Abstract:
A base station of a carrier aggregation system sets a time division duplex (TDD) component carrier of a plurality of TDD component carriers to a primary serving cell of a terminal and sets at least one frequency division duplex (FDD) component carrier of a plurality of FDD component carriers to a secondary serving cell of the terminal, and when a hybrid automatic repeat request-round trip time (HARQ RTT) value of a TDD component carrier of a primary serving cell of the terminal does not satisfy a quality of service (QoS) requirement of a service that the terminal requests, the base station changes a HARQ feedback transmitting resource that is set to the terminal.
Abstract:
According to an exemplary embodiment of the present invention, a master base station selects a target serving cell in which a state is changed, among the serving cells of at least one slave base station set in the terminal, generates a MAC control element which instructs a state change of the target serving cell, and then directly transmits the MAC control element to the terminal in the case of an uplink asynchronous state between the target slave base station managing the target serving cell and the terminal.