| 摘要 |
PURPOSE:To improve the efficiency of utilization of a transmission line, by transmitting a frame without any added preamble unless collision of the transmitted frame occurs. CONSTITUTION:In a system for asynchronous transmission and reception of an information frame having an added preamble, a collision detecting circuit 12 stops the transmission of the preamble once detecting no transmitted frame being sent out of another terminal station device, and sending out the transmitted information from a transmitted frame generating circuit 9 immediately. If another terminal station device sends out a transmitted frame, control to length corresponding to the priority of an information frame for transmitting the length of the preamble is carried out to send out the preamble successively until no collision is detected. |
