Optical fiber is the promising technology of the future. In the United States, the most extensive fiber-optic network utilization belongs to AT&T Inc. and Verizon Communications Inc., together producing over 2.2 million route miles. For several years, the demand for fiber optic services has been steadily increasing, making it worthwhile to get acquainted with optical fibers’ dynamics, their types, and construction. The practical use of optical fibers during installation works requires more technical knowledge and precision than standard twisted-pair cables.
It is said that optical fiber is the melody of the future. Its use in telecommunications services is continuously growing, allowing recipients to use high-speed data transmission, previously unattainable on traditional lines. Optical fibers are reaching an increasing number of households in the United States.
What are fiber optic jumpers?
Fiber optic jumpers also referred to as fiber patch cords are flexible cables consisting of single optical fibers to connect devices and systems based on optical fiber transmission. The jumper is often used in a system with frames or panels connected by multiple patch cables. Each has numerous jumpers that may be located near similar frames or panels, creating confusion in cable management.
Fiber optic jumper cables are generally long and extend across different rooms. Communication hubs use fiber patch cords to connect optical fibers in one place to other optical fibers at a remote location.
To put it simply, a fiber patch cord is a cable used to transmit optical signals. Typically, it consists of a wire that has a standardized length. On each side, the cable has tips compatible with a specific technology. We use fiber optic jumpers primarily in connecting active elements, such as switches and routers.
Fiber Optic Safety
Each telecommunications company and manufacturer of fiber optic equipment takes user safety very seriously. The protection of health and safety is ensured by numerous international research and regulatory organizations.
The safety of residents, such as in single-family housing, is not endangered by fiber optic technology. There are no scientifically documented cases of exposure to health or life from installing fiber-optic networks in a residential building. There are also no premises indicating the need for additional research and analysis of the issue.
The above considerations completely ignore the risk that may arise in the case of improper fastening or execution of network elements. The risk of fiber-optic technology is related to inadequate protection of the equipment, installation methods, or selection of components, not the result of the network’s nature. It’s essential to use the highest quality products from proven manufacturers to build safe fiber-optic networks.
Fiber Optic Cable Construction
Fiber optic transmission medium is based on a mode structure where the delivery mechanism is light. Optical fibers can also be categorized by fiber geometry and refractive index distribution. There are single-mode and multimode optical fibers on the market, which differ from one another in terms of thickness of the glass core responsible for the information transfer parameters.
Types of Fiber Cables
Single-mode Fiber
Single-mode optical fibers consist of a core with a diameter of approximately 9 +/- 2 µm, characterized by a step-change in the refractive index. The optical fiber cladding is standardized, and its diameter is 125 µm. Single-mode fibers undergo low intermodal dispersion, which causes slight interference. The light wave’s course runs almost parallel to the fiber’s axis, reaching the fiber’s end in raw mode.
Thanks to the possibility of using many protocols simultaneously, low attenuation, and a small diameter of the core, single-mode fibers are perfect for long-distance information transfer – even up to 75 miles without the need to use a repeater regenerating the signal. Single-mode fibers allow for signal transmission in xWDM technology (flow at the level of Tb / s). There are four basic types of optical fibers in single-mode optical fibers.
Multimode Fiber
Multimode optical fibers are equipped with a much larger core, measuring 50 µm in diameter (old OM1 constructions even measured 62.5 µm in diameter). Their sheath’s diameter is standardized and most often amounts to – similarly to single-mode optical fibers – 125 µm. The transmission of a signal of the same wavelength in multimode optical fibers relies on its scattering between multiple modes. The speed in relation to the waveguide may be different, leading to a reduction in speed or transmission distance.
The decrease is due to wave impulse distortion. Multimode fibers allow for effective signal transmission up to a distance of approximately 1.2 miles, depending on the quality and class of optical equipment. Above this distance, it is necessary to use signal repeaters. Multimode optic fibers currently consist of three basic types of fibers.
Fiber Optic Jumper Construction
Generally, optical fibers consist of three basic components: core, cladding, and covering.
Optical fiber core
The optical fiber core is the key working element that enables the transmission of the light wave. The optical fiber core is a continuous hair-thin strand and can be made of crystalline materials, quartz, glass, or polymers.
Optical fiber cladding
The optical fiber cladding is the most critical protection of the core and is a barrier to the transmitted light wave, providing a refraction threshold.
Optical fiber Jacket
The optical fiber coverage is the outermost layer of the cable. This element is used to protect the optical fiber inside against mechanical damage and microcracks that could arise during the installation or transport of cables. The optical fiber covering is usually made of polyethylene, PVC, or polyamides resistant to moisture, extreme temperatures, and UV radiation. It is made in a multi-layer construction, which cushions the cable and absorbs kinetic energy more effectively.
Coding
Due to the large variety of types, construction, and origin of the fiber optic cable manufacturer, it is necessary to use the appropriate nomenclature to define the type and parameters of the cable. The biggest problem that complicates the marking of fiber optic cables is the use of three different color-coding systems.
Markings of optical fiber cables are applied to the outer sheathing. Their correct recognition and decoding are crucial for the quality of the technical documentation prepared, the efficiency of the design process, and the safety and efficiency of installation works.
Markings of optical fiber cables provide information on the type of cable structure, the type of seal, the type of outer sheathing materials, the type and number of fibers inside the cable, and the cord’s strength parameters. On the exterior sheathing of the fiber optic cable, you will find the manufacturer’s name, the length from the beginning of the section, as well as additional symbols related to the intended use of the cable.
A significant problem in the coding of fiber optic cables is that the manufacturer’s marking differs from the markings adopted by a given classification system, which can often mislead the designer, contractor, or investor. How to deal with it? Always pay attention to the coding order, bearing in mind that some symbols related to the cable structure may be missing from the marking for some cables.
Data Transmission
In 1880, an engineer from Concord (Massachusetts, USA), William Wheeler, constructed and patented a structure he called light piping. This was probably the first serious attempt to guide light in a glass medium. Wheeler planned to use his idea to illuminate the interior of buildings, but the bulb invented by Edison eliminated the idea as too complicated and impractical.
Fiber optic transmission consists of guiding optical rays generated by light sources through the glass fiber. Due to the low attenuation, no influence of the external electromagnetic field on the signal, and other advantages, optical fiber is currently the best transport medium for modern transmission lines.
The transmission consists of connecting an optoelectronic transmitter with an optoelectronic receiver through an optical fiber. LEDs or LD laser diodes are currently used as transmitters. Photodiodes are used as receivers.
Why Fiber?
Optical fibers are the best data transmission medium at the moment. They are slowly but surely replacing classic electric cables in practically all areas of data transmission, starting with telecommunications networks and ending with CCTV.
In terms of parameters, the fiber optic cable is superior to the classic electric cord in all respects. Optical fibers are characterized by very low attenuation, which allows cables to be routed over long distances without the need for signal regeneration systems.
They have enormous information capacity compared to electric wires – they can transmit much more data simultaneously. At the same time, light is the information carrier in optical fibers, which means that they are entirely immune to electromagnetic interference. This means that they can be used in any configuration, without fear that they will induce unwanted noise signals between them.
An additional advantage of the fiber optic cable is the process of digitization of the world, which already affects practically every aspect of our lives. Optical fibers are designed so that they cooperate with digital systems. Systems based on optical fibers are characterized by the fact that they can be easily enlarged compared to those operating on electric cables.
The attractiveness of fiber optic technology is compounded by the truth that we cannot fully use its potential. The upper limit of the bit rate is set by the detectability and interpretation of electronic equipment. There is a very good chance that the digital systems will still use the same cables in ten or even twenty years, and the speeds will be incomparably higher.
All these features are available at a very affordable price. It is worth considering the choice of optical fibers because the electrical cables used in data transmission will sooner or later die a natural death.
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