In optical communication systems, short blocklength probabilistic enumerative sphere shaping (ESS) provides both linear shaping gain and nonlinear tolerance. In this work, we investigate the performance and complexity of ESS in comparison with fiber nonlinearity compensation via digital back propagation (DBP) with different steps per span. We evaluate the impact of the shaping blocklength in terms of nonlinear tolerance and also consider the case of ESS with a Volterra-based nonlinear equalizer (VNLE), which provides lower complexity than DBP. In single-channel transmission, ESS with VNLE achieves similar performance in terms of finite length bit-metric decoding rate to uniform signaling with one step per span DBP. In the context of a dense wavelength-division multiplexing (WDM) transmission system, we show that ESS outperforms uniform signaling with DBP for different step sizes.
翻译:在光学通信系统中,短长区段概率性计算领域形成(ESS)既提供线性成型增益,也提供非线性容度。在这项工作中,我们调查ESS的性能和复杂性,与通过数字反向传播(DBP)和跨度不同步骤的纤维非线性补偿相比较,我们从非线性容度的角度评价成形区段长度的影响,并审议以伏尔泰拉为基础的非线性平衡器(VNLE)提供比DBP更复杂的情况。在单道传输中,VNLE的ES在有限长度比分度解码率方面达到类似的性能,以单步每波段统一信号。在密集波长视多轴传输系统(WDM)方面,我们显示ESS在与DBP不同步骤大小的统一信号上超过了DBP。