How to Choose Optical Distribution Frame

Due to the development of high speed transmission, demands for high density patching have increased in recent years. However, the management of installed cables still remains a difficult task. To achieve a simpler way of cable organization, people often use the cost-effective optical distribution frames (ODF) to arrange optical cable connections. ODF plays an important part in building a safe and flexible operation environment for optical network. Different kinds of ODFs are provided in the market, but you need to choose the right one according to actual situation.

Functions of ODF

ODF is mainly used for fiber optic terminal splicing, fiber optic connector installation, optical path adjusting, excess pigtail storage and fiber optic cable protection. When cable enters into the rack, ODF should mechanically fix the cable and install the ground wire protection. Fiber optic cables will also be divided into groups for better management. When it comes to the spliced fibers, extra parts will be stored as a coil and the fusion splices are well-protected in the ODF. Adapters and connectors are pluggable and optical path can be freely adjusted or tested. Moreover, enough space of ODF is provided to satisfy a clear connection.

Things to Consider for Choosing ODF

Selecting a right ODF is vital to future applications. Here are some recommended aspects for you to consider before purchasing:

1) ODF Types

Generally, there are three types in terms of its structure. They are wall mount ODF, floor mount ODF and rack mount ODF. Wall mount ODF shapes are like a small box installed on the wall. Because the space is restrained, wall mount ODF only accepts small fiber counts. Floor mount ODF has a fixed and large fiber capacity in a closed structure. Rack mount ODF is more flexible to be installed on the rack to meet your requirements for different cable counts and specifications. This type is frequently used in optical distribution system with 19 inches’ specification to accommodate the size of standard transmission rack.

2) Fiber Counts

High density fiber counts have become the trend for future data center. Today, a single ODF unit usually has 12, 24, 36, 48, 72, 96 or even 144 ports. Customized ODF according to your needs is also available in the market.

3) Easy Management

Using a high density device will definitely increase the difficulty of cable management. ODF should allow for easy access to the connectors on the front and rear ports for quick insertion and removal, which means that ODF must provide adequate space. Besides, ODF should have the right colored adapters to match with optical connectors in case of wrong connections.

4) Good Protection

One basic function of ODF is the protection function. A standard ODF should comprise protection devices to prevent fiber optic connections from dust or stress damages. For instance, the splicing connection is very sensitive to outside environment and is important to the normal operation of a network, so the good quality of ODF protection device is of great importance.

Conclusion

In a word, ODF is now an indispensable equipment for the deployment of optical network. High-density ODF is especially popular in the industry. To find a suitable ODF with a lower price, careful selection is important. This article only provides some basic factors that may affect the application of ODF. For more information, please visit FS.COM.

Source:http://www.fiber-optical-networking.com/choose-optical-distribution-frame.html

MTP/MPO - An Easier Solution for High Density Patching

With the continuing growth of data throughput in networking, 40G network now becomes the commonplace and 100G has also been used increasing widespread. To achieve a higher transmission data rate, it is important to find a suitable solution for the high density cable routing. Thus, the arrival of MTP/MPO connection standard is a piece of good news for high density patching. The MTP/MPO technology is available with multi-fiber connectors which is a perfect solution for high-performance data transmission. There are a lot of benefits when adopting the MTP/MPO structure. This article will provide some effective MTP/MPO assemblies that are frequently used to meet high density demands.

Superiority of MPO/MTP Assemblies

Actual practice proves that MPO/MTP components are superior to other assemblies in high density applications. They can connect to equipment with various date rates of 10 Gbps, 40 Gbps or 100 Gbps, which makes them more flexible for the devices. Also, their installation is very simple. No tools are required to install the cassette in the panel enclosure, and the push-pull connection offers an easier way to be locked or unlocked in patch panels. Owing to the modular cassette system, they are also pretty adjustable in network reconfiguration. You may think this must cost you a great deal, however, the initial investment is very cost-effective.

Recommended MPO/MTP Products

Here are some recommended MPO/MTP products for high density patching. Using these assemblies can achieve a significant progress in operations.

1) MTP/MPO Cables

MTP/MPO cables consist of MTP/MPO connectors and fiber cables. Sometimes, other types of connector can also be linked to one termination. The fiber cables are usually employing OM3 or OM4 laser optimized multimode optical fibers. MTP/MPO trunk cables, harness/breakout cables and direct pigtails are three categories of MTP/MPO cables. The MTP/MPO trunk cables are available with 8, 12, 24, 36, 48, 72 and 144 fibers for single-mode and multimode applications. The harness/breakout cables is designed to work from trunk backbone assemblies to fiber rack system in the high density cabling. One end is terminated with a MTP/MPO connector, and the other end can have other options of connectors such as LC/SC/ST/MTRJ. The MTP/MPO pigtail cables are typically used for splicing directly inside fiber management panels near adapter ends.

2) MTP/MPO Cassettes

Appropriate utilization of MTP/MPO cassettes can help reduce installation time and investment for an optical network infrastructure in the premises. Rapid deployment of high density data center infrastructure can also be realized thanks to the modular system. The MTP/MPO plug-n-play cassette provides the interconnection between MTP/MPO backbones with LC/SC/ST/FC patching. Other recommended cassettes are 1U 19” rack mount cassettes holders, 4U 19” rack mount cassettes holders and 144 ports ultra HD angled patch panel. 1U 19” rack mount enclosure is integrated with three pieces of plug-n-play cassettes for up to 72 fibers patching. 4U 19” rack mount enclosure has 12 plug-n-play cassette pieces with 288 fibers patching. 144 ports ultra high density cassette is equipped with 72 LC duplex adapters for 144 fibers patching.

3) MTP/MPO Optical Adapter & Adapter Panels

The black colored MTP/MPO adapter has two types as key-up to key-down and key-up to key-up. It provides the connection between cable to cable or cable to equipment in the MTP/MPO style. The MTP/MPO fiber adapter panels are available with 2, 3, 4, 6, 8, 12, 16 and 18 ports both horizontally and vertically in lighter package.

Conclusion

In summary, if you need devices for high density deployment, MTP/MPO assemblies are absolutely best solutions. Applying the MTP/MPO connection, its patch cables, cassettes and adapters will be promoted to a more effective use.

Source:http://www.fiber-optic-cable-sale.com/mtpmpo-an-easier-solution-for-high-density-patching.html

Effective CWDM & DWDM Mux/Demux Solutions for WDM System

Wavelength division multiplexing (WDM) system is designed for high capacity communications. It is now frequently used as a method to merge multiple optical signals with different wavelengths onto a single fiber. There are two divisions of WDM system: coarse wavelength division multiplexing (CWDM) and dense wavelength division multiplexing (DWDM). Using WDM can enhance the effectiveness of bandwidth in fiber optic communications. The WDM Mux/Demux has a number of communication channels, and matches with a certain frequency. Wavelengths are separated to different receivers at the destination. Mux/Demux module is an important assembly using WDM technology. This article will introduce some effective CWDM and DWDM Mux/Demux solutions for WDM system.

CWDM Mux/Demux & DWDM Mux/Demux

CWDM Mux/Demux

CWDM Mux/Demux is a flexible network solution for WDM optical networks. At most 18 full-duplex wavelengths can be added over a single fiber trunk which greatly alleviates fiber exhaustion. With low insertion loss and high stability, CWDM Mux/Demux is applied to many operations, such as CATV links, WDM systems, test and measurement, metro and access networks, FTTH networks, etc. The deployment of CWDM Mux/Demux is transparent and clear. Its compact form factor enables a much easier manipulation. Only coarse wavelengths can be transmitted over the fiber which reduces the WDM system cost.

Three kinds of CWDM Mux/Demux are widely used in the application. They are 1RU 19" rack chassis CWDM Mux/Demux, half 19"/1RU CWDM Mux/Demux and splice/pigtailed CWDM Mux/Demux. CWDM Mux/Demux in 19 inch rack mount package is often used for CWDM, EPON and CATV network. Half 19"/1RU CWDM Mux/Demux is packed in LGX box using thing film coating and non-flux metal bonding micro optics packaging. Splice/pigtailed CWDM Mux/Demux is packed in the ABS box package based on standard thin film filter (TFF) technology.

DWDM Mux/Demux

DWDM Mux/Demux conveys optical signals in a more dense wavelength. It is especially used for long distance transmission where wavelengths are highly-packed together. The maximum delivered wavelengths can reach up to 48 channels in 100GHz grid (0.8nm) and 96 channels in 50GHz grid (0.4nm). DWDM Mux/Demux uses a reliable passive WDM technology that achieves low insertion loss. And it provides a solution for adding WDM technology to any existing network device. Applications like point-to-point DWDM fiber optimization, linear add/drop DWDM fiber optimization, external optical monitoring are typically using DWDM Mux/Demux module.

Likewise, 1RU 19" rack chassis DWDM Mux/Demux, Half 19"/1RU DWDM Mux/Demux and splice/pigtailed DWDM Mux/Demux are three divisions of DWDM Mux/Demux modules. The first type is in 19 inch rack mount package used for long-haul transmission over C-band range of wavelengths. The second one is in LGX package used for PDH, SDH/SONET, Ethernet services transmission. The last one is in ABS box package and its pigtails are labeled with wavelengths.

Effective CWDM Mux/Demux & DWDM Mux/Demux Solutions

18-CH CWDM Mux/Demux

18-CH CWDM Mux/Demux is a highly recommended 1RU rack-mount CWDM Mux/Demux that combines 18 CWDM sources on a single fiber. The insertion loss is below 4.9 dB. Moreover, it has a monitor port that enables maintenance without ceasing the operation.

40-CH DWDM Mux/Demux

40-CH DWDM Mux/Demux has 40 channels. As a DWDM Mux/Demux module with high density, low-loss and independent 1RU rack mount package, the best utilization of this device is to employ it for high density applications over long-haul transmission. It multiplexes and demultiplexes 40 DWDM wavelengths with 100 GHz in a ring or point-point network. It is a highly cost-effective DWDM Mux/Demux module.

Conclusion

To improve the efficiency of network transmission, WDM technology is often deployed in the devices. 18-CH CWDM Mux/Demux and 40-CH DWDM Mux/Demux are now recommended as the most cost-effective WDM solutions with expanded fiber capabilities. Hope you can choose and use them wisely.

Source:http://www.chinacablesbuy.com/effective-cwdm-dwdm-muxdemux-solutions-for-wdm-system.html

OADM - Optical Add-Drop Multiplexer

With the development of optical communication technologies, people are entering into the new era of information. In order to overcome the data rate limitation of traditional communication system, WDM and OTDM technologies are typically used to increase fiber optic bandwidth. However, no matter which kind of technology is adopted to construct fiber optic network, optical add-drop multiplexer (OADM) technology is needed in the system. It makes the fiber optic network more flexible, optional and transparent. OADM is now a key component of the all-optical network to enhance the network reliability and efficiency. This article will give a brief introduction about the basic knowledge of OADM.

Definition of OADM

So what is an optical add-drop multiplexer or OADM? To be specific, an OADM is a device used in wavelength-division multiplexing systems for multiplexing and routing different channels of light into or out of a single-mode fiber. “Add” refers to the capability of the device to add one or more new wavelength channels to an existing multi-wavelength WDM signal. On the contrary, “drop” refers to its ability of removing one or more channels and passing those signals to another network path.

There are three parts of a traditional OADM - an optical demultiplexer, an optical multiplexer and a reconfiguration method between the demultiplexer and the multiplexer. The demultiplexer separates wavelengths from an input fiber onto different ports. The multiplexer multiplexes the wavelength channels that come from demultiplexer ports with those from the add ports onto a single output fiber. The reconfiguration can be achieved by a fiber patch panel or by optical switches which direct the wavelengths to the multiplexer or to drop ports.

Operating Principle of OADM

The WDM signal contains multiple wavelength channels. When these wavelengths enter into the main input of OADM, they can be selected to enter the drop output ports according to your application requirements. Correspondingly, the add ports will input the required wavelength channels. And those irrelevant wavelengths will directly pass through OADM and then be multiplexed with the added wavelengths together leaving the main output. Therefore, the function of OADM is to download necessary local signals and upload signals for the user of next node.

Two Kinds of OADM

Fixed OADM and reconfigurable OADM are two commonly used types of OADM. The former is used to drop or add data signals on dedicated WDM channels, and the latter is used to electronically alter the selected channel routing through the optical network.

Fixed OADM or FOADM is the traditional construction of OADM. It uses a filter to select a dropping wavelength and a multiplexer to add a new channel at the same wavelength. Different from FOADM, reconfigurable OADM or ROADM is a dynamic type which has the ability to remotely switch traffic from a WDM system at the wavelength layer. It provides flexibility in rerouting optical streams, avoids faculty connections, and allows minimal service disruption and the ability to adapt or upgrade the optical network to different WDM technologies.

Conclusion

OADM is an important element of an optical fiber network. It can be both deployed for long-haul core networks or short metro networks. Fixed OADM and reconfiguration OADM are two commonly used types. A further development of OADM is absolutely the future trend in fiber optic communications.

Source:http://www.fiber-optic-cable-sale.com/oadm-optical-add-drop-multiplexer.html

Guide to Optical Amplifier

Optical amplifier is an significant device deployed for optical communication and laser physics. No need for converting optical signals into electrical signals first, optical amplifier can directly amplify the optical signals. It is considered to be a laser without optical cavity or with suppressed feedback from cavity. Optical amplifiers are often installed at places where optical signals are weak and need to be enhanced. This ensures the stable transmission of optical signals in the rest cables. Thus, we should attach greater importance to optical amplifier. And this article will guide you to know the secrets of optical amplifier.

Functions of Optical Amplifier

In an optical network, optical amplifiers can be used as booster amplifiers, pre-amplifiers or inline amplifiers. These functions are a little different from each other. When a optical amplifier acts as a booster, it is used to amplify the signals that leave the transmitter into the required level before entering into fiber links. The booster amplifier is especially important to a WDM link as the multiplexer attenuates optical signals. Pre-amplifier is used at the other end of a link to amplify the signal level for it to be detected over or above the thermal noise of the receiver. As for inline amplifier, it is used for links over 150 km in case signals become weak in long distance. Every 80 to 100 km, inline amplifier will be placed to make sure that the signal level is over the noise floor.

Three Types of Optical Amplifiers

1) Erbium Doped Fiber Amplifier (EDFA)

Erbium doped fiber amplifier or EDFA is now the most widely used optical amplifier for long range fiber communications. Its optical fiber (usually a single-mode fiber) at the core is doped with rare earth element erbium to absorb light at one frequency and emit light at another frequency. The light is pumped from laser diodes with a wavelength around 980 nm and sometimes around 1480 nm. EDFA has advantages of high gain, wide bandwidth, high output power, high pumping efficiency, low insertion loss and insensitive to polarization state which turns out to be a good solution for DWDM, CATV and SDH applications.

2) Roman Amplifier

Roman amplifier is designed based on the Roman gain which results from the effect of stimulated Roman scattering. When a lower frequency signal photon induces the inelastic scattering of a higher-frequency pump photon in an optical medium in the nonlinear regime, another signal photon is produced with the surplus energy resonantly passed to the vibrational states of the medium. Roman amplifier is often installed in the mid-stream of a signal or in front of the receiver to amplify signal levels. It has the advantages of greater operating wavelength range, constant optical gain and effective noise figure reduction.

3) Semiconductor Optical Amplifier (SOA)

Semiconductor optical amplifier or SOA is the optical amplifier based on a semiconductor gain medium. Light is sent through a semiconductor single-mode waveguide with transverse dimensions. SOA is usually connected to the output of 1310nm transceivers to amplify signal level before entering into optical fiber. It supports all format of 1310nm wavelength signals and is compatible with all data rates. Thus, SOA is an ideal solution for DWDM network optical amplification.

Conclusion

To sum up, optical amplifier enables the optical transmission over long distance by amplifying signals. This article introduces the fundamentals of its functions and some commonly used types. You may have an overall understanding about optical amplifier. For more information, please visit FS.COM.

Source:http://www.fiber-optical-networking.com/guide-optical-amplifier.html

What is Fiber Optic Isolator?

Fiber optic isolator is a passive component used for fiber optic communications. As a magneto-optic device, the purpose of optical isolator is to allow light to be transmitted in only one direction. This helps prevent laser source from unwanted feedback which will damage the laser source or arouse unexpected laser problems, such as mode hop, amplitude modulate, frequency shift and so on. Therefore, isolator is an useful and indispensable device to reduce these effects. In the following parts, fiber optic isolator’s construction, operating principle and classifications will be discussed.

Construction of Optical Isolator

Fiber optic isolator includes three main parts of an input polarizer, a Faraday rotator with magnet, and an output polarizer. Only linearly polarized light can pass through the input polarizer into the Faraday rotator. The function of the Faraday rotator is to rotate the input light by a certain angle before it reaches the output polarizer. This allows the light in the forward direction to pass unimpeded. However, the light in the reverse direction will not be able to pass the optical isolator and is either reflected or absorbed. These three components of optical isolator skillfully work together and ensure the normal transmission of light signals.

Operation of Optical Isolator

The operation of optical isolator is based on the Faraday effect which was discovered by Michael Faraday in 1842. Faraday effect refers to a phenomenon that the plane of polarized light rotates while transmitting through glass (or other materials) that is exposed to a magnetic field. The rotation direction depends on the direction of the magnetic field instead of the direction of light transmission.

According to different light directions, there are two types of operation modes. One is the forward mode and the other is the backward mode. The forward mode enables light enter into the input polarizer and become linearly polarized. When laser light reaches the Faraday rotator, the Faraday rotator rod will rotate by 45° polarization. Thus, the light finally leaves the output polarizer at 45° polarization. However in the backward mode, the light first enters into the output polarizer with a 45° polarization. Next, as it passes through the Faraday rotator, it continues to be rotated for anther 45° in the same direction. Then the light of 90° polarization becomes vertical to the input polarizer and can not leave the isolator. As a result, the light will be either reflected or absorbed.

Types of Optical Isolator

1) Polarized Optical Isolator

Polarized optical isolator employs the polarization axis to keep light transmit in one direction. It allows light to propagate forward freely, but disallows any light to travel back. Also, there are dependent and independent polarized optical isolators. The latter is more complicated and often used in EDFA optical amplifier.

2) Composite Optical Isolator

Composite optical isolator is actually a type of independent polarized optical isolator. It is used in EDFA optical amplifier which consists of many other components, such as erbium-doped fiber, wavelength-division multiplexer, pumping diode laser and so on. Since there are many other components in EDFA module, this type of isolator is named as composite optical isolator.

3) Magnetic Optical Isolator

Magnetic optical isolator is essentially the polarized optical isolator in another expression. It stresses the magnetic part of a Faraday rotator. The Faraday rotator is generally a rod made of a magnetic crystal under strong magnetic field with Faraday effect.

Conclusion

In summary, fiber optic isolator guarantees the stable function of laser transmitter and amplifiers by eliminating unnecessary lights. It also ensures a higher performance of light transmission. Using fiber optic isolator is no doubt a good choice for your network.

Source:http://www.chinacablesbuy.com/what-is-fiber-optic-isolator.html

Introduction to Simplex, Half Duplex and Full Duplex

Simplex, half duplex and full duplex are three kinds of communication channels in telecommunications and computer networking. These communication channels provide pathways to convey information. A communication channel can be either a physical transmission medium or a logical connection over a multiplexed medium. The physical transmission medium refers to the material substance that can propagate energy waves, such as wires in data communication. And the logical connection usually refers to the circuit switched connection or packet-mode virtual circuit connection, such as a radio channel. Thanks to the help of communication channels, information can be transmitted without obstruction. A brief introduction about three communication channel types will be given in this article.

Three Types of Communication Channel

1) Simplex

A simplex communication channel only sends information in one direction. For example, a radio station usually sends signals to the audience but never receives signals from them, thus a radio station is a simplex channel. It is also common to use simplex channel in fiber optic communication. One strand is used for transmitting signals and the other is for receiving signals. But this might not be obvious because the pair of fiber strands are often combined to one cable. The good part of simplex mode is that its entire bandwidth can be used during the transmission.

2) Half duplex

In half duplex mode, data can be transmitted in both directions on a signal carrier except not at the same time. At a certain point, it is actually a simplex channel whose transmission direction can be switched. Walkie-talkie is a typical half duplex device. It has a “push-to-talk” button which can be used to turn on the transmitter but turn off the receiver. Therefore, once you push the button, you cannot hear the person you are talking to but your partner can hear you. An advantage of half-duplex is that the single track is cheaper than the double tracks.

3) Full duplex

A full duplex communication channel is able to transmit data in both directions on a signal carrier at the same time. It is constructed as a pair of simplex links that allows bidirectional simultaneous transmission. Take telephone as an example, people at both ends of a call can speak and be heard by each other at the same time because there are two communication paths between them. Thus, using the full duplex mode can greatly increase the efficiency of communication.

Simplex Fiber Optic Cable vs. Duplex Fiber Optic Cable

A simplex fiber optic cable has only one tight-buffered fiber inside cable jacket for one-way data transmission. The aramid yarn and protective jacket enable the cable to be connected and crimped to a mechanical connector. It can be used for both single-mode and multimode fiber optic cables. For instance, single-mode simplex fiber optic cable is suitable for networks that require data to be transmitted in one direction over long distance.

Different from simplex fiber optic cable, the duplex one has two fibers constructed in a zipcord style. It is often used for duplex communication between devices to transmit and receive signals simultaneously. The duplex fiber optic cable is required for all sorts of applications, such as workstations, fiber switches and servers, fiber modems and so on. And single-mode or multimode cable is also available with duplex cables.

Conclusion

The concept of communication channel is important for understanding the operation of networking. Simplex, half duplex and full duplex are three modes of communication channels. Each of them can be deployed for different applications. It is more cost-effective to choose the right fiber optic cable according to its channel mode.

Source:http://www.fiber-optic-cable-sale.com/introduction-to-simplex-half-duplex-and-full-duplex.html