Abstract We numerically investigate the statistical characteristics of mode couplings induced by concatenated multiple few-mode fiber connections with lateral misalignments in weakly-coupled mode division multiplexed (MDM) systems. For the currently-feasible connectors, the probability of the crosstalk ratio being smaller than -20 dB is remarkably degraded as increasing the number of the connections. The currently-feasible connectors are not applicable to the weakly-coupled MDM systems. In order to suppress the mode crosstalk by smaller than -20 dB, the misalignment deviation is required to be smaller than 0.04, which corresponds to be 0.3% of the mode field diameter of the fundamental mode. In addition, we propose the simple model giving us intuitional understanding for mode couplings induced by few-mode fiber connections.

中文翻译：

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弱耦合少模光纤中多个连接引起的模式耦合统计

摘要 我们数值研究了在弱耦合模分复用 (MDM) 系统中由具有横向未对准的多条少模光纤连接引起的模式耦合的统计特性。对于目前可行的连接器，串扰比小于-20dB的概率随着连接数的增加而显着降低。目前可行的连接器不适用于弱耦合的 MDM 系统。为了将模串扰抑制在-20dB以下，失调偏差需要小于0.04，相当于基模模场直径的0.3%。此外，我们提出了简单的模型，让我们对少模光纤连接引起的模式耦合有直观的理解。