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arXiv · 2303.17248

Probabilistic Shaping for High-Speed Unamplified IM/DD Systems with an O-Band EML

Md Sabbir-Bin Hossain·Georg Bocherer·Talha Rahman·Tom Wettlin·Nebojsa Stojanovic·Stefano Calabro·Stephan Pachnicke
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Abstract

Probabilistic constellation shaping has been used in long-haul optically amplified coherent systems for its capability to approach the Shannon limit and realize fine rate granularity. The availability of high-bandwidth optical-electronic components and the previously mentioned advantages have invigorated researchers to explore probabilistic shaping (PS) in intensity-modulation and direct-detection (IM/DD) systems. This article presents an extensive comparison of uniform 8-ary pulse amplitude modulation (PAM) with PS PAM-8 using cap and cup Maxwell-Boltzmann (MB) distributions as well as MB distributions of different Gaussian orders. We report that in the presence of linear equalization, PS-PAM-8 outperforms uniform PAM-8 in terms of bit error ratio, achievable information rate and operational net bit rate indicating that cap-shaped PS-PAM-8 shows high tolerance against nonlinearities. In this paper, we have focused our investigations on O-band electro-absorption modulated laser unamplified IM/DD systems, which are operated close to the zero dispersion wavelength.

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Md Sabbir-Bin Hossain, Georg Bocherer, Talha Rahman, Tom Wettlin, Nebojsa Stojanovic, Stefano Calabro, Stephan Pachnicke. 2023-03-30. Probabilistic Shaping for High-Speed Unamplified IM/DD Systems with an O-Band EML. https://doi.org/10.1109/jlt.2023.3263039

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