Improvement on the Optical Fiber Connection Technology in the optical fiber Access Network

After a long period of development, many users are familiar with the optical fiber connection technology in the optical fiber access network. Here I will share my personal understanding and discuss with you. The development of optical fiber connection technology (such as splicing technology to replace the crimping technology) makes the application of optical fiber more and more common in cabling, so the use of optical fiber distribution equipment is more and more extensive. For example, the on-site fusion-free technology can make the average fiber end connection per core less than 1 minute, and the use of a line-free express distribution frame can reduce tool costs and maintenance costs.

PCB-based wiring technology

With the development of optical interface technology, the industry has gradually established in the electrical PCB (Printed Circuit Board) the current Optical Distribution Technology, optical printed circuit board technology, optical surface installation technology, and the modular design and installation technology of the same optical, optical, and electrical devices improve the automation of the wiring process, this avoids the high technical requirements of manual wiring and easily reduces the quality of the line.

Use of Band Optical Cable

The core of the trunk cable can be easily and flexibly networked as long as it is connected to various optical junction boxes and wired. However, excessive fiber Jumpers may cause deterioration of line indicators and increase investment. In order to ensure flexible scheduling and Protection Investment of the core, three types of Core Cables can be planned: shared core, exclusive core, and direct core, this makes wiring very convenient and easy to maintain.

OADM and OXC

Currently, most fiber-optic access networks are connected to man through fiber distribution frames. This manual configuration method is available in large-scale optical transmission networks, it seriously affects the service allocation time, the response time to network business models and faults, and increases the operation overhead, however, it does not take full advantage of the optical multiplexing technology. Automatically reconfigure the optical network, automatically establish optical connection, shorten the specified service time, speed up the fault response time, establish level services, and develop new value-added services on this basis, is the development goal of the optical fiber access network. As DWDM gradually advances to the edge of the network, one day, the optical fiber access network will gradually adopt optical plug-and-play multiplexing devices (OADM) with uplink and downlink connections in units of wavelength) the optical fiber cross-connection device (OXC) implements optical switching and optical routing. The functions of the optical fiber distribution device will be integrated into OADM and OXC and eventually replaced.

Optical Cable Distribution Method Selection

General principles: the selection of Optical Cable routes and the determination of core numbers should be guided by the overall urban development and construction plan, and based on business demand prediction and user distribution. The network structure of the optical fiber access network determines the choice of the wiring method to a certain extent. The network structure of the optical fiber access network varies depending on the business type, range, node Location Distance, and regional economic capacity of the Access Node, the construction of the optical fiber access network is generally to first build a trunk cable network, determine the network structure of the trunk network, and then develop the distribution network according to the actual situation of the specific area. Build a wiring network only when there are business needs and access the backbone network of the nearest optical fiber network. The accuracy of business prediction has a great impact on the operability of optical cable planning. However, due to the long service life of the optical cable and the limitation of various factors on service prediction, during the design of the optical cable network, the user's optical cable cabling method should be flexibly used according to the local conditions to achieve the intended purpose. The long-term stability of the trunk cable, the flexibility of the cable, and the reliability and economy of the overall network should also be considered when selecting the user's optical cable distribution method. The choice of the wiring system needs to consider the medium and long-term needs to ensure that the optical fiber can be flexibly and conveniently stored, so that the capacity can be increased by adding modules in the future business development.

Selection policy: in areas with scattered users and stable requirements, or for leased line users with high confidentiality requirements, direct wiring can be considered. For example, in the initial phase of users' optical cable network construction, due to high cable prices, small demand for high-speed broadband services, and scattered users, direct cabling can be used for the construction of a small-scale user optical cable network from the target Bureau to the remote node. In addition, the telephone system will remain an effective communication tool for a long time in the future, and the telephone business volume will remain relatively stable for a certain period of time; at this time, the design from the Exchange Board to the trunk lines of various buildings using optical fiber direct wiring has the advantages of simple wiring and economic advantages. When the number of users in a region is relatively unstable, or the number of users is relatively small and the user location is relatively scattered, some re-wiring can be used to increase the utilization rate of the core cable and reduce investment. Subsidy wiring can be used in areas with slow user development and even density.

In order to improve the flexibility and flexibility of the wiring network, the wiring method should be promoted. The ring-type junction wiring method is good in terms of flexibility and reliability, and should be preferred when economic conditions permit. This network structure is mainly used in large and medium-sized cities with fast business growth, a wide variety of users, and can form a ring-type optical fiber access network structure containing multiple bureaus.

In urban suburbs or small towns, due to low user density and simple business types, users' business needs are unclear at the early stage of access network construction, making it difficult to make accurate business forecasts, large-scale cable network construction may make investment unable to make full use of the benefits for a long period of time, therefore, the construction of Fiber-to-building and fiber-to-residential areas can be used for users with business needs and areas suitable for fiber-to-access networks, the self-healing Ring can also be used to improve network security when conditions permit. This network structure is characterized by determining the route and core numbers of optical cables based on specific user requirements, rather than dividing trunk and wiring cables. Therefore, in the initial stage, a star or tree structure should be used to establish a ring-type hybrid network gradually when the business and users develop.

Due to environment and installation factors, the optical fiber access network wiring is directly related to the stability of the network. Therefore, the wiring problem becomes an important issue for enhancing the network robustness. With the large-scale construction of the optical fiber access network, the problem of optical fiber cabling has attracted more and more attention from the builders. Starting from improving the accessibility, usage, and stability, the optical fiber access network construction adopts the wiring method of the main fixed distribution area. At the same time, various wiring technologies should be comprehensively used as needed to improve the overall benefits of the optical fiber access network. For example, the re-connection of fiber-optic devices in the transfer zone is conducive to play the role of the original optical fiber or solve the urgent need. With the continuous development of fiber access networks and the development of fiber cabling and related technologies, we should track the new development of fiber cabling systems, adopt new technologies and technologies in a timely manner, and improve the technical content and intelligence of cabling systems, this facilitates the smooth evolution of access networks to all-optical networks and optical cabling to optical crossover connections.