This paper proposes, designs, and validates a filterless metro network employing bidirectional transmission over a single fiber. Transmission impairments, dominated by cross talk, are specifically estimated leveraging on what we believe to be novel closed-form expressions to determine optical reach, launch power, and number of supported cascaded nodes. Results show that extremely good transmission performance can be achieved and further improved when misalignment in spectrum allocation is configured among the two counter-propagating directions. This confirms that filterless metro networks employing bidirectional transmission over a single fiber represent an extremely attractive solution, particularly in the case of scarce fiber availability and when regulatory aspects impose a rent for any occupied fiber infrastructure.

中文翻译：

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双向单纤维无滤光网络：建模和实验评估

本文提出，设计并验证了在单根光纤上采用双向传输的无滤波器城域网。串扰占主导的传输障碍是根据我们认为是新颖的封闭形式表达来具体估算的，以确定光学距离，发射功率和支持的级联节点数。结果表明，当在两个反向传播方向之间配置频谱分配中的失准时，可以实现并进一步改善极好的传输性能。这证实了在单根光纤上采用双向传输的无滤波器城域网代表了一种极具吸引力的解决方案，尤其是在光纤稀缺和监管方面要求占用任何光纤基础设施租用的情况下。