A joint and robust frequency offset (FO) and phase noise tracking scheme using self-learning Kalman filter is proposed and demonstrated experimentally. In our scheme, a self-learning Kalman filter based on kurtosis error is used to track FO and phase noise simultaneously in a decision-free manner. Then, a mean-shift clustering-assisted maximum likelihood estimator is used for residual phase noise compensation. Simulation results indicate that the proposed scheme has advantages in FO estimation accuracy, OSNR sensitivity penalty, and FO jitter rate tolerance and nonlinearity tolerance, compared with the conventional FO and phase noise estimation scheme. With 7% FEC threshold, the proposed scheme can tolerate FO jitter rate up to 10 MHz for 16QAM, which is around 100 times and 20 times than that of VVPE1 +BPS and FFT+UCPE. With 1 dB OSNR penalty, the linewidth tolerance of the proposed scheme is 300 kHz for 64QAM, which is around 30 times and 5 times than that of FFT+UCPE+ML and FFT+ VVPE2. The proposed scheme also shows excellent nonlinearity tolerance over wide launched power, and it provides around 0.4 dB and 0.2 dB Q-factor improvement over VVPE1+ VVPE2, VVPE1 +BPS for 16QAM, respectively. The 28GBaud PDM 16QAM experimental results also indicate that the proposed scheme outperforms the rest of tested scheme under both back-to-back and fiber transmission cases. With optimal launched power, the proposed scheme can provide around 0.2 dB, 0.4 dB, and 0.7 dB Q-factor improvement over VVPE1 +BPS, FFT+UCPE, and VVPE1+ VVPE2 after 915 km fiber transmission, respectively. To the best of our knowledge, it is the first time that a joint and modulation transparent with robust nonlinearity and FO jitter rate tolerance is proposed and demonstrated for 64QAM.

中文翻译：

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用于智能接收器的使用自学习卡尔曼滤波器的调制透明且鲁棒的频偏和相位跟踪方案


提出并通过实验证明了一种使用自学习卡尔曼滤波器的联合鲁棒频率偏移（FO）和相位噪声跟踪方案。在我们的方案中，基于峰度误差的自学习卡尔曼滤波器用于以无决策的方式同时跟踪 FO 和相位噪声。然后，使用均值漂移聚类辅助的最大似然估计器进行残余相位噪声补偿。仿真结果表明，与传统的FO和相位噪声估计方案相比，该方案在FO估计精度、OSNR灵敏度损失、FO抖动率容限和非线性容限方面具有优势。在7％的FEC阈值下，所提出的方案可以容忍16QAM高达10 MHz的FO抖动率，分别是VVPE1 + BPS和FFT + UCPE的100倍和20倍左右。在 OSNR 损失为 1 dB 的情况下，该方案的线宽容限对于 64QAM 为 300 kHz，分别是 FFT+UCPE+ML 和 FFT+ VVPE2 的 30 倍和 5 倍。所提出的方案还在宽发射功率范围内表现出出色的非线性容限，并且与 16QAM 的 VVPE1+ VVPE2、VVPE1 +BPS 相比，Q 因子分别提高了约 0.4 dB 和 0.2 dB。 28GBaud PDM 16QAM 实验结果还表明，在背靠背和光纤传输情况下，所提出的方案均优于其余测试方案。在最佳发射功率的情况下，所提出的方案在 915 km 光纤传输后可分别比 VVPE1 +BPS、FFT+UCPE 和 VVPE1+ VVPE2 提供约 0.2 dB、0.4 dB 和 0.7 dB 的 Q 因子改善。据我们所知，这是第一次针对 64QAM 提出并演示了具有鲁棒非线性和 FO 抖动率容限的透明联合和调制。