| 摘要 |
PURPOSE:To make voice communication and packet communication compatible and to make the packet communication efficient. CONSTITUTION:A reception radio wave intensity from a communication satellite 10 is detected by a reception level detector 40 and reception level data for a prescribed time are stored in a storage section 44 by implementing the detection for a prescribed time. When a perspective rate is discriminated to be 90% or over based on a reception level for 10min just before, for example, a changeover device 26 is thrown to the position of a voice communication system 30 to allow the voice communication system to be offered. Even when the perspective rate is 90% or below, if it is discriminated that the mobile equipment is stopped at a perspective location based on data from a running state detector 46, the voice communication service is offered. Furthermore, when the situation differs from those above, the packet communication service is selected, and the packet length and the packet re-transmission interval in this case are decided by the accumulation probability distribution of the perspective consecutive time and the shield consecutive time decided by the reception level for 10min just before. |
