| 摘要 |
PURPOSE:To expand the receptible range by a slave set with a small transmission output not affecting interference to other sets by allowing plural transmitters to send a signal to call a specific slave set sequentially by the start from a terminal equipment. CONSTITUTION:A private branch of exchange 4 or an operation console 5 is operated to send an ID and a data for a specific slave set from a terminal equipment to a transmitter 2a through a signal line 6. The transmitter 2a receives the signal and a control section 24 applies carrier sense and modulates an identification ID, an ID of a sender 2a, an ID of a destination transmitter 2b, an ID for a slave set to be called and a data by a transmission section 22 and radiates the result from an antenna 21 as a radio wave for a predetermined number of times. The transmitter 2b receives it, identifies each ID and sends an ACK signal, applies the same operation as the sender 2a and radiates the result from the antenna 21 as a radio wave. The transmitter sends the ID to call the specific slave set, the data and the ID of the transmitter to be started next sequentially. When any of the slave sets exists within the reception range of the transmitter, the slave set receives the signal. |
