In the next-generation flexible point-to-multipoint optical networks such as optical access systems, it is desirable for one transceiver to handle various Internet-of-Things traffic streams. A symbol rate-adaptive multiband-coherent-transceiver, that can transmit and receive wavelength division multiplexing (WDM) signals arranged at the Nyquist spacing after Nyquist spectrum shaping, achieves flexibility by changing the number of subbands (SB) and the symbol rate per SB. Band-asymmetric coherent access systems with wide bandwidth optical transceivers on the optical-line-terminal side and narrowband optical transceivers on the optical-networking-unit side have been reported for uplink and downlink transmissions. We also examined the multiband-coherent-transceiver for ultra-dense WDM signals with a narrow analog-device bandwidth and narrow SB spacing to improve cost and spectral efficiency. To the best knowledge of the authors, there is no other research on a Nyquist spectrally shaped WDM-passive optical network system that applies these two functions and flexibly changes the symbol rate per SB with a SB spacing less than the Nyquist spacing.

中文翻译：

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具有符号率自适应奈奎斯特 WDM 信号的频率封装多频带相干收发器


在下一代灵活的点对多点光网络（例如光接入系统）中，需要一个收发器来处理各种物联网流量流。一种符号率自适应多频带相干收发器，可以在奈奎斯特频谱整形后发送和接收以奈奎斯特间隔排列的波分复用（WDM）信号，通过改变子带（SB）的数量和每个SB的符号率来实现灵活性。已经报道了用于上行链路和下行链路传输的带不对称相干接入系统，其在光线路终端侧具有宽带光收发器，在光网络单元侧具有窄带光收发器。我们还检查了用于超密集 WDM 信号的多频带相干收发器，该信号具有窄模拟设备带宽和窄 SB 间距，以提高成本和频谱效率。据作者所知，还没有其他关于奈奎斯特光谱形状的 WDM 无源光网络系统的研究能够应用这两种功能，并以小于奈奎斯特间距的 SB 间距灵活地改变每个 SB 的符号率。