| 摘要 |
The invention provides a communication system for a three-phase power distribution network comprised of a plurality of remote devices (37, 63), with certain of the remote devices being used as signal repeaters (37). Injection point circuitry (1) provides an out-going communication signal which is coupled (15, 16, 17) to the three-phase conductors (11, 12, 13) such that each phase conductor carries an identical, independent, outgoing communication signal. The signal repeaters are each coupled (43, 44, 45) to at least two of the three-phase conductors. Each signal repeater includes circuitry (48 or 73) for producing a composite signal in response to the coupled signals. The composite signal has a signal-to-noise ratio typically superior to, but not worse than, the signal-to-noise ratio of the rest of the coupled signals. The remainder of the remote devices (63) are independently coupled (66, 69) to at least one of the three-phase conductors so as to facilitate communication with each of the remote devices. |
