Spectrally efficient terabit optical transmission with Nyquist 64-QAM half-cycle subcarrier modulation and direct detection

We demonstrate 1.728 Tb/s (16 x 108 Gb/s) direct-detection wavelength division multiplexing (WDM) transmission over 80 km standard single mode fiber (SSMF) with Nyquist 64-ary quadrature amplitude modulation (64-QAM) and half-cycle subcarrier modulation. Each channel carries single sideband 18 GBaud 64-QAM signal and the channel spacing is 27 GHz. Considering 20% soft-decision forward error correction and frame redundancy, a net spectral efficiency record of 3.25 b/s/Hz is achieved for 100 G single polarization direct-detection WDM transmission. (C) 2016 Optical Society of AmericaNational Natural Science Foundation of China (NSFC) [61535002, 61475004]SCI(E)EIARTICLEfzhang@pku.edu.cn122767-27704