| 摘要 |
PURPOSE:To reduce considerably the time needed to decide a retransmission position by using a cyclic counter which works asynchronously at each transmission/reception station in place of a conventional random number generaor and deciding the retransmission position of the collided data according to the count value of said counter in case the collision of data occurs. CONSTITUTION:A cyclic counter 14 has a satisfactory count-up speed compared with the slot length and performs counting repetitively like 0-4, 0-4,... up to the prescribed value. These counters 14 of each station work asynchronously with each other, and each station has a different time position to know the collision of packets according to the difference between the transmission delay time and the time needed for detection. Therefore the present count values are different from each other among counters 14 of each transmission/reception station when these count values are read by the transmission/reception station that detected the collision of packets. Thus the count value of the counter 14 is defined as the retransmission position of the packet of each station. This reduces the time needed to decide the retransmission position. |
