CODED MODULATION FOR SMALL STEP-SIZE VARIABLE SPECTRAL EFFICIENCY

摘要

A system and method involving a coded modulation scheme is provided whereby different spectral efficiencies can be achieved for different transmitters (TX1, TX2TXN) in a WDM system using the same M2-QAM modulation format. A maximum achievable spectral efficiency for the transmitters (TX1, TX2TXN) may be selected (202) and a spectral efficiency step-size of the maximum achievable spectral efficiency may be specified. The spectral efficiency for any transmitter (TX1, TX2TXN) in the system may be individually selected by reducing its spectral efficiency from the maximum achievable spectral efficiencies by a selected number of steps corresponding to the step size.