| 摘要 |
PROBLEM TO BE SOLVED: To improve availability of a communication circuit and also to decrease the useless repeated calls by deciding the presence or absence of communication data, detecting the circuit disconnection reason, disconnecting a radio link when a circuit disconnection enabling signal is received, establishing the radio link when the transmission of data is required and restarting the communication of data. SOLUTION: When a mobile station data communication terminal 1 receives a disconnection signal from a mobile station 2, the terminal 1 inquires of the station 2 about a non-data circuit disconnection enabling signal and the circuit disconnection reason and carries on the communication of data if it's decided that the circuit is disconnected by its quality deterioration. A radio data communication device 3 also continues its data communication state when the circuit is disconnected by its quality deterioration. If no data are transmitted within a prescribed fixed time, the station 2 disconnects a radio link 6 in response to a circuit disconnection instruction. At the same time, the terminal 1 receives the non-data circuit enabling signal from the device 3 and the device 3 transmits the non-data circuit enabling signal. Thus, a data communication state is maintained. |
