1-Tb/s dual-carrier 80-GBaud PDM-16QAM WDM transmission at 5.2 b/s/Hz over 3200 km

We demonstrate a 1-Tb/s dual-carrier PDM-16QAM interface (all-electronic 80-GBaud per subcarrier). We transmit five dual-carrier channels over 3200 km at 5.2-b/sHz spectral efficiency, implementing coherent detection, off-line digital signal processing, and soft-decision forward error correction.