High-speed data transmission for industrial applications
IDC predicts that by 2027, the volume of data created and replicated will reach 284 zettabytes, a 21-zero figure, threatening the Internet of Things without a nationwide broadband expansion, highlighting the need for significant data storage and replication.
The first transatlantic fiber-optic cable was operational in 1988, enabling high-speed data transmission between continents. The mid-1990s saw broadband expansion, adding more long-distance routes and moving fiberglass transmission paths closer to end devices like data centers, industrial plants, and personal computers, known as the “last mile.”
Data transmission across continents, countries, and municipalities requires high security and reliability, with speed, immunity to interference, and failsafe performance being basic requirements for industrial and semi-industrial data transmission.
Fiber-optic cables (FO) transmit data in light over long distances by converting electrical signals into photon packets and sending them to the receiver via plastic or fiberglass. The light signals are then converted back into electrical signals for evaluation and processing.
The article explores the advantages of data transmission through fiber-optic cables over copper transmission, focusing on their characteristics.
Speed and distances
Fiber-optic cables use photons to transmit electrical signals, which are faster than electrons in copper conductors. Photons can travel up to 70% of the speed of light, with minimal signal loss. This allows for longer transmission distances of up to 50 km and data rates of up to 40 Gbps. The actual range depends on the chosen fiber-optic cable, making them suitable for long distances and large data volumes.
Reliability and security
Fiber-optic cables are reliable for data transmission due to their non-conductive cores made of glass or plastic, eliminating the need for complex shielding. They are metal-free, insensitive to EMC and ESD interference, allowing parallel use with other cables. Impedance problems and crosstalk are not issues. Fiber-optic cables with coatings are better protected against environmental influences.
Fiber-optic cables offer enhanced cybersecurity due to their lack of external signals, requiring direct access via bend connectors or contact points, making them significantly more secure against eavesdropping than copper cables, despite not providing 100% protection against unauthorized access.
Costs
Fiber-optic technology has disadvantages such as complex assembly, precision, expensive equipment, complex measurement technology, and well-trained specialists. Manufacturing and monitoring production are costly and require extensive expertise in this specialist field.
Fiber-optic data transmission cables are suitable for industrial and semi-industrial automation, spanning short, medium, and long distances, at speeds of 100 Mbps to 40 Gbps, and within bus or Ethernet structures. They can withstand harsh conditions, even on wind farms, and are up to 90% lighter and thinner than copper cables.
Fiber optic cables have various applications in vehicle technology, industrial cabling, data centers, wide area networks, and FTTH (Fiber To The Home), with selecting the right type and fiber category is crucial.
Fiber types
Differentiating between fiber types is crucial, as singlemode and multimode fibers are not compatible due to different core and cladding diameters.
POF for short transmission distances up to 100 m and up to 50 Mbps
POF cables, made of plastic core and cladding, are used in automotive engineering and industrial cabling for short transmission distances up to 100 meters and data rates of up to 50 Mbps. They are easy to assemble in the field due to their robustness, but not suitable for high data rates or long distances.
PCF for medium transmission distances up to max 2,000 m and up to 100 Mbps
Polymer-clad fibers (PCFs) are glass-coated fiber-optic cables, commonly used in industrial cabling with medium lengths of up to 500 meters and data rates of ≤100 Mbps. They are robust and easy to assemble, with applications in automotive, sensors, and medical technology.
GOF multimode for long transmission distances up to 550 m at up to 10 Gbps
With core widths of 50 µm or 62.5 µm and cladding diameters of 125 µm, GOF multimode cables have a quartz core encircled by reflective glass cladding.
Greater light energy coupling at the fiber’s commencement but greater attenuation along its length are made possible by GOF multimode fibers’ bigger core diameters, which makes them perfect for data centers and local area networks.
GOF singlemode for long transmission distances up to 50 km and up to 40 Gbps
Glass optical fiber (GOF) singlemode fibers have a smaller core diameter of 8 µm and a mode field diameter based on wavelength. They can transmit a large amount of signal light due to their single light mode and low attenuation coefficient. These fibers are ideal for distances up to 50 km and data rates up to 40 Gbps.
Cable types
Fibers are protected in robust cables to prevent mechanical stress and environmental influences. Indoor cables must be fire-resistant to prevent smoke and toxic gases. Outdoor fiber-optic cables need high robustness for long service life. They should be weatherproof, moisture-resistant, UV-resistant, and stable against mechanical strain. The cable type used depends on the application structure.
Loose tube cables
Loose tube cables contain numerous GOF fibers in one cable, protected by a coating and reaching a 250 µm diameter. These fibers are bundled in tubes, usually coated with a water-repellent gel, and can have up to 24 fibers combined in one tube, enabling high fiber density at a small diameter.
Loose tube cables’ connectors cannot be directly mounted on fibers, instead using fiber-optic pigtails for connection, unlike breakout cables.
A pigtail is a fiber-optic connector with a preassembled plug on one end and spliced to the incoming cable’s fibers on the other open-end side
Loose tube cables are designed for harsh environments with high tensile strength and well-decoupled fibers. Loose tube cables are suitable for temperature fluctuations and high humidity environments. Available as outdoor and universal cables, they are suitable for both indoor and outdoor use.
Breakout cables
Breakout cables are splitable fiber-optic cables with individual single-core elements housed in a shared protective cable cladding. They were developed to avoid or replace on-site splicing work, as FO connectors can be mounted directly onto the cables. They can be used as patch cables or for laying cables by the meter between points in the field.
Mini breakout cables
Mini breakout cables with GFO fibers feature 900 µm diameter wires in a shared cable cladding, providing protection from external influences. Ideal for future-proof cabling of distributors and junction boxes, these universal cables are suitable for both indoor and outdoor applications.
Duplex cables
Fiber-optic duplex cables with GOF fibers consist of two 900 µm diameter wires, each routed separately. Preassembled at both ends, they allow direct connection to active and passive components. Wide connector combinations and fiber categories offer various applications.
Fiber categories
Fiber-optic cables are categorized into categories such as “OM3” and “OS2” based on their attenuation coefficient and bandwidth length product. Single mode fibers are in OS1 and OS2, while multimode fibers are in OM1, OM2, OM3, OM4, and OM5.
Transmission rates and ranges by category
Connection technologies and characteristics
Connection technologies
The table provides an overview of various connection technologies and their characteristics for fiber-optic cables, including splices and connectors, which are suitable for connecting cables and other components.
Fusion splicing
Fusion splices are non-detachable connections between optical fibers, used for connecting loose tube cables to distributor boxes, repairing fiber breaks, and routing factory-assembled patch cables. They are durable and have minimal attenuation. However, they require trained specialists and special equipment, such as a fusion splicer with fiber processing tools, for proper handling.
Mechanical splicing/field assembly
Mechanical splicing involves connecting two fibers in a special V-groove or sleeve, ensuring clean and straight ends. Fill the space between the fiber ends with an index-matching gel to match refractive indices. With identical GOF optical fibers and precise coupling, attenuation is approximately 0.2 dB. Connectors for field assembly, end sockets, connection housings, and repair purposes utilize mechanical splicing, particularly for fiber-optic cables.
Plug-and-play connectors
Connectors with GOF (Gorilla Glass) are flexible, easy to disconnect, and secure, requiring no trained specialists or equipment. However, they have higher losses of 0.2 to 0.5 dB and lower durability compared to splice connections. There are various connectors with different characteristics and applications, with an overview of the most important ones.
Transmission rates and ranges by category
Communications engineering and IT primarily use fiber-optic cables for data transmission due to their long ranges and high transmission rates. These cables have been extensively tested and qualified for harsh ambient conditions. Due to their exceptional characteristics, small dimensions, and flexibility, fiber-optic cables are also attractive for other industries. Including building infrastructure, factory automation, and data centers. Applications include control signals, machine communication, Industry 4.0, and artificial intelligence.
Fiber-optic cables are versatile tools for data transmission, with potential applications in medical technology, measurement technology, and even in harsh conditions like wind farms. They transmit data for monitoring usage, performance, and capacity utilization, ensuring reliable performance and efficiency in these critical applications.
Splice distributors, also known as splice boxes, serve as a transfer point between passive and active components for FO cabling. They also terminate loose tube cables, with fiber type selection based on link length and data rates.
