Design and Application of FTTH Optical Fiber Network

After nearly 10 years of development, the technology of FTTH application has been very mature, and FTTH products have been commercialized, which have laid a solid foundation for the development of FTTH. The emerging new technologies, in turn, have further contributed to the prosperity of the FTTH market.

The main new technologies in the FTTH market include nanostructured bend-resistant optical fibers, optical fiber mechanical termination connectors, and the development of EPON technology. At present, these technologies have been commercialized by Corning, Huawei, 3M, UT Starcom and other communication companies, and are widely used in the FTTH optical fiber network around us.

In this paper, four different solutions are designed in combination with the main building types, which also cover the specific applications of mainstream technologies such as bend-resistant optical fiber, mechanical termination, and EPON.

The performance of the Uni Cam connector in high-speed digital transmission and analog video transmission systems is confirmed; for the index matching fluid widely used in mechanical termination joints, this paper also confirms that its service life can meet our requirements. Finally established the mainstream position of optical fiber cold splicing technology in FTTH.

In the FTTH market, although there are many participants including real estate developers, telecom operators, communication product manufacturers, scientific research institutes, government informatization promotion departments, independent investors, etc., but the large-scale promotion and popularization of FTTH, telecom operators are still Backbone. With the development of technology and society, the strong alliance of telecom operators and radio and television providers will be an inevitable choice.

FTTH (Fiber to the Home), The Ultimate Guide

The optical fiber access network mainly adopts the PON (passive optical network) centralized optical splitting topology, and uses the optical splitter to distribute the optical signal and provide services for multiple users at the same time. Optical cables used in FTTH application networks are divided into feeder optical cables, distribution optical cables and home optical cables according to their positions in the network.

In a FTTH centralized optical distribution network, each user converts optical fiber signals into electrical signals through an ONT optical network terminal, including data (RJ45) interface, voice (RJ11) interface and video (coaxial cable) interface, in the user’s room It is connected to each equipment terminal through various copper cables, and the home optical cable is generally terminated by optical fiber cold splicing joints.

The home optical cable generally uses two-core leather cable, and the home optical cable and the distribution optical cable are terminated with optical fiber cold splices, and then connected through an adapter.

The feeder fiber optic cable uses the optical splitter to transmit the optical signal to the distribution fiber optic cable, and finally the feeder fiber optic cable is directly connected to the central computer room of the community. Connect to a video network.

Feeder cables, distribution cables and home cables generally use G657 or bend-resistant fibers with a small bend radius.

Compared with the distributed optical splitting network, the centralized optical splitting architecture provides the following advantages:

Minimize the initial investment of optical splitters in the network, making it possible to “invest while growing”;

In the case of medium to low order rates, the splitter output port utilization is higher;

Network fault location and troubleshooting are simpler, saving labor costs;

Fiber loss budget is improved;

Due to the above reasons, the centralized optical splitting architecture has become the most widely used PON networking method today.

Here we mainly discuss two application solutions, including apartment solutions and villa solutions.

Learn more about: What is the Difference Between EPON and PON?

Since older apartments will not implement FTTx in the short term, we do not consider them here. (Approximately 50-60% of the number of dwelling units).

In an apartment building application environment, we faced numerous challenges in implementing FTTx:

Negotiating and coordinating with builders/owners hindering operators when entering a building/user unit.

Ensure that the direction of the optical cable does not produce additional losses;

Install ducts and conduits to control the turning radius of the fiber.

Prevent fiber damage during installation.

Sufficient space to ensure that the turning radius of the fiber is within specification.

In order to adapt to the turning radius of the optical fiber, the installation of additional hardware and pipes affects the aesthetics of the building, which is not easy for the owner to accept.

Different from the metropolitan area network and long-distance trunk line originally constructed by operators, FTTH application network requires lower construction cost, simpler network design, faster deployment speed, and better return on investment.

First of all, in order to reduce the overall installation cost to increase ROI and expand the economically applicable market scope: we need to reduce labor and material costs for protecting optical fibers; reduce labor time; reduce labor levels without professional labor.

Secondly, in order to improve the speed and reliability of installation to reduce the initial investment, quickly increase the number of customers and pay back the investment: we need to reduce the risk of fiber damage and provide the same strength and operational characteristics as copper cables;

Minimize the amount of engineering on the construction site, use the factory’s customized products as much as possible, and reduce the variety of products.

The last is to reduce the impact on the aesthetics of the building, and it is easier to negotiate with the property and the owner: the size of all products needs to be reduced; the fiber optic cable to the home can be laid along a compact route.

For apartments on different floors, we mainly use three different schemes.

FTTX Optical Fiber Network Construction Solution

The floors of multi-storey apartments are generally 4-7 floors. The characteristic is that there is no elevator in the building, no equipment shaft, and no public computer room facilities in the community.

Therefore, in each building unit, for the application of FTTH, we set up a small indoor or indoor and outdoor general optical cross-connect box, a two-core feeder cable is terminated here, through an optical splitter and a leather cable The optical cable directly sends the optical signal to each household. The optical splitter can flexibly choose 1X32, 1X16 or 1X8 and other optical splitter modules according to the number of different units. Inside the house we set up a standard 86 type wiring box.

In the small optical junction box, we use fusion splicing to terminate the household fiber optic cables from each household, and in the household, we use Uni Cam mechanical termination connectors to terminate the household fiber optic cables on-site.

The home optical cable adopts Corning’s Nano-structured Clear Curve anti-bending optical cable. The installation of the home optical cable can be accessed from outside the unit when the household needs it. The Clear Curve anti-bending optical cable can also be coiled in the wire groove when the bending radius is less than 10 mm. for future use.

The miniaturized beamsplitter is a modular plug-and-play design that requires no installation tools. We set up a standard 86-type distribution box in the household, or directly connect the optical fiber cable to the user’s ONT unit.

FTTH Cables and Their Role in Internet Connectivity

The floors of small high-rise buildings are generally 8-17 floors, which are characterized by medium height. There are elevators in the building, equipment shafts, and public computer room facilities in the community.

FTTH is applied to each building unit. We have designed 2 feeder cables, which are respectively terminated in two small indoor optical cross-connect boxes on two different floors. Each small indoor optical cross-connect box can manage multiple floors. There are multiple users. We designed a floor optical distribution box on each floor to centrally terminate the distribution optical cable and the home optical cable, and flexibly introduce the home optical cable into each user room according to the needs.

Fiber Optic Attenuator，The Ultimate Guide

The high-rise floors are generally greater than 18 floors, which are characterized by being located in the central area of the city. There are high-speed elevators, strong and weak electrical equipment shafts in the building, public equipment rooms in each building, and strong and weak electrical equipment room facilities in the community.

Due to the large number of residents in each high-rise apartment building and the higher floors, we centrally set up an indoor optical switch box in each high-rise apartment, which can support more than 200 users at most, and install modularization in the indoor optical switch box. optical splitter. We design a light distribution box for multiple floors, and we have a floor distribution box for each floor.

The feeder cable is terminated in the indoor optical transfer box, and the optical signal is sent to the main distribution cable through the optical splitter. The main distribution cable is directly connected to the floor distribution cable in the optical distribution box, and the floor distribution cable is on the floor. The optical distribution box is directly connected with each two-core home optical cable one-to-one, and finally realizes the optical signal communication with the home user ONT.

Fiber Optic Patch Cords, Everything You Need to Know

When FTTH is used in villa areas, we recommend a plug-and-play pre-connected optical cable system solution.

The floors of the villa area are generally 2-3 floors. The park area is large, and the villas are scattered. The total number of residential units is not large. There is no elevator, no shaft, and no equipment room in the villa. There are strong and weak designs in the villa area. Electricity center room.

We set up multiple local convergence point junction boxes in the villa area, which can separately manage the user fiber network in one area.

The local aggregation point junction box is connected to the feeder optical cable from the central computer room, where it is connected to the multi-user optical cable terminal through the optical splitter, and then connected to the network access point NAP (Network Access Point); or directly from the local aggregation point junction box. Connect to a network access point.

From the network access point we connect to the home’s ONT unit via a drop cable or directly via a drop cable.

The main products in the plug-and-play pre-connected optical cable system solution are factory-made, including multi-user terminal optical cables, network access points and home optical cables.

At the user end of the home optical cable, we use the Uni Cam mechanical optical fiber connector, which can quickly and flexibly install the connector on site. Even on the ceiling or ladder, we can easily install it. The installation process is not limited by space, and this This connector is not only suitable for ordinary indoor or outdoor optical cables, but also suitable for Fiber Optic Drop Cable, which is widely used in FTTH applications.

Due to the excellent system performance of the pre-connected optical cable system, the fast and convenient laying method, and the simple management and maintenance requirements, the system has been widely used in the United States, Australia and other countries.

Fiber Optic Connector, Everything You Need to Know

The FTTH market has been deployed on a large scale in many countries. Now, FTTH has become another round of communication construction climax after the 5G network construction. FTTH’s applications and services will be more exciting, and domestic users can truly enjoy the experience of high bandwidth, high security, and rich service content brought by FTTH.

With the development and progress of science and technology, there will be better communication technologies to support our FTTH fiber optic network; more services and content will be presented in our lives through the FTTH fiber optic network.

Low-loss commercial optical fiber has brought us into the real optical communication era. This communication technology has gradually become an indispensable communication medium in marine communication, intercity communication, urban communication, and backbone communication. Optical fiber has become the last resort such as FTTH fiber to the home. One kilometer is the main communication medium.