DWDM vs CWDM the most effective method

Within today’s globe associated with rigorous conversation requirements as well as needs, “fiber optic cabling” has turned into a extremely popular expression. In neuro-scientific telecoms, information middle online connectivity as well as, movie transportation, dietary fiber optic wiring is actually extremely appealing with regard to today’s conversation requirements because of the huge bandwidth accessibility, in addition to dependability, minimum lack of information packets, reduced latency as well as elevated protection. Because the bodily dietary fiber optic wiring is actually costly in order to put into action for every person support, utilizing a Wavelength Department Multiplexing (WDM) with regard to growing the capability from the dietary fiber to transport several customer interfaces is really a extremely recommended. WDM is really a technologies which brings together a number of channels associated with data/storage/video or even tone of voice methods on a single bodily fiber-optic cable television by utilizing a number of wavelengths (frequencies) associated with gentle along with every rate of recurrence transporting another kind of information. By using optical amplifiers and also the improvement from the OTN (DWDM System) coating designed with FEC (Ahead Mistake Corection), the length from the dietary fiber optical conversation may achieve a large number of Kms with no need with regard to regeneration websites.

 

CWDM VS DWDM

DWDM (Dense Wavelength Division Multiplexing) is a technology allowing high throughput capacity over longer distances commonly ranging between 44-88 channels/wavelengths and transferring data rates from 100Mbps up to 100Gbps per wavelength. Each wavelength can transparently carry wide range of services such as FE/1/10/40/100GBE, OTU2/OTU3/OTU4, 1/2/4/8/10/16GB FC,STM1/4/16/64, OC3/OC12/OC48/OC-192, HD/SD-SDI and CPRI. The channel spacing of the DWDM solution is defined by the ITU.xxx (ask Omri) standard and can range from 25Ghz, 50GHz and 100GHz which is the most widely used today. Figure – 1 shows a DWDM spectral view of 88ch with 50GHz spacing.

 

DWDM systems can offer as much as ninety six wavelengths (from 50GHz) associated with combined support kinds, and may transportation in order to miles as much as 3000km through implementing amplifiers, because shown within determine two) as well as distribution compensators therefore growing the actual dietary fiber capability with a element associated with x100. Because of its much more exact as well as stable lasers, the actual DWDM technologies is commonly more costly in the sub-10G prices, however is really a appropriate answer and it is ruling with regard to 10G support prices as well as over supplying big capability information transportation as well as online connectivity more than lengthy miles from inexpensive expenses. The actual DWDM answer these days is usually inlayed along with ROADM (Reconfigurable Optical Add Drop Multiplexer) that allows the actual creating associated with versatile remotely handled national infrastructure by which any kind of wavelength could be additional or even fallen from any kind of website. A good example of DWDM gear is actually nicely shown through PL-1000, PL-1000GM, PL-1000GT, PL-1000RO, PL-2000 as well as PL-1000TN through DK Photonics Systems.

 

CWDM (Coarse Wavelength Division Multiplexing) proves to be the initial entry point for many organizations due to its lower cost. Each CWDM wavelength typically supports up to 2.5Gbps and can be expanded to 10Gbps support. This transfer rate is sufficient to support GbE, Fast Ethernet or 1/2/4/8/10G FC, STM-1/STM-4/STM-16 / OC3/OC12/OC48, as well as other protocols. The CWDM is limited to 16 wavelengths and is typically deployed at networks up to 80Km since optical amplifiers cannot be used due to the large spacing between channels. An example of this equipment is well demonstrated by PL-400, PL-1000E and PL-2000 by DK Photonics Networks.

 

You will need to remember that the complete selection regarding DK Photonics’ products was created to help equally DWDM and also CWDM engineering through the use of specifications centered pluggable optical web template modules for instance SFP, XFP and also SFP+. The particular engineering employed will be cautiously computed every venture and also in accordance with consumer specifications regarding length, ability, attenuation and also upcoming wants. DK Photonics furthermore gives migration way coming from CWDM to be able to DWDM permitting lower access expense and also upcoming enlargement which can be looked at inside the DWDM above CWDM engineering site.

Tunable SFP+ VS. Fixed Wavelength DWDM SFP+ Transceiver

Dense wavelength division multiplexing (DWDM) is one of most important technologies to increase network transmission capacity. Early DWDM systems applied fixed wavelength DWDM transceivers and performance is good. However, as the demand for great traffic capacity keeps growing, more optical transceivers of different wavelengths are needed, leading to high cost. So how to deal with that? Tunable SFP+ arises your attention.

 

What Is Tunable SFP+

Conventional DWDM SFP+ transceivers use fixed-wavelength lasers as light sources. It means that many optical transceivers are needed for the wavelength channels in a DWDM system. While tunable SFP+ is different from fixed wavelengths modules because it applies tunable laser, which can operate at any channel wavelength, means that only one kind of transceiver is needed. Tunable lasers are now widely used as light sources in DWDM systems. Tunable SFP+ modules are only available in DWDM since CWDM grid is too wide. Tunable SFP+ optics are for the C-Band 50GHz. About 88 different channels can be set with intervals of 0.4nm, which is the 50GHz band.

For better understanding, I’ll show you a tunable module. This is a Cisco Compatible 10G DWDM C-band tunable SFP+ 50GHz Transceiver. It’s hot swappable, can support 10.3Gbps data rate up to the distance of 80km over single mode LC duplex fiber patch cable. Support 1563.86nm-1528.77nm C-band tunable wavelengths.

 

 

What you should note is that wavelengths of tunable SFP+ can be tuned only when your Cisco/Juniper/Arista/etc switch supports. If your switch only support common fixed-wavelength DWDM SFP+, you need external software to change tunable optics into certain wavelength before putting into use.

 

Why Tunable SFP+ Is Better Than Fixed Wavelength SFP+?

Fixed wavelength SFP+ are still in the market and not too many problems found in use. So you may feel puzzled about choosing tunable SFP+ or fixed wavelength SFP+ as tunable SFP+ is more expensive. The following will tell you why you need tunable optics.

 

First, save you cost. With the development of optical communication systems, the shortages of fixed-wavelength laser gradually revealed. Conventional DWDM SFP+ can lead high costs. The number of wavelengths in DWDM 50GHz has reached the hundreds. Then spare modules of each laser should be prepared for protection of the system because you don’t know which module will break down and it’s difficult to predict the number of stock in specific channels. Therefore you have to buy large quantity of DWDM SFP+ modules with fixed wavelengths. While the tunable optics are configured with different DWDM wavelengths in one module. You can select the right wavelength you need based on your optical fiber communication environment. Tunable SFP+ are typically used as “spare-optics” to save you cost.

 

Second, flexible network management. When running a DWDM network with lots of nodes, for instance, up to 80 different wavelengths, management could be a nightmare. You have to prepare couple of DWDM SFP+ optics of each wavelength and possibly in different locations. Field engineers may not access network nodes as quickly as you wish. Thus tunable optics would be a good choice. Tunable optics could be configured for a specific wavelength to support bandwidth changes as needed in optical network.

 

Third, suitable for large network capacity. As the development of increasing network transport, 400G or 1T would be the trend. Then 400G and 1T transmission formats are expected to be bulky and not fit within 50GHz spacing. These future new data rate formats require that channel spacing is flexible, that your OTN system can adapt to new rates and can re-arrange channel spacing to find place for new rates in it. Tunable optics will double the number of channels supported in this transceiver module. Upgrading to 50GHz channel spacing doubles the capacity potential in Enterprise and Metro networks.

 

Choose Tunable SFP+ in the Long Run

Tunable SFP+ are high-performance optics which can be tuned to the appropriate wavelength in seconds. The ability to function on various wavelengths has set these optics apart from fixed-wavelength DWDM SFP+. Tunable SFP+ will become popular among DWDM systems due to their ease of spare use and flexibility. Tunable SFP+ would be a powerful and invaluable transmission tool in high-speed network. At present, many engineers are using fixed wavelengths SFP+ transceivers. Some may be stopped by the tunable SFP+ price. But in the long run, you are suggested to consider tunable SFP+.

An Easy Guide to MPO/MTP Polarity

Nowadays, many data centers are migrating into the 40G and 100G transmission. To prepare for this change, MPO/MTP technology is applied to meet the requirements of high density patching. Typically, a fiber optic link needs two fibers for full duplex communications. Thus the equipment on the link should be connected properly at each end. However, high density connectivity usually requires more than two fibers in a link, which makes it more complex to maintain the correct polarity across a fiber network, especially when using multi-fiber MPO/MTP components for high data rate transmission. Therefore, many technicians would prefer to use pre-terminated MPO/MTP components designed with polarity maintenance for easier installation. This article will specifically guide you to understand the polarity of MPO/MTP products and the common polarization connectivity solutions.

 

What Is Polarity?

Keeping the right polarity is essential to the network. A transmit signal from any type of active equipment will be directed to the receive port of a second piece of active equipment and vice versa. Polarity is the term used in the TIA-568 standard to explain how to make sure each transmitter is correctly connected to a receiver on the other end of a multi-fiber cable. Once the component is connected to the wrong polarity, the transmission process will be unable to go on.

 

Structure of MPO/MTP Connector

When discussing about the polarity, MPO/MTP connector is an important component for you to know. An MPO/MTP connector has a key on one side of the connector body. There are two positions of the key – key up or key down. Key up position means that the key sits on top. When the key sits on the bottom, it is the key down position. Moreover, the fiber holes in the connector are numbered in sequence from left to right named as P1 (position 1), P2, etc. Each connector is additionally marked with a white dot on the connector body to designate the P1 side of the connector when it is plugged in. The MPO/MTP connector can be further divided into female connector and male connector. The former has no pins while the latter has two pins on the connector. The following picture shows the basic structure of MPO/MTP connector.

 

structure-of-mpo-connector

 

Connecting Methods of A, B, C

The TIA standard defines two types of duplex fiber patch cables terminated with LC or SC connectors to complete an end-to-end fiber duplex connection: A-to-A type patch cable is a cross version and A-to-B type patch cable is a straight-through version. Based on this, there are three polarity connecting methods for MPO/MTP products. Here will introduce them in details.

 

duplex-patch-cable

 

Method A is the most straight-forward method. It uses straight-through patch cords (A-to-B) on one end that connect through a cassette (LC-to-MPO or SC-to-MPO depends on what the equipment connector is), a straight-through MPO/MTP key up to key down backbone cable and a “cross-over” patch cord (A-to-A) at the other end.

 

method-a

 

Method B is the “cross-over” occurred in the cassette. The keys on the MPO cable connectors are in an up position at both ends, but the fiber that is at connector P1 in one end is in P12 at the opposite end, and the fiber that is in P12 at the originating end is in P1 at the opposing end. Only A-to-B type patch cord is needed for this method.

 

method-b

 

Method C is the most complicated. There is pair-wise “cross-over” in the backbone cable. A-to-B patch cords are used on both ends. The cassette uses MPO/MTP key up to key down and the backbone cable is pair-wise flipped so P1, P2 connects to P2, P1 and P3, P4 connects to P4, P3, etc.

 

method-c

 

Conclusion

Knowing the polarity of MPO/MTP system helps you better upgrade the 40G and 100G networks. According to different polarity methods, choosing the right MPO/MTP patch cables , connectors and cassettes will provide greater flexibility and reliability for your high density network.

Development of SFP Transceiver for DWDM Applications

Dense wavelength division multiplexing (DWDM)transmission systems, which have conventionally been adopted in long-haul backbone networks, are now being adopted in metropolitan area networks along with the recent rapid spread of multimedia services as typified by the Internet. In the applications for metropolitan area networks, the small form-factor pluggable (SFP) and other types of small optical transceivers are generally mounted in high density. Therefore, the development of DWDM optical transceivers in SFP package had been awaited.

Utilizing the accumulated technologies in SFP designing and wavelength control, the authors have successfully developed a 2.5Gbps optical transceiver for DWDM applications in the SFP platform (DWDM-SFP)by developing a compact coaxial transmitter optical subassembly (TOSA) with an integrated Peltier device.

 

Development of compact coaxial TOSA with integrated Peltier device

 

The external view of the newly developed coaxial TOSA with an integrated Peltier device and its pin assignments are shown in Fig. 1 and Fig. 2, respectively. A DFB laser diode (LD), a monitor photo diode (PD), a newly developed Peltier device for controlling the LD temperature and a thermistor for detecting the LD temperature are built into an 8-pin package. An isolator and a fiber receptacle are attached on it. By downsizing these internal parts and minimizing the heat load to reduce the power consumption, the authors realized a cooled coaxial TOSA that is 5.6 mm in diameter and 12.7 mm long, which is one-eighth the size of conventional cooled butterfly-type modules.

 

Figure 3 shows the case temperature dependence of he module’s power consumption. In this evaluation, he temperature and the current of the LD are set to 40 deg. C and 35 mA, respectively. As a result, the power consumption is successfully suppressed to 230 mW or lower, which is eight times smaller than the conventional butterfly-type module. This makes it easy to realize a DWDM-SFP having low power consumption and simple heat radiation structure.

 

Development of package

 

SFP is a pluggable optical transceiver of the size of little finger that is inserted into the open port of communication equipment as shown in Fig. 4. The outline dimensions and other important dimensional specifications of the SFP, such as the receptacle part that the optical connector is inserted into and the edge connector mating with the electrical connector of communication equipment, are standardized by a multi source agreement (MSA). The objective of the development was to create a package that meets not only MSA but also the following structure requirements at a low cost;1) the high-density packaging structure, 2) the efficient heat-radiating structure, and 3) the electromagnetic interference (EMI) shield structure. The solutions for satisfying these requirements are described below.

 

To realize the high-density packaging structure, the authors optimized the three-dimensional arrangement of the internal structure including the outline of the printed circuit board (PCB) and the electronic components on it.The maximum operating case temperatures of DWDM-SFP and TOSA are 70 and 75 deg. C, respectively. Therefore, it is necessary to keep the temperature difference between SFP and TOSA within 5 deg. C. The part number 1 and number 2 in Fig. 5 which take on the function of radiating heat, are made of copper alloy and their thermal conductivities are 350 and 300 W/mK, respectively. The part number 1 has the function of transporting heat from the transceiver IC and other components mounted on the PCB to the rear of the SFP. The heat from TOSA and receiver optical sub-assembly (ROSA) is transported by the thermal sheets at the upper and bottom sides of the package. Figure 6 is a conceptual diagram showing these three heat conducting paths, and Fig. 7 shows the result of the thermal simulation. In Fig. 7, the temperature of the area“a” is low enough compared to that of the other areas, which indicates that TOSA is well separated thermally from other heat sources. Figure 8 is the measurement result of the case temperature difference between TOSA and SFP. It shows that the temperature difference is below 5 deg. C at any condition.3-3 EMI shield structure The typical method for creating an EMI shield structure is to give metal plating to the receptacle part. Because metal plating is costly, the authors developed a new structure for EMI shielding by three-dimensionally assembling the internal sheet metal parts instead of conducting the plating process to the receptacle part. Figure 9 shows the result of the EMI measurement of 16 pieces of DWDM-SFP. The Federal Communications Commission (FCC) specifies that the electromagnetic radiation is to be strictly limited to below 54 dBuV/m.

There are also have some development in circuit board and Wavelength control technique, here we just not describe in details.

 

Conclusion

 

The authors have successfully developed a SFP-sized 2.5Gbps optical transceiver for DWDM applications. Miniaturization and low power consumption (1 W) are achieved by developing the following approaches; a compact coaxial TOSA with an integrated Peltier device, an optimized heat-radiation structure, and a high-density mounting board with the newly developed transceiver IC. In addition, the optimized TOSA design and precise wavelength control by CPU have allowed the transceiver to have a good wavelength stability, which sufficiently meets the 100 GHz grid spacing with only the temperature control of direct modulated LD. Moreover, an excellent characteristic was achieved in long-haul transmission. The authors are planning to develop the DWDM-SFP having higher added values, such as further low power consumption and RoHS compliance, in future. If you want to know more professional knowledge about the SFP or DWDM/CWDM/OADM, please contact fiber-mart.com. Here we will provide products such as CWDM/DWDM/modules, andCWDM OADM and DWDM OADM modules (such asDWDM 1 channel OADM).

Introduction of Optical Attenuator

An optical attenuator is a device used to reduce the power level of an optical signal, either in free space or in an optical fiber. Fiber optic attenuator is an optical attenuator used in the fiber optic communications to reduce the optical fiber power at a certain level. The most commonly used type is female to male plug type fiber optic attenuator. It has the fiber connector at one side and the other side is a female type fiber optic adapter, with fiber optic attenuator name based on the connector type and the attenuation level.

Types of Optical Attenuator

Optical attenuators are typically classified as fixed or variable optical attenuator.

Fixed optical attenuators
Fixed optical attenuators used in fiber optic systems may use a variety of principles for their functioning. Preferred attenuators use either doped fibers, or mis-aligned splices, since both of these are reliable and inexpensive. Inline style attenuators are incorporated into patch cables. The alternative build out style attenuator is a small male-female adapter that can be added on to other cables.

Variable optical attenuators
Variable optical attenuators generally use a variable neutral density filter. Despite relatively high cost, this arrangement has the advantages of being stable, wavelength insensitive, mode insensitive, and offering a large dynamic range. Other schemes such as LCD, variable air gap etc. have been tried over the years, but with limited success. For precise testing purposes, engineers have also designed instrument type variable optical attenuators. They have high attenuation ranges, such as from 0.5 dB to 70dB. They also have very fine resolution, such as 0.01dB. This is critical for accurate testing.

Variable optical attenuator instrument calibration is a major issue. The user typically would like an absolute port to port calibration. Also, calibration should usually be at a number of wavelengths and power levels, since the device is not always linear. However a number of instruments do not in fact offer these basic features, presumably in an attempt to reduce cost. The most accurate variable attenuator instruments have thousands of calibration points, resulting in excellent overall accuracy in use.

Applications of Optical Attenuator

Fiber optic attenuator is used in applications where the optical signal is too strong and needs to be reduced. Optical attenuators are commonly used in fiber optic communications, either to test power level margins by temporarily adding a calibrated amount of signal loss, or installed permanently to properly match transmitter and receiver levels.

For example, in a multi-wavelength fiber optic system, you need to equalize the optical channel strength so that all the channels have similar power levels. This means to reduce stronger channels’ powers to match lower power channels. Another example is when the received optical power is so strong that it saturates the receiver, you need an optical attenuator to reduce the power so the receiver can detect the signal correctly.

Fiber optic attenuators are usually used in two scenarios. The first case is in fiber optic power level testing. Optical attenuators are used to temporarily add a calibrated amount of signal loss in order to test the power level margins in a fiber optic communication system. In the second case, optical attenuators are permanently installed in a fiber optic communication link to properly match transmitter and receiver optical signal levels.

How to Measure the Fiber Optic Network by Using OTDR Testers?

Optical fiber measurement can be divided into three steps: using OTDR testers for parameter setting, data acquisition and analysis. Measuring parameters include artificial Settings.

(1) the wavelength selection (λ):

Because of different wavelengths corresponding to different features (including attenuation, slightly curved, etc.), generally following the test wavelength and wavelength corresponds to the principle of transmission communication system, the system open 1550 wavelengths, the test wavelength of 1550nm.

 

(2) Pulse Width:

The longer the pulse width, the bigger the dynamic measurement range, measurement of distance is longer, but blind area is bigger in OTDR curve waveform; Short pulse injection of low light level, but can reduce the blind area. Usually stand by ns for pulse width cycle.

 

(3) Range:

OTDR testers measurement range is refers to the maximum distance of OTDR data sampling, the choice of this parameter determines the size of the sampling resolution. Best measurement range for 1.5 ~ 2 times the distance between optic fiber network length.

 

(4) Average time:

The backward scattering light signal is very weak, generally USES the statistical average method to improve the signal-to-noise ratio, average, the longer the average time, the higher signal-to-noise ratio.

 

(5) Parameters of optical fiber

Optical fiber parameter setting including the refractive index n and Backscatter coefficient of η. Refractive index parameters related to distance measuring, backscatter coefficient effects the measurement results of reflection and return loss.

After Parameter Settings, OTDR can be sent and received by the optical fiber link light pulse scattering and reflected light, the photodetector outputs sample, get the OTDR curve, the curve is analyzed to understand quality of optical fiber.

 

Experience and skills

(1) Simple discriminant of fiber quality

Under normal circumstances, OTDR test the light curve of the subject (single or several plate cable) slope are consistent, if a certain section of the slope is bigger, indicates the period of decay; If subject to irregular shape curve, the slope is volatile, it is bent or arc, suggests that bulk fiber cables quality degradation seriously, do not conform to the requirements of the communication.

 

(2) The choice of wavelength and the test of Uni and Bi-direction:

1550 wavelengths to test distance is farther, a 1550nm – 1550nm fiber is more sensitive to bending than 1310. In an actual optical cable maintenance, compare both wavelengths to get good test results.

(3) Clean the joint:

Before accessing optical union, must be cleaned carefully, including OTDR output fiber assembly connectors and measured union, or the insertion loss will too big, otherwise don’t reliable, much noise can stop the measurement, it may also damage the OTDR. Avoid using alcohol cleaning or other refractive index matching liquid, because they can dissolve the adhesive within optical fiber connector.

 

(4) The use of additional optical fiber

Additional optical fiber is used to connect OTDR and optical fiber which under test, 300 ~ 2000 m long fiber, its main role is: the front insert measuring blind area processing and terminal connector.

 

In general, OTDR and optical fiber connectors between blind area under test is the largest. In actual measurement of the optical fiber in the OTDR with fiber and after a period of transition, the front end blind area falls within the transition of optical fiber, the fiber under test head fell on the OTDR curve in the linear region. Optical fiber system between connector insertion loss by OTDR testers and optical fiber to measure for a period of transition. As to measure the first and end connector on both ends of the insertion loss, can add a transitional fiber in every side.

Maintaining Fiber Network With Fiber Optic Identifier

During fiber optic network installation, maintenance or restoration, it is also often necessary to identify a specific fiber without disrupting live service. This battery powered instrument looks like a long handheld bar is called fiber optic identifier or live fiber identifier.

 

Optical fiber identifier employs safe and reliable macro bending technology to avoid disruption of network communications that would normally be caused by disconnecting or cutting a fiber optic cable for identification and testing. The fiber optic identifier is intended for engineers and technicians to identify dark or live fiber and excessive losses due to the misalignment of mechanical splices or poor connections.

 

There is a slot on the top of fiber identifier. The fiber under test is inserted into the slot, then the fiber identifier performs a macro-bend on the fiber. The macro-bend makes some light leak out from the fiber and the optical sensor detects it. The detector can detect both the presence of light and the direction of light.

 

A fiber optic identifier can detect “no signal”, “tone” or “traffic” and it also indicates the traffic direction. The optical signal loss induced by this technique is so small, usually at 1dB level, that it doesn’t cause any trouble on the live traffic. Fiber optic identifiers can detect 250um bare fibers, 900um tight buffered fibers, 2.0mm fiber cables, 3.0mm fiber cables, bare fiber ribbons and jacketed fiber ribbons.

 

Most fiber identifiers need to change a head adapter in order to support all these kinds of fibers and cables. While some other models are cleverly designed and they don’t need to change the head adapter at all. Some models only support single mode fibers and others can support both single mode and multimode fibers.

 

Difference Between Fiber Identifier and Visual Fault Locator

Fiber optical identifier and fiber optic visual fault locator all are most important tools for testing in our network. But sometimes we would mistake them. To be honest, they are different test tools.

 

1. Fiber Optical Identifier, it is a very sensitive photodetectors. When you will be a fiber bending, some light rays from the fiber core. The light will be detected by the fiber identification, technical staff according to these light can be a single fiber in the multi-core optical fiber or patch panel identified from the other fiber out. Optical Fiber Identifier can detect the status and direction of the light does not affect the transmission. In order to make this work easier, usually at the sending end to the test signal modulated into 270Hz, 1000Hz or 2000Hz and being injected into a specific fiber. Most of the optical fiber identifier for the operating wavelength of 1310nm or 1550nm single-mode fiber optical fiber, optical fiber identifier can use the macro folding technology to name the direction and power of the transmission fiber and the fiber under test online.

 

fiber optic identifier from Sunmafiber

 

2. VFL (Visual Fault Locator)

This revolutionary product is based on laser diode visible light (red light) source, when the light being injected into the fiber, if fiber fracture, connector failure, folding over, poor weld quality failure by launching the light of the fiber to fiber fault visual images positioning. Visual Fault Locator launched a continuing trend (CW) or pulsed mode. The common frequency of 1Hz or 2Hz, but can also work in the kHz range. Usually the output power of 0dBm (1mW) or less, the working distance of 2 to 5km, and to support all the common connector.

 

You can get fiber optic identifiers from Wilcom, Ideal, 3M, Sunmafiber and other network test equipment manufacturer. We recommend you Wilcom and Sunmafiber products since both manufacturers have very high customer satisfaction rate.

Fiber Splitter for FTTH Applications

Passive optical network (PON) has been widely applied in the construction of FTTH (fiber to the home). With PON architecture, network service providers can send the signal to multiple users through a single optical fiber, which can help them save great costs. To build the PON architecture, optical fiber splitter is necessary.

 

What Is Fiber Splitter?

The fiber splitter is a passive component specially designed for PON networks. Fiber splitter is generally a two-way passive equipment with one or two input ports and several output ports (from 2 to 64). Fiber splitter is used to split the optical signal into several outputs by a certain ratio. If the ratio of a splitter is 1×8 , then the signal will be divided into 8 fiber optic lights by equal ratio and each beam is 1/8 of the original source. The splitter can be designed for a specific wavelength, or works with wavelengths (from 1260 nm to 1620 nm) commonly used in optical transmission. Since fiber splitter is a passive device, it can provide high reliability for FTTH network. Based on the production principle, fiber splitters include Planar Lightwave Circuit (PLC) and Fused Bionic Taper (FBT).

 

PLC Splitters

PLC splitters are produced by planar technology. PLC splitters use silica optical waveguide technology to distribute optical signals from central office to multiple premise locations. The output ports of PLC splitters can be at most 64. This type of splitters is mainly used for network with more users.

 

The Structure of PLC splitters

Internal Structure

 

The following figure shows a PLC splitter. The optical fiber is splitted into 32 outputs. PLC chip is made of silica glass embedded with optical waveguide. The waveguide has three branches of optical channels. When the light guided through the channels, it is equally divided into multiple lights (up to 64) and transmitted via output ports.

 

1x32-plc-splitter

 

Outside Configuration

 

Bare splitter is the basic component of PLC fiber splitter. For better protection of the fragile fiber and optimized use, PLC splitters are often equipped with loose tube, connector and covering box. PLC splitters are made in several different configurations, including ABS, LGX box, Mini Plug-in type, Tray type, 1U Rack mount, etc. For example, 1RU rack mount PLC splitter (as shown in the figure below) is designed for high density fiber optical distribution networks. It can provide super optical performance and fast installation. This splitter is preassembled and fibers are terminated with SC connectors. It’s ready for immediate installation.

 

rack-mount-plc-spllitter

 

FBT Splitters

FBT splitters are made by connecting the optical fibers at high temperature and pressure. When the fiber coats are melted and connected, fiber cores get close to each other. Then two or more optical fibers are bound together and put on a fused taper fiber device. Fibers are drawn out according to the output ratio from one single fiber as the input. FBT splitters are mostly used for passive networks where the split configuration is smaller.

 

PLC Splitters From fiber-mart.COM

Fiberstore offers a wide range of PLC splitters that can be configured with 1xN and 2xN. Our splitters are designed for different applications, configurations including LGX, ABS box with pigtail, bare, blockless, rack mount package and so on.

A Quick Guide To Fiber Optic Power Meter

When you install and terminate fiber optic cables, you always have to test them. A test should be conducted for each fiber optic cable plant for three main areas: continuity, loss, and power. And optical power meters are part of the toolbox essentials to do this. There are general-purpose power meters, semi-automated ones, as well as power meters optimized for certain types of networks, such as FTTx or LAN/WAN architectures. It’s all a matter of choosing the right gear for the need.

Here is a quick guide to fiber optic power meters and how they work.

 

Optical power meters are commonly used to measure absolute light power in dBm. For dBm measurement of light transmission power, proper calibration is essential. A fiber optic power meter is also used with an optical light source for measuring loss or relative power level in dB. To calculate the power loss, optic power meter is first connected directly to an optical transmission device through a fiber optic pigtail, and the signal power is measured. Then the measurements are taken at the remote end of the fiber cable.

 

Fiber optic power meter detects the average power of a continuous beam of light in an optical fiber network, tests the signal power of laser or light emitting diode (LED) sources. Light dispersion can occur at many points in a network due to faults or misalignments; the power meter analyzes the high-powered beams of long-distance single-mode fibers and the low-power multibeams of short-distance multimode fibers.

 

Important specifications for fiber optic power meters include wavelength range, optical power range, power resolution, and power accuracy. Some devices are rack-mounted or hand held. Others are designed for use atop a bench or desktop. Power meters that interface to computers are also available.

 

The fiber optic power meter is a special light meter that measures how much light is coming out of the end of the fiber optic cable. The power meter needs to be able to measure the light at the proper wavelength and over the appropriate power range. Most power meters used in datacom networks are designed to work at 850nm and 1300nn. Power levels are modest, in the range of –15 to –35dBm for multimode links, 0 to –40dBm for single mode links. Power meters generally can be adapted to a variety of connector styles such as SC, ST, FC, SMA, LC, MU, etc.

 

Generally, multimode fiber is tested with LEDs at both 850nm and 1300nm and single mode fiber is tested with lasers at 1310nm and 1550nm. The test source will typically be a LED for multimode fiber unless the fiber is being used for Gigabit Ethernet or other high-speed networks that use laser sources. LEDs can be used to test single mode fibers less than 5000 meters long, while a laser should be used for long single mode fibers.

 

Most fiber optic power meters are calibrated in linear units such as milliwatts or microwatts. They may also provide measurements in decibels referenced to one milliwatt or microwatt of optical power. Typically, fiber optic power meters include a removable adaptor for connections to other devices. By measuring average time instead of peak power, power meters remain sensitive to the duty cycle of digital pulse input streams.

 

Use fiber optic power meter and other useful fiber optic tool kits to ensure that your fiber optic system will operate smoothly.

the right way to Use Field Assembly Connector

The expansion of FTTH application has brought prosperity to the manufacturing of field assembly connectors for fast field termination. This type of connector gains its popularity due to the applicability to cable wiring and compact bodies which are easily stored in optical fiber housings. With excellent features of stability and low loss, field assembly connector has now become a reliable and durable solution for fiber optic systems. However, do you really know the field assembly process of the connector? This article provides an easy guide to show you the way of using field assembly connector.

 

Introduction to Field Assembly Connector

 

Before getting to know the instruction process, let’s have a look at the basic knowledge about field assembly connector. Field assembly connector or fast connector is an innovative field installable optical fiber connector designed for simple and fast field termination of single fibers. Without using additional assembling tools, field assembly connector can be quickly and easily connected to the drop cable and indoor cable, which saves a lot of required termination time. It is specially designed with the patented mechanical splice body that includes a factory-mounted fiber stub and a pre-polished ceramic ferrule. Field assembly connector is usually available for 250 µm, 900 µm, 2.0 mm and 3.0 mm diameter single-mode and multimode fiber types. The whole installation process only takes about 2 minutes which greatly improves the working efficiency.

 

field-assembly-connector

 

Internal Structure of Field Assembly Connector

 

From the following figure, we can see the specific internal structure of field assembly connector. The ferrule end face of the connector is pre-polished in a factory for later connection with the fiber. A mechanical splice is also formed at the end of the ferrule for mechanical fixation of optical fiber. The mechanical splice consists two plates, one with a V groove, another with flat surface above the V groove, and a clamp for the insertion of the two plates. When inserting the fiber, a wedge clip will keep the V groove open for easier installation. After the fiber insertion, the wedge clip can be extracted from the V groove.

structure-of-field-assembly-connector

 

Features and Applications

 

Key Features

Field-installable, cost-effective, user-friendly

No requirement for epoxy and polishing

Quick and easy fiber termination in the field

No need for fusion splicer, power source and tool for pressure

Visual indication of proper termination

 

Applications

 

Fiber optic telecommunication

Fiber distribution frame

FTTH outlets

Optical cable interconnection

Cable television

 

Field Assembly Instruction Guide

 

Although it is an simple way to use field assembly connector, the right operation process is also important. Here will introduce some basic steps for connector installation.

 

Step 1, prepare the field assembly connector parts and related tools required during the process. There is no need for special tools, but fiber cleaver and jacket stripper are still necessary.

Step 2, insert the connector boot into the fiber cable.

Step 3, cut and reserve 10mm bare fiber by fiber cleaver and then make sure the total fiber length of 30 mm.

Step 4, insert the fiber from bottom until the stopper and make fiber present micro bend.

Step 5, press the press cover to tight the bare fiber.

Step 6, lock the boot with yarn.

Step 7, cut the yarn.

Step 8, screw the boot and put on housing to complete assembly.

 

field-assembly-guide

 

Precautions

 

Here are some precautions for you to notice during the process:

Point 1, the product is sensitive to dirt and dust. Keeping it away from any possible contamination is necessary.

Point 2, the performance will be influenced by the fiber cutting surface condition. Use a cutter with a sharp blade for the best results.

Point 3, insert the fiber into the connector slowly. If the fiber is roughly inserted, it might be damaged or broken, leading to failure of connector installation. Broken fiber could scatter in all directions.

Point 4, do not remove the dust cap until the connector has been completely assembled in order not to cause a high insertion loss.

Point 5, a proper amount of index matching gel is applied in the connector. Do not insert fiber more than once into connector.

Fiber-MART.COM Solutions for Field Assembly Connectors

 

#ID Description

35165 LC/PC Singlemode Pre-polished Ferrule Field Assembly Connector Fast/Quick Connector

35166 LC/PC Multimode Pre-polished Ferrule Field Assembly Connector Fast/Quick Connector

34829 LC/PC Singlemode Straight-through Field Assembly Connector Fast/Quick Connector

38720 LC/APC Singlemode Pre-polished Ferrule Field Assembly Connector Fast/Quick Connector

13225 SC/APC Type A Singlemode Pre-polished Ferrule Field Assembly Connector Fast/Quick Connector

39958 SC/UPC Singlemode Pre-polished Ferrule elite Field Assembly Connector Fast/Quick Connector

13226 FC/PC Singlemode Pre-polished Ferrule Field Assembly Connector Fast/Quick Connector

 

Conclusion

 

Fiber assembly connector enables quick termination to improve reliable and high connector performance in FTTH wiring and LAN cabling systems. All the above solutions provided by fiber-mart.com are available to meet your requirements. Please visit the website for more information.

how about the Optical Amplifier Market

Optical Amplifiers are evolving. There are various types including the EDFA, Raman, and Semiconductor configurations. The EDFA optical amplifier units can be used in telecom and datacom (SONET/SDH/DWDM/Gigabit Ethernet) applications to change an electrical signal into an optical signal and vice versa.

 

According to Susan Eustis, lead author of the study, "Optical Amplifiers are used to update the communications networks to manage broadband, to update the data center networks to make them manage traffic with higher speeds, to implement the backbone network for mobile communications.

 

"Everything is going mobile. This evolution is driven by mobile smart phones and tablets that provide universal connectivity. With 6 billion cell phones in use and one billion smart phones, soon to be 6 billion smart phones, a lot of people have access to mobile communication. Video, cloud-based services, the internet, and machine-to-machine (M2M) provide mobile connectivity. All these devices are networked and drive significant traffic to the broadband network, stimulating the need for optical transceivers."

 

The optical amplifier component market is intensely competitive. There is increasing demand for optical components as communications markets grow in response to more use of smart phones and more Internet transmission of data. The market for network infrastructure equipment and for communications semiconductors offers attractive long-term growth: Data center growth is in response in part to the growth of bid data, and in part to the incredible bandwidth being consumed by video content. New programming is moving to broadcast quality short videos that can be downloaded by users Users can download broadcast quality news or training videos as broadband networks become universally available.

 

Low bandwidth video does not directly drive adoption of optical components. It indirectly does by creating demand for broadband data transport. Video capability at the high end of the market is creating need for network high speed of transmission just because of the quantity of data being transmitted.

 

The Optical Transport Network (OTN) is a set of optical network elements connected by optical fiber links. Optical network elements provide transport, multiplexing, switching, management, supervision and survivability of communication channels. Carrier Ethernet is emerging. Optical transceiver, transmitter, receiver, and transponders support the implementation of the new network capacity.

 

Optical amplifier components are an innovation engine for the network supporting end to end data transport over optical systems. Optical components support and enable low-cost transport throughout the network. Optical components are needed for high speed network infrastructure build-outs. These are both for carriers and data centers. Network infrastructure build-out depends on the availability of consultants who are knowledgeable.

 

Optical amplifiers are evolving to be compliant with the 10Gbps Small Form Factor Pluggable (XFP) Multi-Source Agreement (MSA) specification for next generation optical transceiver devices. There is expected to be tremendous investment in wireless cell tower base stations as the quantity of network traffic grows exponentially. Carriers worldwide are responding to the challenges brought by the massive increase in wireless data traffic. The advent of big data and exponential growth of data managed by the enterprise data centers is a significant market factor.

 

The global optical amplifier market at $900 million in 2012 is anticipated to reach $2.8 billion by 2019. Growth is driven by the availability of high speed processors and component devices that support increased speed and traffic on the optical networks. The migration to all optical networks is ongoing.

 

Markets are driven by the availability of 100 Gbps devices and the vast increases in Internet traffic. Internet traffic growth comes from a variety of sources, not the least of which 1.6 billion new smart phones sold per year. Smartphone market growth is causing the need for investment in backhaul and cell tower technology.

 

Worldwide optical transport market revenues are forecast to grow rapidly through 2019. This is in the context of a world communications infrastructure that is changing. Technology is enabling interaction, innovation, and sharing of knowledge in new ways.