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Copyright of Physics Essays is the property of Physics Essays Publication and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Water utilities in Japan face a number of challenges, including declining water demand due to a shrinking population, shrinking workforce, and aging water supply facilities. Widespread use of smart water meters is crucial for solving these problems. The widespread use of smart water meters is expected to bring many benefits such as reduced labor by automating meter reading, early identification of leaks, and visualization of pipeline data to strengthen the infrastructure of water services, business continuity, and customer service, as detailed data can be obtained using wireless communication. Demonstration tests are actively conducted in Japan; however, many problems have been reported with cast iron meter boxes blocking radio waves. To address the issue, a low-cost slit structure for cast iron meter boxes is investigated in this study. The results confirm that the L-shaped tapered slit array structure with a cavity, which can be fabricated in a cast iron integral structure, satisfies the design loads required for road installation. The proposed slit structure achieved gain characteristics from −3.32 to more than 9.54 dBi in the 800 to 920 MHz band. The gain characteristics of conventional cast iron meter boxes range from −15 to −20 dBi, and the gain has been significantly improved. Antennas with a gain of −2.0 to +1.5 dB (0.8 to 2.5 GHz) were used for the transmitter antenna, which was found to have a higher gain than the transmit antenna in the 800 to 880 MHz frequency band. In the 1.5 to 2.0 GHz band, a high peak gain of 4.25 dBi was achieved at 1660 MHz, with no null and the lowest gain confirmed that this is an improvement of more than 10 dBi over conventional products. [ABSTRACT FROM AUTHOR]

The accurate prediction of a signal's attenuation is essential for the development of reliable, modern, mobile radio-communication networks. In this study, the accuracies of four propagation models in diverse terrains and environments were analyzed using field measurements along a comprehensive test route. We evaluated the ability of the models—Egli, Okumura, Hata–Davidson, and Longley–Rice—to predict signal propagation in the Very-High-Frequency (VHF) and Ultra-High-Frequency (UHF) bands. Based on a meticulous comparison, we present valuable insights into the strengths and limitations of these models, enhancing coverage-prediction methodologies for evolving mobile radio networks. The Egli model, despite its simplicity, introduces significant inaccuracies due to its assumptions and a lack of consideration for the terrain. The Okumura model, which is widely used in urban areas, requires careful correction selection, while the Hata–Davidson model improves upon the former's weaknesses. The Longley–Rice model excels in flexibility and accuracy, especially in the VHF bands, using topographical data, though it can overestimate the attenuation in shadowed areas. The study concluded that no single model was universally accurate, as each model has its strengths and limitations. It highlights the need for informed model selection based on the terrain's characteristics and specific requirements. The results will be useful to network planners, helping them to design efficient, mobile communication networks with reliable coverage and optimal spectrum utilization. The Longley–Rice model emerged as particularly powerful, offering detailed predictions across diverse environments. [ABSTRACT FROM AUTHOR]

Radical pair kinetics is determined by the coherent and incoherent spin dynamics of spin pair and spin-selective chemical reactions. In a previous paper, reaction control and nuclear spin state selection by designed radiofrequency (RF) magnetic resonance was proposed. Here, we present two novel types of reaction control calculated by the local optimization method. One is anisotropic reaction control and the other is coherent path control. In both cases, the weighting parameters for the target states play an important role in the optimizing of the RF field. In the anisotropic control of radical pairs, the weighting parameters play an important role in the selection of the sub-ensemble. In coherent control, one can set the parameters for the intermediate states, and it is possible to specify the path to reach a final state by adjusting the weighting parameters. The global optimization of the weighting parameters for coherent control has been studied. These manifest calculations show the possibility of controlling the chemical reactions of radical pair intermediates in different ways. [ABSTRACT FROM AUTHOR]

The analysis of the field strength variability using the meteorological parameters (temperature, pressure and relative humidity) retrieved from the archive of National Aeronautical and Space administration (NASA) was conducted for 61 locations between 2016 and 2020 to check for the spatial and seasonal variation. The result shows a seasonal variation with higher field strength variability during the dry season and lower field strength variability during the wet season. The spatial variation shows a significant difference between stations in the drier locations up north and those in the coastal areas. This could be attributed to the moisture contents of the atmosphere. Further analysis of the Inter-Tropical Discontinuity (ITD) position during the study period has confirmed this assertion where we discovered the northward movement of the ITD brings along with it more moisture and consequently a weak field strength. The variation in the high grounds is not manifesting because of the fact that pressure has little influence on the field strength variability. A careful study of the pressure contour explains that. The mean field strength is found to be between 2:8 dB and 17:9 dB. This implies that the output of the receiving antenna should be less than 2:8 dB and can be as high as 17:9 dB. [ABSTRACT FROM AUTHOR]

The shielding of radio wave by steel-containing structures is desirable for electronics protection but undesirable for telecommunication signal reception. This work investigates the shielding behavior of steel structures consisting of members in various configurations, with the practical aim of determining how the configuration can be exploited to control the shielding. Differently oriented continuous steel reinforcement (stranded/unstranded wires in the unidirectional, crossply and planar coil configurations) are evaluated for electromagnetic interference (EMI) shielding at 600–2000 MHz, using unpolarized radiation. The absorption loss SEA dominates the reflection loss SER. The crossply configuration gives the highest SEA, SEA/thickness and SEA/SET (SET = total loss); the planar coil configuration gives the lowest values. The SEA, SEA/thickness and SEA/SET are moderately higher for the crossply configuration than the unidirectional configuration, because steel's electrical isotropy allows the 0° electric field to interact with the 90° wire. The SEA/SET is comparable for the stranded and unstranded wires. [ABSTRACT FROM AUTHOR]

Copyright of Al-Mustansiriyah Journal of Science is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper describes the design and performance of the search coil magnetometers (SCM), which are part of the Plasma Wave Investigation (PWI) instrument onboard the BepiColombo/Mio spacecraft (Mercury Magnetospheric Orbiter), which will measure the electric field, plasma waves and radio waves for the first time in Mercury's plasma environment. The SCM consists of two low-frequency orthogonal search coil sensors (LF-SC) measuring two components of the magnetic field (0.1 Hz – 20 kHz) in the spacecraft spin plane, and a dual-band search coil sensor (DB-SC) picking up the third component along the spin axis at both low-frequencies (LF: 0.1 Hz – 20 kHz) and high-frequencies (HF: 10 kHz – 640 kHz). The DB-SC and the two LF-SC sensors form a tri-axial configuration at the tip of a 4.6-m coilable mast (MAST-SC) extending from the spacecraft body, to minimize artificial magnetic field contamination emitted by the spacecraft electronics. After the successful launch of the spacecraft on 20 October 2018, an initial function check for the SCM was conducted. The nominal function and performance of the sensors and preamplifiers were confirmed, even with the MAST-SC being retracted and stowed in the spacecraft body, resulting in the detection of large interference signals likely from spacecraft electronics. The MAST-SC is scheduled for deployment after the Mercury orbit insertion of Mio in 2025, allowing the SCM to make the first higher frequency measurements of magnetic fluctuations in the Hermean magnetosphere and exosphere, and the local solar wind. These measurements will contribute to the investigation of fundamental problems in the Hermean plasma environment, including turbulence, magnetic reconnection, wave-particle interactions and particle acceleration. [ABSTRACT FROM AUTHOR]

The Plasma Wave Investigation (PWI) aboard the BepiColombo Mio (Mercury Magnetospheric Orbiter, MMO) will enable the first observations of electric fields, plasma waves, and radio waves in and around the Hermean magnetosphere and exosphere. The PWI has two sets of receivers (EWO with AM2P, SORBET) connected to two electric field sensors (MEFISTO and WPT) and two magnetic field sensors (SCM: LF-SC and DB-SC). After the launch on October 20, 2018, we began initial operations, confirmed that all receivers were functioning properly, and released the launch locks on the sensors. Those sensors are not deployed during the cruising phase, but the PWI is still capable performing magnetic field observations. After full deployment of all sensors following insertion into Mercury orbit, the PWI will start its measurements of the electric field from DC to 10 MHz using two dipole antennae with a 32-m tip-to-tip length in the spin plane and the magnetic field from 0.3 Hz to 20 kHz using a three-axis sensor and from 2.5 kHz to 640 kHz using a single-axis sensor at the tip of a 4.5-m solid boom extended from the spacecraft's side panel. Those receivers and sensors will provide (1) in-situ measurements of electron density and temperature that can be used to determine the structure and dynamics of the Hermean plasma environment; (2) in-situ measurements of the electron and ion scale waves that characterize the energetic processes governed by wave–particle interactions and non-MHD interactions; (3) information on radio waves, which can be used to remotely probe solar activity in the heliocentric sector facing Mercury, to study electromagnetic-energy transport to and from Mercury, and to obtain crustal information from reflected electromagnetic waves; and (4) information concerning dust impacts on the spacecraft body detected via potential disturbances. This paper summarizes the characteristics of the overall PWI, including its significance, its objectives, its expected performance specifications, and onboard and ground data processing. This paper also presents the detailed design of the receiver components installed in a unified chassis. The PWI in the cruise phase will observe magnetic-field turbulence during multiple flybys of Earth, Venus, and Mercury. After the Mercury-orbit insertion planned at the end of 2025, we will deploy all sensors and commence full operation while coordinating with all payloads onboard the Mio and MPO spacecraft. [ABSTRACT FROM AUTHOR]

The Sun was remarkably active during the first week of September 2017 producing numerous solar flares, solar radiation storms, and coronal mass ejections. This activity caused disruption to terrestrial high‐frequency (HF, 3–30 MHz) radio communication channels including observations with the Super Dual Auroral Radar Network (SuperDARN) HF radars. In this paper, we analyze the response of SuperDARN groundscatter observations and decreases in background sky noise level in response to multiple solar flares occurring in quick succession and co‐occurring with solar energetic protons and auroral activity. We estimate the attenuation in HF signal strength using an approach similar to riometry and find that the radars exhibit a nonlinear response to compound solar flare events. Additionally, we find that the three different space weather drivers have varying degrees of influence on the HF signal properties at different latitudes. Our study demonstrates that in addition to monitoring high‐latitude convection, SuperDARN observations can be used to study the spatiotemporal evolution of disruption to HF communication during extreme space weather conditions. Plain Language Summary: High‐frequency (HF, 3–30 MHz) communication system plays an essential role in emergency communications such as amateur radio, missile defense, and air traffic control. Most of these systems solely depend on HF communication that can travel beyond the horizon (over the horizon) without any relay or repeater network. This bending of the HF signal is feasible because of the presence of an electrically charged upper atmosphere, also known as ionosphere which can bend the HF signal back to the Earth. This electrically conducting upper atmosphere (ionosphere) can be influenced by the Sun and the outer space, commonly known as space weather. Extreme space weather events such as solar flares, radiation storms, and geomagnetic storms produced by the Sun can alter the state of the ionosphere and disrupt HF communication. During the first week of September 2017, the Sun produced numerous solar flares, radiation storms, and geomagnetic storms. This paper compares the impacts of isolated versus co‐occurring space weather disturbances on HF communications as observed by the Super Dual Auroral Radar Network HF radar network distributed across the North American sector. Key Points: SuperDARN HF radars observed a drop in signal strength in response to extreme space weather phenomena during September 2017Multiple solar flares occurring in quick succession produce nonlinear effects on radio wave absorptionCo‐occurring space weather phenomena have varying degrees of impact at different latitudes [ABSTRACT FROM AUTHOR]

This paper presents a new comprehensive space–time model of rainfall rate and its associated rainfield synthesizer called Grid Rain Attenuation Model (GRAM). A great deal of care is placed on explicitly including the rain/no rain condition so that the planning and simulation of high-frequency radio wave communication systems can be achieved with full consideration of rain intermittency effects. We also look in some details at the modification of the first- and second-order statistical descriptions of the rain precipitation rate upon the application of space and time integration to point rainfall rate. [ABSTRACT FROM AUTHOR]

In this paper, an antenna sensor for a radio-wave-type endoscope to detect a blood vessel in fatty tissue is proposed. The antenna sensor consists of one transmitting antenna and two receiving antennas. As the antenna element, microstrip antennas are used. The relationships between the antenna arrangement and the magnitude of the reflected wave from the blood vessel are discussed using a 2.5-times scale simulation model. In the simulation, it is confirmed that the blood vessel of 10 mm diameter can be detected at a distance of 10 mm from the top surface of the fatty tissue in the 2.5-times scale model using the proposed antenna sensor. [ABSTRACT FROM AUTHOR]

We compare the two approaches that have been used to measure the lowermost ionosphere, the measurement of the propagation of very low frequency (VLF) radio waves and the in situ sampling by sounding rockets. We focus on the altitude, latitude, and zenith angle variation of the electron density profiles inferred from these two observational techniques as compared with a theoretical photochemical model. Our results show that below 68–70 km, the VLF data and the model agree better with each other than with the sounding rocket profile. At the lowest altitudes, near 60 km, both the VLF data and the model show a greater electron density at higher latitudes, consistent with a cosmic ray flux that increases with latitude, whereas the limited rocket data show a maximum at the tropics. Above 68–70 km, the VLF data and the sounding rockets agree better and at tropical latitudes, the model fails to reproduce the observations. Specifically, the calculated electron density is lower than the data by up to a factor of 2. Possible reasons for the model deficit include underestimates of the solar Lyman alpha flux, the solar X‐ray flux and the mesospheric nitric oxide density. Once these three factors are mitigated, the model is in agreement with the observations between 60 and 80 km. Plain Language Summary: Over the past 50–60 years, there have been two approaches toward measuring the lowermost ionosphere (below 90 km), the D region. One is by modeling the propagation of VLF radio waves; the other is by in situ sampling via rockets. Until now, these techniques have not been rigorously intercompared. By comparing both with each other and with a theoretical photochemical model, we show how they are complementary. The very low frequency data are most accurate below 70 km, while the rocket data are more accurate above 70 km. The photochemical model can be made to agree with these data provided certain assumptions are made about the solar Lyman alpha flux, solar X‐rays, and mesospheric nitric oxide (NO). Key Points: We compare two independent techniques for measuring the D region ionosphereModeling VLF radio waves is most accurate below 70 km, in situ rockets are most accurate above 70 kmPhotochemical model can agree with observations, but there are uncertainties concerning neutral atmosphere and solar flux inputs [ABSTRACT FROM AUTHOR]

One-dimensional study of both electronic and electrical parameters of a silicon solar cell in the presence or not of an electric field, a magnetic field, or an electromagnetic field does not take into account the grain size and the grain boundary recombination velocity. A three-dimensional study, on the contrary, takes those factors into account. However, the three-dimensional study poses the problem of the attenuation of the wave in the grain of the polycrystalline solar cell as well as the issue of finding the expressions of its components. This study aimed to solve these issues by considering radio waves, which are becoming more and more present in our environment via telecommunication masts. We first obtained the expressions of both the electric field and magnetic field in a grain of a polycrystalline silicon solar cell by solving the dispersion equation. Then we investigated the evolution of the radio wave into the grain by analyzing the behavior of the exponential coefficient that appeared in the expressions of both the electric field and the magnetic field. The study has shown that the attenuation of the radio wave can be neglected through the polycrystalline silicon solar grain and by extension through the polycrystalline silicon solar cell. [ABSTRACT FROM AUTHOR]

Establishment of electromagnetic compatibility is important in use of electronic medical equipment in hospitals. To evaluate the electromagnetic environment, the electric field intensity induced by electromagnetic radiation in broadcasting spectra coming from outside the hospital was measured in a new hospital building before any patients visited the hospital and 6 months after the opening of the hospital. Various incoming radio waves were detected on the upper floors, with no significant difference in measured levels before and after opening of the hospital. There were no cellphone terminal signals before the hospital opened, but these signals were strongly detected at 6 months thereafter. Cellphone base stations signals were strongly detected on the upper floors, but there were no signals at most locations in the basement and in the center of the building on the lower floors. A maximum electrical intensity of 0.28 V/m from cellphone base stations (2.1 GHz) was detected at the south end of the 2nd floor before the hospital opened. This value is lower than the EMC marginal value for general electronic medical equipment specified in IEC 60601-1-2 (3 V/m). Therefore, electromagnetic interference with electronic medical equipment is unlikely in this situation. However, cellphone terminal signals were frequently detected in non-base station signal areas. This is a concern, and understanding signal strength from cellphone base stations at a hospital is important for promotion of greater safety. [ABSTRACT FROM AUTHOR]

Miniature devices development has been greatly complementing the technology developmental trend in telecommunication. This makes the new communication technology to sail smoothly into the society and creating unexpected market for both the telecommunication providers and embedded system manufactures. However power has been the major problem in the usage of some of these devices most especially in third world countries where power is epileptically supplied. This paper proposes a prototype system which wirelessly generates DC for charging and powering power-critical handheld and remotely located devices. The design captures 900MHz radio frequency signal with a dipole antenna, which is converted into DC and stores the power in the device's battery or use it to power it. The major aim of this paper is to provide a prototypical system which provides a cheap, constant and environmental friendly system for powering and charging power critical handheld and remote devices thereby prevents systems failure due to power loss. [ABSTRACT FROM AUTHOR]

Suture ligation is a simple method to curb the hemorrhoids. The present study was conducted to determine the usefulness of suture ligation in third-degree hemorrhoids and to compare it with author’s procedure of suture ligation coupled with hemorrhoidal ablation through radiowave. One hundred and twenty-four consecutive patients with grade III hemorrhoids requiring surgery were randomized into two groups. Half of them were treated by suture ligation, while the remaining patients underwent a radiowave ablation of hemorrhoids using a Ellman radiowave generator followed by suture ligation. A blinded observer evaluated postoperative pain scores, amount of analgesics consumed, and complications encountered. He also assessed recurrence of hemorrhoids after 1 year. The postoperative pain score was significantly higher in the suture ligation group (3.4 ± 0.2 vs. 2.2 ± 0.1, p < 0.005). The mean total analgesic dose and duration of pain control using analgesics were greater and longer for suture ligation group than radiowave group (29 ± 4 vs. 23 ± 3 tablets, and 15 ± 3 days vs. 12 ± 4 days, respectively; p < 0.001). Complications were seen more frequently in radiowave group (22% vs.18%). At 1 year follow-up, the recurrence of hemorrhoids was more significant with the suture ligation group (five patients vs. one patient, p < 0.05). Suture ligation of hemorrhoids is a simple, cost-effective, and a convenient modality in treating third-degree hemorrhoids. The efficacy and postoperative comfort is further enhanced if the hemorrhoids are ablated with radiowave prior to ligating them. [ABSTRACT FROM AUTHOR]

Results are presented on wideband radio propagation measurements and statistical modeling at 2.4 GHz and 5.8 GHz in real underground mine tunnels. This peculiar type of confined environment is characterized by very rough surfaces and a frequent absence of a line-of-sight between transmitting and receiving antennas. The resulting propagation characteristics differ from those frequently encountered in more typical indoor environments such as offices and corridors. Indeed, the rms delay spread shows little or no correlation with respect to transmitter-receiver distance and, in addition, no impulse response path arrival clustering effect is observed. However, the path amplitude distribution does tend to follow a Rice distribution in the line-of-sight case, and a Rayleigh distribution otherwise. [ABSTRACT FROM AUTHOR]

We investigate the potential of radio links such as employed by commercial cellular communication companies to monitor path-averaged rainfall. We present an analysis of data collected using two 38-GHz links during eight rainfall events over a 2-month period (October-November 2003) during mostly stratiform rainfall in the Netherlands. Comparisons between the time series of rainfall intensities estimated using the radio links and those measured by a nearby rain gauge and a composite of two C band weather radars show that the dynamics of the rain events is generally well captured by the radio links. This shows that such links are potentially a valuable addition to existing methods of rainfall estimation, provided the uncertainties related to the reference signal level, signal level resolution, wet antenna attenuation, and temporal sampling can be resolved. [ABSTRACT FROM AUTHOR]

Purpose - The purpose of this paper is to present a comprehensive overview of radio frequency identification (RFID) technology. The goal is to provide insights regarding the implementation and use of RFID by focusing on its advantages and its problems. Design/methodology/approach - The paper discusses, what RFID is, how its parts fit; what role management plays in its implementation, and where the pitfalls are. Findings - RFID is discussed as the latest technology to help manage the logistics and inventory problems faced by all companies. Not only has RFID been shown to provide benefits for the firm in its internal operations; its greatest contribution lies in its ability to improve information and materials flows throughout the entire supply chain. With RFID technology visibility in materials flow (from raw material to finished goods) among all supply chain members is improved and the accuracy of the information shared is greatly enhanced. Equally important is the role played by RFID in the development of more collaborative relations among supply chain members. Practical implications - For practicing managers the paper offers suggestions for improving the probability of a successful RFII) implementation. The paper discusses implications ranging from dealing with the physics of the aligning the equipment, to validity and reliability testing, to integrating a complete RFID system inside the firm, to developing the requisite metrics, mindset, and managerial systems to link all members of the supply chain. Originality/value - The paper combines practice and theory to demonstrate the potential benefits of RFID and provides insight into how to manage the problems that plague the rapid adoption of this new technology. [ABSTRACT FROM AUTHOR]

Copyright of Annals of Telecommunications is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annals of Telecommunications is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annals of Telecommunications is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annals of Telecommunications is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annals of Telecommunications is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Considering the different heights of transmitting and receiving antennas and the height variation of the superrefractive layer, the multipath depolarization statistical distributions due to clear air, the equiprobability linear relationship between cross-polarization (XPD) and copolarized attenuation (CPA) is studied based on computer simulation at a 7.6 GHz frequency. The computer simulation results show that the slope values of the equiprobability linear relationship between XPD and CPA vary in the interval from -1 to 0, which is different from earlier theoretical results. ©1999 John Wiley & Sons, Inc. Microwave Opt Technol Lett 23: 4–7, 1999. [ABSTRACT FROM AUTHOR]

Copyright of Annals of Telecommunications is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annals of Telecommunications is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annals of Telecommunications is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annals of Telecommunications is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annals of Telecommunications is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annals of Telecommunications is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annals of Telecommunications is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annals of Telecommunications is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annals of Telecommunications is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Les auteurs montrent à l'aide de données en provenance de trois liaisons d'essai que les fonctions de transfert pour une largeur de bande moyenne en situation de trajets multiples peuvent être représentées par des modèles à trois paramètres. De plus les paramètres des modèles obéissent aux mêmes lois statistiques sur les trois liaisons, fournissant ainsi un modèle statistique universel, dont ils montrent qu'il dépend de deux paramètres indépendants. On peut, lorsque ces deux paramètres statistiques sont connus, calculer à partir du modèle le temps de coupure de la liaison. La loi de distribution des niveaux à fréquence fixe permet une première estimation des paramètres statistiques d'un bond: on présente l'application de la méthode à deux liaisons particulières. It is shown, from data gathered on three different test links, that multipath transfer functions on a medium bandwidth can be modelled with three parameters. Moreover, the model parameters follow similar probability laws on the three links, thus leading to a universal statistical model. This statistical model depends on two independent parameters. When the two statistical parameters are known, the outage time of the link can be deduced from the model. A first estimation of these parameters can be inferred from the distribution law of the levels at fixed frequency. The application of the method to two particular cases is presented. [ABSTRACT FROM AUTHOR]

Copyright of Annals of Telecommunications is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

La représentation de la fonction de transfert d'un canal de transmission affecté de trajets multiples est analysée d'un point de vue général tout en gardant à l'esprit l'application aux faisceaux hertziens terrestres. On tire de cette représentation les fondements d'une modélisation en bande moyenne ainsi que des lois de variations de la sélectivité en fonction de la fréquence et de la longueur du bond. Frequency representation of multipath fading on line-of-sight microwave paths is revisited together with a general point of view and with the aim of giving sound foundations of medium bandwidth modelling. Moreover some typical laws of variation of the selectivity according to the frequency and the hop length are derived. [ABSTRACT FROM AUTHOR]

Copyright of Annals of Telecommunications is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We report on the measurements of radio frequency interference (RFI) at Mount Timau, Kupang, Indonesia, which is intended to host a future radio astronomy observatory. These measurements were taken twice in October 2020 and December 2020 to obtain the RFI environment, at frequencies between 70 and 7000 MHz. Due to the limitations of the measurement data, the results presented in this paper are based on peak detection rather than statistical analysis. Based on the measurement results, the frequency interval between 70–88 MHz and 120–150 MHz is relatively quiet, and the frequency range of 150–300 MHz is relatively clear. The frequency interval of 300 to 800 MHz is relatively quiet, except at the frequency of 600 MHz. The frequency range of 800–1400 MHz is also relatively quiet. The predominant terrestrial services in this band are at 840 MHz, with an amplitude around 32 dB, and 916 MHz, with an amplitude around 12 dB, and the global system for mobile (GSM) signals around 954 MHz have an amplitude around 20 dB above the noise floor. The frequency range of 1400–7000 MHz is also relatively quiet. In this band frequency, we can see RFI at 2145 and 2407 MHz, emitted by local Wi-Fi, and at 2683 MHz, with amplitudes of 18, 40 and 15 dB, respectively, from the noise level. We conclude that, for this period, the frequency band allocated for astronomy can possibly be used for radio telescope development. [ABSTRACT FROM AUTHOR]

In this letter, an integrated application of the prediction for radio wave propagation with the Geographic Information System (GIS) is presented and a real prediction system based on GIS is implemented. [ABSTRACT FROM AUTHOR]

In engineering we frequently make use of an oscilloscope to see the various forms of waves with which we work. If it is a sound wave, we would use a microphone to capture the wave. The microphone is known as a transducer, converting the acoustic energy into electrical energy. A photo-sensor acts as a transducer for a light wave and an antenna is able to retrieve a radio wave. To interpret the waves, of whichever kind, the waveform can be recorded and this is not a difficult task if the wave is displayable on the oscilloscope. Joseph Fourier (1768-1830) produced a theory that allowed us to analyze the waves that we record. His method can be likened to many of the tools that have been discussed. We have seen physical transformations to provide insights and this is a transformation of a mathematical kind. [ABSTRACT FROM PUBLISHER]

This article introduces an efficient analysis of indoor 4.5 GHz radio wave propagation by using a proposed three-dimensional (3-D) ray-tracing (RT) modeling and measurement. The attractive facilities of this frequency band have significantly increased in indoor radio wave communication systems. Radio propagation predictions by simulation method based on a site-specific model, such as RT is widely used to categorize radio wave channels. Although practical measurement provides accurate results, it still needs a considerable amount of resources. Hence, a computerized simulation tool would be a good solution to categorize the wireless channels. The simulation has been performed with an in-house developed software tool. Here, the 3-D shooting bouncing ray tracing (SBRT) and the proposed 3-D ray tracing simulation have been performed separately on a specific layout where the measurement is done. Several comparisons have been performed on the results of the measurement: the proposed method, and the existing SBRT method simulation with respect to received signal strength indication (RSSI) and path loss (PL). The comparative results demonstrate that the RSSI and the PL of proposed RT have better agreements with measurement than with those from the conventional SBRT outputs. [ABSTRACT FROM AUTHOR]

The Millimeter-Wave (mmW) technology is going to mitigate the global higher bandwidth carriers. It will dominate the future network system by the attractive advantages of the higher frequency band. Higher frequency offers a wider bandwidth spectrum. Therefore, its utilizations are rapidly increasing in the wireless communication system. In this paper, an indoor mmW propagation prediction is presented at 38 GHz based on measurements and the proposed Three-Dimensional (3-D) Ray Tracing (RT) simulation. Moreover, an additional simulation performed using 3-D Shooting Bouncing Ray (SBR) method is presented. Simulation using existing SBR and the proposed RT methods have been performed separately on a specific layout where the measurement campaign is conducted. The RT methods simulations results have been verified by comparing with actual measurement data. There is a significant agreement between the simulation and measurement with respect to path loss and received signal strength indication. The analysis result shows that the proposed RT method output has better agreement with measurement output when compared to the SBR method. According to the result of the propagation prediction analysis, it can be stated that the proposed method's ray tracing is capable of predicting the mmW propagation based on a raw sketch of the real environment. [ABSTRACT FROM AUTHOR]