Method and apparatus for configuring default beam in communication system
The disclosure relates to a 5G or 6G communication system for supporting a higher data transmission rate. In a method performed by a UE in the communication system, the UE receives, from a base station, an RRC message including PDSCH resource allocation information and TCI information; receives, from the base station, DCI for scheduling at least one PDSCH through a first PDCCH; and receives, from the base station, data through the at least one PDSCH. In case that TCI information related to the at least one PDSCH is different from TCI information related to a second PDCCH overlapping the at least one PDSCH in a time domain and a beam switching time is required between the at least one PDSCH and the second PDCCH, the UE does not expect the second PDCCH to be searched in a region overlapping with the at least one PDSCH.
1 . A method performed by a user equipment (UE) in a communication system, the method comprising:
receiving, from a base station, a radio resource control (RRC) message including physical downlink shared channel (PDSCH) resource allocation information, transmission configuration indication (TCI) state information, and time duration information related to quasi co location (QCL);
receiving, from the base station, downlink control information (DCI) for scheduling multiple PDSCHs on a first physical downlink control channel (PDCCH);
configuring a first TCI state of PDSCHs within a time duration for QCL as a default TCI state based on a time offset between the first PDCCH and a first PDSCH of the multiple PDSCHs being less than the time duration for QCL;
receiving, from the base station, the multiple PDSCHs scheduled by the DCI;
determining whether to skip monitoring a second PDCCH overlapping with at least one PDSCH within the time duration;
in case that a second TCI state of the second PDCCH is same as the first TCI state, monitoring the second PDCCH; and
in case that the second TCI state of the second PDCCH is different from the first TCI state and a beam switching time is considered for switching a beam between the at least one PDSCH and the second PDCCH, determining to skip monitoring the second PDCCH,
wherein in case that the second PDCCH is associated with a common search space, rate matching or puncturing is performed on the at least one PDSCH overlapping the second PDCCH, and
wherein in case that the second PDCCH is associated with a UE-specific search space, the at least one PDSCH overlapping the seco d s received.
2 . The method of claim 1 , wherein a maximum number of PDCCH candidates or a maximum number of control channel elements (CCEs) of the UE is changed based on at least one symbol overlapping with the at least one PDSCH, and
wherein the maximum number of PDCCH candidates or the maximum number of CCEs is defined for each slot or each span based on a UE capability.
3 . A method performed by a base station in a communication system, the method comprising:
transmitting, to a user equipment (UE), a radio resource control (RRC) message including physical downlink shared channel (PDSCH) resource allocation information, transmission configuration indication (TCI) state information, and time duration information related to quasi co location (QCL);
transmitting, to the UE, downlink control information (DCI) for scheduling multiple PDSCHs on a first physical downlink control channel (PDCCH); and
transmitting, to the UE, the multiple PDSCHs scheduled by the DCI,
wherein, based on a time offset between the first PDCCH and a first PDSCH of the multiple PDSCHs being less than a time duration for QCL, a first TCI state of PDSCHs within the time duration for QCL is set as a default TCI state,
wherein in case that a second TCI state of a second PDCCH overlapping with at least one PDSCH within the time duration is same as the first TCI state, the second PDCCH is monitored,
wherein in case that the second TCI state of the second PDCCH is different from the first TCI state and a beam switching time is considered for switching a beam between the at least one PDSCH and the second PDCCH, monitoring the second PDCCH is skipped,
wherein in case that the second PDCCH is associated with a common search space, rate matching or puncturing is performed on the at least one PDSCH overlapping the second PDCCH, and
wherein in case that the second PDCCH is associated with a UE-specific search space, the at least one PDSCH overlapping the second PDCCH is transmitted.
4 . The method of claim 3 , wherein a maximum number of PDCCH candidates or a maximum number of control channel elements (CCEs) of the UE is changed based on at least one symbol overlapping with the at least one PDSCH, and
wherein the maximum number of PDCCH candidates or the maximum number of CCEs is defined for each slot or each span based on a UE capability.
5 . A user equipment (UE) in a communication system, the UE comprising:
a transceiver; and
a controller coupled with the transceiver and configured to:
receive, from a base station, a radio resource control (RRC) message including physical downlink shared channel (PDSCH) resource allocation information, transmission configuration indication (TCI) state information, and time duration information related to quasi co location (QCL),
receive, from the base station, downlink control information (DCI) for scheduling multiple PDSCHs on a first physical downlink control channel (PDCCH),
configure a first TCI state of PDSCHs within a time duration for QCL as a default TCI state based on a time offset between the first PDCCH and a first PDSCH of the multiple PDSCHs being less than the time duration for QCL,
receive, from the base station, the multiple PDSCHs scheduled by the DCI,
determine whether to skip monitoring a second PDCCH overlapping with at least one PDSCH within the time duration,
in case that a second TCI state of the second PDCCH is same as the first TCI state, monitor the second PDCCH, and
in case that the second TCI state of the second PDCCH is different from the first TCI state and a beam switching time is considered for switching a beam between the at least one PDSCH and the second PDCCH, determine to skip monitoring the second PDCCH,
wherein in case that the second PDCCH is associated with a common search space, rate matching or puncturing is performed on the at least one PDSCH overlapping the second PDCCH, and
wherein in case that the second PDCCH is associated with a UE-specific search space, the at least one PDSCH overlapping second PDCCH is received.
6 . The UE of claim 5 , wherein a maximum number of PDCCH candidates or a maximum number of control channel elements (CCEs) of the UE is changed based on at least one symbol overlapping with the at least one PDSCH, and
wherein the maximum number of PDCCH candidates or the maximum number of CCEs is defined for each slot or each span based on a UE capability.
7 . A base station in a communication system, the base station comprising:
a transceiver; and
a controller coupled with the transceiver and configured to:
transmit, to a user equipment (UE), a radio resource control (RRC) message including physical downlink shared channel (PDSCH) resource allocation information, transmission configuration indication (TCI) state information, and time duration information related to quasi co location (QCL),
transmit, to the UE, downlink control information (DCI) for scheduling multiple PDSCHs on a first physical downlink control channel (PDCCH), and
transmit, to the UE, the multiple PDSCHs scheduled by the DCI,
wherein, based on a time offset between the first PDCCH and a first PDSCH of the multiple PDSCHs being less than a time duration for QCL, a first TCI state of PDSCHs within the time duration for QCL is set as a default TCI state,
wherein in case that a second ICI state of a second PDCCH overlapping with at least one PDSCH within the time duration is same as the first TCI state, the second PDCCH is monitored,
wherein, in case that the second TCI state of the second PDCCH is different from the first TCI state and a beam switching time is considered for switching a beam between the at least one PDSCH and the second PDCCH, monitoring the second PDCCH is skipped,
wherein in case that the second PDCCH is associated with a common search space, rate matching or puncturing is performed on the at least one PDSCH overlapping the second PDCCH, and
wherein in case that the second PDCCH is associated with a UE-specific search space, the at least one PDSCH overlapping the second PDCCH is transmitted.
8 . The base station of claim 7 , wherein a maximum number of PDCCH candidates or a maximum number of control channel elements (CCEs) of the UE is changed based on at least one symbol overlapping with the at least one PDSCH, and
wherein the maximum number of PDCCH candidates or the maximum number of CCEs is defined for each slot or each span based on a UE capability.