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arXiv · 2402.04395

Auto-Encoder Optimized PAM IM/DD Transceivers for Amplified Fiber Links

Amir Omidi·Mai Banawan·Erwan Weckenmann·Benoit Paquin·Alireza Geravand·Zibo Zheng·Wei Shi·Ming Zeng·Leslie A. Rusch
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Abstract

We examine pulse amplitude modulation (PAM) for intensity modulation and direct detection systems. Using a straight-forward, mixed noise model, we optimize the constellations with an autoencoder-based neural network (NN), an improve required signal-to-noise ratio of 4 dB for amplified spontaneous emission (ASE)-limited PAM4 and PAM8, without increasing system complexity. Performance can also be improved in O-band wavelength division multiplexing system with semiconductor optical amplifier amplification and chromatic dispersion. We show via simulation that for such a system operating at 53 Gbaud, we can extend the reach of PAM4 by 10-25 km with an optimized constellation and a NN decoder. We present an experimental validation of 4 dB improvement of an ASE-limited PAM4 at 60 Gbaud using an optimized constellation and a NN decoder.

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Amir Omidi, Mai Banawan, Erwan Weckenmann, Benoit Paquin, Alireza Geravand, Zibo Zheng, Wei Shi, Ming Zeng, Leslie A. Rusch. 2024-05-29. Auto-Encoder Optimized PAM IM/DD Transceivers for Amplified Fiber Links. https://arxiv.org/abs/2402.04395

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