| 摘要 |
<p>The invention relates to a method for the digital bidirectional data transmission in an optical fibre. Light pulses of the same frequency are used both for the forward and reverse direction of the data transmission. The pulses to be transmitted are reduced to a width Tr from an original width Tb, the mark/space ratio Tr/(Tb - Tr) having to be less than one. The second transmitting/receiving unit must only transmit during a receive pause (Tb - Tr). To achieve an optimum distribution of the optical pulses on the optical fibre 3, the first transmitting/receiving unit 1 measures the timing on the optical fibre 3 and, if necessary, causes the second transmitting/receiving unit 2 to change its transmitting time of its optical signals by means of a modify signal. This produces a control loop which automatically achieves an optimum pulse distribution on the optical fibre within certain limits. <IMAGE></p> |
