Abstract
The performance of dual-carrier 400G solutions based on three high-order quadrature amplitude modulation (QAM) formats (8/16/32-QAM) is investigated on the same platform. We first study the benefit and penalty differences of gray and differential coding, and then experimentally compare OSNR sensitivities and transmission performance using flexible transceiver configuration and the same erbium-doped fiber amplifiers-only standard single-mode fiber link. Experimental results show the implementation penalties are 1.85 dB for 42-GBd polarization multiplexed (PM)-8QAM, which is 1 and 1.5 dB better than 32-GBd PM-16QAM and 25-GBd PM-32QAM at 5.92-dB Q <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> -factor (corresponding to a bit error rate of 2.4E-2), respectively. It is also found that maximum reaches of 2460 km for 42.6-GBd PM-8QAM, 1640 km for 32-GBd 16QAM, and 820 km for 25-GBd PM-32QAM are achieved. Furthermore, the performances of cascaded multimodulus algorithm and decision-directed least mean square (DD-LMS) algorithms are also compared. The improvement by addition of one sample/symbol-based DD-LMS digital filter is investigated as well.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
