further comprising:
receiving data, by the UE, from the refine beam from the first TRP or the refine beam from the second TRP;
monitoring, by the UE, data channel quality in the first TRP and the second TRP, and transmitting CSI-RS measurement reports to the first TRP.
22. The method of claim 8 , wherein the CoMP transmission/reception operation includes the UE receiving transmission from the first TRP and the second TRP using Coordinated Schedule and Coordinated Beamforming (CS/CB).
23. The method of claim 22 , wherein the UE monitors a coarse beam reference signal precoded with a first stage DCI and a refine beam reference signal precoded with a second stage DCI from the first TRP, and sends a refine beam reference measurement report to the first TRP.
24. The method of claim 23 , wherein the second stage DCI from the second TRP is a beam-specific second stage DCI.
25. The method of claim 24 , wherein the second TRP allocates the refine beam second stage DCI to the same resource location as the refine beam second stage DCI of the first TRP.
26. The method of claim 24 , wherein the UE monitors beam quality from the first TRP by detecting reference signals precoded with the first stage DCI and the second stage DCI from the first TRP, and transmits measurement reports to the first TRP.
27. The method of claim 22 , wherein the second stage DCI from the second TRP is a UE-specific second stage DCI.
28. The method of claim 27 , wherein the UE monitors interference from the second TRP, beam quality from the first TRP by detecting CSI-RS data channel, and transmits CSI-RS measurement reports to the first TRP.