Radio Frequency Electromagnetic Waves Research Articles

Radio-Frequency Conductivity Evaluation Method Based on Surface/Interface Scattering of Metallic Coatings

Developing non-destructive evaluation methods for the radio frequency (RF) conductivity of conductive coatings can accelerate the performance evaluation and development of wireless communication devices. By using a split-resonator cavity to compare 800 nm copper/graphite and 1000 nm copper/graphite, we found that the RF conductivity increased by 45.5% and 82.7%, respectively, from 15 GHz to 40 GHz (pure copper was −7.2%), indicating that the bulk materials analysis method is not suitable for coating materials. Combined with electromagnetic wave theory, we believe that the critical factor lies in the additional losses of the electromagnetic waves at the copper/graphite interface and substrate. Based on the skin depth theory, the concept of triple skin depth is proposed to calculate the power loss of copper/graphite at different frequencies, considering rough Peff (including the power loss of the rough surface, copper coatings, copper/graphite interface, and graphite) compared with smooth pure copper Pc. Combined with the relationship between RF conductivity and electromagnetic wave power loss, the conductivity of copper coatings σCu at different frequencies is obtained by analyzing the measured σeff. Compared with the roughness model, the calculation error decreased from 30% to below 7%. Our study provides a theoretical basis for the regulation of the RF conductivity of metal coatings at different frequencies.

THz radiation distribution for the identification of infiltrating ductal carcinoma in human breast model: a computational study

With numerous biomedical applications of terahertz (THz) imaging, spectroscopy, and sensing, the THz regime of the spectrum is quickly emerging as an important area of research with the potential to usher in a new era in the healthcare industry. In the medical field, THz radiation has been explored to diagnose and monitor several ailments, including foot diabetes, skin dryness, wounds, and burns. Compared to X-rays, THz waves' phase sensitivity to bodily fluid levels and water results in superior contrast and stronger absorption. This feature makes THz potentially useful for the diagnosis of various malignant tumor forms because cancerous tumors have higher water molecule contents than healthy tissues. The current study presents a computational analysis of a CW-THz point-by-point scanning technique for breast cancer detection. COMSOL multiphysics platform was utilized to create a multilayer three-dimensional breast model containing an irregular-shaped infiltrating ductal carcinoma in the glandular layer. The propagation of the THz radiation in the constructed breast model was simulated based on the radio frequency module and electromagnetic waves in the frequency domain interface. Furthermore, different volumes and locations of the induced tumor were examined. The results demonstrated significant disparities in the acquired electric distribution at different tumor sizes and sites between normal and diseased breasts. The resultant electric field for healthy breast ranged from 1.1 × 10–5 to 0.61 V/m, however, the electric field ranges following tumor addition fluctuate based on its volume and location. Additionally, the position of the THz source and detector array influences the reflected THz signal.

The specific current action integral for conductors exploded by high-frequency currents

The explosive emission processes that occur at electrode surface microprotrusions may have harmful effects in a variety of electrodynamic and acceleration systems exposed to high-power radio frequency electromagnetic waves. This paper presents the results of a radiative magnetohydrodynamic simulation of the explosion of copper conductors that occur under conditions inherent in the explosion of electrode microprotrusions, i.e., at current densities of the order of 109 A/cm2. Explosions occurring under quasi-stationary and radio frequency conditions (hereinafter referred to as quasi-stationary and radio frequency explosions, respectively) were considered. It was shown that in all the considered cases, the explosion occurred at high temperatures, so that the energy deposited in the conductor by the time of explosion exceeded the sublimation energy of the conductor material. It turned out, however, that the energy deposited in the conductor under radio frequency conditions, regardless of the frequency of current oscillations, was more than two times less than that deposited under quasi-stationary conditions. The explosion time was also virtually independent of the frequency, and it was approximately three times longer than that calculated for quasi-stationary conditions. For a radio frequency explosion, the specific current action integral was somewhat less (by about 25%) than that for a quasi-stationary explosion, and its value was actually independent of frequency. At the same time, in the radio frequency regime, the radiation power coming out of the conductor substance drops strongly, and it is almost two orders of magnitude smaller compared to the radiation power in the quasistationary regime.

The survey of GSM Wireless Data Communication System using the SPSS Method

Wireless data communication using the radio spectrum, a technique called transmits signals into the environment. It can be used in one- or two-way networks using Ethernet cables or vast area networks, which may carry analogue or digital communications Infrared and radio frequency electromagnetic waves that resemble satellites are used in wireless communication technologies to send data over the air. As an illustration, consider Bluetooth, Wi-Fi, GPS, television broadcasting, wireless computer parts, and wireless phone networks like 3G and 4G. In order Wireless communications are crucial for billions of people to connect to the Internet and benefit from the contemporary digital economy. Similar to this, universally recognized guidelines for mobile phones enable individuals to use their gadgets wherever in the world. Faster information flow within firms and between customers and suppliers is a result of improved data communications. For instance, during sales calls, salespeople can immediately check inventory level and prices. In order for billions of people to use Wireless connections are crucial if you want to use the Internet and benefit from the current digital economy. Similar to how customers can also use cellphones anytime over the world according to established standards. Introduction throughout the last few decades, information and communication have changed quickly, and these innovations will have an impact on society over the coming five years. Personal lifestyles, which include an increase in cellphone use also social network usage, are one result. The topic of patient-health monitoring, which has drawn a lot of interest from researchers lately, is one in which wireless personal area networks (WBANs) are anticipated to play a significant role in the future. Creating a highly secured architecture amongst sensors and users while addressing pervasive privacy and security worries is one of the problems. In this paper, we suggest a framework for BAN communication and develop a method to protect implanted or wearable data transmission. Data security is ensured by sensors and data sinks/consumers (such as doctors or nurses) utilizing cipher text-policy attribute-based encryption. To save data in symmetric encryption format at the data sink, use (CP ABE) and a signature. O modifications enable the development of cloud infrastructure and the application of big data management. One more result of being in a classroom. In the twenty-first century, the classroom is virtual and collaborates to let both learners and instructors to attend courses utilizing online devices. Wang, Y., Lin, H., and Li, C. (2016). Due to its quick growth and popularity, digital literacy is becoming more and more significant in the educational setting. SPSS statistics is a multivariate analytics, business intelligence, and criminal investigation data management, advanced analytics, developed by IBM for a statistical software package. A long time, spa inc. Was created by, IBM purchased it in 2009. The brand name for the most recent versions is IBM SPSS statistics. Key Generation Center (KGC), Implanted and Wearable Sensors, Data Sink and Data Consumers (DCs). The Cronbach's Alpha Reliability result. The overall Cronbach's Alpha value for the model is .860which indicates 86% reliability. From the literature review, the above 50% Cronbach's Alpha value model can be considered for analysis. Emotional Intelligence the Cronbach's Alpha Reliability result. The overall Cronbach's Alpha value for the model is .860which indicates 86% reliability. From the literature review, the above 50% Cronbach's Alpha value model can be considered for analysis.

Unlocking Efficiency in Radio-Frequency Heating: Eigenfrequency Analysis for Resonance Identification and Propagation Enhancement in Nigerian Tar Sands.

Nigerian bituminous tar sands are among the world's largest deposits of bitumen and heavy oil. They are estimated to contain 38-40 billion barrels of heavy oil and bitumen, spanning approximately 120 km in length and 4-6 km in breadth. With global commitments to net zero emissions and various energy transition plans, improvements in the recovery methods for heavy oil and bitumen are being sought. To address this, renewable energy electrothermal enhanced oil recovery is considered an eco-friendly alternative. In our study, we introduce a novel Reservoir-Waveguide-Debye model. This model explores the enhancement of penetration for radio-frequency electromagnetic (EM) waves, which can be generated from renewable energy sources. These waves facilitate the viscosity reduction of heavy oil and bitumen. Through a comprehensive 2D numerical simulation employing the bulk properties of bituminous tar sands, we assess the propagation of EM fields within porous media. We utilize the industrial heating radio-frequency bandwidth of 1-60 MHz to conduct frequency domain investigations. Our analysis delves into propagation modes using eigenfrequency analysis, pinpointing the EM resonance of the tar sands. Furthermore, we investigate the impact of mesh refinement on the EM eigenfrequencies of porous media at both the microscale (400 μm) and macroscale (100 m in radial distance). Our results demonstrate the occurrence of resonance phenomena at complex eigenfrequencies around 27.12 and 54.24 MHz in both the microscale and macroscale models of the bituminous sands. This breakthrough research offers promising insights into harnessing renewable energy-driven EM waves for efficient thermal recovery processes in the Nigerian bituminous tar sands, thus fostering sustainable and eco-friendly energy solutions.

Magnetoelectrics enables large power delivery to mm-sized wireless bioelectronics.

To maximize the capabilities of minimally invasive implantable bioelectronic devices, we must deliver large amounts of power to small implants; however, as devices are made smaller, it becomes more difficult to transfer large amounts of power without a wired connection. Indeed, recent work has explored creative wireless power transfer (WPT) approaches to maximize power density [the amount of power transferred divided by receiver footprint area (length × width)]. Here, we analyzed a model for WPT using magnetoelectric (ME) materials that convert an alternating magnetic field into an alternating voltage. With this model, we identify the parameters that impact WPT efficiency and optimize the power density. We find that improvements in adhesion between the laminated ME layers, clamping, and selection of material thicknesses lead to a power density of 3.1 mW/mm2, which is over four times larger than previously reported for mm-sized wireless bioelectronic implants at a depth of 1 cm or more in tissue. This improved power density allows us to deliver 31 and 56 mW to 10 and 27-mm2 ME receivers, respectively. This total power delivery is over five times larger than similarly sized bioelectronic devices powered by radiofrequency electromagnetic waves, inductive coupling, ultrasound, light, capacitive coupling, or previously reported magnetoelectrics. This increased power density opens the door to more power-intensive bioelectronic applications that have previously been inaccessible using mm-sized battery-free devices.

Hilbert Fractal Antenna for Abnormal Discharge Detection of Transmission Equipment

The safe and stable operation of the power system can ensure people’s basic electricity needs. It also plays an important role in energy security and economic development and can contribute to environmental protection and energy conservation. If there are problems in the power system, it will not only affect people’s normal life and work but also lead to power loss or waste, thereby exacerbating the impact on the environment. With the long-term operation of transmission equipment, insulation devices are aging, leading to frequent abnormal discharges and affecting the safety and stability of the power system. Therefore, timely detection and troubleshooting are necessary. When abnormal discharge occurs in transmission equipment, it will radiate radio frequency (RF) electromagnetic waves, which are mainly concentrated between 200 MHz and 300 MHz. RF antennas that can capture signals in this frequency band can be used for detection to determine whether abnormal discharge has occurred. This article uses the Hilbert fractal antenna as the research object to analyze the impact of different orders on antenna performance and optimizes the different feeding point positions of the antenna. Finally, the antenna structure for detecting abnormal discharge is obtained. By making an actual antenna and conducting experimental analysis, the discharge detection function of the designed antenna is verified.

Detrimental effects of radiofrequency electromagnetic waves emitted by mobile phones on morphokinetics, oxidative stress, and apoptosis in mouse preimplantation embryos

Due to the increasing use of smart mobile phones, the impact of radiofrequency electromagnetic radiation (RF-EMR) on reproductive health has become a serious concern. This study investigated the effect of mobile phone RF-EMR with frequency 900–1800 MHZ on the mouse embryo morphokinetics and genotoxic effect in laboratory conditions. After ovarian stimulation in mice, the MII oocytes were collected and underwent by in vitro fertilization (IVF) method. The generated zygotes were divided into control and exposed groups. Then, the zygotes with 30 min of exposure to mobile phone RF-EMR, and the control zygotes without exposure, were incubated in the time-lapse for 5 days. The intracellular reactive oxygen species (ROS) level, morphokinetic, embryo viability rate, and Gene expression were evaluated. Exposure of zygotes to RF-EMR by inducing ROS caused a significant decrease in blastocyst viability (87.85 ± 2.86 versus 94.23 ± 2.44), delay in cleavage development (t3-t12) and also increased the time (in hours) to reach the blastocyst stage (97.44 ± 5.21 versus 92.56 ± 6.7) compared to the control group. A significant increase observed in mRNA levels of Hsp70 in exposed animals; while Sod gene expression showed a significant down-regulation in this group compared to the controls, respectively. However, there was no significant change in the transcript level of proapoptotic and antiapoptotic genes in embryos of the exposed group compared to the controls. RF-EMR emitted by mobile phone with a frequency of 900–1800 MHZ, through inducing the production of ROS and oxidative stress, could negatively affect the growth and development as well as the transcript levels of oxidative stress associated genes in the preimplantation embryos of mice.

Design of RF energy harvester for 700 MHz

Abstract Radio frequency energy harvester is the conversion of ambient radio frequency electromagnetic waves into usable electrical energy, powering low-power devices without traditional power sources. In this paper, a novel RF energy harvester is proposed for 700 MHz frequency band. For the purpose of rectification, a Greinacher voltage rectifier cum multiplier is used in the circuit and Schottky Diode HSMS-2852 is used for implementing a rectifier. The LC impedance matching is implemented to improve the circuit performance of the harvester including conversion efficiency and output voltage. Simulation of the rectifier is done using the PathWave Advanced Design System (ADS) software. The rectifier shows the optimized performance at 5 kΩ load impedance. Simulation results show the highest efficiency of 33.1 % and an output voltage of 3.2 V with 8 dBm RF power at 700 MHz input frequency.

Design and performance analysis of a rectenna system for charging a mobile phone from ambient EM waves

Advances in information technology have dramatically enhanced mobile phones. Power capacity is one of the most significant limitations of a mobile phone. As a result, efficient energy management in such devices is critical everywhere. The goal of this research is to find a way to charge electronic devices wirelessly using radio frequency (RF) electromagnetic (EM) waves (Rectenna using energy detection-based spectrum sensing). Mechanical deformations cause frequency detuning, which lowers the effectiveness of antennas and rectennas that would otherwise allow wireless communication and RF energy harvesting in the far field. A rectenna based on a stretchable multiband antenna is designed as a self-powered system to perform reliably and integrate RF power received across its multiband despite mechanical deformations. Depending on what the battery needs, the proposed multiband antenna will work at 900 MHz, 1800 MHz, 2100 MHz, and 2.45 GHz as both an RF transducer and an RF energy harvester. Depending on the received RF power density (high), the receiving RF wave will be utilized for both communication and RF energy harvesting (RF-EH) when the battery's current voltage is less than 20% (referred to as “low voltage”). Otherwise, the received RF wave will be used only for RF-EH. The installed multiband rectifiers function perfectly in terms of efficiency and bandwidth. This proposed technique would reduce the charging crisis by 60–90% depending on the location of the mobile phone or receiver of ambient EM signals. This paper could help researchers in the field of RF energy-based wireless charging systems.

New Antenna Designs to Boost the Plasma Density in Helicon Sources

Plasma can be generated using radio frequency (RF) electromagnetic waves for a large variety of applications, such as energy and propulsion generation. Often, the desire is to achieve higher densities for given input power and helicon sources have demonstrated a high efficiency. The design of the antenna that couples the wave plays a major role in the efficiency of generating the plasma particles. Many geometries were studied and compared, but the relationship between the antenna characteristics and the plasma production is still missing. In this article, we identify the power-law dependence between the plasma density and the Gain of an antenna. The latter is determined using numerical simulations in a vacuum, whereas the former is acquired experimentally. The power-law dependence is obtained using four different antenna elements operating under the same experimental conditions on the Polaris linear plasma device. The design a posteriori of a new inductive antenna with a modified quadrifilar helix topology, exhibits not only a higher gain but also confirms the power law. The confirmation of this law will significantly impact the future of many technologies that leverage helicon plasmas.

Multi-harmonic Rutherford island theory

Rutherford island theory, which governs the nonlinear evolution of tearing modes in tokamak plasmas, is generalized to take into account situations in which the conventional one-harmonic approximation is not valid. The analysis incorporates non-inductive currents driven by radio frequency (RF) electromagnetic waves injected into the plasma. A multi-harmonic tearing mode dispersion relation is derived that takes the form of a nonlinear inhomogeneous matrix eigenvalue problem. The dispersion relation is solved in the so-called two-harmonic approximation, in which only the principal Fourier harmonic of the perturbed magnetic flux and its first overtone are included in the calculation. In the absence of RF current drive, the nonlinear behavior of a tearing mode predicted in the two-harmonic approximation does not differ substantially from that predicted in the one-harmonic approximation. On the other hand, RF current drive that is sufficiently localized in the vicinity of the O-points of the mode's magnetic island chain is capable of triggering bifurcations of the O-points (which is impossible in the one-harmonic approximation). However, the current drive is incapable of triggering bifurcations of the island X-points. This finding is significant because Bardóczi and Evans [Phys. Rev. Lett. 126, 085003 (2021)] recently observed bifurcations of magnetic island chain O-points in the presence of RF current drive in the DIII-D tokamak but did not observe bifurcations of the X-points. Finally, the changes in the topology of the magnetic island flux-surfaces induced by RF current drive are found to facilitate the stabilization of the tearing mode.

Evidence of Stable Isotope 13C Causing All Cancers

Evidence for a general mechanism of genesis of all cancers is given by presenting a puzzle and using recent results of aspartame and acesulfame-K to fit the pieces of the cancer puzzle together for proof of the mechanism of oncogenesis. Aspartame and acesulfame-K have been linked to cancer. Aspartame is a modified dipeptide (methylated phenylalanine (modified) and aspartic acid), so modified amino acids were thought to be more innocuous. The author previously noted isotopically enriched and/or clumped bond-specific amino acids and oligonucleotides have different biochemical reactions for different biology. Acesulfame-K is not a peptide or oligonucleotide but it has some similar chemical structure to oligonucleoside and reversibly decomposes to affect oligonucleosides and affect cells and bacteria cells like E Coli for producing isotopically enriched amino acids indirectly. E. Coli is present in the human digestive system and is known to accelerate stable isotope enrichment of amino acids with 13C, 15N, and/or 17O. Thereby acesulfame-K and aspartame induce isotopic enrichments and excessive 13C, 15N, and/or 17O introductions into proteins and nucleic acids. Such effects of 13C isotopes as induced by the bacteria and these chemicals like aspartame and acesulfame-K may be coupled to effects of static magnetic field(s) and radio frequency electromagnetic waves for explaining the complexity of results and inconsistent results from separating these effects. Thereby the 13C isotope enriched phenylalanine and/or aspartic acid may be the basis of malfunctioning normal cells for the genesis of cancer. Further support for this theory of 13C causing cancer by ingestion of aspartame is given by also noting the mystery and confounding results of monosodium glutamate causing cancer as the glutamate is synthesized by bacterial culture and the resulting ingested glutamic acid enriched with 13C and 15N and possibly 17O causes adverse biochemistry and enzymatics (relative to glutamate from healthy plants and animals rather than the bacterial industrial glutamate in MSG) for cancer and other diseases as explaining the observation of cancer and other diseases from acute and chronic MSG ingestion over months and years. The third case of bacterial production of insulin during the last 25 years for recent correlation to insulin causing cancer relative to less cancer from older methods of insulin production is more evidence of bacterial production of amino acids and peptides causing enriched heavy isotopes and the resulting enriched amino acids and peptides causing cancer relative to ingestion of 13C enriched carbohydrates.

3D printing performance using radio frequency electromagnetic wave modified potato starch

In this study, the altered morphology, amylose content, microstructure, viscosity, and thermal properties of potato starch after being modified for different times (5, 10, 15, 20 and 30 mins) by radio frequency electromagnetic wave (RF) were studied. Obtained the most suitable RF modified time for 3D printing. The results showed that the RF treatment roughened the starch surface and reduced the amylose content, viscosity and pasting temperature of the starch. RF-treated starch gels displayed better print performance than untreated potato gels. Furthermore, RF-20 treatment offers better morphology indexes including clarity and the highest stack height, line uniformity and height retention of printed samples due to the fact that the RF treatment rearranges the internal structure of the potato starch granules, making the internal structure more stable and orderly. Overall, the RF treatment is an effective way to modify starch and optimize starch gels for 3D printing.

Alternating magnetic field initiated catalytic deconstruction of medical waste to produce hydrogen-rich gases and graphite

During the coronavirus 2019 (COVID-19) pandemic, there has been a dramatic increase in the use of medical products and personal protective equipment, such as masks, gowns, and disposable syringes, to treat patients or administer vaccines. However, this may lead to generation of large quantities of biohazardous medical waste. Here, an alternating-magnetic-field-initiated catalytic strategy is proposed to convert disposable syringes into hydrogen-rich gases and high-value graphite. Specifically, in addition to selecting heavy fraction of bio-oil as initiator, disposable syringe needles are used as radio frequency electromagnetic wave receptors to initiate the deconstruction of disposable syringe plastic. The highest H2 yield of 39.9 mmol g-1 is achieved, and 30.1 mmol g-1 is maintained after 10 cycles. Moreover, a high carbon yield of 286 mg g-1 can be obtained. Beyond disposable syringes, this strategy could help to solve the emerging issue for other types of medical waste (e.g., mask and protective clothing) disposal.

Optical Radio-Frequency Phase Measurement With an Internal-State Rydberg Atom Interferometer

We realize and model an internal-state Rydberg atom interferometer for measurement of phase and intensity of radio-frequency (rf) electromagnetic waves. A phase reference is supplied to the atoms via a modulated laser beam, enabling atomic measurement of the rf wave's phase without a rf reference wave. The rf and optical fields give rise to closed interferometric loops within the atoms' internal Hilbert space. In our experiment, we construct interferometric loops in the state space ${6{P}_{3/2},90{S}_{1/2},91{S}_{1/2},90{P}_{3/2}}$ of cesium and employ them to measure phase and intensity of a 5-GHz rf wave in a room-temperature vapor cell. Electromagnetically induced transparency on the $6{S}_{1/2}$ to $6{P}_{3/2}$ transition serves as an all-optical interferometer probe. The rf phase is measured over a range of $\ensuremath{\pi}$, and a sensitivity of 2 mrad is achieved. Measurements of rf phase and amplitude at submillimeter optical spatial resolution are demonstrated.

A passive radio frequency excited acoustic transducer

The physical processes that govern the operation of a passive acoustic transducer driven into operation by a broadcast radio-frequency electromagnetic wave are presented. The transducer is comprised of a re-entrant cavity resonator operating in its resonant TEM mode and a sensing membrane. By displacing the membrane using the acoustic pressure, one can generate an amplitude modulated radio frequency signal proportional to the product of the displacement and the excitation signal. One may use the backscattered electromagnetic signal to recover the audio signal. The results for power generation, sound transduction, and radio-frequency backscatter transmission of the audio signal are presented.

Toward an ultrasonic Internet of medical things

Wireless networked systems of “smart” miniaturized and electronically controlled implantable or wearable medical sensors and actuators will be the basis of many innovative and potentially revolutionary therapies and applications. The main obstacle in realizing this vision of smart networked implants is posed by the dielectric nature of the human body, which strongly attenuates radio-frequency electromagnetic waves used in traditional wireless technologies such as Bluetooth or WiFi. This talk will give an overview of our work exploring a radically different approach, i.e., establishing wireless networked systems in human tissues that transfer data and energy through acoustic waves at ultrasonic frequencies. We will start off by discussing applications of networked implantable medical systems.We will then analyze fundamental aspects of ultrasonic propagation in human tissues and their impact on the design of wireless networking protocols at different layers of the networking protocol stack. We will then review our work on designing and prototyping ultrasonically rechargeable and connected Internet-of-Things platforms through a closed-loop combination of mathematical modeling, simulation, and experimental evaluation.

The Effect of Magnetic Field Gradient and Gadolinium-Based MRI Contrast Agent Dotarem on Mouse Macrophages.

Magnetic resonance imaging (MRI) is widely used in diagnostic medicine. MRI uses the static magnetic field to polarize nuclei spins, fast-switching magnetic field gradients to generate temporal and spatial resolution, and radiofrequency (RF) electromagnetic waves to control the spin orientation. All these forms of magnetic static and electromagnetic RF fields interact with human tissue and cells. However, reports on the MRI technique’s effects on the cells and human body are often inconsistent or contradictory. In both research and clinical MRI, recent progress in improving sensitivity and resolution is associated with the increased magnetic field strength of MRI magnets. Additionally, to improve the contrast of the images, the MRI technique often employs contrast agents, such as gadolinium-based Dotarem, with effects on cells and organs that are still disputable and not fully understood. Application of higher magnetic fields requires revisiting previously observed or potentially possible bio-effects. This article focuses on the influence of a static magnetic field gradient with and without a gadolinium-based MRI contrast agent (Dotarem) and the cellular and molecular effects of Dotarem on macrophages.

Improvement of radio frequency heating uniformity in wheat kernels with aluminum foil sheets covered on rectangular container walls

Improving radio frequency (RF) heating uniformity is a key to obtain a good pasteurization effect while maintaining the quality of food product. The objective of this study was for providing a new method to improve the RF heating uniformity by adding aluminum foil sheets around the container walls. A 27.12 MHz, 6 kW pilot-scale RF system at an electrode gap of 110 mm was used to evaluate the heating rate and temperature distribution of wheat kernels in a rectangular container with the location, size and thickness of the foil sheet. The results showed that the RF heating behavior was influenced by foil sheets added at different oriented walls of the container. A cold spot area appeared in the place closed to the foil sheet wall at the vertically oriented addition, while a cold spot in the center and hot spots in the corners and edges still existed with the horizontally oriented addition of the sheet. The presence of foil sheet had an influence on the voltage, power input and energy efficiency. Effect of different foil sheet wall on heating behavior of samples was related to the reflection of foil sheet to RF electromagnetic wave. The heating uniformity index (λ) value decreased when the foil sheet was placed at the container bottom wall, and with increasing foil sheet size and thickness. A clearly improved RF heating uniformity can be obtained by increasing foil sheet size and thickness at the container bottom wall.