| 摘要 |
PURPOSE:To realize a system capable of detecting simply a collision of signals, by deciding a collision of signals if a receiving signal is detected within a period from the starting time of transmission at own station through the delay time of transmission for the signal of own station. CONSTITUTION:When the optical signal of another station is received before the reception of the optical signal of own station, an output signal 15c of a waveform shaping circuit 9 is fed to an integration circuit 12. Then the circuit 12 delivers an output signal 18b of integration circuit in response to the input of the signal 15c. The signal 18b exceeds the threshold value 17 of decision at a time point 24, and a comparator 13 delivers a significant signal to an AND circuit 21b. The circuit 21b secures an AND of outputs of a transition detecting circuit 20b and the comparator 13 and then delivers a collision detecting significant signal 25. When no collision of signals occurs, a receiving signal 15a delivered from the circuit 9 is supplied to the circuit 12. Then the circuit 12 delivers an output signal 18c of integration circuit. |
