Method and apparatus for beam indication for uplink transmission in a wireless communication system

A method for a network, comprising:

• the network configures a first serving cell to a User Equipment (UE), and indicates the UE to activate the first serving cell and an active Uplink (UL) Bandwidth Part (BWP), wherein the first serving cell or the active UL BWP is not configured with Physical Uplink Control Channel (PUCCH) resource(s);
• the network does not indicate the UE to transmit a first Physical Uplink Shared Channel (PUSCH) in the first serving cell or the active UL BWP via a Downlink Control Information (DCI) format without spatial relation field when the UE is in Radio Resource Control (RRC) connected mode;
• and
• the network indicates to the UE to transmit a third PUSCH in a second serving cell, wherein the third PUSCH is scheduled by a DCI format 0_0 and the third PUSCH is transmitted through a spatial relation for transmitting a PUCCH resource configured in active UL BWP in the second serving cell and comprising the lowest resource ID among all PUCCH resources configured in active UL BWP in the second serving cell.

A UE (User Equipment), comprising:

• a control circuit;
• a processor installed in the control circuit;
• and
• a memory installed in the control circuit and operatively coupled to the processor, wherein the processor is configured to execute a program code stored in the memory to:
• be configured with a first serving cell, and being indicated to activate the first serving cell and an active Uplink (UL) Bandwidth Part (BWP), wherein the first serving cell or the active UL BWP is not configured with Physical Uplink Control Channel (PUCCH) resource(s);
• not expect to be indicated to transmit a first Physical Uplink Shared Channel (PUSCH) in the first serving cell or the active UL BWP in Radio Resource Control (RRC) connected mode, wherein the first PUSCH is scheduled by a Downlink Control Information (DCI) format without spatial relation field;
• and
• transmit a third PUSCH in a second serving cell through a spatial relation for transmitting a PUCCH resource configured in active UL BWP in the second serving cell, wherein the third PUSCH is scheduled by a DCI format 0_0, and the PUCCH resource comprises the lowest resource Identity (ID) among all PUCCH resources configured in the active UL BWP in the second serving cell.

A network node, comprising:

• a control circuit;
• a processor installed in the control circuit;
• and
• a memory installed in the control circuit and operatively coupled to the processor, wherein the processor is configured to execute a program code stored in the memory to:
• configure a first serving cell to a User Equipment (UE), and indicating the UE to activate the first serving cell and an active Uplink (UL) Bandwidth Part (BWP), wherein the first serving cell or the active UL BWP is not configured with Physical Uplink Control Channel (PUCCH) resource(s);
• prevent from or not be allowed to indicate the UE to transmit a first Physical Uplink Shared Channel (PUSCH) in the first serving cell or the active UL BWP via a Downlink Control Information (DCI) format without spatial relation field when the UE is in Radio Resource Control (RRC) connected mode;
• and
• indicate to the UE to transmit a third PUSCH in a second serving cell, wherein the third PUSCH is scheduled by a DCI format 0_0 and the third PUSCH is transmitted through a spatial relation for transmitting a PUCCH resource configured in active UL BWP in the second serving cell and comprising the lowest resource ID among all PUCCH resources configured in active UL BWP in the second serving cell.