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Problems of Compensation and Adjustment
Published in Boris Levin, Antenna Engineering, 2017
The first distinction of the offered antenna from the known antennas is its use of the phone’s ground (chassis) as a radiator. This suggestion was made in [87]. The phone’s ground is a rectangular metal plate, whose length is close to a quarter of a wave length at the main operating frequency. This distinction permits to integrate the antenna with ground, removing the need for an installation of a separate antenna and a special metal counterpoise. Components of radio transmitter and receiver can be mounted on the metal antenna, which replaces the ground for those elements. Filters, placed on this plate, may provide a short circuit for direct currents and insulation (interruption) of circuit at high frequency.
Multi-folded Antennas, Perpendicular to Metal Surface
Published in Boris Levin, Wide-Range and Multi-Frequency Antennas, 2019
It is useful to compare the characteristics of the proposed antenna with the characteristics of a symmetric dipole. But first we need to clarify that the calculated and experimental results for the considered models were obtained, assuming that the models use the entire area of the personal phone casing. This assumption is based on uniting an antenna with ground and elimination of a separate antenna and a counterpoise. Components of radio transmitter and receiver can be mounted on the metal antenna, which replace the ground for those elements. Filters, placed on this plate, provide short for direct current and insulation at high frequency.
Power Line Communication Electromagnetic Compatibility Regulations
Published in Lars T. Berger, Andreas Schwager, Pascal Pagani, Daniel M. Schneider, MIMO Power Line Communications, 2017
Andreas Schwager, Lars T. Berger
Communication (low-voltage [LV] signalling) and high-power applications have the potential to cause interferences if EMC is not regulated. The first ‘EMC regulation’ was established in Prussia in 1892, according to [1]. It clarified that establishing and operating telegraph equipment is only allowed by authorities, and in the case of interference, placed the cost of eliminating interference on the owner of the most recent installation. In 1908, the law was amended to also regulate wireless transmissions. The first interference complaints occurred in innovative cities in the 1890s, where tramcars and telegraph links had been installed. The next complaints arose when railway signalling lines were influenced by power transmissions. Soon railway operators, energy utilities and telecommunication suppliers were seeking regulations. Medical radiation therapy equipment emerged as a source and sink of EMC issues. The world’s first commercial radio station was created by the Westinghouse Electric Corporation in 1920 in Pittsburgh, Pennsylvania, United States. Since then, the electromagnetic interference (EMI) of tramcars frequently interrupted radio broadcast services. Also in the 1920s, rotary dial phones converted an EMC victim to an EMC source. In these early days, power transmission lines were also used for transmitting radio programmes. In Norway, this technique was called Linjesender, and the radio programme was fed into the lines by special transformers. Filters for carrier frequencies used by transmission systems were installed in substations and at line branches, in order to prevent uncontrolled propagation. It is probable that the EMC of electric engines stopped this technology. The short-wave (SW) radio receivers use the mains as counterpoise to the monopole whip antenna. When utilising one and the same media for various applications, of course EMC has to be considered with great care. In World War II, another EMC source and sink found widespread installation: the radar. The transistor – developed by the Bell Labs in 1947 – launched the success of microelectronics and all kinds of EMC sources and victims. One of the most dramatic interference sources was found in 1964, when the lights in Hawaii, 1445 km away, had been switched off due to a high-altitude nuclear test called Starfish Prime [1].
Cost-Effective Optimization Model for Transmission Line Outage Rate Control Due to Back-Flashover Phenomena
Published in Electric Power Components and Systems, 2018
Paulo M. De Oliveira-De Jesus, David Hernandez-Torres, Alberto J. Urdaneta
In addition, at the end of each counterpoise it is possible to install a ground rod (5/8”) with variable length (m). The test case considers NG=350 types of feasible electrodes and NI=3 types of insulation levels. Costs of material and installation (excavation and drilling activities) depend on the specific project. The cost of each electrode must be determined for the particular case of each support, depending on the material, transportation, excavation, drilling and installation costs.
Rydberg states of ZnAr complex
Published in Molecular Physics, 2022
Andrzej Kędziorski, J. Patrick Zobel, Marek Krośnicki, Jarosław Koperski
In the context of the convergence of the ab initio results with the basis set size, the additional ghost-atom basis functions located between the interacting atoms are often in use. Namely, these so-called midbond functions, in connection with the counterpoise method of the elimination of basis set superposition error (BSSE) [52], are known to speed up the convergence of the binding energy with respect to the basis set size [53–60] and it is especially pronounced in the case of theoretical description of the weak interatomic interactions, e.g. of the ground state of vdW complexes. Similar conclusions were derived from the symmetry-adapted perturbation theory (SAPT) [61–63], where the special emphasis is put on the convergence of the dispersion interaction energy with basis-set size. These comprehensive analyses have shown the ability to obtain very accurate results for weakly bound ground states with midbond functions. Although the midbond functions were also used for the calculations of the low excited states of vdW complexes, e.g. KrXe [64], benzene–Ar [65], p-difluorobenzene–Ar [66], fluorobenzene–Ar [67], H-BF [68], NO–Ne and NO–Ar [69], Ar–CS [70], Sr–H and Yb–H [71], ErYb [72], to the best of authors' knowledge there is no comprehensive analysis of the effect of inclusion of midbond functions on the description of the excited states. This work provides series of calculations performed with various basis sizes with and without midbond functions for the calculations of the excited valence and Rydberg states of ZnAr complex. This allows to show the considerable effect of use of the midbond functions especially for the description of the (inner) wells of the electronic excited states.