To provide a wireless system in which a terminal that is shutdown or on in standby can be activated from a remote site in an environment where connection is attested by an authentication server, using security technology for wireless LAN, a different encryption key from other terminals is employed in the communication, and the encryption key is periodically renewed. An access point controls a beacon transmission interval control part by recognizing a terminal activation signal from a management terminal. The beacon transmission interval control part controls the transmission interval of beacon by switching between a normal operation mode and a patterned transmission interval mode. A beacon transmission interval detection circuit of a terminal monitors interval between beacons, and upon detecting patterned beacons, outputs a detection signal. A wireless module receives the detection signal from the beacon transmission interval detection circuit, and then makes an activation request to the terminal.