We experimentally demonstrate 208-Gb/s/ $\lambda $ discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S OFDM) transmission over a 40-km standard single-mode fiber without chromatic dispersion compensation using a low-cost… Click to show full abstract
We experimentally demonstrate 208-Gb/s/$\lambda $ discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S OFDM) transmission over a 40-km standard single-mode fiber without chromatic dispersion compensation using a low-cost direct-detection architecture based on the dual-driver Mach–Zehnder modulator (MZM). One twin-single sideband (SSB) signal is generated by driving the upper and lower arms of a dual-driver MZM with a real signal and its respective Hilbert pair. A MIMO-Volterra equalizer is proposed to mitigate the interference and nonlinearity penalty of the twin-SSB signal. Using the Twin-SSB without the MIMO algorithm can only reach 165 Gb/s/$\lambda $ , and applying a conventional SSB can only achieve 164 Gb/s/$\lambda $ with a bit error ratio less than $5\times 10^{-3}$ . However, we achieve a 240-Gb/s/$\lambda $ twin-SSB DFT-S OFDM signal in the back-to-back (BTB) case using the twin-SSB signal and MIMO-Volterra Equalization method, which implies that double spectral efficiency and more than 45% data rate improvement are obtained.
