DFT-Spread OFDM for Fiber Nonlinearity Mitigation

Abstract
We study the transmission performance of the recently proposed multiband discrete-Fourier-transform spread orthogonal frequency-division multiplexing (MB-DFT-S-OFDM) format in which each subband is in essence a single-carrier signal with Nyquist bandwidth. We have found that the optimal subband bandwidth for a 428-Gb/s MB-DFT-S-OFDM signal is 15 and 3 GHz for inline dispersion compensated (IDC) and nondispersion compensated (NDC) fiber links, respectively. The optimized MB-DFT-S-OFDM outperforms the coherent single-carrier by 1 dB (0.8 dB) after 1000-km transmission over IDC (NDC) links.