High Capacity Optical Communication Systems Using Mode Division Multiplexing

With the fast progress in academic research, the transmission capacity over the single mode fiber (SMF) has been demonstrated more than 100 Tb/s, together with wavelength division multiplexing (WDM), polarization division multiplexing (PDM), coherent detection, and higher-order modulation formats. However, 100 Tb/s is considered as the capacity limit of SMF, which is constrained by the fiber nonlinearity and optical signal to noise ratio. In this paper, using mode division multiplexing combined with coherent WDM PDM-DFTs-OFDM-32QAM, we successfully demonstrate 200-Tb/s (375 x 3 x 178.125-Gb/s) signal over 1-km few mode fiber (FMF) employing both C- and L-bands with 25-GHz channel spacing, achieving a spectral efficiency of 21.375-bit/s/Hz in both C/L-band.