720), the corresponding logical channel may be unable to transmit using a configured grant in the usable list or may fail to satisfy quality of service (QoS) requirements.

In this case, the corresponding logical channel may transmit data by using another configured grant that is not in the usable list (730). Otherwise, if all of the currently configured usable configured grants are usable, data may be transmitted with a usable configured grant according to the existing configuration (740).

FIG. 8 illustrates a method of changing a logical channel restriction proposed in the disclosure.

As described in the example of FIG. 3, the usable configured grant may be changed due to deactivation of the BWP, deactivation of a cell, or the like. In this case, as radio resources usable by a logical channel may not exist or may be insufficient, it is necessary to change the configured logical channel restriction. FIG. 8 shows an embodiment of a method for changing such a logical channel restriction.

When a usable configured grant is configured for a logical channel in which data transmission with a dynamic grant is not configured (not allowed) (810), the terminal may identify whether a configured grant usable for data transmission is changed with respect to the logical channel restriction configured for each logical channel. If at least one configured grant among the usable configured grants becomes unusable, in other words, if at least one usable configured grant is released, is deactivated, or is not configured on the active BWP (820), the corresponding logical channel may be unable to transmit using a configured grant in the usable list or may fail to satisfy quality of service (QoS) requirements.

In this case, the corresponding logical channel may transmit data by using another configured grant that is not in the usable list, or may transmit data by using a dynamic grant (830). Otherwise, if all of the currently configured usable configured grants are usable, data may be transmitted with a usable configured grant according to the existing configuration (840).

FIG. 9 illustrates a method of changing a logical channel restriction proposed in the disclosure.

As described in the example of FIG. 3, the usable configured grant may be changed due to deactivation of the BWP, deactivation of a cell, or the like. In this case, as radio resources usable by a logical channel may not exist or may be insufficient, it is necessary to change the configured logical channel restriction. FIG. 9 shows an embodiment of a method for changing such a logical channel restriction.

When a list of usable cells is configured for a logical channel (910), the terminal may identify whether there is a cell usable for data transmission with respect to the logical channel restriction configured for each logical channel. If there is no usable cell, in other words, if all usable cells are deactivated (920), the corresponding logical channel may be unable to transmit using a cell in the usable list.

In this case, the logical channel may transmit data by using a different cell that is not in the usable list. However, in a certain embodiment, the different cell may be the primary secondary cell (PSCell) or cells including the PSCell (930). As a more specific example, the different cell that is not in the usable list but is used for data transmission may be configured as a special cell (SPCell) including the PCell or PSCell. In another embodiment, as there is no usable cell, the corresponding RLC entity may be deactivated (RLC deactivation), and the PDCP entity may request discard of data in the corresponding RLC entity without sending any more data to be transmitted thereto. Otherwise, if a currently configured usable cell can be used, data may be transmitted via the usable cell according to the existing configuration (940).

FIG. 10 illustrates a method of changing a logical channel restriction proposed in the disclosure.

As described in the example of FIG. 3, the usable configured grant may be changed due to deactivation of the BWP, deactivation of a cell, or the like. In this case, as radio resources usable by a logical channel may not exist or may be insufficient, it is necessary to change the configured logical channel restriction. FIG. 10 shows an embodiment of a method for changing such a logical channel restriction.

When a list of usable cells is configured for a logical channel (1010), the terminal may identify whether there is a cell usable for data transmission with respect to the logical channel restriction configured for each logical channel. If there is no usable cell, in other words, if all usable cells are deactivated or no subcarrier spacings (SCS) of all usable cells are in the usable list (1020), the corresponding logical channel may be unable to transmit using a cell in the usable list.

In this case, the logical channel may transmit data by using a different cell that is not in the usable list. However, in a certain embodiment, the different cell may be the PSCell or cells including the PSCell (1030). As a more specific example, the different cell that is not in the usable list but is used for data transmission may be configured as a special cell (SPCell) including the PCell or PSCell. In another embodiment, as there is no usable cell, the corresponding RLC entity may be deactivated (RLC deactivation), and the PDCP entity may request discard of data in the corresponding RLC entity without sending any more data to be transmitted thereto. Otherwise, if a currently configured usable cell can be used, data may be transmitted via the usable cell according to the existing configuration (1040).

FIG. 11 illustrates a method of applying a logical channel restriction based on a physical layer priority.

The physical layer priority is a value defined to be used for prioritization or multiplexing in the physical layer with respect to corresponding radio resources. Here, if the physical layer priority of a corresponding resource is high, there is a need to include data that must be processed first. To this end, logical channel restrictions can be configured to take this physical layer priority into account. Such logical channel restrictions may have the following selection conditions.

- Logical channel that can use only a high physical layer priority resource
- Logical channel that can use only a low physical layer priority resource
- Logical channel that can use both a high physical layer priority resource and a low physical layer priority resource
- Logical channel that can use neither a high physical layer priority resource nor a low physical layer priority resource

According to embodiments, this logical channel restriction on the physical layer priority may be applied only to resources allocated with a dynamic grant and may be not applied to resources allocated with a configured grant. In another embodiment, this logical channel restriction on the physical layer priority may be not applied to resources allocated with configured scheduling-radio network temporary identifier (CS-RNTI) indicating configured grant retransmission or activation.