Tag: fiber optic cable

Fiber Optic Cable are usually used in two scenarios

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Fiber Optic Cable are used in applications where the optical signal is too strong and needs to be reduced. 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.
The attenuation level is fixed at 5 dB, which means it reduces the optical power by 5dB. This attenuator has a short piece of fiber with metal ion doping that provides the specified attenuation.
There are many different mechanisms to reduce the optical power, this picture shows another mechanism used in one type of variable attenuator. Here variable means the attenuation level can be adjusted, for example, it could be from 1 dB up to 20dB.

Fiber Optic Cable are usually used in two scenarios.
The first case is in fiber optic power level testing. Cable 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, Cable are permanently installed in a fiber optic communication link to properly match transmitter and receiver optical signal levels.
Optical Cable are typically classified as fixed or variable Cable.
Fixed Cable have a fixed optical power reduction number, such as 1dB, 5dB, 10dB, etc.
Variable Cable’ attenuation level can be adjusted, such as from 0.5 dB to 20dB, or even 50dB. Some variable Cable have very fine resolution, such as 0.1dB, or even 0.01dB.
This slide shows many different optical attenuator designs.
The female to female fixed Cable work like a regular adapter. But instead of minimizing insertion loss, it purposely adds some attenuation.
The female to female variable Cable are adjustable by turning a nut in the middle. The nut adjusts the air gap in the middle to achieve different attenuation levels.
The male to female fixed Cable work as fiber connectors, you can just plug in your existing fiber connector to its female side.
The in-line patch cable type variable Cable work as regular patch cables, but your can adjust its attenuation level by turning the screw.
For precise testing purposes, engineers have also designed instrument type variable Cable. These instrument type Cable 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.

WHEN WAS FIBER OPTIC CABLE INVENTED?

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There are many people who believe fiber optics are the future of communication in this country. And for good reason. Fiber optic cables are currently being used to send voice messages, images, videos, and more at the speed of light. The fiber rods are made of glass or plastic and have the capability of sending data quicker and more effectively than the old metal wires that have been used to do the same thing for many years now. But when and where were fiber optics first invented?
THE HISTORY OF FIBER OPTIC CABLES
The history of fiber optic cables actually dates back to the mid-1800s. While the cables themselves weren’t invented back then, the technology behind them was first researched when scientists and inventors like John Tyndall, Alexander Graham Bell, and William Wheeler started toying around with the idea of using the speed of light to transmit information. Over the next 100 years or so, other researchers continued to push forward with the idea of using light to send data before a group of Corning Glass researchers, including Robert Maurer, Donald Keck, and Peter Schultz, first invented fiber optic wires—then called “Optical Waveguide Fibers”—that could carry about 65,000 times more data than copper wires. It was a huge development.
The U.S. government was one of the first big organizations to start using fiber optic cables when they utilized them to link a network of computers together in the NORAD headquarters in Colorado in 1975. Two years later, the first telephone communication system using fiber optic cables was created in Chicago. And fiber optics grew from there. By the end of the 1990s, about 80 percent of the globe’s long-distance data traffic was transmitted through fiber optic cables, according to ThoughtCo. And the fiber optics craze continues today with many companies using it to transmit data quickly both within their own walls and out in the world.

Fiber Optic Cable Vs. Coaxial Cable

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When connecting data signals between components in a computer network, you may choose between fiber optic or coaxial cable. Deciding which is more appropriate for your use depends on the distance of your connection and the amount of data you will send.
Construction
Coaxial cables carry electrical signals with copper conductors.
Fiber optic cables contain a tiny strand of fiberglass about the size of a human hair, with an outer covering to protect it. Coaxial cables have a copper center conductor surrounded by an insulating material, a braided shield and a protective covering.
Distance
Low-loss fiber optic cables carry a signal for several miles before needing a repeater. Signal losses are high in coaxial cable, however, so you should use it only for short distances.
Amount of Data
Fiber optic cables carry far more information than coaxial cables. A fiber optic system can carry up to 10 giga, or billion, bits per second. Coaxial cable is limited to only 50 mega, or million, bits per second.

The Difference Between Types of Fiber Optic Cable

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What Are The Three Types Of Fiber Cable Available In Enterprise Networks Today?
There are three type of fiber cable in Enterprise networks today – Multimode, Singlemode, and Laser-Optimized Multimode. Which fiber cable is better? The answer depends on the parameters of the network: the applications the network will need to support over the next few years and the length of the links. It also depends on whether you are evaluating a new installation or upgrading from an installed base.
Historically there were three types of fiber cables commonly used in cabling systems: 62.5/125 µm multimode fiber (OM1), 50/125 µm multimode fiber (OM2), and singlemode fiber (OS1 or OS2). The other type of 50/125 µm fiber, optimized for low-cost 850 nm laser applications (OM3 or 4), in now probably the most common specified in cabling and LAN application standards worldwide.
The main performance difference lies in the fibers’ bandwidth, or information-carrying capacity, and in the power-coupling efficiency to light-emitting-diode (LED) sources. Bandwidth is actually specified as a bandwidth-distance product with units of MHz-km, and as the data rate goes up (MHz), the distance that data can be transmitted (km) at that rate goes down. Thus, a higher fiber bandwidth can enable you to transmit at higher data rates or for longer distances.
But while fiber bandwidth is important in determining link length and data rate, transmitter and receiver characteristics also play a critical role. Any statements on the distance capabilities of a particular fiber cable type must be made in the context of the full suite of specifications for a given application.
EXTENDING THE CAPABILITIES OF OPTICAL FIBER
There are multiple ways to extend the capability of the different types of fiber cable, some of which optical fiber standards have not yet make the most of:
Copper based-LANs for example use multi-level coding which increases transmission capacity and uses less bandwidth. This technique has yet to be used widely on multimode fiber cables.
Fiber cables can also take advantage of wavelength division multiplexing (WDM), which uses different colours/wavelengths of light across the same fiber to provide more channels.
Parallel transmission is another way of increasing link speeds, with multiple fibers used to transmit data. Also, devices such as short wavelength lasers and vertical cavity surface emitting lasers (VCSELs), are capable of providing cost-effective gigabit-rate data links over multimode fiber.
As network speeds continue to evolve ever higher, these new technologies and approaches will continue to be developed and deployed.
HOW DO YOU COMPARE MULTIMODE FIBER TYPES?
How fiber is qualified and tested should be one of the first questions asked in any situation. The bandwidth of a fiber is always specified in MHz-km and at specific wavelengths (i.e. 850 nm); however, test methods differ.
Historically, multimode fiber was tested and bandwidth specified using the OFL (Overfilled Launch) method. This method was optimized for use with LEDs. But as the gigabit networking era kicked in, lasers (VCSELs) were needed to transmit speeds above 1 Gbps, so a new test method was required called DMD (Differential Mode Delay).
In the DMD process, a laser is used to transmit pulses across the entire fiber core. As each of these pulses is received by a high-speed detector at the far end, the pulse delay is plotted and the DMD is calculated. This process is automated and covers all laser launch modes.
It is important to note that “laser” bandwidth, also referred to as Effective Modal Bandwidth (EMB), is NOT the same as “overfilled” bandwidth (OFL). For instance, 50 micron multimode fiber with an OFL bandwidth of 500 MHz-km at 850 nm does not automatically equate to a laser bandwidth of 500 MHz-km; that can only be proven by laser testing.
The standard DMD measurement process involves scanning the output from a singlemode fiber across the core of the sample multimode fiber core in radial launch positions separated by incremental steps of 2 µm. Some DMD testing facilities use a more precise laser and extract even higher resolution information by reducing the step size to 1 µm, effectively doubling the number of scanning positions. It has been shown that this ‘High Resolution DMD’ provides greater assurance of adequate bandwidth for a wider set of fibers and laser launch conditions. As vendors look for looser laser specifications to reduce cost for 10G, 40G and 100G optoelectronics, HRDMD will become more important.

Very Effective Method of Fiber Optic Cables Selection

After the distribution network plan is developed, the next step we have to do is the selection of the right fiber optic cable. Remember the bulk of the Fiber Optic Cable installed today is for either telephone or office applications. Industrial sites bring some challenges that are not address by many of the common fiber optic cable installation design. Just due to the local telephone company would rather a particular type of fiber optic cable does not mean it is the right one for a facility.

After the distribution network plan is developed, the next step we have to do is the selection of the right fiber optic cable. Remember the bulk of the Fiber Optic Cable installed today is for either telephone or office applications. Industrial sites bring some challenges that are not address by many of the common fiber optic cable installation design. Just due to the local telephone company would rather a particular type of fiber optic cable does not mean it is the right one for a facility.

The common rule of thumb for selection optical cable in industrial setting is to use 62.5/125 μm or 50/125 μm Multi-mode fiber cable. The cable should be rated for both indoor and outdoor use and must have an FT-4 flame rating if it is used for indoors. Aluminum interlock armor is preferred over steel tape for all but long, buried runs. Fiber counts should be a minimum of 12, with 24 fibers as the standard for main backbones. More specific selection details depend on the area where the cable will be installed.

Indoor Office Installation

Fiber selection for office applications is relatively simple. The fiber must be flame-rated for either FT-4 general use or FT-6 for plenum. Typically, tight-buffered cable with Kevlar strength members and a light jacket is used. There is little reason to use loose tube as it is more difficult to install and usually does not meet the flame rating standards. As well, fiber optic cables in these environments do not require armor as the chance of crush or pull damage is relatively low. Because jacketed fiber optic cable is more rugged than most coaxial and twisted-pair cables, plan to armor fiber only in the places where coaxial cables would be Armored Fiber Cable.

Indoor Industrial Installations

If fiber optic cable is being installed in plant-floor conditions. It is possible to be installed in existing cable trays and be subjects to more stresses than office cable systems. Thus, some form of armor is recommended, usually aluminum interlocked (TEC style) armor. This armor must be electrically bonded to ground at all distribution cabinets.

Inter-building Installation

Industrial sites often need a combination of indoor and outdoor fiber routing. Telecommunication industry guidelines recommended switching between indoor and outdoor fiber cable types at each transition, a solution than is not practical for most industrial sites. On a typical site, this would require numerous patch boxes or splices and is not worked for both cost and attenuation(signal loss) reasons. Instead, FT-4 flame-rated, tight-buffered cable should be used so that the cable can transmit both indoor and outdoor environment.

Long-Run Outdoor Installations

Outdoor fiber cable generally falls into three categories, direct burial, underground conduit, and aerial. These cables are manufactured specifically for outdoor applications and are recommended for any long outdoor cable runs, especially in region subject to cold weather. Most are loose tube designs with high tensile strength, to withstand environmental conditions, and gel filling, to prevent water migration. The jacket materials are specially selected to be abrasion and ultraviolet resistant. If a facility is planning to install long outdoor runs it will need to work closely with the manufacturer ti determine the right cable for its application.

Indoor and Outdoor fiber optic cable delivers outstanding audio, video, telephony and data signal performance for educational, corporate and government campus applications. With a low bending radius and lightweight feature, this cable is suitable for both indoor and outdoor installations. Typical indoor and outdoor cables are loose tube and tight buffer designs, and we also supply ribbon cables, drop cables, distribution cables and breakout cables. These are available in a variety of configurations and jacket types to cover riser and plenum requirements for indoor cables and the ability to be run in duct, direct buried, or aerial/lashed in the outside plant. In addition, Fiber-Mart can supply Indoor and Outdoor fiber optic cable. If you have any questions or requirement of Indoor and Outdoor fiber optic cable，welcome to contact us: product@fiber-mart.com.

The Advantages and Disadvantages of Optical Fiber

Driven by the rising demand for higher bandwidth and faster speed connections for a variety of industrial and residential purposes, fiber optic transmission is becoming more and more common in modern society. In this tutorial, the advantages and disadvantages of fiber optic transmission will be explored in details.

Driven by the rising demand for higher bandwidth and faster speed connections for a variety of industrial and residential purposes, fiber optic transmission is becoming more and more common in modern society. In this tutorial, the advantages and disadvantages of fiber optic transmission will be explored in details.

Fiber Optic Transmission Technology

Usually, a fiber optic communication system consists of three main components: optical transmitter, fiber optic cable and an optical receiver. The optical transmitter converts electrical signal to optical signal; the fiber optic cable carries the optical signal from the optical transmitter to the optical receiver; and the optical receiver reconverts the optical signal to electrical signal. The most commonly used optical transmitter is semiconductor devices like LEDs (light-emitting diodes) and laser diodes. Photodetector is the key part of an optical receiver. It converts light into electricity using photodetector effect. As for the fiber optic cable, there is too much to say. As the use and demand for speed and bandwidth, the development of optical cables is amazing. Now in the optical cable market, there are OS2 fIber, OM1 fIber, OM2 fIber, OM3 fIber, OM4 fiber and OM5 fiber cable for different optical applications. Optical fibers are used as a medium for telecommunication and networking because it is flexible and can be bundled as cables. It is especially advantageous for long-distance communications, because light propagates through the fiber with little attenuation compared to electrical copper cables. The figure below shows that all fiber optic transmission systems use modulated light to convey information from a transmitter to a companion receiver.

Advantages and Disadvantages of Optical Fiber

Given the speed and bandwidth advantages optical fiber has over copper cable, it also contains some drawbacks. Here are advantages and disadvantages of optical fiber cable.

Advantages of Optical Fiber

Greater Bandwidth & Faster Speed—Optical fiber cable supports extremely high bandwidth and speed. The amount of information that can be transmitted per unit of optical fiber cable is its most significant advantage.

Cheap—Several miles of optical fiber cable can be made cheaper than equivalent lengths of copper wire. With numerous vendors swarm to compete for the market share, optical cable price would sure to drop.

Thinner and Light-weighted—Optical fiber is thinner, and can be drawn to smaller diameters than copper wire. They are of smaller size and light weight than a comparable copper wire cable, offering a better fit for places where space is a concern.

Higher carrying capacity—Because optical fibers are much thinner than copper wires, more fibers can be bundled into a given-diameter cable. This allows more phone lines to go over the same cable or more channels to come through the cable into your cable TV box.

Less signal degradation—The loss of signal in optical fiber is less than that in copper wire.

Light signals—Unlike electrical signals transmitted in copper wires, light signals from one fiber do not interfere with those of other fibers in the same fiber cable. This means clearer phone conversations or TV reception.

Long Lifespan—Optical fibers usually have a longer life cycle for over 100 years.

Disadvantages of Optical Fiber

Limited Application—Fiber optic cable can only be used on ground, and it cannot leave the ground or work with the mobile communication.

Low Power—Light emitting sources are limited to low power. Although high power emitters are available to improve power supply, it would add extra cost.

Fragility—Optical fiber is rather fragile and more vulnerable to damage compared to copper wires. You’d better not to twist or bend fiber optic cables.

Distance—The distance between the transmitter and receiver should keep short or repeaters are needed to boost the signal.

How to Select the Right Optical Fiber Cable?

Optical fiber has gained much momentum in communication networks, and there emerges a dazzling array of vendors competing to manufacture and supply fiber optic cables. When selecting optical fiber, you’d better start with a reliable vendor. Here’s a guide to clarify some of the confusions about choosing fiber optic cable.

Check manufacturer qualification

The major optical cable manufacturers should be granted ISO9001 quality system certification, ISO4001 international environment system certification, the ROHS, the relevant national and international institutions certification such as the Ministry of Information Industry, UL certification and etc.

Choose cable jacket

The standard jacket type of optical cable is OFNR, which stands for “Optical Fiber Non-conductive Riser”. Besides, optical fibers are also available with OFNP, or plenum jackets, which are suitable for use in plenum environments such as drop-ceilings or raised floors. Another jacket option is LSZH. Short for “Low Smoke Zero Halogen”, it is made from special compounds which give off very little smoke and no toxic when put on fire. So always refer to the local fire code authority to clarify the installation requirement before choosing the jacket type.

Indoor vs. Outdoor

The choice greatly depends on your application. The major difference between indoor and outdoor fiber cable is water blocking feature. Outdoor cables are designed to protect the fibers from years of exposure to moisture. In a campus environment, you can get cables with two jackets: an outer PE jacket that withstands moisture and an inner PVC  jacket that is UL-rated for fire retardancy. You can bring the cable into a building, strip off the PE jacket and run it anywhere, while normal outdoor cables are limited to 50 feet inside the building.

Fiber count

Both indoor and outdoor fiber cable have a vast option of fiber count ranging from 4-144 fibers. If your fiber demand exceeds this range, you can custom the fiber count for indoor or outdoor optical cable. Unless you are making fiber patch cords or hooking up a simple link with two fibers, it is highly recommended to get some spare fibers.

Conclusion

Obviously, advantages of optical fiber communication in various aspects contribute to the rapid development of optical fiber communication. Although it’s still with some disadvantages, and it will be improved with the future development of tech. Let’s expect it together.Fiber-mart is a renowned vendor that committed to develop and supply optical fiber of all types, including fiber patch cable, indoor/outdoor optical cable and FTTH fiber optical cable, etc. Each of our fiber optic cable is tested in strict environment to deliver excellence in performance and reliability. Optical fiber custom service is also available in Fiber-mart, so you can make your unique fiber optic cable in according to your specific needs. Moreover, our global inventory system enables fast same-day shipping that will greatly shorten your waiting time. If you have any questions or requirement of Optical Fiber, welcome to contact us: product@fiber-mart.com.