System for transmitting on a fibre optic physical carrier a principal data stream and a secondary data stream.

摘要

A transmission system which provides for the sending over a single fibre optic medium FO of a secondary data stream at the same time as a principal data stream codified according to line codes of the 1B/2B type. The transmitter station of the transmission system provides for an insertion unit UI provided with means capable of detecting the presence of a "one" bit in the principal data stream, and also capable of substituting the configuration normally provided for the codifying of this bit with the configuration which is unused by the line code from which the transmission of a "one" bit in the secondary data stream was each time requested beforehand. The receiver station comprises an extraction unit which provides for the presence of means capable of detecting the presence of the said unused configuration in the received stream, and of reconstructing the secondary data stream on the basis of the result of such detections.