An optical transceiver which modulates an optical source using digital control data, the modulator using output from a function generator

摘要

An optical transceiver 100 modulates an optical source 210 such as a laser using a modulator 220. The modulator receives both content data and digital control data. The digital control data may be input to the transceiver using an electrical two-wire serial interface 520, 540. A processor 410 uses the digital control data as a basis for deriving modulation information, such as parameters of a tone signal. This modulation information is used by a function generator 460. Its output is passed through a digital-to-analogue converter 450 and then input to the modulator, optionally to provide a tone signal. The processor also receives control information from an analogue-to-digital converter (ADC), and uses this to control the modulation. The input to the ADC may include a signal representing both the output from a laser monitor 440 and a low pass filtered 430 version of an optical signal received at optical detector 310, as claimed in GB2406010.