摘要 |
An optical transmitter for the joint transmission of analog and digital signals is indicated, which, although it contains an optical transmitting component (5) with a laser, does not exhibit an increase in the bit error rate when transmitting the digital signals, due to so-called clipping. The clipping, a negative overmodulation of the laser to below the laser threshold, which occurs because of the constructive interference of the analog signal carders, is prevented by a limiter (8) located upstream of the modulation input of the optical transmitting component (5). The limiter contains a time-variant network that supplies a specified minimum voltage to the modulation input every time a comparator (7) determines that the modulation voltage has dropped below the predetermined threshold.
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