| 摘要 |
PROBLEM TO BE SOLVED: To attain an extension speech through the use of an inter-slave set direct speech function not by way of a base station even when there is not a dead channel for communication between the mobile stations at the base station to prevent an extension speech by way of the base station at the time of executing the extension speech between the mobile stations registered to the base station. SOLUTION: When an extension calling is required from a mobile station 1, to a mobile station 13 when all the channels for communication between the base station and the mobile stations are used and there is no dead channel, the base station 2 returns a linked channel rejection to a linked channel establishing request from the mobile station 11, and the mobile station 11 receiving the linked channel rejection sends a signal requiring shift to an inter-slave set direct speech mode to the mobile station 13 by way of the base station 2 through the use of a control channel. Then at the time of receiving the signal requiring shift to an inter-slave set direct speech, the mobile station 13 transmits a confirming signal to the mobile station 11 by way of the base station 2 through the use of the control channel. Thereby the mobile stations 11 and 13 are switched to the inter-slave set direct speech mode. |
