High-speed broadband services require optical fibres in access networks, in which multiple subscribers are connected to service providers, to satisfy the continuously growing bandwidth demand. The primitive signaling scheme used in access networks enables the use of low-cost equipment but diminishes the bandwidth available to end-users. Thus, current technology will be unable to support future broadband demands. Coherent communication systems offer significantly improved power- and bandwidth-efficiency, but require fundamental simplifications to become economically viable for access networks. Here, we demonstrate a promising simplified coherent receiver exhibiting a robust performance against polarisation fluctuations over an installed fibre network. It enables the realisation of high-order modulation formats and offers high sensitivities, achieving a four-fold increase in the supported number of subscribers and approximately doubling the transmission distance compared to the recently standardized access technology. The proposed solution indicates that digital coherent technology can be feasible and transform the access networks, enabling ubiquitous new services and applications with uncontended, multi-gigabits/user broadband connections.

中文翻译：

---

使用简化的光学相干访问收发器，在已安装的光纤上进行双向波分复用传输。

高速宽带服务需要接入网络中的光纤，其中多个用户连接到服务提供商，以满足不断增长的带宽需求。接入网中使用的原始信令方案可以使用低成本设备，但会减少最终用户可用的带宽。因此，当前的技术将无法支持未来的宽带需求。相干通信系统可显着提高功率和带宽效率，但是需要进行根本的简化，以使其在接入网上具有经济可行性。在这里，我们展示了一种有前途的简化相干接收机，该接收机在安装的光纤网络上表现出强大的性能，可抵抗偏振波动。它可以实现高阶调制格式并提供高灵敏度，与最近标准化的接入技术相比，支持的订户数量实现了四倍的增长，传输距离几乎翻了一番。所提出的解决方案表明，数字相干技术是可行的，并且可以改变接入网络，从而实现无竞争的，数千兆位/用户宽带连接的无处不在的新服务和应用。