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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
Transmission medium is an essential component of a network along with a transmitter and a receiver without which the communication cannot be completed. The transmission medium is a component that serves the purpose of telecommunication by giving a path to data signals to pass through and transmit from one place to another. Therefore, the transmission medium can be said as the highways or arteries of telecommunication. Transmission media are either wire-lined or wireless; copper cables and optical fiber cables are popular types of the wireline medium. Both the copper cable and optical fiber cable can provide connectivity to homes and business with the Internet. But nowadays, optical fiber cables seem to be more and more popular and efficient in data centers requiring high data speed [1]. Optical fibers have several advantages and can provide greater bandwidth and longer transmission distances with low signal losses. The optic fiber cable is regarded as the best transmission medium since its introduction. This technology works by fiber cables made of glass or plastic strands which can transmit light. This technology allows the data or voice signals to go through the cables as the beam of light rather than electrical signals. This can deliver more data and has good quality of signals or increased degree of integrity over longer distances as compared to copper cables. Optical fibers are immune to electrical interference or noise/disturbances, making them more reliable and safer. This is the reason that most of the connections between servers have been replaced with optical links in data centers.
N
Published in Philip A. Laplante, Comprehensive Dictionary of Electrical Engineering, 2018
nodal cell nodal cell cell with a radius of up to 300 m. Typically an isolated cell acting as a high capacity network node. See also cell. nodal system a secondary system of equations using nodal voltages as variables. node a symbol representing a physical connection between two electrical components in a circuit. See also graph. node analysis a circuit analysis technique in which KCL is used to determine the node voltages in a network. noise (1) any undesired disturbance, whether originating from the transmission medium or the electronics of the receiver itself, that gets superimposed onto the original transmitted signal by the time it reaches the receiver. These disturbances tend to interfere with the information content of the original signal and will usually define the minimum detectable signal level of the receiver. (2) any undesired disturbance superimposed onto the original input signal of an electronic device; noise is generally categorized as being either external (disturbances superimposed onto the signal before it reaches the device) or internal (disturbances added to the signal by the receiving device itself). See also noise figure, noise power ratio. Some common examples of external noise are crosstalk and impulse noise as a result of atmospheric disturbances or manmade electrical devices. Some examples of internal noise include thermal noise, shot noise, 1/f noise, and intermodulation distortion. noise bandwidth an equivalent bandwidth, W N , of a system expressed as WN =
Communication Techniques
Published in B K Bala, Energy Systems Modeling and Policy Analysis, 2022
A transmission medium is a pathway that carries information signals from a transmitter to a receiver (plural: transmission media). This pathway may be a solid, a liquid or a gas. Typical pathways are copper or fiber-optic cables and the atmosphere or a vacuum. Information signals can be electrical, electromagnetic or optical. The transmission medium for sound received by ear is usually air. A vacuum or empty space is also a transmission medium for electromagnetic waves such as light and radio waves.
Dingo Optimizer Plus Black Widow Optimization-Based Optimal Design of Multiband U-Slot Microstrip Patch Antenna
Published in Cybernetics and Systems, 2023
Similarly, an analysis of the reflection coefficient is observed in Table 4. “The reflection coefficient is a parameter that describes how much of an electromagnetic wave is reflected by an impedance discontinuity in the transmission medium. It is equal to the amplitude of the reflected wave to the incident wave, with each expressed as phasors and denoted by the symbol gamma ” Initially, when the frequency is at 1 × 109 GHz, the reflection coefficient values for conservative and developed models are higher. However, there is a sudden drop in reflection coefficient values when the frequency reaches 1.25 GHz. After 1.26 GHz, the reflection coefficient values increase steadily when distinguished over other models. The examination of return loss is scrutinized from Table 5. Indeed; the return loss should be negligible for improved performances of U-slot MPA. A maximal return loss is observed at 1.25 GHz.
Optimized microstrip fractal antenna via hybrid EHO and GWO framework
Published in International Journal of Modelling and Simulation, 2022
Sanish V S, Stephen Rodrigues, Vishnupriya T R, Peter Cyriac
‘The reflection coefficient is a parameter that describes how much of an electromagnetic wave is reflected by an impedance discontinuity in the transmission medium. It is equal to the ratio of the amplitude of the reflected wave to the incident wave, with each expressed as phasors & is denoted by the symbol gamma ’. On examining the reflection coefficient in Figure 16, the proposed method outperformed the other models that were being compared. At the frequencies of 1.75 × 109, the adopted fractal carpet antennas design is 33.33%, 33.33%, 33.33%, 42.86%, and 42.86%, superior than conventional approaches such as EHO, GWO, MFO, and PSO. In addition, the reflection coefficient measure attained for fractal gasket antenna has yielded a higher value for chosen method than the compared approaches for all frequency ranges. Overall, the effectiveness of the suggested work has been demonstrated against other methods.
Research on the efficiency of multiphase wireless power transfer system with phase-shift control and magnetic field superposition
Published in International Journal of Electronics, 2021
Wireless Power Transfer (WPT) is a new technology of energy transfer. The traditional power transfer system is physically connected through metal, which is possible to cause electric shock and leakage. (Dai, 2010) On the contrary, WPT is a safe and reliable power transfer method, because it works on the principle of alternating magnetic field with no wire connection. With the maturity of WPT technology and its development in power electronic devices, power conversion and control technology, the application of WPT is gradually becoming a reality in aerospace, power systems, electric vehicles, mobile equipment, medical electronics and other aspects. Electrical appliances acquired energy from a fixed grid in a non-contact form, such as electromagnetic coupling, microwave, electromagnetic resonance, radio frequency and so on. Electromagnetic Resonance performs a great superiority above them, such as relatively low electromagnetic radiation, long transmission distance, small dependence on the transmission medium and low directivity requirements.