Hybrid Model Driven Dual Polarization Autoencoder for End-to-End Learning in Long-Haul Coherent Optical Systems
摘要
This work demonstrates a hybrid dual-polarization autoencoder (DPAE) framework for long-haul coherent optical fiber communication (OFC) by jointly optimizing a geometrically shaped M-ary quadrature amplitude modulation (QAM) constellation and a convolutional neural receiver over a physically scaled Manakov split-step Fourier method (SSFM) channel model. The long-haul optical link is implemented to emulate a realistic system by incorporating chromatic dispersion (CD), Kerr nonlinearity, attenuation, span-wise amplified spontaneous emission (ASE) noise, and laser phase noise into a fully differentiable channel layer, ensuring physics-consistent optimization. Furthermore, a deterministic electronic dispersion compensation (EDC) block is integrated before the neural decoder to bound the optimization state-space and mimic a practical coherent receiver, allowing the convolutional neural network (CNN) to focus exclusively on residual nonlinear and phase-noise impairments. The proposed framework is systematically evaluated over a 32 GBd, 1000–4000 km optical link across a wide operational grid of launch powers and effective signal-to-noise ratios (SNRs) by observing the pre-forward-error-correction (pre-FEC) bit-error rate (BER), symbol accuracy, generalized mutual information (GMI), and computation complexity. Performance analysis demonstrates that the hybrid transceiver can be optimized end-to-end at the bit level under realistic physical constraints, achieving minimum pre-FEC BERs of approximately