| 摘要 |
PROBLEM TO BE SOLVED: To obtain a distribution line carrier system, capable of surely transmitting/receiving a text by carrier signals between a master station and slave stations, even when signal attenuation or deteriorated S/N ratio occurs on a distribution path. SOLUTION: A plurality of slave stations 13a-13h are connected to the master station 11 via a loop distribution path 12a connected to a distribution line 12, and a filter device 17 for controlling passage of carrier signals is provided halfway the path 12a. Normally, the device 17 prevents the carrier waves from passing to allow a bus-distribution path to transmit/receive the text by the carrier signals. When the signal attenuation or deteriorated S/N ratio occurs on the path 12a, the device 17 allows the carrier waves to pass, thereby transmitting/receiving the text by the carrier signals via a path opposite to the path 12a. COPYRIGHT: (C)2004,JPO
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