Multi-Tb/s optical transmission based on polarization-multiplexed LDPC-coded multi-band OFDM

Low-density parity-check (LDPC) coded multi-band orthogonal frequency division multiplexing (OFDM) is one of the promising pathways to achieve ultra-high speed long-haul optical transmission. In this paper, we study multi-Tb/s serial optical transport with efficient channel estimation. By using 16-ary QAM-based polarization-multiplexing with five frequency-locked lasers, used to carry coded-OFDM signal of aggregate data rate 400-Gb/s, we are able to achieve the total aggregate rate of 2 Tb/s. When the pilot-based channel estimation is used based on either LS or LMMSE criteria, together with channel interpolation based on piece-wise linear interpolation or piece-wise second-order interpolation, we can compensate for the accumulated chromatic dispersion over 6500 km of SMF and differential group delay of 500 ps simultaneously with small penalty (within 0.23 dB) dB, when LDPC codes of rate 0.8 are employed.