| 摘要 |
Each receiver of a radio messaging installation has a radio frequency head (12) and a logic unit (16) for interpreting messages, including a memory containing an identification address specific to the receiver. The transmitter is provided for transmitting the messages intended for one of the various groups of receivers only in the time slices allocated to this group; the logic unit (16) for interpreting and for turning-on is provided for remaining on standby from the time the receiver (10) is turned on until identification of the address of the group in a message originating from the transmitter, then, cyclically, turning on the head for the periods framing the time slices allocated to the group. The receivers are distributed moreover into N hypergroups, each of which comprises receivers belonging to several of the groups, and possibly to all of the groups. The transmitter distributes the messages to be transmitted into hyperframes each allocated to a hypergroup, each having a special code word MS specific to the hyperframe. The logic unit (16) cuts off the power supply to the head (12) during the sending of the hyperframes to which the receiver is not allocated. <IMAGE>
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