ABSTRACT We propose an adaptive phase-diversity method for optical M-ary differential phase-shift keying (MDPSK) homodyne receivers, to achieve coherent optical communication. This method involves eliminating the random fluctuations in the phase differences between the signal light and local oscillator and the in-plane and quadrature signal (IQ) imbalance compensation. For the former, a phase-diversity method, which can theoretically eliminate all phase-related noise, is proposed. The gain and phase imbalances between the I and Q channels can be compensated completely by using automatic phase- and gain-control systems. The core idea is the adaptability of the receiver to the local phase shift of the local oscillator. The performance of the receiver is not sensitive to environmental factors such as temperature and vibrations. Our simulation results show that the imbalances between the IQ channels can be completely compensated over a wide imbalance range, and the baseband signals can be accurately recovered using the proposed scheme.

中文翻译：

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一种具有自适应相位分集的 MDPSK 零差接收机

摘要 我们提出了一种用于光多进制差分相移键控 (MDPSK) 零差接收器的自适应分相方法，以实现相干光通信。该方法涉及消除信号光和本地振荡器之间相位差的随机波动以及平面内和正交信号 (IQ) 不平衡补偿。对于前者，提出了一种理论上可以消除所有与相位相关的噪声的相位分集方法。I 和 Q 通道之间的增益和相位不平衡可以通过使用自动相位和增益控制系统来完全补偿。核心思想是接收器对本地振荡器的本地相移的适应性。接收器的性能对温度和振动等环境因素不敏感。