一种适用于突发相干光通信的均衡和频偏估计的联合方法

A combination algorithm of channel equalization and frequency offset estimation for optical burst-mode coherent communication

为了适应光突发接收机的快速信道均衡和频偏估计的要求,提出一种时域均衡联合频偏估计的方法。频偏估计的叠加结果作为反馈用于电信道均衡器误差信号的计算,同时用于均衡器估计值的频偏补偿。通过仿真验证了时域均衡联合频偏估计可以提高系统性能,并对影响光突发接收机的参数设置进行了研究;仿真研究了自适应均衡联合频偏估计时光突发接收机适用的稳态频偏和光纤传输距离范围,当系统中存在1GHz的频偏时系统仍然能够传输180km以上。研究结果表明,本文提出的时域均衡联合频偏估计的算法,在当光突发接收机中存在频偏暂态效应时仍然能够有效完成信道均衡和频偏估计与补偿。

In order to meet the needs of fast channel equalization requirements for the optical burst mode coherent receiver,this paper proposes a method that combines electric channel equalization with frequency offset estimation, where the results from the frequency offset estimation contribute to tap coefficient updating of the equalizer and are also used for the frequency offset compensation. The simulation results show that the combination of the electric channel equalization and the frequency offset estimation can improve the performance of the optical burst-mode receiver, the parameters important for the optical burstmode coherent receiver are then found, and finally the range of steady state frequency offset and fiber transmission distance under which the optical burst-mode coherent receiver can work with the combination of frequency offset estimation and channel equalization are studied with simulation When there exists 1 GHz frequency offset in the system,180 km fiber transmission distance can be supported with the optical burst-mode coherent receiver. The simulation results show that the combination of the two modules in the optical burst-mode coherent receiver is able to complete channel equalization and frequency offset estimation and compensation effectively, even under the case with significant transient frequency offset in the optical burst-mode coherent receiver.