Patent ID: 8315259

Claim:
A base station using any frame of an incoming group of frames which a mobile station intermittently receives to send a paging announcement to the mobile station, said base station comprising a transmitter unit enabling, for the mobile station, to receive a multicast-related data when the mobile station receives the incoming group of frames, by sending, from the transmitter, the multicast-related data necessary to receive a multicast data by the mobile station by using any of the incoming group of frames, wherein the transmitter is operative to synchronize a transmission timing of the multicast-related data with a frame for monitoring paging announcements to the mobile station in the idle mode, the transmission timing of the incoming group of frames is determined based on a paging cycle requested by the mobile station individually, and the multicast data is transmitted according to a transmission cycle characteristics determined for respective multicast channels and received by a plurality of mobile stations including said mobile station, where the multicast-related data includes the multicast data MBS-DATA which is a content required by the mobile station and a MBS-DATA IE which indicates a frame for delivering the MBS-DATA.