A Novel Optical Modulation Format CSNRZ

In this letter, together with the transmitter configuration, a novel modulation code format named carrier-suppressed nonreturn-to-zero (CSNRZ) is proposed. Unlike the conventional nonreturn-to-zero code (NRZ), return-to-zero (RZ) and carrier-suppressed return-to-zero (CSRZ) signals, this optical signal has reverse-phase optical amplitude in the periods corresponding to 0 bits comparing to 1 bits. With an additional transform module at the receiver side, this reverse-phase optical power can reduce the transmission power penalty due to fiber nonlinearity.