| 摘要 |
<p>Optimum routing for communications between a central control unit (CCU) and remote units (nodes), such as electricity meters, distributed on an electrical power line is established by broadcasting from the CCU an interrogation signal to be received by the remote units. In response to a receipt of the interrogation signal, each remote unit returns an acknowledgement signal, time multiplexed with the acknowledgement signals of the other remote units, to the CCU which determines which units, if any, are "mute", i.e., have not acknowledged. The CCU then selects remote units in proximity to the mute remote units if it has already a good knowledge of the network or at random otherwise, to function as relays and repeats interrogation of the remote units via the relays. This process is repeated, if necessary, until communication paths between the CCU and all remote units are established directly or via relay units, to form maps. Numerous maps developed for the nodes during various time periods having different power line interference characteristics are stored in a data base to be accessed by the CCU to quickly establish an optimum route during subsequent periods having similar line interference characteristics.</p> |
