| 摘要 |
PROBLEM TO BE SOLVED: To obtain a radio communication system capable of transmitting a signal prompting the installation of a relay apparatus, from a base station to a moving radio terminal in a situation where no relay apparatus is fixed beforehand. SOLUTION: The radio communication system includes a plurality of mobile terminals, a base station with these terminals under control and a relay apparatus, wherein prior to starting communication, the base station calculates a radio reach range depending on a reference value based on performance resources, expansion routes and map data of the mobile terminals and calculates a radio reach range depending on a theoretical value by applying, to the calculated radio reach range, geographical information of obstacles or the like on an activity site and additional conditions such as weather, route fault and the like. Further, after starting communication with a radio terminal, based on location information of the radio terminal and a measured parameter of a radio signal, the base station calculates a radio reach range, depending on a measured value, in which stable communication with the radio terminal can be maintained and ensured. If the location of the radio terminal comes near getting out of the range, a signal prompting the installation of the relay apparatus is sent to the radio terminal. COPYRIGHT: (C)2009,JPO&INPIT |
