The invention discloses a
base station, which comprises a downlink control information generating and sending unit, wherein the downlink control information generating and sending unit is used for sending downlink control information to
user equipment through a physical downlink
control channel on a component carrier; the downlink control information comprises first type downlink control information and / or second type downlink control information; the first type downlink control information comprises shared downlink control information and
user equipment special downlink control information; and the second type downlink control information comprises indication information related to monitoring collection of the physical downlink
control channel of the
user equipment and component carrier activation / close. Correspondingly, the invention also discloses the user equipment, and a method which is used for sending and detecting the downlink control information of the
base station and the user equipment respectively. According to the invention, the user equipment can realize fast and effective blind detection process and component carrier activation and close processes, so that the complexity of the blind detection and the
power consumption for receiving component carrier data are effectively reduced.