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Satellite based communication either in GEO or LEO based system are prominently employed for voice, video, data communication. Demand of more traffic necessitates the data rate of satellite to be enhanced which can be implemented by the proper choice of modulation scheme. Presently ground systems are also wireless based which include direct broadcast satellite (DBS),television service, wireless local area networks (WLANs), global positioning satellite (GPS), radio-frequency identification systems which is either point-to-point or point-to-multipoint. Modern day communication systems are digital; based rather than analog to have better noise immunity. Further with the limited spectrum availability the choice of modulation scheme plays an important role for faithful transmission of the signal. The digital communication can be categorized as Amplitude Shift Keying (ASK), Frequency Shift Keying (FSK), Phase Shift Keying (PSK) whereas for higher bit data rate Phase Shift Keying (PSK) such as BPSK, QPSK and OQPSK are employed. This article overview of various modulation schemes which are employed in satellite communication apart from its selection criteria along with the concept of bit error rate. [ABSTRACT FROM AUTHOR]

In this study, the total electromagnetic dose, i.e., the combined dose from fixed antennas and mobile devices, was estimated for a number of hypothetical network topologies for implementation in Switzerland to support the deployment of fifth generation (5G) mobile communication systems while maintaining exposure guidelines for public safety. In this study, we consider frequency range 1 (FR1) and various user scenarios. The estimated dose in hypothetical 5G networks was extrapolated from measurements in one of the Swiss 4G networks and by means of Monte Carlo analysis. The results show that the peak dose is always dominated by an individual's mobile phone and, in the case of non-users, by the bystanders' mobile phones. The reduction in cell size and the separation of indoor and outdoor coverage can substantially reduce the total dose by >10 dB. The introduction of higher frequencies in 5G mobile networks, e.g., 3.6 GHz, reduces the specific absorption rate (SAR) in the entire brain by an average of −8 dB, while the SAR in the superficial tissues of the brain remains locally constant, i.e., within ±3 dB. Data from real networks with multiple-input multiple-output (MIMO) were not available; the effect of adaptive beam-forming antennas on the dose will need to be quantitatively revisited when 5G networks are fully established. [ABSTRACT FROM AUTHOR]

Wearable sensors promise to transform human understanding of body state. However, despite many wearable sensor modalities that exist, few demonstrate the raw capabilities required for many emerging healthcare applications—passivity (and microelectronics‐free), wireless readout, long‐term operation, and specificity. Hydrogel‐interlayer radio‐frequency resonators are demonstrated as a versatile platform for passive and wireless biosensing. Fabricated using a simple vinyl cutter, the base resonator is composed of unanchored, broad‐side coupled coils interceded by multifunctional hydrogels—such resonators are tuned to be sensitive to specific analytical or physical signals by modifying hydrogel composition. These resonators are transformed into near‐field communication (NFC) sensor circuits through the simple attachment of an LED. These enable direct quantification of sensor state by cellphone and eye with no specialized electronics required. Resonator arrays are finally fused with silicone to form soft, wireless sensor skins that enable co‐readout of analytical to physical signals while molded to human subjects. Such low‐cost, accessible platforms can integrate with environments in transformative ways, enabling new applications in wireless sensing. [ABSTRACT FROM AUTHOR]

A comparative study of capacitively coupled radio frequency discharges was conducted using 2-D particle-in-cell simulation (PIC) and 2-D fluid plasma simulation. The selected scenario was a planar discharge with a 3-cm gap operated in helium, at a gas pressure of 400 Pa, with a driving voltage between 120 and 400 V at 3.2 MHz. The solvers were adapted to a 1-D problem by using periodic boundary conditions perpendicular to the gap, and the models included ion impact-induced secondary electron emission from the electrodes. A good agreement was obtained between the results of both solvers, with less than 23% deviation in the peak plasma density. For the studied range of secondary emission coefficients, $0.08 < \gamma _{\mathrm {se}} < 0.378$ , it was found that a common transition point between “alpha” and “gamma” modes occurs at $V_{\mathbf {rf}} \sim 250$ V. Since the simulation results were shown to be less sensitive to the secondary emission coefficient below this transition voltage, these results can serve as a standard benchmark for plasma codes. [ABSTRACT FROM AUTHOR]

The rf R&D program for high-gradient, low frequency cavities to be used in muon cooling systems is underway in the Fermilab MUCOOL Test Area. Cavities at 805 and 201 MHz are used for tests of conditioning techniques, surface modification and breakdown studies. This work has the Muon Ionization Cooling Experiment (MICE) as its immediate goal and efficient muon cooling systems for neutrino sources and muon colliders as the long term goal. We study breakdown and dark current production under a variety of conditions.

This paper proposes a Tunnel FET (TFET)-based power management circuit (PMC) for ultra-low power RF energy harvesting applications. In contrast with conventional thermionic devices, the band-to-band tunneling mechanism of TFETs allows a better switching performance at sub-0.2 V operation. As a result, improved efficiencies in RF-powered circuits are achieved, thanks to increased rectification performance at low power levels and to the reduced energy required for a proper PMC operation. It is shown by simulations that heterojunction TFET devices designed with III-V materials can improve the rectification process at received power levels below -20 dBm (915 MHz) when compared to the application of homojunction III-V TFETs and Si FinFETs. For an available power of -25 dBm, the proposed converter is able to deliver 1.1 μW of average power (with 0.5 V) to the output load with a boost efficiency of 86%.

Plasma-based surface modification is recognized as an effective way to activate biomaterial surfaces, and modulate their interactions with cells, extracellular matrix proteins, and other materials. However, treatment of a luminal surface of a tubular scaffold remains non-trivial to perform in small diameter tubes. Polyvinyl alcohol (PVA) hydrogel, which has been widely used for medical applications, lacks functional groups to mediate cell attachment. This poses an issue for vascular applications, as endothelialization in a vascular graft lumen is crucial to maintain long term graft patency. In this study, a Radio Frequency Glow Discharges (RFGD) treatment in the presence of NH3 was used to modify the luminal surface of 3-mm diameter dehydrated PVA vascular grafts. The grafted nitrogen containing functional groups demonstrated stability, and in vitro endothelialization was successfully maintained for at least 30 days. The plasma-modified PVA displayed a higher percentage of carbonyl groups over the untreated PVA control. Plasma treatment on PVA patterned with microtopographies was also studied, with only the concave microlenses topography demonstrating a significant increase in platelet adhesion. Thus, the study has shown the possibility of modifying a small diameter hydrogel tubular scaffold with the RFGD plasma treatment technique and demonstrated stability in ambient storage conditions for up to 30 days.

Most waste solvent treatment methods involve combustion; however, such methods emit carbon dioxide and are also problematic relative to energy costs. As well as reducing carbon dioxide generate, in-liquid plasma has been used to generate valuable substances and hydrogen energy from the waste solvent. As a waste solve treatment model, decomposition of acetone using 27.12 MHz in-liquid plasma was performed at atmospheric pressure. The produced gases were H 2 , CO, CH 4 , C 2 H 2 , C 2 H 4 , C 2 H 6 , and CO 2, where proportion of CO 2 was less than 0.25%. Two types of carbons with different properties were obtained as byproducts during the acetone decomposition. These carbons analyzed using elemental analysis and Raman spectroscopy. The analysis results revealed that the crystallinity of the carbons different significantly. Undesirable organic matter, such as benzene, was also produced during acetone decomposition. The acetone decomposition efficiency at 407 W discharge power was 0.9 μmol J−1. • As a waste solve treatment model, decomposition of acetone using in-liquid plasma was performed. • Solidification of carbon can suppress the amount of CO 2 produced. • Two types of carbons with different crystallinity were obtained as byproducts. • The decomposition efficiency of acetone increased with the increase of discharge power. • The maximum hydrogen production efficiency was approximately 1.0 μmolJ−1. [ABSTRACT FROM AUTHOR]

A multi-band body-worn distributed exposure meter (BWDM) is designed and calibrated for diffuse fields in a reverberation chamber (RC) for personal exposure assessment in indoor environments. The BWDM uses 22 nodes distributed over the torso and measures the incident power density ($S_{\mathrm{ inc}}$) on body for 11 telecommunication bands in the frequency range of 790–5513 MHz. In order to calibrate the measurement device in diffuse fields, a protocol is proposed for on-body calibration of the BWDM. This protocol is applicable to wearable personal exposure meters in general. The BWDM and the proposed calibration protocol are validated in five indoor locations and five frequency bands (the downlink bands at 800, 900, 1800, and 2100 MHz as well as Wi-Fi 2 GHz) using a tri-axial broadband antenna and a spectrum analyzer (SA). The calibration shows that the BWDM has a relatively low measurement uncertainty with a 68% confidence interval on its antenna apertures, in the range 3.4–5.5 dB. A maximum difference of 0.9 dB is obtained for the total exposure in the test areas between the measurements of the BWDM and SA, which is an excellent agreement. [ABSTRACT FROM AUTHOR]

Muon spectroscopy offers a uniquely sensitive method for exploring many mechanisms in chemistry and chemical physics through the study of muonium, a probe species formed during muon implantation that is chemically equivalent to hydrogen. Next generation experiments in the field of muonium chemistry will require reliable liquid handling systems, in-situ experimental capabilities and access to advanced methods such as Radio-Frequency (RF) muon spin resonance spectroscopy. This paper discusses the development and commissioning of systems for sample handling, describing details of two liquid panels suitable for deoxygenation and transfer of liquid samples, the development of a centre stick for an existing 4He flow cryostat suitable for RF muon chemistry experiments, a dedicated muon chemistry insert specifically optimized for RF liquid phase chemistry experiments, and a birdcage RF cavity optimized for high frequency measurements and with a geometry well-suited for beamline experiments that exploit the chemistry insert. Example data is presented, demonstrating the application of these various pieces of equipment. [ABSTRACT FROM AUTHOR]

The electrical properties of soil at low radio-frequencies are important for engineering applications. In this work the effects of excitation frequency (42 Hz-1 MHz) as well as soil characteristics and conditions on the electrical properties of soil are experimentally investigated using remolded soil samples. Several sandy soils were tested with variable water content (dry up to saturation) using guarded two-electrode arrangements. A method is proposed based on the Nyquist plot to estimate the critical frequency above which measurements of the electrical properties of wet soil are free from electrode polarization effects. The latter result in extremely high real permittivity values, which do not correspond to the response of soil. The critical frequency is higher for smaller grain size and higher water content and varies according to a power law with soil power-frequency conductivity. The real and (effective) imaginary relative permittivity decrease with increasing frequency whereas the effective conductivity increases; this is attributed to the distributed relaxation of the interfacial polarization mechanism associated with the particulate nature of soil. The values of soil electrical properties increase with increasing water content and decreasing grain size (increasing specific surface) as a consequence of enhanced polarization and conduction phenomena. The effective imaginary permittivity varies with frequency according to a power law with an exponent approximately −1; the multiplier coefficient of this law expresses losses and has been formulated as a function of the degree of saturation and soil specific surface. [ABSTRACT FROM AUTHOR]

Abstract We present a particle-level model for calculating the radio scatter of incident RF radiation from the plasma formed in the wake of a particle shower. We incorporate this model into a software module ("RadioScatter"), which calculates the collective scattered signal using the individual particle equations of motion, accounting for plasma effects, transmitter and receiver geometries, refraction at boundaries, and antenna gain patterns. We find appreciable collective scattering amplitudes with coherent phase for a range of geometries, with high geometric and volumetric acceptance. Details of the calculation are discussed, as well as the implementation of RadioScatter into GEANT4. A laboratory test of our model, currently scheduled at SLAC in 2018, with the goal of measuring the time-dependent characteristics of the reflecting plasma, is also described. Prospects for a future in-ice, high-energy neutrino detector, along with comparison to current detection strategies, are presented. [ABSTRACT FROM AUTHOR]

Objectives: To assess the safety and effectiveness of in‐office bipolar radiofrequency treatment of nasal valve obstruction Study Design: Prospective, nonrandomized, multicenter case series Methods: Adult patients with a Nasal Obstruction Symptom Evaluation scale (NOSE) score ≥60 were selected. Patients were clinically diagnosed with dynamic or static internal nasal valve obstruction as primary or significant contributor to obstruction and were required to have a positive response to nasal mechanical dilators or lateralization maneuvers. Bilateral radio‐frequency treatment was applied intranasally using a novel device, under local anesthesia in a single session. Safety and tolerance were assessed by event reporting, inspection, and Visual Analogue Scale (VAS) for pain. Efficacy was determined using the NOSE score and patient‐reported satisfaction survey at 26 weeks. Results: Fifty patients were treated. No device or procedure‐related serious adverse events occurred. Soreness, edema, and crusting resolved by 1 month. The mean baseline NOSE score was 79.9 (SD 10.8, range 60–100), and all had severe or extreme obstruction. At 26 weeks, mean NOSE score was 69% lower at 24.7 (P <.0001) with 95% two‐sided confidence intervals 48.5 to 61.1 for decrease. The decrease in NOSE score did not differ significantly between patients who did or did not have prior nasal surgery. Patient satisfaction mean by survey was 8.2 of 10. Conclusion: In office treatment of internal nasal valve obstruction using a bipolar radiofrequency device is safe and well‐tolerated. Nasal obstruction, as assessed using the NOSE questionnaire at 26 weeks, was markedly improved with high patient satisfaction. Level of Evidence: 2b, prospective cohort [ABSTRACT FROM AUTHOR]

Abstract Owing to their small interaction cross-section, neutrinos are unparalleled astronomical tracers. Ultra-high energy (UHE; E > 10 PeV) neutrinos probe the most distant, most explosive sources in the Universe, often obscured to optical telescopes. Radio-frequency (RF) detection of Askaryan radiation in cold polar ice is currently regarded as the best experimental measurement technique for UHE neutrinos, provided the RF properties of the ice target can be well-understood. To that end, the Askaryan Radio Array (ARA) experiment at the South Pole has used long-baseline RF propagation to extract information on the index-of-refraction (n = ϵ r ) in South Polar ice. Owing to the increasing ice density over the upper 150–200 m, rays are measured along two, nearly parallel paths, one of which refracts through an inflection point, with differences in both arrival time and arrival angle that can be used to constrain the neutrino properties. We also observe (first) indications for RF ice birefringence for signals propagating along predominantly horizontal trajectories, corresponding to an asymmetry of order 0.1% between the ordinary and extra-ordinary birefringent axes, numerically compatible with previous measurements of birefringent asymmetries for vertically-propagating radio-frequency signals at South Pole. Qualitatively, these effects offer the possibility of redundantly measuring the range from receiver to a neutrino interaction in Antarctic ice, if receiver antennas are deployed at shallow (z ∼ −25 m) depths. Such range information is essential in determining both the neutrino energy, as well as the incident neutrino direction. [ABSTRACT FROM AUTHOR]

Abstract AlGaN/GaN/Si high electron mobility transistors (HEMTs) developed by molecular beam epitaxy (MBE) are studied with several methods for characterization, the most utilized are direct-current and radio-frequency measurements, to see power and microwave performance of components. The increase in these parameters is not based just with on improvement technological for example, decrease of length gate (Lg) and passivation. For sure, another very important point is to reduce the thickness of barrier while keeping the reduction in the length of gate, in order to reduce the transit time (τ), and consequently access to highest cut-off frequency (F T). For this situation, it's appears a harmful phenomenon of type "punch-through", because of the weak confinement of electrons in the channel. In this paper, the main objective is to show how to reduce this effect. [ABSTRACT FROM AUTHOR]

AlGaN/GaN high electron mobility transistors (HEMTs) on Silicon substrates grown by molecular beam epitaxy have been investigated using small-signal microwave measurements, to see performance Radio-frequency of components. Passivation of HEMT devices SiO2/SiN a different pretreatment is used to reduce the effects of trapping and consequently has a large effect on these radio-frequency parameters. We used cold-FET and hot FET technique to extract the intrinsic and extrinsic parameters in order to show the effect passivation of parasitic elements; the parasitic capacitances, resistances and inductances. From this point we discover the extent of their impact on power and microwave performance. [ABSTRACT FROM AUTHOR]

BACKGROUND Cordyceps militaris is a medicine and food dual‐purpose mushroom extensively cultivated and consumed in East and Southeast Asia for centuries. However, it has an extremely short shelf life of 3–4 days at room temperature. C. militaris was pasteurized for 10, 20, and 30 min by radio‐frequency (RF) at an electrode gap of 20 mm. The effect of RF heating on the microbial load, color, texture, and flavor attributes of C. militaris was evaluated and compared with those sterilized by conventional high‐pressure steam. RESULTS: RF heating contributed to good heating uniformity, uniform temperature distribution, and significant decrease in total microbial load. C. militaris heated by RF exhibited unnoticeable total color difference compared with unpasteurized ones, while those sterilized by high‐pressure steam presented undesired and unacceptable browning. Insignificant differences in hardness and chewiness were observed after RF heating. Improvements in mushroom‐like flavor occurred after 10 and 20 min of RF heating. CONCLUSION: This study suggests that RF heating for pasteurization of edible mushrooms has promising prospects. Evaluation of RF heating on the taste and nutritional characteristics of edible mushrooms is needed in future work. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In the past decade, graphene has been widely researched to improve or overcome the performance of conventional radio-frequency (RF) nanodevices and circuits. In recent years, novel RF bio and gas sensors based on graphene and its derivatives, graphene oxide (GO) and reduced graphene oxide (rGO), have emerged as new RF sensing platforms using a wireless remote system. Although the sensing schemes are still immature, this review focuses on the recent trends and advances of graphene and GO (rGO)-based RF bio and gas sensors for a real-time and continuous wireless health care system.

This review paper focuses on radio-frequency (RF) biosensors for real-time and continuous glucose sensing reported in the literature, including our recent research. Diverse versions of glucose biosensors based on RF devices and circuits are briefly introduced, and their performances are compared. In addition, the limitations of the developed RF glucose biosensors are discussed. Finally, we present perspectives on state-of-art RF biosensing chips for point-of-care diagnosis and describe their future challenges.

In this study, the total electromagnetic dose, i.e., the combined dose from fixed antennas and mobile devices, was estimated for a number of hypothetical network topologies for implementation in Switzerland to support the deployment of fifth generation (5G) mobile communication systems while maintaining exposure guidelines for public safety. In this study, we consider frequency range 1 (FR1) and various user scenarios. The estimated dose in hypothetical 5G networks was extrapolated from measurements in one of the Swiss 4G networks and by means of Monte Carlo analysis. The results show that the peak dose is always dominated by an individual’s mobile phone and, in the case of non-users, by the bystanders’ mobile phones. The reduction in cell size and the separation of indoor and outdoor coverage can substantially reduce the total dose by >10 dB. The introduction of higher frequencies in 5G mobile networks, e.g., 3.6 GHz, reduces the specific absorption rate (SAR) in the entire brain by an average of −8 dB, while the SAR in the superficial tissues of the brain remains locally constant, i.e., within ±3 dB. Data from real networks with multiple-input multiple-output (MIMO) were not available; the effect of adaptive beam-forming antennas on the dose will need to be quantitatively revisited when 5G networks are fully established.

Treatments in the field of aesthetic medicine are gaining more and more. Especially the minimally invasive therapies. The treatment of submental fat and skin laxity is becoming increasingly interesting, as it also borders the face. A range of mono- and bipolar radiofrequency devices are being used as new treatments for skin rejuvenation and tightening. We report here a case and show that subdermal induction heating technology also known as endodermal radiofrequency is one of the most effective applications of this treatment method. Possible contraindications should be considered and written down. The application of endodermal radiofrequency therapy (S.I.H.Technology) requires a comprehensive training, because to the current knowledge, the experience of the physician in the use of high-frequency devices is most important for a successful outcome. [ABSTRACT FROM AUTHOR]

Objective(s): Nowadays, the electromagnetic field-emitting devices are used routinely in our lives. Controversial reports exist concerning the effects of mobile radiofrequency (RF) on different parts of the body, especially stress hormones. The main goal of the present work was to study the long-term effects of mobile RF900 MHz exposure with special focus on the adrenal gland pathophysiology and function. Materials and Methods: Adult male Wistar rats were exposed to mobile RF 6 hr daily for 4-8 weeks. Intact and switched-off exposed animals were considered as controls. Plasma ACTH and cortisol levels were measured by the ELISA method. At the end of the experiment, a histological study was done on adrenal gland and brain tissues by hematoxylin and eosin staining. The thickness of the fasciculate layer of the adrenal gland, and its cell count and perimeter were measured using the Fiji software. Results: Enhanced plasma ACTH and cortisol levels were found after prolonged exposure to mobile RF. The fasciculata layer of adrenal cortex eventually thickened following mobile RF radiation. While the number of cells in zona fasciculata remained constant, the cell size and perimeter increased during RF exposure. Finally, we found that vacuolization in brain tissue and the number and size of vacuoles considerably increased during two months of RF exposure. Conclusion: Cell phone RF exposure induced significant hormonal and structural changes in adrenal gland and brain tissues. Therefore, the public should be aware and limit their exposure as much as possible. [ABSTRACT FROM AUTHOR]

The ITER Ion Cyclotron Resonance Heating (ICRH) system is designed to couple to the plasma 20 MW of RF power from two antennas in the 40–55 MHz frequency range during long pulses of up to 3600 s and under various plasma conditions with Edge Localized Modes. Radio-Frequency (RF) contacts are integrated within the ITER ICRH launcher in order to ensure the RF current continuity and ease the mechanical assembly by allowing the free thermal expansion of the Removable Vacuum Transmission Line coaxial conductors during RF operations or during 250 °C baking phases. A material study has been carried out to determine which materials and associated coatings are relevant for RF contacts application in ITER. In parallel, RF tests have been performed with a new prototype of Multi-Contact ® LA-CUT/0,25/0 contacts made of silver-coated CuCrZr louvers. During these tests on a RF vacuum resonator, currents between 1.2 kA and 1.3 kA peak have been reached a few tens of times in steady-state conditions without any visible damage on the louvers. A final 62 MHz pulse ending in a 300 s flat top at 1.9 kA resulted in severe damage to the contact. In addition, a test bed which performs sliding test cycles has been built in order to reproduce the wear of the contact prototype after 30 000 sliding cycles on a 3 mm stroke at 175 °C under vacuum. The silver coating of the louvers is removed after approximately a hundred cycles whilst, to the contrary, damage to the CuCrZr louvers is relatively low. [ABSTRACT FROM AUTHOR]

We have fabricated top-gated ambipolar field-effect transistors (FETs) based on solution-derived carbon nanotube (CNT) network films, and then constructed inverters and ring oscillators (ROs) that can work under supply voltages as low as 0.2 V owing to the high uniformity of the devices. Significant improvements were achieved in the performance of these CNT-based ambipolar FETs and CMOS-like circuits by scaling down the gate length of the CNT FETs and optimizing the device structure and RO layout. In particular, the optimized five-stage RO is shown to present a record high oscillation frequency of up to 17.4 MHz with a propagation time of 5.6 ns at a 12-V working voltage. The CNT film-based ROs were used as carrier-wave generators in radio-frequency systems to demonstrate a complete signal transmission process. These results suggest that CNT thin film-based FETs and integrated circuits may soon find their way to radio-frequency applications with a frequency band of 13.56 MHz. [ABSTRACT FROM AUTHOR]

This article presents an optimization technique aiming to improve gain and noise performances simultaneously, through the design of a cost-effective low noise amplifier (LNA) in a mixed-signal CMOS process without an RF triple-well option. To alleviate the inherent body-effect within a twin-well MOS transistor, we applied a transmission-line based source degeneration inductor Ls instead of a conventional spiral in the RF amplifier. In our design, without additional DC-power payment, the gain and noise figures ( NF50) improved by 26% and 7.1%, respectively, when compared to the conventional spiral. The proposed LNA was implemented in a 0.18 µm 1-poly 6-metal mixed-signal CMOS process, and achieved a 13.1 dB gain and 2.72 dB noise figure while dissipating 8.76 mA from a 1.4 V supply. [ABSTRACT FROM AUTHOR]

Conventional thawing processes adopted by food industry are characterized by longer operation times and food quality losses. Recently, batch and continuous radio-frequency (RF) assisted thawing were proposed as alternative and faster process, but their economic feasibility at industrial level is far to be assessed. Undoubtedly, longer penetration depth and ability to generate volumetric heat enable RF assisted heating a very promising technology to apply at industrial scale. On the other hand, most of the RF systems in operation are built following heuristic criteria, more than being designed and tailored on specific products or processes: this has limited the development of RF based system for food thawing as well as the proposal of simple but effective control systems. The literature has contributed with a number of theoretical and modeling based works for RF processes, but design-based studies in general are limited. Therefore, the objective of this study was to present a strategy for virtual design of a continuous RF thawing process. For this purpose, a previously developed and experimentally validated mathematical model was modified to take into account the movement of food product through a continuous RF system, the movement of RF electrode and subsequent effects of temperature and electric field changes. Power uniformity index (PUI) for various proposed configurations was analyzed, and possible scenarios were suggested for an industrial scale process. With this concept, this study was assumed to be significant for design and optimization of industrial RF and RF thawing processes. [ABSTRACT FROM AUTHOR]

ABSTRACT In this letter, we evaluate the noise figure (NF) improvement that results from controlling the parasitic gate resistance of a radio-frequency (RF) low noise amplifier (LNA). By optimizing the number of gate contacts and wiring modifications in our fabricated device, the customized layout exhibited an approximately 25% reduction in the gate electrode resistance (Relect) when compared to a reference device provided by the foundry. The fabricated LNA, which used a customized layout in a 0.18 μm standard CMOS process, improved the NF by almost 6% without affecting the Si area and DC power consumption, and exhibited a NF of 2.57 dB, gain of 11.6 dB, DC power dissipation of 4.0 mW, and return loss at both the input and output of more than 10 dB. © 2017 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:1405-1407, 2017 [ABSTRACT FROM AUTHOR]

Electronic monitoring (EM) has been introduced in over 30 countries around the world. In most English-speaking countries, it has moved well beyond experimental status and become a regularly applied penal measure. Australia has been lagging behind this world trend, as EM has yet not become dominant in our correctional landscape. This is even though sanctions that utilise radio-frequency and/or global positioning systems (GPS) monitoring have existed in Australia for decades. This article critically examines overseas evaluative findings of EM in relation to recidivism, cost-effectiveness and net-widening, as well as some of the issues and concerns that are associated with EM. The article then summarises and explains the limited Australian EM experience to date. It predicts that increased application of EM in Australia seems likely and should be evidence-based. In this context, there is an urgent need for increased understanding about the use and impact of EM in Australia. The article concludes with some observations about the importance of comparative analysis in this context. [ABSTRACT FROM AUTHOR]

SPIDER is the full scale prototype for the ITER Heating Neutral Beam source, hosted at the Neutral Beam Test Facility in Padova, Italy. The behavior of the beam must be thoroughly investigated to bring the machine's performance in line with ITER's requirements. In particular, ripples in the beam can affect its divergence. Measuring the AC component of the beam current can therefore help to understand the impact that the oscillations caused by the source power supplies or RF generators have on the beam optics. To minimize the occurrence of electrical discharges, SPIDER was recently operated with a mask designed to close a large number of extraction apertures. As a consequence, the space between each beamlet was substantially increased, allowing for the installation of the Beamlet Current Monitor (BCM) which enables a non-invasive direct measurement of the DC and AC components of the currents of 5 individual beamlets. A first assessment of the beamlet currents' AC components (up to 10 MHz) was performed during SPIDER's first campaign with cesium evaporation. Recurring oscillations were identified in various frequency ranges, with amplitudes reaching up to ∼ 7% of the beamlet current DC value. When possible, the ripples were correlated to oscillations due to the RF oscillators and the beatings caused by their mutual coupling, or to SPIDER's power supply systems. • The AC component of the ion beam in SPIDER was characterized with the BCM diagnostic. • The beam features ripples due to the RF oscillators and their beatings. • Power supply oscillations at multiples of 50 Hz are seen in the plasma and the beam. • A 138.8 kHz ripple caused by the EG power supply can reach very large amplitudes. [ABSTRACT FROM AUTHOR]