| 摘要 |
PROBLEM TO BE SOLVED: To attain communication with a slave set even when direct radio communication between a master set and the slave set is disable because of a succeeding cause regardless of possible radio communication between the master set and the slave set at installation by requesting a relay of communication to other radio slave set when the concerned slave set does not reply the call. SOLUTION: For example, communication is tried between a master set 1 and a slave set 3-1, the slave set 3-1 sometimes does not reply regardless of making a call from the master set 1 to the slave set 3-1 owing to fading or the like caused by an obstacle located in the communication zone. In this case, the master set 1 selects a slave set (relay slave set) to request relay of communication with the slave set 3-1, e.g. a slave set 3-2 as the relay slave set to try the communication relay. When the relaying is possible, the master set 1 makes communication with the slave set 3-1 by way of the slave set 3-2. Radio communication is possible between the master set and the slave set at installation but even when the radio communication is not available between the master set 1 and the specific slave set 3-1 by succeeding fault, the disable communication is solved. |
