| 摘要 |
PURPOSE:To prevent the collision with other systems due to the information from a master station and the responding signal from a slave station by applying carrier sense only to the master station for the 1st prescribed time, sending a data when it is judged that other system is not in operation and allowing a slave station to send a reply signal within the 2nd prescribed time shorter than the 1st prescribed time. CONSTITUTION:Assuming that the master station 1 of the system I is within the interference area by the system II and the slave station 2 is at the outside of the interference area by the system II. The master station 1 of the system I applies carrier sense supervision for a time T when an information transmission request is caused (at time tIE) and sends information when no carrier is detected. When the slave station 2 of the system II receives the information, the station 2 sends a reply signal within a time (t). The master station 3 of the system II, when a transmission request is raised while the system I uses the radio wave (at a time tIE'), sends the information at a time T after the carrier of the master station of the system I is lost. Even if the slave station 2 of the system I is at the outside of the interference area from the system II, since the relation of T>t exists, the collision of the data is evaded in such a way. |
