Experimental Characterization of <tex>$10 \times 8$</tex> GBd DP-1024QAM Transmission with 8-bit DACs and Intradyne Detection

Abstract

We experimentally investigate the transmission of 10 × 8 GBd DP-1024QAM over full Raman amplified low-loss fiber spans. For multicarrier systems using 8-bit DACs, a record achievable information rate of 15.7 bit/symbol is observed after 200 km using standard intradyne detection.

Increasing achievable information rates with pilot-based DSP in standard intradyne detection

“…Moreover, the required pilot overhead of less than 5% has been experimentally achieved for each QAM format. We have determined new upper bounds on AIRs of 17.4 b/4D-symbol and 15.9 b/4D-symbol at 15 GBd and 30 GBd, respectively, which correspond to AIR exceeded previous work [16] with 8-bit digital-to-analogue converters while symbol rates were doubled or more. These result in the throughput values of 261 Gb/s and 477 Gb/s for a single carrier transmission at 15 GBd and 30 GBd, respectively.…”

“…This approach avoids the requirement for modifications to the optical configuration while making it possible to implement effective equalisation and carrier-phase recovery with a low computational complexity [14,15]. Recently, AIR upper bound values of 15.9 b/4D-symbol for uniform 1024 QAM and 16.8 b/4D-symbol for probabilistically-shaped 1024 QAM have been reported for back-to-back configurations with 8-bit DACs, driven at 8 GBd [16].…”