FM Frequency Research Articles

Fibromyalgia and Skin Disorders: A Systematic Review.

Background: Fibromyalgia is a complex multifaceted syndrome primarily characterised by chronic musculoskeletal pain, fatigue, and functional symptoms. Although FM is known to be associated with several comorbidities, the aim of this systematic review was to comprehensively examine the available evidence regarding the relationship between FM and dermatological manifestations. Methods: We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, and MedLine and Web of Science (WOS) databases were searched up to June 2023. After removing duplicate records, 21 articles were deemed eligible for inclusion in the qualitative synthesis. Results: Overall, the included studies revealed an increased frequency of FM among patients with cutaneous diseases, including psoriasis, chronic urticaria, contact allergy, acneiform disorders, hidradenitis suppurativa, and vitiligo. Additionally, the presence of comorbid FM may intensify skin conditions, which has a negative impact on quality of life and vice versa. Conclusions: Although the causal mechanisms of FM are still far from being understood, this systematic review suggests a relationship between FM and skin disorders. However, further research is encouraged in this area.

“Stay tuned!"

“Stay tuned!"

Survey of the Effect and Medical Application of Electromagnetic Radiation

Every electronic gadget that has become a part of daily life has had its electromagnetic radiation thoroughly examined. The maximum emission level and the minimum distance at which each device has an impact have been examined. Even in remote locations far from transmitters, the radio frequency field strength meter is an incredibly sensitive tool that can detect RF background with accuracy. The meter's display shows the true power density right away. The internal detection method of this meter produces a flat response across a very large frequency range, in contrast to other inexpensive field strength meters whose frequency response is dependent on the properties of an external antenna.Accuracy between 30 MHz and 2.4 GHz for FM, TV, and cell tower frequencies is +/-25%. Between 0.5 MHz and 3 GHz, the sensitivity is 50% (-3 dB) lower. At 5 GHz, sensitivity is 25%. In other words, when detecting microwaves at that high a frequency, you have to multiply the reading by 4. The sensitivity is roughly 10% at 10 GHz.).

Conversion of tones to soothing noise

When pure-tone sound signal of frequency fs interacts with a boundary whose acoustic property varies at a frequency of fm, part of the incident sound energy is scattered to the sum and difference frequencies, fs ± n fm, where n is any integer but n = 1 dominates. When the modulation frequency fm has a bandwidth, spanning from fm1 to fm2, the resulting scattered sound carries the same bandwidth of fm2-fm1. In this manner, pure tone is partly converted to broadband noise and will be less annoying to human ears. This talk first introduces the initial experimental evidence of such frequency scattering using a realistic design (see reference paper with doi:10.1038/ s42005-021-00721-1). Then the latest results of numerical study on the maximization of the energy scattering is presented. An attempt is also made to examine the question of what room mode or eigen frequencies will be when part of the room boundaries has a time-dependent wall properties. Note that the time-varying wall remains passive in the sense that the property variation is independent of the incident sound and there is no energy input required.

DeFLoc: Deep Learning Assisted Indoor Vehicle Localization Atop FM Fingerprint Map

Indoor vehicle localization is an underlying technology for realizing Autonomous Valet Parking (AVP), which demands high accuracy and reliability. However, existing localization technologies, such as GPS, WiFi, Bluetooth, suffer from either low availability or high cost, which are not practical in the real world. In order to put AVP into practice, We desperately need an efficient and reliable indoor vehicle localization technology. In this paper, we propose a <underline xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Dee</u> p learning and <underline xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">F</u> M fingerprint map based indoor vehicle <underline xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Loc</u> alization method, namely DeFLoc, which leverages FM signals to achieve accurate and practical indoor localization. In order to reduce the workload of the FM fingerprints collecting process, DeFLoc uses partially uniform sampling to decrease sample data volume and reconstructs the FM fingerprint map from collected incomplete fingerprints precisely using a dedicated deep Convolutional Neural Network (CNN). To alleviate the influence of signal distortions in some FM frequencies, we further design smooth layers in the neural network for improving the accuracy of map reconstruction. Moreover, we devise a continuous vehicle localization algorithm by considering the preferences of vehicle movements to assist us to calibrate localization. We implemented a prototype of DeFLoc and conducted extensive experiments both in simulation and practice. Evaluation results show that our proposed reconstruction model improves accuracy by 40% over conventional matrix completion methods even under the 60% data missing rate. With the precisely reconstructed fingerprint map, DeFLoc achieves over 90% localization accuracy, which indicates DeFLoc can realize accurate and practical indoor vehicle localization.

Shaping of Radio in Mexico in the Last Decade: 2010-2020

An analysis was made of the Mexican radio industry and the main groups that comprise it, describing the financial information that is available. The essay was elaborated following the deductive method, with a hermeneutic paradigm, according to the experience acquired in the radio industry. A linear regression was estimated from 2005 to 2020, showing a negative relationship of 98.9% between the percentage of households that have radio and those that have internet (the more households that use internet, the lower the proportion that use radio). Advertising in the national radio industry is falling sharply in recent years, in 2016 it absorbed 10.3% of total advertising spending in the country, reaching only 5% in 2020, declining to less than half of the share it had four years earlier. Grupo Radio Centro takes an average 15.4% of advertising from 2016 to 2020, while Televisa Radio takes 12% (before the sale of stations), both corporations take 27.5% in 2018 and 29.6% in 2019, adding six other radio groups (Fórmula, Imagen, Radio Mil, Radiorama, Stereo Rey and ACIR), they would at least have 41.1% of national radio revenues. The most important radio stations in the country have started to broadcast their content through websites, in which they transmit in real time the same programming they broadcast on their AM or FM frequency bands.

Root Endophytic Fungi Regulate Changes in Sugar and Medicinal Compositions of Polygonum cuspidatum.

Polygonum cuspidatum Sieb. et Zucc is an important industrial crop because it contains a large amount of medicinal secondary metabolites (such as polydatin, resveratrol, chrysophanol, and emodin). However, it is unclear whether root endophytic fungi increase the content of secondary metabolites in the plant. This study aimed to analyze the effects of Funneliformis mosseae (Fm) and Piriformospora indica (Pi) alone or in combination on plant growth, root morphology, thirteen sugars concentrations, and six secondary metabolites (physcion, chrysophanol, emodin, aloe-emodin, polydatin, and resveratrol) concentrations of P. cuspidatum. After 11 weeks of the fungal inoculation, the roots could be colonized by Fm and Pi single or in combination, along with the higher root colonization frequency of Fm > Pi > Fm + Pi in the descending order. In addition, Fm and Pi improved plant growth performance (plant height, stem diameter, leaf number, and shoot and root biomass) and root morphology (average diameter, maximum diameter, total length, area, and volume) to varying degrees, depending on fungal inoculations, in which Pi displayed a relatively better effect on plant growth. Single Fm and Pi inoculation significantly increased three disaccharides (sucrose, maltose, and trehalose) accumulation, while dual inoculum (Fm + Pi) only elevated sucrose concentrations. Most monosaccharides concentrations, such as D-arabinose, D-galactose, D-sorbitol, D-fructose, glucose, and L-rhamnose were not altered or inhibited by the endophytic fungi, except the increase in L-fucose and inositol. All fungal treatments significantly increased root chrysophanol and resveratrol concentrations, while decreased aloe-emodin concentrations. In addition, single Pi and dual Fm + Pi increased emodin concentrations, and single Fm and dual Fm + Pi elevated physcion and polydatin concentrations. It was concluded that Fm and Pi promoted the growth of P. cuspidatum, and the combination of Fm and Pi was more conducive to the production of some secondary metabolites than single inoculation.

A SEMANTIC ANALYSIS ON THE JAVANESE WORD “JAJAN” AS USED BY “SUARA AKBAR” RADIO LISTENER IN JEMBER

Indonesian is a very rich language originating from various regional languages throughout Indonesia which stretches from Sabang to Merauke. Of the 668 regional languages in Indonesia, there are several regional languages that are very influential for the development of the Indonesian language to date. Javanese is one of the languages that has the most influence on Indonesian vocabulary, in addition to Malay, Banjarese, Manadonese, Sasak, Sundanese, Bugis, and other regional languages. Javanese is the first language of the Javanese population living in Central Java Province, Special Region of Jogjakarta, East Java, Banten, Lampung, around Medan, transmigration areas in Indonesia, among others, parts of Riau, Jambi, Central Kalimantan, and several places in Indonesia. abroad, namely Suriname, the Netherlands, New Caledonia, and the West Coast of Johor The scope of this research covers the entire area of the city of Jember which is covered by the “Suara Akbar” radio wave on the 94.6 FM frequency. This study uses qualitative methods. The data used are sourced from or obtained through interviews, field notes, personal notes and other official documents.

A low-frequency blind survey of the low Earth orbit environment using non-coherent passive radar with the Murchison widefield array

AbstractWe have extended our previous work to use the Murchison widefield array (MWA) as a non-coherent passive radar system in the FM frequency band, using terrestrial FM transmitters to illuminate objects in low Earth orbit (LEO) and the MWA as the sensitive receiving element for the radar return. We have implemented a blind detection algorithm that searches for these reflected signals in difference images constructed using standard interferometric imaging techniques. From a large-scale survey using 20 h of archived MWA observations, we detect 74 unique objects over multiple passes, demonstrating the MWA to be a valuable addition to the global Space Domain Awareness network. We detected objects with ranges up to 977 km and as small as$0.03$${\rm m}^2$radar cross section. We found that 30 objects were either non-operational satellites or upper-stage rocket body debris. Additionally, we also detected FM reflections from Geminid meteors and aircraft flying over the MWA. Most of the detections of objects in LEO were found to lie within the parameter space predicted by previous feasibility studies, verifying the performance of the MWA for this application. We have also used our survey to characterise these reflected signals from LEO objects as a source of radio frequency interference (RFI) that corrupts astronomical observations. This has allowed us to undertake an initial analysis of the impact of this RFI on the MWA and the future square kilometer array (SKA). As part of this analysis, we show that the standard MWA RFI flagging strategy misses most of this RFI and that this should be a careful consideration for the SKA.

Radio station “Mayak” for 55 years: stages of development

This article is devoted to the 55th anniversary of the beginning of broadcasting radio “Mayak”. Due to a number of circumstances, among which the format of the radio station and the professional staff of its employees played a decisive role, “Mayak”, successfully working and having a large audience in the Soviet period, remained in the post-Soviet period, without losing its importance and weight. Having received in 2000 FM frequency, he was able to compete in the air and became an integral part of the new broadcasting system. The author identifies and analyzes the main innovations that have arisen in the air of this station, subsequently perceived by private commercial radio stations that have appeared in the post-Soviet space. The relevance of the article in determining the role of radio “Mayak” in the development and activities of domestic broadcasting, as well as in increasing the prestige and importance of the work of radio journalists. When writing the article, the author, who worked on the air of “Mayak” for more than ten years, who was both a witness and a participant in a number of innovative projects, used both conversations with veterans of the station and his personal experience, and the empirical method of research of the radio station “Mayak”.

Prediction of environmental effects in received signal strength in FM/TV station based on meteorological parameters using artificial neural network and data mining

In this paper, meteorological parameters, electric field strength and transmitters' output power measured during six months in a TV/FM station. There are 13 frequencies in FM and UHF frequency bands in pilot broadcast station. The analysis of results were carried out using data mining techniques. In addition, a prediction model on the basis of a Neural Network is identified. The electric field is affected by distance between the antenna and the receiver point, transmitters' output power and meteorological constituents of air pressure, temperature and humidity. The meteorological parameters and transmitters' power are used as inputs and the electric field is used as the output. After data acquisition, preprocessing is performed and the Neural Network of a multilayer perceptron model is applied. In addition, Multi Linear Regression is performed. In evaluation, the performance of the proposed techniques is based on the root mean square error (RMSE) property. The least MSE obtained for the proposed model based on Neural Network amounted to 0.198 while the least MSE of Regression was 0.280. The results showed that for a given input of the atmospheric parameters as well as the transmitter power, the intensity of electric field can be predicted as well as the determining the relationship between the atmospheric parameters, transmitters’ power and electric field strength. The statistical and correlation analysis used to assess the relation between each parameter and signal strength concluded that the temperature and wind direction have an inverted linear relationship with the signal level while the others have a direct linear relationship.

Measurement and evaluation of occupational exposure to electromagnetic field in the vicinity of FM/TV broadcast radiation

This paper involves the measurement and evaluation of electromagnetic field exposure levels at Kamarkouh FM/TV transmitter station at Qom province with multiple-frequency sources. Electromagnetic radiation levels were measured at 34 points for 6 min by Strength Meter Probe which is a broadband meter. The measured electromagnetic radiation levels were then compared to the International Commission of Non-Ionizing Radiation Protection standard. In addition, the theoretical electric field strength values at these same 34 points as above were estimated based on a free-space modeling calculation. The measurement results show that the maximum electromagnetic radiation level was 13.45 V/m, and this is far below the International Commission of Non-Ionizing Radiation Protection limits. The analysis of the comparison between calculated and measured electromagnetic radiation levels showed that there were other sources that contributed to increases in the electric field intensity. The source contributions to the total electric field strength were measured in a practical way. It means that by switching of the transmitters, the electric field strength measured in each state. The results showed that FM frequency band sources provided the highest contributions to the overall electromagnetic radiation level.

Political Spectrum: The Tumultuous Liberation of Wireless Technology, from Herbert Hoover to the Smartphone by Thomas Winslow Hazlett

Reviewed by: Political Spectrum: The Tumultuous Liberation of Wireless Technology, from Herbert Hoover to the Smartphone by Thomas Winslow Hazlett Jon Agar (bio) Political Spectrum: The Tumultuous Liberation of Wireless Technology, from Herbert Hoover to the Smartphone. By Thomas Winslow Hazlett. New Haven: Yale University Press, 2017. Pp. 416. Hardcover $35. The radio spectrum is an extraordinarily interesting subject for the historian of science and technology. On the one hand it is natural: radio waves have been filling the universe since the big bang. On the other hand it is artificial: the deliberate transmission and reception of radio waves for communication dates from Marconi in the late nineteenth century, and since then technologies to exploit the resource have become central to the modern world. As circuits became tunable and new applications proliferated, there has been increasing demand to use radio waves free from the interference of other users. From early in the twentieth century the response has been the parallel growth of a bureaucracy, at national and international levels, that has assigned frequencies and constructed the radio spectrum as a space to be sub-divided, occupied, and protected from trespass. [End Page 806] Hazlett, a professor of economics, believes that this bureaucratic management of the radio spectrum has been deeply inefficient. Political Spectrum is a messy, frustrating, occasionally entertaining, and insightful polemic. Readers will not find a balanced, straightforward account of the development of frequency assignment policies, nor an even-handed assessment of policy choices. What they will find is a story of free-market heroes and bureaucratic villains, and a plan for the future. Specifically, Hazlett calls for the auctioning of overlay rights, in other words allowing secondary licensees to make use of frequencies being left unused (or underused) by legacy licensees and granting them further rights, say to bargain with incumbents. Public agencies would be particular targets of this measure. Even public bodies that might be considered to have an overriding reason to be granted clear spectrum, such as first responders and the military, should, says Hazlett, be forced to purchase commercial wireless services and be subject to these processes of market liberalization. If such a policy was adopted, then the unleashing of market forces would produce a paradise of efficient and high quality wireless services. The problem is that Political Spectrum is poorly structured, jumping from period to period, appealing to personal anecdote when document-based reasoning is necessary, and reading evidence only in ways that support the overall argument. The actions of the Federal Radio Commission (FRC), later the Federal Communications Commission (FCC), are cases in point. This organization is the chief bureaucratic villain in Hazlett's eyes, and it can do no right. See, for example, the FRC's rejection of a plan to extend the range of AM frequencies in 1927 due to "the manifest inconvenience to the listening public which would result" (p. 48); Hazlett lambasts this action because it would force consumers to buy new receiver sets. Yet in the 1940s when the FCC did consider moving FM frequencies, which would have required early adopters to junk their receivers, Hazlett again criticizes it (p. 67). Damned if it does, damned if it doesn't, the government cannot get a break from Hazlett. Nevertheless, there are some useful contributions in Political Spectrum for the historian. Perhaps most interesting is the reassessment of the contribution of the economist Ronald Coase. An Englishman who moved to the United States in 1951, Coase brought fresh thinking to the "political economy of radio and television." Specifically, in the late 1950s, while at Stanford's Center for Advanced Study in the Behavioral Sciences, he built on the earlier arguments of Leo Herzel. Coase cogently argued that administrative control of the radio spectrum might be replaced by a "pricing mechanism." Coase submitted his paper to the Journal of Law and Economics, only to be told by the editors that he had made basic theoretical errors. Coase responded, saying that "even if my argument was an error, it was a very interesting error," and remarkably the editors conceded. Hazlett credits Coase as the discoverer of a "deeper truth" (p. 75), and as a prophet: [End Page 807] "Coase did not...

A Review on Investigation and Assessment of Path Loss Models in Urban and Rural Environment

This paper aims at providing a clear knowledge of Path Loss (PL) to the researcher. The important data have been extracted from the papers and mentioned in clear and precise manner. The limited studies were based on identification of PL due to FM frequency. Majority of studies based on identification of PL considering telephonic frequency as a source. In this paper the PL in urban and rural areas of different places due to various factors like buildings, trees, antenna height, forest etc. have been studied. The common parameters like frequency, model and location based studies were done. The studies were segregated based on various parameters in tabular format and they were compared based on frequency, location and best fit model in that table. Scatter chart was drawn in order to make the things clearer and more understandable. However, location specific PL models are required to investigate the RF propagation in identified terrain.

AULOS: Finmeccanica family of passive sensors

The name comes from an Ancient Greek wind instrument because AULOS is a passive family system developed by SELEX Sistemi Integrati (now Finmeccanica) that exploits electromagnetic energy already present in the environment such as FM frequency radio and DVB-T (digital video broadcast - terrestrial) emissions, and is completely environmentally friendly. The new green system is the result of many years of R&D, some undertaken in concert with the Terrestrial Armaments Department [1], [2], [3], [4]. It is a technologically advanced family of sensors developed entirely on the basis of a soft radar approach, involving signal sampling directly at carrier frequency using COTS (commercial off the shelf) devices for signal reception and digital processing. The resulting biband family offers great flexibility for potential use in a variety of operating conditions, along with enhanced target monitoring distance and position estimate performance.

High-purity 60GHz band millimeter-wave generation based on optically injected semiconductor laser under subharmonic microwave modulation.

Based on an optically injected semiconductor laser (OISL) operating at period-one (P1) nonlinear dynamical state, high-purity millimeter-wave generation at 60 GHz band is experimentally demonstrated via 1/4 and 1/9 subharmonic microwave modulation (the order of subharmonic is with respect to the frequency fc of the acquired 60 GHz band millimeter-wave but not the fundamental frequency f0 of P1 oscillation). Optical injection is firstly used to drive a semiconductor laser into P1 state. For the OISL operates at P1 state with a fundamental frequency f0 = 49.43 GHz, by introducing 1/4 subharmonic modulation with a modulation frequency of fm = 15.32 GHz, a 60 GHz band millimeter-wave with central frequency fc = 61.28 GHz ( = 4fm) is experimentally generated, whose linewidth is below 1.6 kHz and SSB phase noise at offset frequency 10 kHz is about -96 dBc/Hz. For fm is varied between 13.58 GHz and 16.49 GHz, fc can be tuned from 54.32 GHz to 65.96 GHz under matched modulation power Pm. Moreover, for the OISL operates at P1 state with f0 = 45.02 GHz, a higher order subharmonic modulation (1/9) is introduced into the OISL for obtaining high-purity 60 GHz band microwave signal. With (fm, Pm) = (7.23 GHz, 13.00 dBm), a microwave signal at 65.07 GHz ( = 9fm) with a linewidth below 1.6 kHz and a SSB phase noise less than -98 dBc/Hz is experimentally generated. Also, the central frequency fc can be tuned in a certain range through adjusting fm and selecting matched Pm.

Ambiguity Function Analysis and Processing for Passive Radar Based on CDR Digital Audio Broadcasting

China Digital Radio (CDR) broadcasting is a new standard of digital audio broadcasting of FM frequency (87108 MHz) based on our research and development efforts. It is compatible with the frequency spectrum in analog FM radio and satisfies the requirements for smooth transition from analog to digital signal in FM broadcasting in China. This paper focuses on the signal characteristics and processing methods of radio-based passive radar. The signal characteristics and ambiguity function of a passive radar illumination source are analyzed. The adverse effects on the target detection of the side peaks owing to cyclic prefix, the Doppler ambiguity strips because of signal synchronization, and the range of side peaks resulting from the signal discontinuous spectrum are then studied. Finally, methods for suppressing these side peaks are proposed and their effectiveness is verified by simulations.

Influence of electrodes on the effective electromechanical coupling coefficient distributions of high-overtone bulk acoustic resonator

In this paper, the influence of the electrodes on effective electromechanical coupling coefficient k2eff distribution of high-overtone bulk acoustic resonators (HBAR) is investigated using the four-layer thickness extension mode composite resonator model. The k2eff distributions and the spacing of the parallel resonance frequency (SPRF) distributions are calculated for HBARs with different electrode and substrate materials. The frequency of first peak fM in k2eff distribution curve is close to the frequency of first valley in SPRF distribution curve, which has the maximum deviation of about 20%. The fM ratio of Al0.1μm–ZnO0.6μm–Au0.1μm–Sapphire400μm to Au0.1μm–ZnO0.6μm–Al0.1μm–Sapphire400μm is 1.91 which indicated that the k2eff distribution of HBAR is affected significantly by different electrode materials. We discuss for the first time the influence of the acoustic impedance ratio of the electrodes to substrate to the k2eff distribution, which is independent on the thickness ratio of the electrodes to piezoelectric film. It is found that for the pure-hard and pure-soft substrate HBARs, the resonator frequency of piezoelectric sandwich structure can be used to estimate the resonator frequency fM of the first peak of k2eff curve, which has the maximum deviation of 7%. The fabricated HBAR(I) Al–ZnO–Al–Sapphire and HBAR(II) Al–ZnO–Au–Sapphire shows identical outlines of k2eff and SPRF curves with the simulations, which have fMs of about 2GHz and 3GHz. The k2t of ZnO films are extracted from the first peak of the k2eff curve. The ZnO film deposited on Al and Au electrodes have k2t of 0.0597 and 0.0615, respectively.

Design of Digital Broadcast Radio System Based on STM32

With the popularization of digital radio system, radio has also entered the digital age from the original analogue system. On the basis of the digital radio chip TEA5767 which used in the current widespread use of electronic products, this paper proposes and designs a digital broadcast receiving system based on STM32. The hardware circuit uses STM32F103VE as the main controller, with the configuration of digital radio chip TEA5767 and corresponding SD card storage module, LCD module, power module and so on; the software design adopts I2C bus to communicate and coordinate between the main controller and FM chip, achieving FM frequency and volume adjusting function. Meanwhile the μC/GUI is used to design the human-machine interactive interface. The digital broadcasting radio system has the advantages of small volume, multiple functions, low power consumption and easy to use.

Analysis of a Mn&amp;#x2013;Zn Ferrite Bundle EMI Suppressor Using Different Suppressing Principles and Configurations

A novel round cable electromagnetic interference (EMI) suppressor comprising a bundle of Mn-Zn ferrite tubes was realized using different principles of suppressing, such as direct suppressing, inverting/suppressing, transform/inverting suppressing, and transform/short circuited secondary suppressing. Different primary to secondary configurations were realized for each suppressing principle and characterized in the EMI frequency region. The results obtained for different bundle configurations were compared with known commercial round cable ferrite suppressors and the initial bundle configuration made of a half turn wire through the central ferrite tube of the bundle. The results obtained for different principles and configurations were correlated in order to optimize the electromagnetic coupling between primary and secondary circuits. The values such as maximums of impedance Zm, frequency of maximum impedance Fm and suppressing range Δf around Fm calculated on 0.707 Zm were defined as the main parameters for each configuration. Certain correlations were noticed between impedance Zm and frequency Fm changes. Finally, the realized configurations were considered as devices suitable for EMI suppressing applications.