一种新型的低成本双向传输相干无源光网络系统

A novel low cost bidirectional transmission coherent passive optical network system

基于相干光通信技术,提出一种采用直调激光器(DML)的光网络单元(ONU)收发装置及系统结构,其主要用于密集波分复用无源光网络。低成本的单DML同时用于上下行传输链路,以减少所需光源的数量。通过实验分析比较了不同驱动电压及偏置电流对DML的影响,同时也分析了上下行数据的频率间隔和反向瑞利散射对双向传输系统性能的影响。实验结果表明,该方法具有较好的系统接收灵敏度性能,同时能够有效降低相干无源光网络系统的成本和复杂性。

Based on the coherent optical reception technology, a cost-effective structure for the optical network unit （ONU） transceivers in uhra-dense wavelength division multiplexing passive optical network using a single directly modulated laser （DML） was proposed. To reduce the number of required light sources, only one DML was used in both upstream and downstream links. By experimental investigations, the impacts of driving amplitude and bias current on DML＇s performance were analyzed. Meanwhile, the impact of frequency spacing between upstream and downstream signal and the Rayleigh backscattering interference on system performance were investigated. The method has better performance of system receiving and can effectively reduce the cost and complexity of coherent passive optical network system.