排序方式: 共有177条查询结果,搜索用时 347 毫秒
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介绍了用户接入网的发展, 光纤用户接入设备的组成和功能, 光纤用户接入设备与交换机远端用户模块、用户数字环路设备的比较,以及光纤用户设备引入对本地网建设的影响。 相似文献
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余辰东 《电信工程技术与标准化》2017,(3)
PON网络中的弱光问题随着FTTX业务发展(远距离、大分光比应用)变得越来越严重。通过对弱光产生原因的分析,梳理了影响光功率预算的主要因素。基于EPON扩展OAM/GPON OMCI协议,通过比较标准定义与实际应用,报告了ONU光功率的检测方法以及对应的弱光故障定位策略。结合工程应用总结了弱光问题防护与解决的几种方法。 相似文献
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Effects of Upstream Incoherent Crosstalk Caused by ASE Noise from Tx‐Disabled ONUs in XG‐PONs and TWDM‐PONs 下载免费PDF全文
A large incoherent crosstalk (IC) caused by amplified spontaneous emission (ASE) noise power from Tx‐disabled optical network units and a differential path loss has been shown to degrade upstream transmission performance in time‐division multiplexing passive optical networks. This paper considers the IC‐induced power penalty of an upstream signal both in an XG‐PON and in a TWDM‐PON. We investigate the degradation of the extinction ratio and relative intensity noise through a simulation and experiments. For the XG‐PON case, we observe a 9.6 dB difference in the level of ASE noise power from Tx‐disabled ONUs (hereafter known simply as ASE noise) between our result and the ITU‐T XG‐PON PMD recommendation. We propose an optical filtering method to mitigate an IC‐induced power penalty. In the TWDM‐PON case, the IC‐induced power penalty is naturally negligible because the ASE noise is filtered by a wavelength multiplexer at the optical line terminal. The results provide design guidelines for the level of ASE noise in both XG‐PONs and TWDM‐PONs. 相似文献
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Naresh Kumar 《Optik》2014
Gigabit passive optical networks (GPON) provide a capacity boosts in both the total bandwidth and bandwidth efficiency through the use of larger variable-length packets in Passive Optical Networks technology. In this paper, we have described a purely-passive GPON compatible reach extender using distributed Raman amplification and reported the improved investigation through implementation of a square root module by a distance of 60 km at data rate of 2.5 Gbps. An efficient improvement in Q factor is achieved with square root module, which further helps in increasing the length of GPON. 相似文献
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本文综述了DAR成色剂的研究进展,特别是DAR成色剂的结构和作用机理. 相似文献
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通过阐述以太网无源光网络(EPON)系统信道传输数据方式以及动态带宽分配的工作原理,进一步研究了动态带宽分配算法(DBA)在EPON系统中的应用。提出一种基于服务质量(QoS)的EPON系统动态带宽分配机制,该机制根据不同业务的优先级和动态带宽分配算法,灵活地分配上行带宽,提高了带宽利用率,改善了服务质量。 相似文献
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在介绍WD-MPON方案需求的基础上,给出再调制方案来获得无色高速率WDM-PON提高色散偏差,提出了基于一种反射式半导体光放大器再调制方案,描述了方案的实现原理。仿真结果表明,在相同的输入条件下,实现ONU无色化的技术方可以提高色散偏差的容忍,提高了眼图张开度,系统有一定的实用意义。 相似文献