How to determine the quality of a PLC splitter?

by http://www.fiber-mart.com

There are five main specifications that are outlined in this standard. The following section outlines each of the specification and their importance for a fully functional optical splitter.
1. Optical Bandpass
For a fiber optic network, there are six nominal optical bandpass ranges.
A PON system has a downstream transmission (data sent from a server to a user) using the 1490nm wavelength while the upstream transmission (data sent from a user to a server) is a 1310nm wavelength. In addition, there needs to be consideration for any requirement for RF video overlay and network testing/maintenance. RF video overlay is generally transmitted through the 1550nm wavelength.
According to the ITU L.41 recommendation, the 1550nm or 1625nm wavelength is used for network for testing and surveillance. With these considerations, the required optical band needs to be determined.
The standard operating wavelength for a PON splitter is the 1260-1650nm which covers most of the optical bands.
The optical bandpass can be tested by connecting the optical splitter to an optical spectrum analyzer with a high powered light source having a central wavelength of the required bandpass. The attenuation across the required bandpass shall meet the splitter requirements.
2. Optical insertion loss
The optical splitter is the component with the largest attenuation in a PON system. The optical insertion loss is the loss of an optical signal resulting from the insertion of a component such as connector or splice in an optical fiber system. In order to conserve the power budget of a PON system, the insertion loss from the splitter needs to be minimized.
Based on the GR-1209 standard, the maximum allowable insertion loss for an optical splitter used in a PON system can be determined by using the calculations outlined in the below table.
1×N Optical Splitter 0.8 + 3.4 log2N
2×N Optical Splitter 1.0 + 3.4 log2N
Note: ‘N’ denotes the number of output ports.
The insertion loss is tested by using a light source and power meter(or) by using an insertion loss meter.The reference power level is obtained and each of the output port of the optical splitter is measured.
3. Optical return loss
The return loss is the loss of power in the light signal returned or reflected by a discontinuity in an optical fiber or transmission line. A high return loss reduces the power reflected back to the transmitting port thus minimizing noise which may result in a system power penalty.
The return loss is tested by using a return loss meter. The input port of the splitter is connected to the return loss meter and all the output ports are connected to a non-reflective index matching gel.
4. Uniformity
Uniformity is the maximum insertion loss value between one input port and any two output ports or between two input ports and one output port. This requirement ensures that for a PON system, the transmission power at each splitter output port is the same, thus simplifying the network design.
Custom optical splitters with non-uniform coupling ratio can be manufactured for specific network deployment. In such a situation, this criteria is not applicable. The usage of a non-uniform splitter in a PON system increases the complexity in testing, design and maintenance while reducing the network flexibility.
The uniformity of the splitter can be determined by referring to the results from the insertion loss test to ensure that the difference between the highest loss and the lowest loss is within the acceptable uniformity value (≤0.5 dB).
5. Directivity
Directivity is the fraction of power transferred from one input port to another input port or from an output port to another output port. For a 2×N optical splitter, when light is injected into one of the input ports, light does not only propagate out of the output ports. Some of the light propagates back through the second input port. Similarly, when light is injected into one of the output ports, some of the light propagates back through the other output ports.
In a bidirectional transmission system such as a PON, directivity is important to reduce the power back to the transmitting port to reduce signal cross talk. In addition, a high directivity value will also cause a higher insertion loss due to the loss in optical power. So it is important to reduce the directivity as much as possible.
Directivity can be measured in a manner similar to the insertion loss test. However, the light source and power meter are connected to each of the input ports of two output ports.

Advantages and Disadvantages of FBT Splitter and PLC Splitter

Fiber optical splitter is also known as “non-wavelength selective optical branching device”. It is a fiber optic device used to achieve a particular band optical signal power splitter and redistribution.
Optical splitter can be used as a stand-alone device in the OLT node, the light distribution point and the FTTH point. It can also be placed in the central office wiring facilities, the light distribution points and FTTH points within the facility (integrated design or plug-in).
In accordance with the production process, optical splitters are divided into Fused Bi-conical Taper (FBT Splitter) and Planar Lightwave Circuit (PLC Splitter).
FBT Splitter (FBT Coupler)
Fused Bi-conical Taper technique is tied to two or more fibers, and then melted in a cone machine, pull tensile and real-time monitoring of changes in splitting ratio, the splitting ratio to meet the requirements after the end of the melt stretching, and wherein one end of a fiber optic reserved ( The remaining cut off) as the input terminal and the other end a multitude of road outputs. Mature tapering process can only pull 1 × 4. 1 × 4 or more devices, with a plurality of 1 × 2 connected together. Then the overall package in the splitter box.
Advantages
(1) pull taper coupler over twenty years of history and experience, many equipment and processes simply follow the only development funds only a few of the PLC tenth or hundredth of a few
(2) Raw materials only readily available quartz substrate, fiber optics, heat shrink tubing, stainless steel pipe and less plastic, a total of not more than $ 1. Investment in machinery and equipment depreciation costs less, 1 × 2,1 × 4 and other low-channel splitter low cost.
(3) splitting ratio can be real-time monitoring, you can create unequal splitter.
Disadvantages
(1) Loss of light sensitive wavelength ships according to the wavelength selection device, in this triple-play during use is a fatal defect, since the triple play of light transmitted signal 1310nm, 1490nm, 1550nm, and other multiple-wavelength signal.
(2) poor uniformity, 1×4 nominal about 1.5dB away, 1 × 8 or more away from larger, can not ensure uniform spectroscopic, which may affect the overall transmission distance.
(3) Insertion loss varies with temperature variation is greater (TDL)
(4) multi-demultiplexer (e.g., 1 × 16,1 × 32) volume is relatively large, the reliability will be reduced, the installation space is restricted.
PLC Splitter
Planar waveguide technology is the optical waveguide branching device with a semiconductor production process. The branching function is completed on the chip. On one chip to achieve up to 1X32 splitter, then, at both ends of the chip package input terminal and an output terminal respectively coupled multi-
Channel optical fiber array.
Advantages
(1) The loss of transmission is not sensitive to the wavelength of light, to meet the transmission needs of different wavelengths.
(2) spectroscopic uniform signal can be uniformly allocated to the user.
(3) compact structure, small size, can be installed directly in the existing junction box, no special design leave a lot of space for installation.
(4) only a single device shunt channel can achieve much more than 32 channels. (5) The multi-channel, low cost, stars ones more and more obvious cost advantages.
Disadvantages
(1) Device complex production process, high technical threshold, the chip is several foreign companies to monopolize domestic bulk package production companies only Borch rarely several.
(2) relative to the higher cost of Fused Splitter more at a disadvantage, especially in the low channel splitter.

How to choose the PLC splitter correctly?

by http://www.fiber-mart.com

PLC splitter is a simple passive component which plays an important role in the applications of technologies like GPON, EPON and BPON. It allows a strand of fiber optic signal being equivalently splitted into several strands of optical signal, which can support a single network interface to be shared by many subscribers. When selecting it, split ratios should always be considered. However, with the network cabling environment becoming increasingly complex, various PLC splitters with different package form factors are being invented. Now the package form factor of it is also a key factor to be considered. This post will introduce the most commonly used PLC splitters in different package form factors for your reference during selection.
Bare Fiber PLC Splitter
Bare fiber PLC splitter is commonly used in FTTx projects. It leaves bare fiber on all its ends. Thus, they can be spliced by network engineer freely according to the applications. Meanwhile, it requires the least space during cabling. They can be installed in fiber optic splicing closure easily to provide FTTH signal distribution.
Fanout PLC Splitter
Fanout PLC splitter generally uses 0.9mm buffer fiber, added with a length of ribbon fiber terminated with fanout kit behind the PLC split chip. The splitter ratios of it also come in various types. The following picture shows a 1:8 fanout version which is terminated with SC/APC connectors.
ABS PLC Splitter
ABS PLC splitter uses ABS plastic box to holding the splitter chip. The inbound fibers and distribution fibers are arranged on the same plate of this ABS box, which can provide easier and more flexible cabling. Except providing reliable protection, it can also be installed in a variety of boxes or enclosures. It is very commonly to install a it in a standard 19-inch rack unit.
LGX Box PLC Splitter
LGX Box PLC splitter looks like a MTP LGX cassette. It houses the whole splitter inside a metal box and leave fiber optic adapters for both inbound fibers and distribution fibers on its front panel. The LGX splitter can be used stand alone or be installed in the standard rack unit or fiber enclosures for better cabling.
Rack Mount PLC splitter
Rack mount PLC splitter is designed to meet the requirement of high cabling density for data centers or server room. It can be firmly installed on the data center or server racks. It is an ideal solution for high density cabling environment. Rollball can provide PLC splitter ports up to 64 in 1U 19-inch rack.

Differences Between FBT Splitter and PLC Splitter

by http://www.fiber-mart.com

Nowadays, with the further popularization of the optical fiber communication, fiber optic splitter plays an increasing significant role in many of today’s optical network topologies. Although there are variations of splitter types, the two most commonly deployed splitters are FBT (Fused Biconical Taper) splitter and PLC (Planar Lightwave Circuit) splitter. So, when you deploy your network, what kind of splitter you should choose may be a problem for you. And in order to solve this problem, this paper will give you a detailed introduction of differences between FBT splitter and PLC splitter.
Definition of FBT Splitter and PLC Splitter
Before you get to know the features of them, first you should know what them are. Next, each splitter will be introduced.
FBT Splitter – FBT is a traditional technology that two fibers are typically twisted and fused together while the assembly is being elongated and tapered. The fused fibers are protected by a glass substrate and then protected by a stainless steel tube, typically 3mm diameter by 54mm long. FBT splitters are widely accepted and used in passive optical networks, especially for instances where the split configuration is not more than 1×4. The slight drawback of this technology is when larger split configurations such as 1×16, 1×32 and 1×64 are needed.
PLC splitter – A PLC splitter is a micro-optical component based on planar lightwave circuit technology and provides a low cost light distribution solution with small form factor and high reliability. It is manufactured using silica glass waveguide circuits that are aligned with a V-groove fiber array chip that uses ribbon fiber. Once everything is aligned and bonded, it is then packaged inside a miniature housing. PLC Splitter has high quality performance, such as low insertion loss, low PDL (Polarization Dependent Loss), high return loss and excellent uniformity over a wide wavelength range from 1260 nm to 1620 nm and have an operating temperature -40°C to +85°C.
Feature Comparison of FBT Splitter and PLC Splitter
In the past few years, splitter technology has made a huge step forward, especially the PLC splitter technology. This situation resulted in that PLC splitter has become a higher reliable type of device compared to the traditional FBT splitter. Although being similar in size and appearance, the internally technologies behind these types vary, thus giving service providers a possibility to choose a more appropriate solution.
Operating Wavelength – As is mentioned above, PLC splitter can provide a range of operating wavelength from 1260 nm to 1620 nm. But FBT splitters only support three wavelengths (850/1310/1550 nm) which makes these devices unable to operate on other wavelengths.
Operating Temperature – Commonly, FTB splitter is to a high extent temperature sensitive, providing a stable working range of -5 °C to 75 °C. While PLC splitter operates at wider temperature range (-40 °C to 85 °C), allowing its deploying in the areas of extreme climate.
Split Ratio – The split ratio of FBT splitter is 1:8 and it can be higher with higher failure rate. The split ratio of PLC splitter can go up to 64, which is equal to all branches, thus providing a high reliability.
Cost – FBT splitter is made out of materials that are easily available, for example steel, fiber, hot dorm and others. All of these materials are low-price, which determines the low cost of the device itself. PLC splitter manufacturing technology is more complex. It uses semiconductor technology (lithography, etching, developer technology) production, hence it is more difficult to manufacture. Therefore, the price of this device is higher.
Conclusion
In a word, Compared with FBT splitter, the capacity of PLC splitter is better, but costlier than the FBT splitter in the smaller ratios. You can choose it according to your requirements. fiber-mart.com offers both FBT splitter and PLC splitter with good quality and low price. Whether in FTTx systems or in traditional optic network, fiber-mart.com splitter can help you to maximize the functionality of optical network circuits.

Understanding of FTTx Network

FTTx technology plays an important role in providing higher bandwidth for global network. And FTTx (fiber to the x) architecture is a typical example of substituting copper by fiber in high data rate traffic.

FTTx technology plays an important role in providing higher bandwidth for global network. And FTTx (fiber to the x) architecture is a typical example of substituting copper by fiber in high data rate traffic.According to the different termination places, the common FTTx architectures include FTTH, FTTB, FTTP, FTTC and FTTN. This article will introduce these architectures respectively.

 

What is FTTx Network?

FTTx, also called as fiber to the x, is a collective term for any broadband network architecture using optical fiber to provide all or part of the local loop used for last mile telecommunications.

 

 

Different FTTx Architectures

FTTP: fiber-to-the-premises, is a loosely used term, which can encompass both FTTH and FTTB or sometimes is used a particular fiber network that includes both homes and businesses. It depends on how the context is used and specific location of where the fiber terminates. FTTP can offer higher bandwidth than any other broadband services, so operators usually use this technology to provide triple-play services.

FTTH: as indicated by the name fiber-to-the-home, fiber from the central office reaches the boundary of the living space, such as a box on the outside wall of a home. Once at the subscriber’s living or working space, the signal may be conveyed throughout the space using any means, such as twisted pair, coaxial pair, wireless, power line communication, or optical fiber. Passive optical networks (PONs) and point-to-point Ethernet are architectures that deliver triple play services over FTTH networks directly from a operator’s central office.

FTTB (fiber to the building) — Fiber terminates at the boundary of the building. A fiber cable in FTTB installation goes to a point on a shared property and the other cabling provides the connection to single homes, offices or other spaces. FTTB applications often use active or passive optical networks to distribute signals over a shared fiber optic cable to individual households of offices.

FTTC( fiber-to-the curb or -cabinet), is a telecommunication system where fiber optic cables run directly to a platform near homes or any business environment and serves several customers. Each of these customers has a connection to this platform via coaxial cable or twisted pair. The term “curb” is an abstraction and just as easily means a pole-mounted device or communications closet or shed. Typically any system terminating fiber within 1000 ft (300 m) of the customer premises equipment would be described as FTTC. A perfect deployment example of FTTC is a DLC/NGDLC (digital loop carrier) which provides phone service.

FTTN (fiber to the node) — Fiber terminates in a street cabinet, which may be miles away from the customer premises, with the final connections being copper. One of the main benefits of FTTN is the ability to deliver data over more efficient fiber optic lines, rather than other fiber optic lines with greater speed restriction

 

Conclusion

The advent of FTTx network is of great significance for people around the world. As it has a higher speed, costs less, and carries more capacity than twisted pair conductor or coaxial cables. Fiber-Mart can provide customized service ,pls don’t hesitate to contact me at service@fiber-mart.com

Differences Between FBT Splitter and PLC Splitter

In future fiber networks, splitters provide capabilities that help users maximize the functionality of optical network circuits.according to different manufacture technologies, fiber optic splitters can be divided into PLC splitter and FBT splitter.

In future fiber networks, splitters provide capabilities that help users maximize the functionality of optical network circuits.according to different manufacture technologies, fiber optic splitters can be divided into PLC splitter and FBT splitter.

What is Fiber Optic Splitter?

Fiber Optic splitter is suitable for a fiber optic signal to be decomposed into mufti-channel optical signal output.

Fiber splitters are comprised of three fibers – two fiber legs on one side that overlap inside a junction with a third fiber at the common end. The fiber type used in each leg is typically the same, but can also be custom configured to have different fiber core diameters or wavelength ranges. fiber splitters are good for mixing light from two different locations and delivering it through a single fiber to a spectrometer or sample.  This ability can be used to combine illumination from two different light sources, or to mix light collected from two different sampling points before delivery to a spectrometer.

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Optical Splitter is used to split the fiber optic light into several parts at a certain ratio. It is an important component used in Passive Optical Network (PON), therefore also called PON Splitter. There are mainly two kinds of PON splitters: one is the traditional fused type splitter known as FBT Coupler or FBT WDM splitter, which features competitive price; the other is the PLC Splitter based on the PLC (Planar Lightwave Circuit) technology, which has a compact size and suits for density applications. fiber optic splitter, also known as a beam splitter, is based on a quartz substrate of an integrated waveguide optical power distribution device, similar to a coaxial cable transmission system. The optical network system also needs to be an optical signal coupled to the branch distribution. In which requires the fiber optic splitter is one of the most important passive devices in the optical fiber link, is optical fiber tandem device with many input terminals and many output terminals, especially applicable to a passive optical network (EPON, GPON, BPON, FTTX, FTTH etc.) to connect the MDF and the terminal equipment and to achieve the branching of the optical signal.

FBT Splitters

FBT splitter is made out of materials that are easily available, for example steel, fiber, hot dorm and others. All of these materials are low-price, which determines the low cost of the device itself. Fused Biconical Taper (FBT) is used for splitting or combining optical signals and is tied to two or more fibers, and then melted in a cone machine, pull tensile and real-time monitoring of changes in splitting ratio, melt tensile splitting ratio to meet the requirements end, wherein one end of a fiber optic reserved ( The remaining cut off) as the input terminal and the other end a multitude of road outputs. Mature tapering process can only pull 1 × 4. 1 × 4 or more devices, with a plurality of 1 × 2 connected together. Then the whole package in the splitter box. The splitting or coupling ratio is controlled and can be modified upopn costumer request as well as the amount of splitting ports. The FBT coupler supports dicrete wavelength window.

fbt.jpg

PLC Splitters

PLC splitter manufacturing technology is more complex. It uses semiconductor technology (lithography, etching, developer technology) production, hence it is more difficult to manufacture. PLC refers to planar lightwave circuit. As a micro-optical device, PLC splitter uses an optical chip to split the input signal into various outputs. At the edge of the chip, there is a light circuit in ribbon form mounted on a carrier and fibers. PLC splitter typically adopts silica glass as the material of lightwave circuit and accepts different types of polished finishes. The substrate, waveguide and lid are three basic layers of the PLC splitter. For different applications, PLC splitters can be further categorized into different types including bare PLC splitters, blockless PLC splitters, ABS PLC splitters, LGX box PLC splitters, mini plug-in type PLC splitters, tray type PLC splitters and 1U rack mount PLC splitters.

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Differences Between FBT Splitter and PLC Splitter

In this part, we will take a look at the main differences between FBT splitter and PLC splitter , which are listed in following.

 

PLC_Table.PNG

PLC splitters are optimal split applications since they facilitate the construction of many optical circuits in a compact size. although the outer appearance and size of FBT and PLC fiber splitter seem rather similar, their internal technologies and specifications differ in various ways. Fiber-Mart provides both PLC splitters and FBT coupler splitters for EPON/GPON Systems.any question pls not hesitate to contact us. E-mail:service@fiber-mart.com