Patent ID: 6917762

Claim:
An optical transmission system for compensating for transmission loss, comprising: a transmitting apparatus for serializing a plurality of n-bit channel data, where n is a natural number, received from an external source, in response to a predetermined clock signal, converting the serialized channel data into a first current signal and converting the predetermined clock signal into a second current signal, the magnitudes of the first current signal and second current signal being modulated in accordance with corresponding first and second transmission loss compensation signals decoded from an error detection signal received from a remote receiving apparatus, and outputting first and second optical signals having respective first and second optical output power levels corresponding to the respective magnitudes of the first and second current signals; first and second transmission optical fibers for transmitting the first and second optical signals; a receiving apparatus for recovering the n-bit channel data and the predetermined clock signal from the first and second optical signals received through the first and second transmission optical fibers, detecting first and second transmission loss in each of the first and second optical signals as a result of their transmission and reception to generate first and second transmission loss signals, encoding the first and second transmission loss signals to generate an encoded transmission loss signal, and optically converting the encoded transmission loss signal as the error detection signal; and a return optical fiber for transmitting the error detection signal to the transmitting apparatus.