Performance Optimization of Short Reach Optical Interconnects based on Direct Detection

Luca Poì; Stella Civelli; Marco Secondini; Li Zhang; Dario Cellini; Asfand Nizamani; Ramin Solaimani; Lorenzo De Marinis; Mareli Rodigheri; Pantea Nadimi Goki; Muhammad A. Naz; Giampiero Contestabile; Enrico Forestieri; Fabio Cavaliere

arXiv · 2608.28129

Performance Optimization of Short Reach Optical Interconnects based on Direct Detection

Luca Poì·Stella Civelli·Marco Secondini·Li Zhang·Dario Cellini·Asfand Nizamani·Ramin Solaimani·Lorenzo De Marinis·Mareli Rodigheri·Pantea Nadimi Goki·Muhammad A. Naz·Giampiero Contestabile·Enrico Forestieri·Fabio Cavaliere

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Abstract

Short-reach optical interconnects are evolving toward data rates beyond 400 Gb/s per lane, driven by the bandwidth and energy-efficiency requirements of AI-enabled datacenter networks. At these operating speeds, channel impairments, device nonlinearities, and hardware constraints limit the effectiveness of conventional transceiver design and digital signal processing (DSP). This paper presents a unified framework for the optimization of direct-detection optical interconnects, encompassing digital surrogate modeling, receiver-side DSP optimization, and end-to-end (E2E) transceiver learning. The proposed formulation provides a common perspective for model-based and machine-learning-based approaches, including linear and nonlinear equalization, lookup tables, decision trees, neural-network receivers, and E2E optimization. Their performance is discussed together with computational complexity and hardware implementation aspects, highlighting the associated trade-offs. We show, through simulations and experimental validations, that for a 40~Gb/s 10~km link, decision trees can outperform by 0.5--1~dB conventional linear equalization, with negligible hardware requirements. Moreover, we show that an E2E technique based on transformers can provide a gain up to 6~dB, highlighting the potential of joint transceiver optimization to improve the performance of next-generation short-reach optical links.

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Luca Poì, Stella Civelli, Marco Secondini, Li Zhang, Dario Cellini, Asfand Nizamani, Ramin Solaimani, Lorenzo De Marinis, Mareli Rodigheri, Pantea Nadimi Goki, Muhammad A. Naz, Giampiero Contestabile, Enrico Forestieri, Fabio Cavaliere. 2026-08-28. Performance Optimization of Short Reach Optical Interconnects based on Direct Detection. https://arxiv.org/abs/2608.28129

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