| 摘要 |
PURPOSE:To easily communicate with a mobile body at a fixed point and to supply the operation energy in a fixed repeater from a mobile repeater to eliminate a need of a power line by providing repeaters and approximating them to transmit and receive signals of a communication transmission line fixedly installed in a building or the ground and a mobile body with a magnetic flux. CONSTITUTION:A metal cable 19 of the communication transmission line of a fixed device as a master 1 transmits and receives a communication signal to and from a mobile body 18 at a fixed point preliminarily provided as the relay point by a high frequency alternating magnetic flux modulated by this signal. The fixed repeater and the mobile body repeater which have induction loops 10 and 11 and are inductively coupled are provided with a gap or a small space between them to transmit and receive the signal with the magnetic flux. The circuit in the fixed repeater is operated by a minute power having a specific frequency component transmitted from the mobile body repeater to the fixed repeater. Thus, an optical fiber cable of satisfactory insulating property is used as the communication transmission line instead of the metal cable to improve the resistance to thunderbolt and the waterproof property. |
