Full-Duplex Self-Recovery Optical Fibre Transport System Based on a Passive Single-Line Bidirectional Optical Add/Drop Multiplexer

Abstract

A full-duplex self-recovery optical fibre transport system is proposed on the basis of a novel passive single-line bidirectional optical add/drop multiplexer (SBOADM). This system aims to achieve an access network with low complexity and network protection capability. Polarisation division multiplexing technique, optical double-frequency application and wavelength reuse method are also employed in the transport system to improve wavelength utilisation efficiency and achieve colourless optical network unit. When the network comprises a hybrid tree-ring topology, the downstream signals can be bidirectionally transmitted and the upstream signals can continuously be sent back to the central office in the reverse pathways due to the remarkable routing function of the SBOADM. Thus, no complicated optical multiplexer/de-multiplexer components or massive optical switches are required in the transport system. If a fibre link failure occurs in the ring topology, then the blocked network connections can be recovered by switching only a single optical switch preinstalled in the remote node. Simulation results show that the proposed architecture can recover the network function effectively and provide identical transmission performance to overcome the impact of a breakpoint in the network. The proposed transport system presents remarkable flexibility and convenience in expandability and breakpoint self-recovery.

Highly Reliable Metro-Access Network Based on a Dual-Fiber Ring Architecture and Optimized Protection Mechanisms

“…These are usually contradictory because the improvement of reliability depends on backing up or sharing the existing resources and thus increasing the additional construction cost. In contrast to previous studies based on pure optical protection [9]- [13], [15], [16], [33], [34], [40], [48] and based on wireless protection [21]- [25], [29], [30], our study can enhance the reliability performance for metro-access optical networks based on the WDM technique while reducing the additional construction cost and the expenditure of each subscriber. For example, previous studies [21]- [23] based on survivable WOBAN architecture have the limitation that they are not suitable for fault scenarios that require recovering significant losses of data, such as a fault in the feeder segment and even a fault in the distribution section of the WDM network.…”

“…This scheme can achieve network reliability of more than 99.9999%, which is superior to that of some existing schemes [9], [10], [12], [13], [15], [33], [40], [48]. Furthermore, in contrast to [11], [16], [30] and [34], the proposed scheme can support protection from more types of faults, including single-fiber faults, dual-fiber faults and multifiber faults. For instance, in [11] and [30], the network will not work when there are two fibers broken in the feeder segment.…”

“…For instance, in [11] and [30], the network will not work when there are two fibers broken in the feeder segment. In addition, in [16] and [34], if two faults occur in the ring section of the network, all the nodes located between the two positions of the faults will not communicate with the CO. On the other hand, in our scheme, since the additional construction cost for the protection of the feeder segment is shared by the large number of users of the overall network [17], the optical protection approach adopted in this segment can greatly enhance the reliability performance while not needing to introduce a high extra cost for each subscriber. Moreover, the cost of establishing microwave connectivity and its yearly spectrum leasing fee are only around $150 and $200, respectively [30], which is much cheaper than the pure optical protection approach.…”

“…To address the above two disadvantages, as a promising candidate for large-capacity wireless access scenarios, although the development of survivable WOBAN architectures based on microwave or millimeter-wave (mmWave) techniques has been discussed extensively in the existing literature, most are restricted to focusing only on single protection techniques, e.g., wireless protection for the front end [27]- [28] or pure optical protection for the backhaul [33]- [34]. Thus far, very little research has been carried out on integrating optical and microwave or mmWave protection to provide more effective and flexible protection, and thus, these existing survivability studies also feature some of the unavoidable aforementioned defects belonging to a certain group of protection method.…”

Design of a 1x4 Optical Power Divider Based on Y-Branch Using III-Nitride Semiconductor

“…The term "passive" refers to devices that do not require any optical-to-electrical conversion or vice versa to function. The passive components in optical communications include optical connectors, circulators, add/drop multiplexers, switches, and splitters/dividers [1][2][3][4]. Optical power dividers play an important role in dividing and combining optical signals in optical communication.…”