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Journey of Cables – From Coppers to Optical Fiber
Published in Vikas Kumar Jha, Bishwajeet Pandey, Ciro Rodriguez Rodriguez, Network Evolution and Applications, 2023
Vikas Kumar Jha, Bishwajeet Pandey, Ciro Rodriguez Rodriguez
An optical fiber or fiber-optic cable refers to that technology of communication which transmits data through thin strands of a highly transparent material, which is usually either glass or plastic. It was launched in the 1970s, but the first optical fiber telecommunications network was not installed until the early 1980s. The optical fiber cable is a high-speed data transmission medium of modern age communication that contains tiny glass elements within the cable coated with plastic layers to carry light beams. Its assembly is similar to that of an electrical cable, but in place of the metallic conductor, it contains one or more optical fibers that are used to the carry the signal in the form of light waves rather than electrical pulse in the electrical cable. The fiber elements of the optical fiber cable are individually coated with plastic layers that are further placed in a protective tube suitable for the transmission of light waves for data transmission.
Semiconductor Optical Fibers
Published in Inamuddin, Mohd Imran Ahamed, Rajender Boddula, Tariq Altalhi, Optical Properties and Applications of Semiconductors, 2023
Lele Zang, Qixun Xia, Zhijun Du, Nanasaheb M. Shinde
Generally speaking, the optical fiber is composed of core and cladding, which transmits the signal, and the cladding has different refractive indices with the core, so the optical signal is transmitted and protected in the core.
Optical Access Architecture
Published in Partha Pratim Sahu, Fundamentals of Optical Networks and Components, 2020
Optical fiber transmits up to 50 km or beyond in the subscriber access network. Figure 9.11 shows an FTTH access network in which a logical method accessing optical fiber in the local access network uses a point-to-point (PtP) topology. Three configurations are – dedicated fiber set from the CO to each end-user subscriber for bandwidth-intensive, integrated, voice, data and video services: (a) simple architecture having connector termination space curb switch connected to a Local Exchange (called as CO) with bidirectional fiber in which N subscribers are connected with a curb switch, (b) architecture having passive optical power splitter connected to the Local Exchange (called as CO) with bidirectional fiber in which N subscribers connect the curb switch at an average distance L kilometers from CO. A PtP structure has 2N transceivers and N × L total fiber length (assuming that a single fiber is used for bidirectional transmission).
Local water content field within an epoxy/metal bonded assembly in immersion
Published in The Journal of Adhesion, 2023
R. Grangeat, M. Girard, C. Lupi, F. Jacquemin
Optical fiber is a waveguide with the ability to conduct light. It generally consists of two concentric silica cylinders: the optical core and the optical cladding. The optical fibers used in this study are single-mode fibers (SMF28). In this study, two sizes of optical fibers will be used, one with a 125 µm optical cladding (produced by iXblue IXF-SM-1550-125) and one with an 80 µm optical cladding (iXblue IXF-SM-1550-80). In both cases, the optical core is 8 µm. All measurements will be performed using a laser with a wavelength of 1550 nm. By cleaving the end of an optical fiber it is possible to create a diopter. Following the laws of Snell-Descartes,[12] a portion of the incident wave is reflected by the diopter. By measuring the optical power of this reflection, it is possible to determine the refractive index of the environment where the diopter is positioned (cleaved end of the fiber).[13] This sensor, called a Fresnel sensor, allows to measure locally the index of refraction of a material, the measurement being carried out at the end of the optical fiber. It was shown in a previous study the possibility of measuring the local water content without calibration in an adhesive epoxy.[14] For this purpose, a model was used to relate the local refractive index to the local water content. Still with the aim of locally measuring the water content within the interfacial zone, bonded assemblies will be instrumented (Figure 2).
ACO–OFDM with Improved Bandwidth Efficiency over Long Haul and MIMO Optical Fiber Communication Systems
Published in IETE Journal of Research, 2022
Optical fiber has been an efficient transmission channel for high speed and long haul communication link up to transoceanic distances. It holds enormous data speed capacity with low environmental interferences. Basic optical fiber set-up consists of single-mode fibers for long distance high speed links where as multimode fiber is a low cost option for short distance, slower data rate applications [1]. Optical fiber links are backbone for links between telephone exchanges, Cable TV connections and base stations to remote node terminals in radio over fiber. Recent challenges for communication industry are related to network and device designing that can sustain for upcoming advancements in technologies and demands on user end. Cloud radio access network (C-RAN) for 5G requires a fair investment in point-to-point fiber link closer to the user end [2–4].
Development of sensing system for 3-dimensional mapping of underground optic fibre cable conduit
Published in Journal of Control and Decision, 2021
The optical fibre cables used as the main lines of the network are normally installed in underground conduits with one common process (single length cable blowing) demonstrated in Figure 1 (Fiber Optic Connector Identifier, 2019). The tip of the optic fibre cable rolled around a cable drum is fed into a cable blowing machine. Driven by pneumatic or hydraulic motors, the cable is pushed and installed into the underground conduits. The optic fibre cables are easily subject to damage if they are blown through a conduit with multiple turns and high bend radius. Thereby, the information of the underground conduit, such as the location and the maximum bend radii of the turns, the maximum elevation or depth, is critical for fibre cable blowing and installation. However, millions of ducts or conduits have been laid underground for decades, which have experienced drifts, bends, or inconsistent expansions introduced by the natural surroundings, such as temperature change, soil exploration. Meanwhile, human factors, such as poor documentation management and documentation updating whenever conduit rerouting occurs also results in the deficiency of the information of the underground conduits, which sets barriers for fibre cable blowing and installation. Thereby, an intelligent sensing system that is capable of reconstructing a precise 3D layout of an underground conduit is highly desired.