| 摘要 |
<p>A method of transmitting data symbols (RDAT; RDAT1; RDAT2) between network elements in a digital teletransmission network (1) comprises the steps of transmitting the data symbols from a first network element (2) to a second network element (3) by modulating a signal having a first wavelength ( lambda DAT; lambda DAT1; lambda DAT2) ; receiving in the second network element the data symbols by demodulation of the signal having a first wavelength, calculating a number of extra symbols (RFEC) from the data symbols, transmitting also the extra symbols; receiving in the second network element the extra symbols; and utilizing them for error correction of the received data symbols. The extra symbols are transmitted from the first network element by modulating a signal having a second wavelength ( lambda FEC) different from the first wavelength. By using a separate wavelength for the extra symbols the data symbols can be transmitted unaffected according to the normal standards. <IMAGE></p> |
