Caller personal station equipped with simultaneous call function and multicast communication function and corresponding receiver personal station, and cell station and corresponding receiver personal station

摘要

The caller personal station of the present invention includes the following units: a channel search unit for scanning the plurality of communication channels to search for an unoccupied channel and regarding the unoccupied channel as a multicast channel; and a simultaneous call unit for repeatedly transmitting a simultaneous call frame on the multicast channel for a first predetermined time period, the simultaneous call frame indicating a simultaneous call to the other personal stations; a multicast unit for transmitting multicast frames on the multicast channel when a second predetermined time period has passed, the multicast frames containing data to be multicast. On receiving the simultaneous call frame by sequentially sensing the plurality of communication channels, the other personal stations enter a receiving state of multicast frames on the multicast channel. The simultaneous call unit includes the following units: a simultaneous call frame generation unit for generating the simultaneous call frame; a transmission timer for counting the first predetermined time period and generating a time-out; and a simultaneous call frame transmission unit for repeatedly transmitting the simultaneous call frame on the multicast channel from a start of counting the predetermined time period until the time-out is generated.