Method and apparatus for dynamic downlink multi-beam operations

Abstract

A method for operating a user equipment (UE) comprises receiving configuration information about a transmission configuration indicator (TCI) state indication via a downlink control information (DCI), the configuration information including a set of TCI states and information for configuring the DCI from one of a downlink (DL) DCI (DL-DCI) and a DL-TCI-DCI, wherein the DL-DCI schedules a DL physical DL shared channel (PDSCH) assignment and the DL-TCI-DCI is a dedicated DCI for TCI state indication; receiving, based on the configuration information, the configured DCI; decoding the configured DCI to obtain a TCI state update; determining a receive beam based on the TCI state update; and applying the receive beam for a reception of a DL control or a DL data.

What is claimed is: 
     
         1 . A user equipment (UE) comprising:
 a transceiver configured to:
 receive configuration information about a transmission configuration indicator (TCI) state indication via a downlink control information (DCI), the configuration information including a set of TCI states and information for configuring the DCI from one of a downlink (DL) DCI (DL-DCI) and a DL-TCI-DCI, wherein the DL-DCI schedules a DL physical DL shared channel (PDSCH) assignment and the DL-TCI-DCI is a dedicated DCI for TCI state indication; and 
 receive, based on the configuration information, the configured DCI; and 
   a processor operably coupled to the transceiver, the processor configured to:
 decode the configured DCI to obtain a TCI state update; 
 determine a receive beam based on the TCI state update; and 
 apply the receive beam for a reception of a DL control or a DL data. 
   
     
     
         2 . The UE of  claim 1 , wherein:
 a TCI state refers to at least one source reference signal (RS) with a corresponding quasi co-location (QCL) type, and the QCL type is a type of a QCL property associated with the at least one source RS; and   the beam refers to the QCL type being set to a spatial property used to receive or transmit the at least one source RS included in the TCI state update.   
     
     
         3 . The UE of  claim 1 , wherein when the configured DCI is the DL-TCI-DCI, the TCI state update is used to indicate the receive beam for the reception of both the DL control and the DL data. 
     
     
         4 . The UE of  claim 1 , wherein:
 when the configured DCI is the DL-DCI, the TCI state update is used to indicate the receive beam for the reception of the DL data, and   the receive beam for the reception of the DL control is indicated by a prior TCI state, where:
 the prior TCI state is indicated via the DL-TCI-DCI in an earlier time slot, if the earlier time slot is present, and 
 the prior TCI state is a default TCI state if the earlier time slot is not present. 
   
     
     
         5 . The UE of  claim 1 , wherein:
 the TCI state update indication is via both the DL-DCI and the DL-TCI-DCI,   a first TCI state update is via the DL-TCI-DCI and a second TCI state update is via the DL-DCI, where:
 the first TCI state update is used to indicate the receive beam for the reception of the DL control, and 
 a latest one of the first and second TCI state updates is used to indicate the receive beam for the reception of the DL data. 
   
     
     
         6 . The UE of  claim 1 , wherein the processor is further configured to:
 determine a transmit beam based on the TCI state update; and   apply the transmit beam for a transmission of an UL control or an UL data, where:
 either the transmit beam is the same as the receive beam, and the TCI state update indicates to a joint TCI state for both DL and UL, or 
 the transmit beam is separate from the receive beam, and the TCI state update indicates two separate TCI states, one for DL and another for UL. 
   
     
     
         7 . The UE of  claim 1 , wherein the configuration information includes a DCI format for the configured DCI, where the DCI format is the same for both the DL-DCI and the DL-TCI-DCI. 
     
     
         8 . A base station (BS) comprising:
 a processor configured to:
 generate configuration information about a transmission configuration indicator (TCI) state indication via a downlink control information (DCI), the configuration information including a set of TCI states and information for configuring the DCI from one of a downlink (DL) DCI (DL-DCI) and a DL-TCI-DCI, wherein the DL-DCI schedules a DL physical DL shared channel (PDSCH) assignment and the DL-TCI-DCI is a dedicated DCI for TCI state indication; and 
 generate the configured DCI that includes a TCI state update; and 
   a transceiver operably coupled to the processor, the transceiver configured to:
 transmit the configuration information; 
 transmit, based on the configuration information, the configured DCI including the TCI state update; and 
 transmit a DL control or DL data for reception by a receive beam indicated via the TCI state update. 
   
     
     
         9 . The BS of  claim 8 , wherein:
 a TCI state refers to at least one source reference signal (RS) with a corresponding quasi co-location (QCL) type, and the QCL type is a type of a QCL property associated with the at least one source RS; and   the beam refers to the QCL type being set to a spatial property used to receive or transmit the at least one source RS included in the TCI state update.   
     
     
         10 . The BS of  claim 8 , wherein when the configured DCI is the DL-TCI-DCI, the TCI state update is used to indicate the receive beam for the reception of both the DL control and the DL data. 
     
     
         11 . The BS of  claim 8 , wherein:
 when the configured DCI is the DL-DCI, the TCI state update is used to indicate the receive beam for the reception of the DL data, and   the receive beam for the reception of the DL control is indicated by a prior TCI state, where:
 the prior TCI state is indicated via the DL-TCI-DCI in an earlier time slot, if the earlier time slot is present, and 
 the prior TCI state is a default TCI state if the earlier time slot is not present. 
   
     
     
         12 . The BS of  claim 8 , wherein:
 the TCI state update indication is via both the DL-DCI and the DL-TCI-DCI,   a first TCI state update is via the DL-TCI-DCI and a second TCI state update is via the DL-DCI, where:
 the first TCI state update is used to indicate the receive beam for the reception of the DL control, and 
 a latest one of the first and second TCI state updates is used to indicate the receive beam for the reception of the DL data. 
   
     
     
         13 . The BS of  claim 8 , wherein:
 the TCI state update indicates a transmit beam to be applied for transmission of an UL control or an UL data,   where:
 either the transmit beam is the same as the receive beam, and the TCI state update indicates to a joint TCI state for both DL and UL, or 
 the transmit beam is separate from the receive beam, and the TCI state update indicates two separate TCI states, one for DL and another for UL. 
   
     
     
         14 . The BS of  claim 8 , wherein the configuration information includes a DCI format for the configured DCI, where the DCI format is the same for both the DL-DCI and the DL-TCI-DCI. 
     
     
         15 . A method for operating a user equipment (UE), the method comprising:
 receiving configuration information about a transmission configuration indicator (TCI) state indication via a downlink control information (DCI), the configuration information including a set of TCI states and information for configuring the DCI from one of a downlink (DL) DCI (DL-DCI) and a DL-TCI-DCI, wherein the DL-DCI schedules a DL physical DL shared channel (PDSCH) assignment and the DL-TCI-DCI is a dedicated DCI for TCI state indication;   receiving, based on the configuration information, the configured DCI;   decoding the configured DCI to obtain a TCI state update;   determining a receive beam based on the TCI state update; and   applying the receive beam for a reception of a DL control or a DL data.   
     
     
         16 . The method of  claim 15 , wherein:
 a TCI state refers to at least one source reference signal (RS) with a corresponding quasi co-location (QCL) type, and the QCL type is a type of a QCL property associated with the at least one source RS; and   the beam refers to the QCL type being set to a spatial property used to receive or transmit the at least one source RS included in the TCI state update.   
     
     
         17 . The method of  claim 15 , wherein when the configured DCI is the DL-TCI-DCI, the TCI state update is used to indicate the receive beam for the reception of both the DL control and the DL data. 
     
     
         18 . The method of  claim 15 , wherein:
 when the configured DCI is the DL-DCI, the TCI state update is used to indicate the receive beam for the reception of the DL data, and   the receive beam for the reception of the DL control is indicated by a prior TCI state, where:
 the prior TCI state is indicated via the DL-TCI-DCI in an earlier time slot, if the earlier time slot is present, and 
 the prior TCI state is a default TCI state if the earlier time slot is not present. 
   
     
     
         19 . The method of  claim 15 , wherein:
 the TCI state update indication is via both the DL-DCI and the DL-TCI-DCI,   a first TCI state update is via the DL-TCI-DCI and a second TCI state update is via the DL-DCI, where:
 the first TCI state update is used to indicate the receive beam for the reception of the DL control, and 
 a latest one of the first and second TCI state updates is used to indicate the receive beam for the reception of the DL data. 
   
     
     
         20 . The method of  claim 15 , further comprising:
 determining a transmit beam based on the TCI state update; and   applying the transmit beam for a transmission of an UL control or an UL data, where:
 either the transmit beam is the same as the receive beam, and the TCI state update indicates to a joint TCI state for both DL and UL, or 
 the transmit beam is separate from the receive beam, and the TCI state update indicates two separate TCI states, one for DL and another for UL.