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1

Nurul, Inshirah Mohd Razali, Seman Norhudah, and Ilham Aliyaa Ishak Nur. "Design and Specific Absorption Rate of 2.6 GHz RectangularShaped Planar Inverted-F Antenna." Indonesian Journal of Electrical Engineering and Computer Science 10, no. 2 (2018): 741–47. https://doi.org/10.11591/ijeecs.v10.i2.pp741-747.

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This article presents the investigation of specific absorption rate (SAR) of a rectangular-shaped planar inverted-F antenna (PIFA) at frequency of 2.6 GHz. Initially, the design antenna is presented with parametric study concerning the dimensions of antenna patch length, shorting plate, ground plane and substrate. The proposed PIFA antenna has -20.46 dB reflection coefficient and 2.383 dB gain. The PIFA’s SAR is correlated with the antenna gain and excitation power. The analysis shows that higher gain contributes to a lower SAR value. While, the higher excitation power causes a higher SAR value. All the design and analysis are performed using the CST Microwave Studio.
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2

Nur, Ilham Aliyaa Ishak, Seman Norhudah, and Asmawati Samsuri Noor. "Specific Absorption Rate Assessment of Multiple Microstrip Patch Antenna Array." TELKOMNIKA Telecommunication, Computing, Electronics and Control 16, no. 4 (2018): 1500–1507. https://doi.org/10.12928/TELKOMNIKA.v16i4.9041.

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Interaction between electromagnetic field (EMF) radiated from multiple antennas and human body is crucial to be explored as multiple antennas are the essential implemented devices to achieve the requirements of the future evolved fifth generation (5G) technology. Thus, this article presents a significant study of the radiated EMF effect from a single, and multiple antennas towards human through the assessment of specific absorption rate (SAR). The single antenna, 1 x 2, 1 x 3 and 1 x 4 arrays of microstrip patch antennas are designed to cover mobile operating frequencies of 0.8, 0.85, 0.9, 1.8, 2.1 and 2.6 GHz. Two types of human head phantoms are implemented in this study, which are specific anthropomorphic mannequin (SAM) and Voxel head model that placed close to single antenna or antenna array to investigate the penetration of EMF towards the human tissue. The single antenna or antenna array is placed with fixed distance of 10 mm from the phantom, which excited by maximum allowable power of 19 dBm in CST Microwave Studio 2016. The effect of the radiated EMF that quantified by SAR parameter, which depicts satisfying results against the established standard limits at averaged 1g and 10g mass of tissues for all designated frequencies that utilized for single and multiple antennas.
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3

Gerhardt, D. "Definition of a parameter for a typical specific absorption rate under real boundary conditions of cellular phones in a GSM networkd." Advances in Radio Science 1 (May 5, 2003): 335–38. http://dx.doi.org/10.5194/ars-1-335-2003.

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Abstract. Using cellular phones the specific absorption rate (SAR) as a physical value must observe established and internationally defined levels to guarantee human protection. To assess human protection it is necessary to guarantee safety under worst-case conditions (especially maximum transmitting power) using cellular phones. To evaluate the exposure to electromagnetic fields under normal terms of use of cellular phones the limitations of the specific absorption rate must be pointed out. In a mobile radio network normal terms of use of cellular phones, i.e. in interconnection with a fixed radio transmitter of a mobile radio network, power control of the cellular phone as well as the antenna diagram regarding a head phantom are also significant for the real exposure. Based on the specific absorption rate, the antenna diagram regarding a head phantom and taking into consideration the power control a new parameter, the typical absorption rate (SARtyp), is defined in this contribution. This parameter indicates the specific absorption rate under average normal conditions of use. Constant radio link attenuation between a cellular phone and a fixed radio transmitter for all mobile models tested was assumed in order to achieve constant field strength at the receiving antenna of the fixed radio transmitter as a result of power control. The typical specific absorption rate is a characteristic physical value of every mobile model. The typical absorption rate was calculated for 16 different mobile models and compared with the absorption rate at maximum transmitting power. The results confirm the relevance of the definition of this parameter (SARtyp) as opposed to the specific absorption rate as a competent and applicable method to establish the real mean exposure from a cellular phone in a mobile radio network. The typical absorption rate provides a parameter to assess electromagnetic fields of a cellular phone that is more relevant to the consumer.
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4

Jemima Priyadarshini, S., and D. Jude Hemanth. "Investigation of Nanomaterial Dipoles for SAR Reduction in Human Head." Frequenz 73, no. 5-6 (2019): 189–201. http://dx.doi.org/10.1515/freq-2018-0220.

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Abstract The Nanomaterial is a pioneer in the field of modern research for its unique properties. Human exposure analysis is inevitable due to the rapid growth in technology. The concern for human welfare indicates a need for reduction of human exposure towards the radiation caused by the devices. The dielectric properties of the nanomaterials can be ideal for exploration in the field of biomedical engineering. Specific absorption rate (SAR) is a vital parameter for exposure analysis. This paper investigates the impact of Nanomaterials on the human exposure analysis. For this purpose, a dipole radiating structure operating at GSM frequency of 900 MHz and 1800 MHz are designed with conventional Copper material and compared with Carbon nanomaterials such as Graphene, Single-walled carbon nanotube (SWCNT) and Multi-walled carbon nanotube (MWCNT) for performance evaluation. Further, the specific absorption rate estimates absorption of radiation in IEEE Sam phantom human head with equivalent tissue properties. The comparison of calculated SAR with the radiating structures that are designed with the equivalent properties of that of Nanomaterials. The evaluation of Nanomaterial Antennas at the center frequency is estimated, and performance is evaluated. The designed Nanomaterials interact with IEEE SAM Phantom and SAR is calculated. The analysis of SAR impact with nanomaterials is investigated in this work.
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5

Iacob, Nicusor. "Pitfalls and Challenges in Specific Absorption Rate Evaluation for Functionalized and Coated Magnetic Nanoparticles Used in Magnetic Fluid Hyperthermia." Coatings 15, no. 3 (2025): 345. https://doi.org/10.3390/coatings15030345.

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In recent decades, magnetic hyperthermia (MH) has gained considerable scientific interest in cancer treatment due to its ability to heat tumor tissues deeply localized inside the body. Functionalizing magnetic nanoparticles (MNPs) with vector molecules via specific organic molecules that coat the particle surface has enabled targeting particular tissues, thereby increasing the specificity of MH. MH relies on applying radiofrequency (RF) magnetic fields to a magnetic nanoparticle distribution injected in a tumor tissue. The RF field energy is converted into thermal energy through specific relaxation mechanisms and magnetic hysteresis-driven processes. This increases the tumor tissue temperature over the physiological threshold, triggering a series of cellular apoptosis processes. Additionally, the mechanical effects of low-frequency AC fields on anisotropic MNPs have been shown to be highly effective in disrupting the functional cellular components. From the macroscopic perspective, a crucial parameter measuring the efficiency of magnetic nanoparticle systems in MH is the specific absorption rate (SAR). This parameter is experimentally evaluated by different calorimetric and magnetic techniques and methodologies, which have specific drawbacks and may induce significant errors. From a microscopic perspective, MH relies on localized thermal and kinetic effects in the nanoparticle proximity environment. Studying MH at the cellular level has become a focused research topic in the last decade. In the context of these two perspectives, inevitable questions arise: could the thermal and kinetic effects exhibited at the cellular scale be linked by the macroscopic SAR parameter, or should we find new formulas for quantifying them? The present work offers a general perspective of MH, highlighting the experimental pitfalls encountered in SAR evaluation and motivating the necessity of standardizing the devices and protocols involved. It also discusses the challenges that arise in MH performance evaluation at the cellular level.
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6

Wang, Mengxi, Guohui Yang, Yu Li, and Qun Wu. "In Vitro Physical and Biological Evaluations of a 2.4 GHz Electromagnetic Exposure Setup." Applied Computational Electromagnetics Society 36, no. 1 (2021): 82–88. http://dx.doi.org/10.47037/2020.aces.j.360112.

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In this paper, a 2.4 GHz electromagnetic radiation system for cells in vitro was designed from the perspective of optimal energy coupling of cell samples. The validity of the design was verified by FDTD simulation, physical test and biological experiment. The electromagnetic parameters of SAR (Specific Absorption Rate) and temperature rise were obtained by FDTD simulation. The validation of temperature simulation was confirmed by comparing the actual measurement data and the simulation data. The SAR relative uniformity between samples was tested by cell biological experiment, in which ROS (Reactive Oxygen Species), a typical and sensitive biological parameter reacting to electromagnetic radiation in cells, of different sample dishes induced by 2.4 GHz electromagnetic radiation with an incident power of 0.5 W was analyzed. We found that the size of cell dish affects the energy coupling intensity, the polarization characteristics of electromagnetic wave determines the distribution pattern of SAR, and the uniformity of sample energy absorption in this radiation system is good.
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7

Okoye, Obiora E., Bubu Atisi, Melvin Idonje, and Ezekiel O. Agbalagba. "Evaluating the Effect of Electromagnetic Field from Electrical Distribution Substations in Aguata, Nigeria." International Journal of Research and Innovation in Applied Science IX, no. VI (2024): 414–24. http://dx.doi.org/10.51584/ijrias.2024.906037.

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This study evaluates the radiation safety implications of electromagnetic field (EMF) from electrical distribution sub-stations in Aguata Local Government Area (LGA), Anambra State, Nigeria, using the EMF meter with a laser distance meter in-situ. Ten (10) locations of 11KV distribution sub-stations were mapped out and used for the study. The results of the in-situ measurement of Electric Field (E) and Magnetic Field (H) were used to evaluate the Power Density (S), Specific Absorption Rate (SAR) and Statistical analysis which includes descriptive statistics, inferential statistical tests (T-test) and graphical analysis to evaluate significant differences of EMF levels between different locations. The EMF emitted by these distribution substations was examined using data from the various locations. The results obtained show that EEDC Office has the highest electric field of 0.6633 V/m, while Oko Road has the second highest of 0.7783 V/m. The magnetic field intensity varies across locations, with Oko Road having the largest of 1.3317 A/m. Power density varied, with Oko Road having the highest 1.0365 W/m2 and Stadium having the lowest 0.1011 W/m2. The Specific Absorption Rate (SAR) ranging from 0.0001 to 0.0005 W/Kg showed consistent rates across locations. The International Commission on Non-Protection of Electromagnetic Fields (ICNIRP) sets EMF exposure regulations from 0-300 GHz at the exposure values of, E = 10,000V/m, H = 4×104 A/m, S = 50W/m2, SAR = 10W/kg. In this study, electric field, magnetic field, power density, and specific absorption rate (SAR) values varied widely between stations, with the magnetic field accounting for 45.25% of total electromagnetic exposure. The exposure to EMF emanating from distribution substations in Aguata LGA does not pose any health effect or any health hazards to the general public comparing the measured data with the standard guideline of ICNIRP.
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8

Subramaniam, Mahendrakumar, Gokul Chandrasekaran, Jayachandran T, Malathi SR, Neelam Sanjeev Kumar, and Vanitha Krishnan. "Design and Fabrication of L and U Slot Wearable Antennas for Wireless Body Area Network Applications." International Research Journal of Multidisciplinary Scope 05, no. 04 (2024): 969–90. http://dx.doi.org/10.47857/irjms.2024.v05i04.01536.

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Wearable microstrip patch antennas are compact, low-profile antennas designed for integration into wearable devices, offering wireless communication capabilities. Wireless body area networks (WBANs) are a promising technology with potential applications in a variety of biomedical fields. Patient surveillance, healthcare monitoring, and medical diagnostics are a few examples. The Specific Absorption Rate (SAR) in close proximity to the body, as well as the device's size, vulnerability to the environment, and limited bandwidth, all have an impact on its efficacy and dependability. This paper gives a thorough look at the planning, testing, and production of a wearable antenna that works at 2.4 GHz and has unique U-cut and double L-cut slots inside a patch antenna structure. The primary focus is on reducing specific absorption rate (SAR) exposure while maintaining optimal performance metrics. We rigorously analyze parameters such as SAR reduction, VSWR, return loss, radiation pattern, gain, and efficiency using the High Frequency Structural Simulator (HFSS). This SAR-aware wearable antenna design, which includes parameter analysis, addresses concerns about people being too close to electromagnetic radiation from wireless devices. We tested the fabricated antennas using a VNA testing instrument. Following the testing process, we conducted a comparison between the simulation and fabrication results. Upon comparison, we found that the antenna's software simulation and hardware testing results were identical. They both operated at 2.4 GHz and achieved a gain of 20 dB. This indicates a successful design and validation process for the fabricated antenna.
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9

Mahmud, Sagar. "Analysis of mobile phone radiation effect on human body using specific absorption rate." Asian Journal of Applied Science and Engineering 11, no. 1 (2022): 7–19. http://dx.doi.org/10.18034/ajase.v11i1.4.

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The use of mobile phones is rising everyday both in civic and rustic areas in Bangladesh. Every mobile phone disperses electromagnetic energy. This radiation or electromagnetic wave can penetrate into the human body. Specific absorption rate and change in temperature are the vital parameter to find the dominant effects assess on the human body. This paper explores the radiation impact of mobile phones. A mathematical equation is used to evaluate the local specific absorption rate and change in temperature at Skin, Fat, Bone, Brain, Eye, Muscle tissues at the frequency of 800MHz, 900 MHz, 1800 MHz, 2100 MHz, 2.5GHz, 2.6GHz, 3.4GHz, 3.5GHz, and 3.6GHz. The calculations are performed at different distances and exposure times of mobile phone. A simple radio frequency detection circuit has been designed to find the radiated power of different frequency. The highest specific absorption rate is calculated for skin, brain, eye tissue. Child tissue absorption rate is higher than the adult. When the radiated power of mobile phone is high the specific absorption rate for different tissue cross the safety limit. This paper also recommends the ways to diminish the effects of SAR. It is suggested that these methods will decrease the health risks. This work will be very helpful to understand the bad effect of using mobile phones and the way of reducing this effect.
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10

S., M. Shah, A. Rosman A., A. Z. A. Rashid M., et al. "A compact dual-band semi-flexible antenna at 2.45 GHz and 5.8 GHz for wearable applications." Bulletin of Electrical Engineering and Informatics 10, no. 3 (2021): pp. 1739~1746. https://doi.org/10.11591/eei.v10i3.2262.

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In this work, a compact dual-band semi-flexible antenna operating at 2.45 GHz and 5.8 GHz for the industrial, scientific and medical (ISM) band is presented. The antenna is fabricated on a semi-flexible substrate material, Rogers Duroid RO3003™ with a low-profile feature with dimensions of 30×38 mm2 which makes it a good solution for wearable applications. Bending investigation is also performed over a vacuum cylinder and the diameters are varied at 50 mm, 80 mm and 100 mm, that represents the average human arm’s diameter. The bending investigation shows that reflection coefficients for all diameters are almost similar which imply that the antenna will operate at the dual-band resonant frequencies, even in bending condition. The simulated specific absorption rate (SAR) in CST MWS® software shows that the antenna obeys the FCC and ICNIRP guidelines for 1 mW of input power. The SAR limits at 2.45 GHz for 1 g of human tissue is simulated at 0.271 W/kg (FCC standard: 1.6 W/kg) while for 10 g is at 0.0551 W/kg (ICNIRP standard: 2 W/kg. On the other hand, the SAR limits at 5.8 GHz are computed at 0.202 W/kg for 1 g and 0.0532 W/kg for 10 g.
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11

Liu, Nan N., Alexander P. Pyatakov, Mikhail N. Zharkov, et al. "Optimization of Zn–Mn ferrite nanoparticles for low frequency hyperthermia: Exploiting the potential of superquadratic field dependence of magnetothermal response." Applied Physics Letters 120, no. 10 (2022): 102403. http://dx.doi.org/10.1063/5.0082857.

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Magnetothermal applications of nanoparticles in biomedicine are currently limited by low thermal responses to oscillating magnetic fields on one side and by detrimental physiological effects of electromagnetic radiation on the other side. In this paper, using Zn–Mn ferrite nanoparticles, we demonstrate that an appropriate choice of size and chemical composition of magnetic nanoparticles results in the superquadratic (upto 5th power) dependence of the Specific Absorption Rate (SAR) on a magnetic field (SAR proportional to H5). This gives an opportunity to obtain SAR values above 10 W/g in an oscillating magnetic field, while maintaining the field-frequency product at a level close to the physiological Brezovich's limit ∼ 109A/(m s).
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12

Raja, Ahmed, Sareen Prince, Kumar Vikram, Jatin, Parveen Alnoor, and Kumar Nehra Rajiv. "Dual Band Implantable Antenna Using Pin and Slot for Bmds." Journal of Advancement in Communication System 6, no. 2 (2023): 41–51. https://doi.org/10.5281/zenodo.7985710.

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<em>In this paper, we discussed the implantable circular patch antenna for medical devices, after&nbsp; review of this paper, readers will understand about implantable antenna and how these implantable antennas become boon for medical industry. Majorly, these antennas are used in implantable medical devices (IMDs). The implantable devices are placed inside the body where they track bio-signals (like blood pressure and temperature signals) and transmit the data to the external device. This paper represents the highly miniaturization antenna having volume of 7.065 mm<sup>3</sup>. The effectiveness of the antenna is thoroughly examined in terms of reflection coefficient, gain, SAR, Impedance Bandwidth values. The substrate material featured in Antenna is FR4 epoxy because it helps to increase the antenna&#39;s bandwidth and is far less expensive than Rogers, giving an edge over other substrate materials. It has a dielectric constant of 4.4. The proposed antenna &nbsp;&nbsp;&nbsp;exhibits ISM band from 2.4 GHz to 2.48 GHz. A shorting pin and slots that offer ISM band, an acceptable SAR of 237.23 W/Kg, and a directed gain of -20.117 dB. To achieve wireless charging, the implantable antenna must be designed with dual bands (ISM bands). Here the proposed antenna shows characteristics of dual band at ISM band (2.4 GHz to 2.48 GHz) and (7.625 GHz). One band is used for data transmission during telemetry sessions and the other in order to enable wireless charging without affecting the location of IMDs inside the human body. The band uses radiation and transforms it into DC power using a rectifier and filter (integral BMD components). The suggested implanted antenna&#39;s parametric analysis has been carefully examined. The use of circular microstrip patch antennas is extensive, particularly in the domains of pharmaceutical, military, mobile, and planetoid communications.</em>
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13

Smith, Deandrae L. W., Surabhi Wason, Griffiths G. Atungulu, and Rebecca M. Bruce. "Optimizing Radiofrequency Exposure Parameters for One-Pass Drying of High-Moisture Paddy Rice." Applied Engineering in Agriculture 40, no. 2 (2024): 199–210. http://dx.doi.org/10.13031/aea.15842.

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Highlights The utilization of standardized Radiofrequency (RF) exposure parameters ensures safety and process consistency. Equations were used to estimate Power Density (S), Specific Absorption Rate (SAR), and Electric Field Intensity (E). One-pass RF drying effectively lowered paddy rice (Cultivar [cv.] XL-753) initial Moisture Content (MC; 20.4% w.b.) to safe levels (=13.5% w.b.) with SARAdjusted of 1.87 × 106 J, E of 46.82 V/m, and S of 300,000 W/m² (6,000 W/kg). Higher SARAdjusted values impacted paddy rice surface lipid content and milling yields, while minor changes in color and viscosity showed inconsistent and subtle practical effects. Abstract. Radiofrequency (RF) heating utilizes high-frequency electromagnetic waves to induce heat within materials via molecular friction. This method offers rapid, even heating, deep penetration, and energy efficiency. Nevertheless, there is a dearth of research on RF exposure parameters concerning food processing. Investigating these parameters is crucial for RF process optimization, setting safety guidelines, and guaranteeing product quality. This research clarifies RF exposure parameters through the one-pass drying of high moisture content (MC) long-grain paddy rice (cultivar [cv.] XL-753) at an initial MC of 20.4% wet basis (w.b.) to a final of MC of = 13.5% w.b. (safe MC for storage). The specific objectives of this research were to: 1. Advocate the utilization of standardized RF exposure parameters (Specific Absorption Rate, SAR; Electric Field Intensity, E; and Power Density, S) of food and agricultural products, aiming to simplify RF processing, fostering consistency and safety in operations. 2. Estimate the RF exposure parameters associated with the one-pass RF drying process. 3. Determine the RF exposure parameters’ influence on rice physicochemical attributes of Milled Rice Yield (MRY), Head Rice Yield (HRY), Color Parameters (L* a* b*), Surface Lipid Content (SLC), and Pasting Properties. Using a pilot-scale parallel-plate RF heating system (6 kW, 27.12 MHz) with a 105 mm product-to-emitter gap, RF exposure parameters were determined: E = 46.82 V/m; EEff = 33.11 V/m; S = 300,000 W/m²; SAR = 2,224.95 W/kg. Rice samples underwent RF exposure durations of 360, 600, and 840 s, resulting in SARAdjusted levels of 0.80 × 106, 1.33 × 106, and 1.87 × 106 J, respectively. Half of the RF-processed paddy rice underwent tempering, which involved immediately transferring paddy rice after RF treatments into sealed glass jars and then into an incubator set to a constant temperature of 60°C for a duration of 4 h. RF processed samples at the highest SARAdjusted tested (1.87 × 106 J) followed by tempering resulted in MC reductions of 6.7% pt. w.b., final MC of 14.0% w.b., MRY, HRY, and SLC of 70.80%, 47.38%, and 0.47%, respectively. Non-tempered samples at the same SARAdjusted level had MC reductions of 7.34% pt. w.b., final MC of 13.1% w.b., MRY, HRY, and SLC of 60.91%, 4.53%, and 0.43%. Tempering and SARAdjusted values slightly affected rice physicochemical characteristics of color and viscosity. However, the differences were minor and inconsistent. To ensure optimal quality in large-scale RF drying of rice, it is crucial to avoid SARAdjusted levels exceeding 1.33 × 106 J. Exceeding this threshold has been shown to cause overheating, adversely impacting the grain’s quality. Moreover, implementing a tempering process post-drying is also essential in mitigating these detrimental effects. Keywords: Color, Electric field intensity (E), Lipids, Milling yields, Power density (S), Radio-frequency (RF), Rice drying, Specific absorption rate (SAR), Viscosity.
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14

Necula, E. E., and I. E. Aciu. "Study on Some Effects of Radiofrequency on Human Brain." Bulletin of the Transilvania University of Brasov. Series I - Engineering Sciences 14(63), no. 2 (2022): 15–22. http://dx.doi.org/10.31926/but.ens.2021.14.63.2.2.

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The study is based on determining the impact of radiofrequency on humans by taking into account the SAR (Specific Absorption Rate) value and the temperature elevation through the brain. SAR represents a parameter given by each phone manufacturer regarding the amount of radiation emitted and absorbed by the brain. Was used the FlexPDE software to solve the Pennes’ bioheat equation and to determine the temperature elevation in the brain due to radiofrequency. In the graphical output, it was observed a sudden temperature rise above the normal brain one, of 370C, but stabilization after a short period. This study targets to make people aware of both the advantages and disadvantages of GSM usage.
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15

Nakamura, Takashi, Shinobu Tokumaru, and Shiro Itoh. "Reduction of specific absorption rate (SAR) in human body by a lossy dielectric shield." Electronics and Communications in Japan (Part I: Communications) 81, no. 10 (1998): 71–80. http://dx.doi.org/10.1002/(sici)1520-6424(199810)81:10<71::aid-ecja8>3.0.co;2-s.

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16

Constantinescu, Claudia, Claudia Pacurar, Adina Giurgiuman, et al. "The Influence of Human Tissues on the Patch Antennas' Parameters." TRANSACTIONS ON ELECTROMAGNETIC SPECTRUM 2, no. 1 (2023): 1–11. https://doi.org/10.5281/zenodo.7646244.

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In a lot of studies from literature was analyzed the influence of antennas on human body. In this article the study reflects the opposite, the influence of human tissue on antennas&rsquo; parameters. In this study different types of human tissues are modelled in the vicinity of the patch antenna to analyze their influence on antennas&rsquo; parameters. To model the patch antenna, the authors developed and implemented an algorithm dedicated to the determination of the antenna&rsquo;s geometrical dimensions in terms of dielectrics&rsquo; material properties and their standard dimensions, all gathered by the authors in a very useful database. Using our algorithm, we can quickly find the antennas geometrical parameters needed for its numerical modelling and practically construction. The antenna geometry is obtained with our algorithm and next is modelled in the presence of three types of tissue: skin, muscle, and fat. The directivity, S-parameters and specific absorption rate in the tissues are determined, considering different distances between them. Analyzing our results, we can conclude that the normal functioning of the antenna is influenced by the presence of human tissues in their immediate vicinity.
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17

Pudipeddi, S. S., P. V. Y. Jayasree, and S. G. Chintala. "Polarization Effect Assessment of Sub-6 GHz Frequencies on Adult and Child Four-Layered Head Models." Engineering, Technology & Applied Science Research 12, no. 4 (2022): 8954–59. http://dx.doi.org/10.48084/etasr.5096.

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Nowadays, with the extensive use of mobile phones, the Electromagnetic (EM) radiation penetration from Radio Frequencies (RFs), particularly into the human head, is an issue that needs resolving. Some serious biological hazards occur inside the human body due to RF radiation accumulation. The RF radiation can be minimized by embodying shielding and coating materials on the front side of the mobile handset. The novelty of the proposed work is the use of mathematical analysis in calculating the Specific Absorption Rate (SAR) absorbed by planar four-layer adult and child head models when exposed to mobile smartphone RF radiation. The variation of SAR with the Angle of Incident (AoI) of the EM wave considers Transverse Electric (TE) and Transverse Magnetic (TM) Polarization. The SAR absorption alteration with the AoI of the EM wave is calculated with the help of the shielding effectiveness parameter of the external Polyethylene Terephthalate (PET) shield coated with conductive copper (Cu) mesh, forming a laminated shield using the methodology of the transmission line method. Furthermore, the SAR variation with AoI for both human head models is calculated theoretically at Sub-6 GHz mobile frequencies of 4.5GHz and 3.6GHz. SAR of 7.41e-12 W/kg and 4.41e-11 W/kg is achieved theoretically for adult and child head models respectively, at 89° TE polarization at 4.5GHz.
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18

Inum, Reefat, Md Masud Rana, Kamrun Nahar Shushama, and Md Anwarul Quader. "EBG Based Microstrip Patch Antenna for Brain Tumor Detection via Scattering Parameters in Microwave Imaging System." International Journal of Biomedical Imaging 2018 (2018): 1–12. http://dx.doi.org/10.1155/2018/8241438.

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A microwave brain imaging system model is envisaged to detect and visualize tumor inside the human brain. A compact and efficient microstrip patch antenna is used in the imaging technique to transmit equivalent signal and receive backscattering signal from the stratified human head model. Electromagnetic band gap (EBG) structure is incorporated on the antenna ground plane to enhance the performance. Rectangular and circular EBG structures are proposed to investigate the antenna performance. Incorporation of circular EBG on the antenna ground plane provides an improvement of 22.77% in return loss, 5.84% in impedance bandwidth, and 16.53% in antenna gain with respect to the patch antenna with rectangular EBG. The simulation results obtained from CST are compared to those obtained from HFSS to validate the design. Specific absorption rate (SAR) of the modeled head tissue for the proposed antenna is determined. Different SAR values are compared with the established standard SAR limit to provide a safety regulation of the imaging system. A monostatic radar-based confocal microwave imaging algorithm is applied to generate the image of tumor inside a six-layer human head phantom model. S-parameter signals obtained from circular EBG loaded patch antenna in different scanning modes are utilized in the imaging algorithm to effectively produce a high-resolution image which reliably indicates the presence of tumor inside human brain.
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19

Yi, Miao, Boqi Wu, Yang Zhao, Tianbo Su, and Yaodan Chi. "Safety Assessment and Uncertainty Quantification of Electromagnetic Radiation from Mobile Phones to the Human Head." Applied Sciences 13, no. 14 (2023): 8107. http://dx.doi.org/10.3390/app13148107.

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With the rapid development of the mobile communication technology, the design of mobile phones has become more complex, and research on the electromagnetic radiation from mobile phones that reaches the human head has become important. Therefore, first of all, a model of mobile phone daily use was established. Then, based on the established simulation model, the safety of human head exposure to mobile phones was evaluated. The generalized polynomial chaos (gPC) method was used to establish a proxy model of the specific absorption rate (SAR) of the human head at different frequencies to perform a parameter uncertainty quantification (UQ). Finally, the Sobol method was used to quantify the influence of relevant variables on the SAR. The simulation results showed that the gPC method can save time and cost while ensuring accuracy, and the SAR value is greatly influenced by the electromagnetic materials of the mobile phone shell. Combined with the above analysis, this paper can provide reasonable suggestions for the design of mobile phone electromagnetic materials.
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20

ADEJUMOBI, I. A., J. F. ORIMOLADE, and B. A. OMOTAYO. "MEASUREMENT AND ANALYSIS OF RADIO FREQUENCY ENERGY AND SPECIFIC ABSORPTION RATE FROM GLOBAL SYSTEM FOR MOBILE COMMUNICATIONS IN FUNAAB, OGUN STATE, NIGERIA." Journal of Natural Sciences Engineering and Technology 14, no. 1 (2016): 120–29. http://dx.doi.org/10.51406/jnset.v14i1.1501.

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This work measured and analyzed the Radio Frequency (RF) power densities to determine the absorption rate on human body from the four available 900 MHz Global System for Mobile communication (GSM) base stations, at some selected points in the Federal University of Agriculture, Abeokuta (FUNAAB), Nigeria.ª¤? Measurements were conducted using Frequency-selective spectrum analyzer (Nokia 6800 Network Drive Tester) to determine the RF Power Densities (S), Electric Field Intensities (E) and the Specific Absorption Rates (SAR), using Airtel Base station as reference sample point. Standard Units values of the measured variables were obtained using standard mathematics equations. Out of ten (10) selected sampling points the maximum RF exposure was obtained at COLENG upstairs with its the power density equal 15.2 ª¤?W/m2 which is 3.7 x 10-4% of the maximum allowable value of the maximum exposure at 900 MHz. The recorded highest electric field intensities was 75.7 x 10-3 V/m, which is 0.18% of that specified by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) maximum public exposure levels for 900 MHz. The highest obtained SAR value was 4.2635 x 10-3 W/kg which is 5.329% of the maximum recommended exposure level for the head region and brain tissue at 900 MHz. The results from this study are useful sources of environmental information and database to the FUNAAB communityª¤?
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21

Tapasy, Rabeya, Eshita Khatun Mst., and Akhter Hossain Syed. "Effect of Cellular Tower Radiation towards Human Tissues at Bangladesh Context." International Journal of Engineering and Advanced Technology (IJEAT) 9, no. 3 (2020): 2794–800. https://doi.org/10.35940/ijeat.C5941.029320.

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With the rapid technological advancement the increasing cell phone dependency has led to set up cellular towers in numerous communities. These towers are known as base stations, have antennas and electronic equipment that transmit and receive RF (radio-frequency) signals. Various experimental and epidemiological analysis have been done for searching the potential effect of BTS (Base Transceiver Station) establishment in residential areas and result shows significant health issues, as the RF radiation can mess with the human body&rsquo;s own EMFs. Therefore, for ensuring public safety it is essential to ascertain the minimum safe distance of establishing BTSs from locality. In this calculation based empirical work, on the basis of SAR (Specific Absorption Rate) mentioned by the World Health Organization, we have analyzed and proposed the minimum reasonable distance of nine major human tissues for being affected by the radiation. This analysis has been done at different frequency bands based on a specific type of antenna at Bangladesh context.
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22

Goswami, Niloy, and Md. Abdur Rahman. "A9.73 GHzwide-band off-body patch antenna for biomedical applications." Indonesian Journal of Electrical Engineering and Computer Science 33, no. 1 (2024): 151–58. https://doi.org/10.11591/ijeecs.v33.i1.pp151-158.

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The primary goal of this study is to design a simple antenna that has a wide bandwidth and low return loss for biomedical applications. The paper shows the recommended antenna&rsquo;s three-stage modeling, with the goal of assessing every important parameter while a Teflon or polytetrafluoroethylene (PTFE) polymer substrate is used. In order to better comprehend, a comparison with prior studies employing teflon and similar substrate materials is conducted for the proposed patch antenna. The analysis includes the phantom model, evaluating performance criteria such as specific absorption rate (SAR), return loss, bandwidth, and gain values relevant to biomedical applications. The antenna works at two different frequencies: 9.73 and 9.39 GHz, one in free space and another in a skin-cotton layer. The bandwidth of the antenna is 4.067 GHz in free space at the resonance frequency of 9.73 GHz, where the return loss is -62.18 dB. The performance of the proposed antenna in the field of biomedical applications, its underlying reasons, and its impacts are discussed in detail in this study.
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23

Oprea, Petronela-Camelia, Marius Valerian Păuleţ, and Alexandru Sălceanu. "Study Upon the Influence of Mobile Phone Communication Technology on Sar Distribution." Bulletin of the Polytechnic Institute of Iași. Electrical Engineering, Power Engineering, Electronics Section 69, no. 4 (2023): 45–56. https://doi.org/10.2478/bipie-2023-0021.

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Abstract From the multitude of electromagnetic field sources that are part of our daily environment, wireless communications occupy a dominant position. Among the devices that use this type of communications, the closest to our hearts (both literally and figuratively) is the mobile phone. This accumulation of radio frequency electromagnetic waves is absorbed (partially) by the bodies they encounter, resulting in their heating. This unwanted increase in temperature is most faithfully illustrated by the distribution of the Specific Absorption Rate (SAR) parameter. The most accurate results can be provided by “in silico” tests, simulations performed with the help of human phantoms obtained with the help of slices provided by Computer Tomograph (CT) and Magnetic Resonance Imaging (MRI) technologies. In our paper, comparative results of the SAR distribution obtained around the heart are presented, for 6 distinct situations. Conclusions and useful recommendations are presented, resulted from these simulations developed in CST Studio Suite.
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24

Song, Lina, Changzhi Yan, Wei Zhang, et al. "Influence of Reaction Solvent on Crystallinity and Magnetic Properties of MnFe2O4Nanoparticles Synthesized by Thermal Decomposition." Journal of Nanomaterials 2016 (2016): 1–8. http://dx.doi.org/10.1155/2016/4878935.

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This study reports the synthesis of three kinds of manganese-doped magnetic ferrite nanoparticles (MnFe2O4) in benzyl ether, octyl ether, and 1-octadecene by a simple and low cost thermal decomposition method. It was found that benzyl ether results in a dramatic improvement in nanoparticle crystallinity owing to its stronger reducibility compared to octyl ether and 1-octadecene, as demonstrated by X-ray diffraction and TEM measurements. Raman spectroscopy detection also indicated that the reducing solvent of benzyl ether was in favor of forming magnetite-like structure ferrite, while maghemite-like structured ferrite was obtained in octyl ether and 1-octadecene. The saturation magnetization (MS) of MnFe2O4synthesized in benzyl ether was 85 emu/g [Fe], which was 3 and 5 times larger than MnFe2O4synthesized in octyl ether and 1-octadecene, respectively. The specific absorption rate (SAR) of MnFe2O4nanoparticles synthesized in benzyl ether was 574 W/g, while MnFe2O4nanoparticles synthesized in octyl ether and 1-octadecene have had much smaller SAR of 76 and 33 W/g, respectively. MnFe2O4nanoparticles synthesized in benzyl ether also exhibit higher relaxivity (r2=207 mM−1 s−1) than those synthesized in octyl ether and 1-octadecene (r2=65and 22 mM−1 s−1). It was obvious that MnFe2O4nanoparticles synthesized in reducing benzyl ether have higher crystallinity and thus higherMS, SAR, andr2values, which can serve as a better candidate for hyperthermia and magnetic resonance imaging.
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25

Sudsiri, Chadapust J., and Raymond J. Ritchie. "Influence of Na+ disorder on cytoplasmic conductivity and cellular electromagnetic (EM) energy absorption of human erythrocytes (PONE-D-21-36089)." PLOS ONE 18, no. 2 (2023): e0277044. http://dx.doi.org/10.1371/journal.pone.0277044.

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Cytoplasmic conductivity of human erythrocytes may be significantly disturbed by the composition of the external suspending media. Effects of external NaCl on cytoplasmic conductivity of human erythrocyte (Human Red Blood Cells, HRBC) were investigated in a simple NaCl system. Using thermodynamic theory cytoplasmic conductivities could be calculated from internal [K+], [Na+], [Cl-] and [HCO3-]. Effect of cell volume and cell water changes were introduced and allowed for using the Debye-Hückel-Onsager relation and Walden’s rule of viscosity. Cell volume and cell water change of HRBCs were measured in suspending isotonic solutions with conductivities from 0.50 S m-1 up to hypertonic solutions of conductivity of 2.02 S m-1 at selected temperatures of 25°C (standard benchmark temperature) and 37°C (physiological temperature). In isotonic solutions, cytoplasmic conductivity of human erythrocyte decreases with rise in the external media ionic concentration and vice versa for hypertonic solutions. The HRBC is capable of rapidly regulating its volume (and shape) over quite a wide range of osmolality. Specific Absorption Rate (SAR, 900 MHz) values (W kg-1) of electromagnetic radiation are below safe limits at non-physiological 25°C but above legal limits at 37°C [National Council on Radiation Protection and Measurements, NCRP]. However, at 37°C under both hypertonic [Na+] and isotonic but low [Na+], SAR increases further beyond legal limits.
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26

Garcia, Maíra M., Tiago R. Oliveira, Khallil T. Chaim, et al. "Thermal measurements of a muscle-mimicking phantom during ultra-high field magnetic resonance imaging." Current Directions in Biomedical Engineering 9, no. 1 (2023): 319–22. http://dx.doi.org/10.1515/cdbme-2023-1080.

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Abstract At ultra-high field MRI (Bo&gt;7T) it is crucial to predict and control the patient safety. Commonly patient safety is controlled by the power deposited in the tissue (specific absorption rate - SAR). However, temperature distributions do not always correlate directly with SAR distributions, which makes temperature control also a crucial parameter to guarantee patient safety. In this work, temperature changes were accessed by MR thermometry, specifically by the proton resonance frequency shift technique (PRF). A phantom mimicking muscle tissue was used to evaluate the temperature rise caused by the radiofrequency (RF) absorption during 7T MRI, applied through a commercial birdcage head coil. A pulse-sequence protocol was implemented for both, the generation of temperature increase and the MR thermometry. To control the temperature, a digital thermometer was used, and oil tubes were utilized to dismiss the drift effects for PRF. Measurements of the phantom’s dielectric characteristics, i.e. conductivity and permittivity, were in good agreement with the literature values for muscle. Spatio-temporal evaluations showed a temperature increase in time via RF exposure and the feasibility of measuring temperature maps using the PRF shift method. The accuracy of the PRF shift method increased when the drift effects were quantified and dismissed, indicating a PRF reading accuracy differing less than 0.5 °C from the thermometer. Results also validate our heating and temperature imaging protocol. This study is a valuable contribution to the evaluation of heating effects caused by RF absorption and demonstrates potential impact on future thermal investigations, which may use different heating sources, as well validate thermal simulations.
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27

Lim, Seonho, and Young Joong Yoon. "Phase Compensation Technique for Effective Heat Focusing in Microwave Hyperthermia Systems." Applied Sciences 11, no. 13 (2021): 5972. http://dx.doi.org/10.3390/app11135972.

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In this paper, effective electromagnetic (EM) focusing achieved with a phase compensation technique for microwave hyperthermia systems is proposed. To treat tumor cells positioned deep inside a human female breast, EM energy must be properly focused on the target area. A circular antenna array for microwave hyperthermia allows EM energy to concentrate on a specific target inside the breast tumor. Depending on the cancerous cell conditions in the breast, the input phases of each antenna are calculated for single and multiple tumor cell locations. In the case of multifocal breast cancer, sub-array beam focusing via the phase compensation technique is presented to enhance the ability of EM energy to concentrate on multiple targets while minimizing damage to normal cells. To demonstrate the thermal treatment effects on single and multiple tumor locations, the accumulation of the specific absorption rate (SAR) parameter and temperature changes were verified using both simulated and experimental results.
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28

Singh, Rakesh, Naina Narang, Dharmendra Singh, and Manoj Gupta. "Compact Wideband Microstrip Patch Antenna Design for Breast Cancer Detection." Defence Science Journal 71, no. 03 (2021): 352–58. http://dx.doi.org/10.14429/dsj.71.16704.

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The current breast cancer detection techniques are mostly invasive and suffer from high cost, high false rate and inefficacy in early detection. These limitations can be subdued by development of non-invasive microwave detection system whose performance is predominantly dependent on the antenna used in the system. The designing of a compact wideband antenna and matching its impedance with breast phantom is a challenging task. In this paper, we have designed a compact antenna matched with the breast phantom operating in wideband frequency from 1 to 6 GHz capable to detect the dielectric (or impedance) contrast of the benign and malignant tissue. The impedance of the antenna is matched to a cubically shaped breast phantom and a very small tumor (volume=1 cm3). The antenna is tuned to the possible range of electrical properties of breast phantom and tumour (permittivity ranging from 10 to 20 and conductivity from 1.5 to 2.5 S/m). The return loss (S11), E-field distribution and specific absorption rate (SAR) are simulated. The operating band of antenna placed near the phantom without tumor was found to be (1.11-5.47)GHz and with tumor inside phantom is (1.29-5.50)GHz. Results also show that the SAR of the antenna is within the safety limit.
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29

HEYDARI, MORTEZA, MEHRDAD JAVIDI, MOHAMMAD MAHDI ATTAR, et al. "MAGNETIC FLUID HYPERTHERMIA IN A CYLINDRICAL GEL CONTAINS WATER FLOW." Journal of Mechanics in Medicine and Biology 15, no. 05 (2015): 1550088. http://dx.doi.org/10.1142/s0219519415500888.

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In magnetic fluid hyperthermia (MFH), nanoparticles are injected into a diseased tissue and then subjected to an alternating high frequency magnetic field. The produced heat may have a key asset to destroy the cancerous cells. The blood flow in a tissue is considered as the most complicated part of the MFH which should be taken into account in the analysis of the MFH. This study was aimed to perform an experimental study to investigate the heat transfer of agar gel which contains fluid flow. Fe 3 O 4 as a nanoparticle was injected into the center of a cylindrical gel. It was also embedded with other cylindrical gels and subjected to an alternating magnetic field of 7.3 (kA/m) and a frequency of 50 (kHz) for 3600 (s). The temperature of the gel was measured at three points. The temperature distribution was measured via the experimental data. Moreover, specific absorption rate (SAR) was quantified with time differential temperature function at t = 0 by means of experimental data. Finite element method (FEM) was employed to establish a model to validate the SAR function. Results revealed the effects of fluid flow and accuracy of the SAR function for heat production in gel. The proposed function have implications in hyperthermia studies as a heat generation source. Finally, the condition of experimental setup was simulated to find the blood perfusion.
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30

Nor, Hadzfizah Mohd Radi, Muzafar Ismail Mohd, Zakaria Zahriladha, Abd Razak Jeefferie, and Nur Illia Abdullah Siti. "Development and design of wearable textile antenna on various fabric substrate for unlicensed ultra-wideband applications." TELKOMNIKA (Telecommunication, Computing, Electronics and Control) 20, no. 6 (2022): 1181–88. https://doi.org/10.12928/telkomnika.v20i6.23356.

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In the area of wearable technology an enhancement of basic microstrip antenna is evolution of wearable textile antenna. A major requirement for wearable textile antenna is its flexible designed materials which incoprates of fabric in the structure. The parameters obtained from the wearable textile antenna are return loss (S-11), directivity, gain, voltage standing wave ratio (VSWR) as well as the specific absorption rate (SAR) value. All these parameters are mostly influenced by the value of substrate dielectric constant and its thickness. In this paper, the design of wearable dual band frequency microstrip antenna is presented for wireless communication services. When the federal communication commission (FSS) has allowed the operation of unlicensed ultra-wideband (UWB) thus it attracted research interest in realizing UWB antennas for wireless applications. The operating frequency of the proposed antenna ranges from 2.85 GHz to 7.3 GHz. For body-worn and wearable applications, the antenna is embedded on selected textiles (i.e. felt, denim, polyester and leather). The prorposed microstrip antenna is designed, simulated and analysed in computer simulation technology (CST) microwave studio.
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31

Fantechi, Elvira, Paula M. Castillo, Erika Conca, Francesca Cugia, Claudio Sangregorio, and Maria Francesca Casula. "Assessing the hyperthermic properties of magnetic heterostructures: the case of gold–iron oxide composites." Interface Focus 6, no. 6 (2016): 20160058. http://dx.doi.org/10.1098/rsfs.2016.0058.

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Gold–iron oxide composites were obtained by in situ reduction of an Au(III) precursor by an organic reductant (either potassium citrate or tiopronin) in a dispersion of preformed iron oxide ultrasmall magnetic (USM) nanoparticles. X-ray diffraction, transmission electron microscopy, chemical analysis and mid-infrared spectroscopy show the successful deposition of gold domains on the preformed magnetic nanoparticles, and the occurrence of either citrate or tiopronin as surface coating. The potential of the USM@Au nanoheterostructures as heat mediators for therapy through magnetic fluid hyperthermia was determined by calorimetric measurements under sample irradiation by an alternating magnetic field with intensity and frequency within the safe values for biomedical use. The USM@Au composites showed to be active heat mediators for magnetic fluid hyperthermia, leading to a rapid increase in temperature under exposure to an alternating magnetic field even under the very mild experimental conditions adopted, and their potential was assessed by determining their specific absorption rate (SAR) and compared with the pure iron oxide nanoparticles. Calorimetric investigation of the synthesized nanostructures enabled us to point out the effect of different experimental conditions on the SAR value, which is to date the parameter used for the assessment of the hyperthermic efficiency.
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32

Manikandan, M., and S. Karthigai Lakshmi. "A Compact Penta-Band Low-SAR Antenna Loaded with Split-Ring Resonator for Mobile Applications." International Journal of Antennas and Propagation 2022 (December 30, 2022): 1–12. http://dx.doi.org/10.1155/2022/3298866.

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A compact rectangular patch with dual-ring SRR (split-ring resonator) is presented in this article. An antenna is designed on FR4 substrate with an overall footprint size of 26 mm × 30 mm × 1.6 mm. The antenna presented operates in five bands from 2.95 to 3.06 GHz, 3.79 to 3.87 GHz, 4.11 to 4.19 GHz, 5.39 to 5.51 GHz, and 5.97 to 6.11 GHz. Mobile and fixed voice communication, WiMAX (Worldwide Interoperability for Microwave Access), 5G (5th generation), WLAN (Wireless Local Area Network), and ISM (Industrial Scientific and Medical) are some applications that utilized the above resonating bands. The penta-band operation is due to the inclusion of dual-ring SRR. The optimum values of the critical parameter of the SRR are identified using parametric analysis, and the results are presented. The antenna is also analyzed for the SAR (specific absorption rate) values, and it was found to be less than 2 W/kg for 10 g volume of tissue. The designed antenna is fabricated and tested, and the presented results show that there is good agreement between the simulated and measured results. Penta-band operation with simple structure, stable radiation pattern, and low SAR makes this antenna more intelligent and suitable for the mobile application.
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33

Moacă, Elena-Alina, Vlad Socoliuc, Dana Stoian, et al. "Synthesis and Characterization of Bioactive Magnetic Nanoparticles from the Perspective of Hyperthermia Applications." Magnetochemistry 8, no. 11 (2022): 145. http://dx.doi.org/10.3390/magnetochemistry8110145.

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Magnetic iron oxide nanoparticles were obtained for the first time via the green chemistry approach, starting from two aqueous extracts of wormwood (Artemisia absinthium L.), both leaf and stems. In order to obtain magnetic nanoparticles suitable for medical purposes, more precisely with hyperthermia inducing features, a synthesis reaction was conducted, both at room temperature (25 °C) and at 80 °C, and with two formulations of the precipitation agent. Both the quality and stability of the synthesized magnetic iron oxide nanoparticles were physiochemically characterized: phase composition (X-ray powder diffraction (XRD)), thermal behavior (thermogravimetry (TG) and differential scanning calorimetry (DSC)), electron microscopy (scanning (SEM) and transmission (TEM)), and magnetic properties (DC and HF-AC). The magnetic investigation of the as-obtained magnetic iron oxide nanoparticles revealed that the synthesis at 80 °C using a mixture of NaOH and NH3(aq) increases their diameter and implicitly enhances their specific absorption rate (SAR), a mandatory parameter for practical applications in hyperthermia.
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34

Ali, Shirook M., Huanhuan Gu, Kelce Wilson, and James Warden. "Improved Handset Antenna Performance via an Electrically Extended Ground Plane." ISRN Communications and Networking 2012 (March 25, 2012): 1–7. http://dx.doi.org/10.5402/2012/621526.

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A novel and practical approach is presented providing improved antenna performance without enlarging the antenna or the ground plane. The approach electrically extends the ground plane using wire(s) that behave as surface metal extensions of the ground plane. The wire extensions can be accommodated within typical handset housing or as part of the stylish metal used on the handset’s exterior perimeter; hence don’t require enlargement of the device. Consequently, this approach avoids the costs and limitations traditionally associated with physically lengthening of a ground plane. Eight variations are presented and compared with baseline antenna performance. Both far-field patterns and near-field electromagnetic scans demonstrate that the proposed approach controls the electrical length of the ground plane and hence its chassis wavemodes, without negatively impacting the characteristics of the antenna. Improvements in performance of up to 56% in bandwidth at 900 MHz and up to 12% in efficiency with a reduction of up to 12% in the specific absorption rate (SAR) are achieved. An 8% increase in efficiency with a 1.3% improvement in bandwidth and a 20% reduction in SAR is achieved at 1880 MHz. Thus, improvements in bandwidth are achieved without compromising efficiency. Further, improvements at lower frequencies do not compromise performance at higher frequencies.
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35

Wu, Rigeng, Jian Dong, and Meng Wang. "Wearable Polarization Conversion Metasurface MIMO Antenna for Biomedical Applications in 5 GHz WBAN." Biosensors 13, no. 1 (2023): 73. http://dx.doi.org/10.3390/bios13010073.

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This paper presents a wearable metasurface multiple-input multiple-output (MIMO) antenna for biomedical applications in a 5 GHz wireless body area network (WBAN) with broadband, circular polarization (CP), and high gain. The physical properties of the MIMO antenna element and the principles of polarization conversion are analyzed in-depth using characteristic mode analysis. For the proposed MIMO antenna, the measured −10 dB impedance bandwidth is 34.87% (4.76–6.77 GHz), and the 3 dB axial ratio bandwidth is 22.94% (4.9–6.17 GHz). By adding an isolation strip, the measured isolation of the two antenna elements is greater than 19.85 dB. The overall size of the MIMO antenna is 1.67λ0 × 0.81λ0 × 0.07λ0 at 5.6 GHz, and the maximum gain is 7.95 dBic. The envelope correlation coefficient (ECC) is less than 0.007, with the maximum diversity gain greater than 9.98 dB, and the channel capacity loss is less than 0.29 b/s/Hz. The specific absorption rate (SAR) of the wearable MIMO antenna is simulated by the human tissue model, which proves that the proposed antenna conforms to international standards and is harmless to humans. The proposed wearable metasurface MIMO antenna has CP, broadband, high gain, low ECC, and low SAR, which can be used in wearable devices for biomedical applications.
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36

Midura, Mateusz, Waldemar T. Smolik, Przemysław Wróblewski, et al. "The Lumped-Parameter Calorimetric Model of an AC Magnetometer Designed to Measure the Heating of Magnetic Nanoparticles." Applied Sciences 15, no. 6 (2025): 3199. https://doi.org/10.3390/app15063199.

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The assessment of superparamagnetic nanoparticle heating is crucial for effective hyperthermia. AC magnetometry can be used to determine the specific absorption rate (SAR) of nanoparticles, assuming proper calorimetric calibration. We show that an AC magnetometer developed in our laboratory can be used simultaneously as a calorimeter for calibrating measurements. An electrical circuit with lumped parameters that are equivalent to the non-adiabatic calorimeter and that incorporates the effects of heat flow from the excitation coil, the surrounding environment, and the sample is presented. Quantitative thermal system identification was performed using global optimization, which fitted the temperature measured by the three fiber-optic probes to the simulated temperature transient curves. The identified model was used to estimate the thermal power generated in the measurement sample using a resistor with a controlled current value. The results demonstrate significant error reduction, particularly at lower heating powers, where external heat transfer becomes more influential. At low heating power values (around 25 mW), the error was reduced from 16.09% to 2.36%, with less pronounced improvements at higher power levels. The model achieved an overall accuracy of less than 2.5% across the 20–200 mW calibration range, a substantial improvement over the corrected-slope method. The value of the true thermal power of nanoparticles can be obtained using the calibrated calorimeter.
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37

Govindan, Thennarasi, Sandeep Kumar Palaniswamy, Malathi Kanagasabai, and Sachin Kumar. "Design and Analysis of UWB MIMO Antenna for Smart Fabric Communications." International Journal of Antennas and Propagation 2022 (December 21, 2022): 1–14. http://dx.doi.org/10.1155/2022/5307430.

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This paper presents a flexible multiple-input, multiple-output (MIMO) antenna with ultrawideband (UWB) performance for smart clothing applications. The MIMO antenna is comprised of four octagonal-shaped radiators with several slots loaded into them, and it offers a frequency range of 2.9–12 GHz. The unit cell has a size of 0.26λ0 × 0.164λ0 × 0.014λ0 and the MIMO antenna has a size of 0.48λ0 × 0.48λ0 × 0.014λ0, where λ0 corresponds to the lowest operating frequency. The radiation and diversity performances of the antenna are evaluated, and the obtained metrics are envelope correlation coefficient (ECC) &lt;0.045, diversity gain (DG) &gt;9.9 dB, total active reflection coefficient (TARC) &lt;−14 dB, and channel capacity loss (CCL) &lt;0.13 bits/s/Hz. The bending analysis of the MIMO antenna is performed. The specific absorption rate (SAR) of the MIMO antenna is also investigated, and the obtained values are 0.229 W/Kg (4 GHz), 0.253 W/Kg (7 GHz), and 0.463 W/Kg (10 GHz).
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38

Amdaouch, Ibtisam, Mohamed Saban, Jaouad El Gueri, et al. "A Novel Approach of a Low-Cost UWB Microwave Imaging System with High Resolution Based on SAR and a New Fast Reconstruction Algorithm for Early-Stage Breast Cancer Detection." Journal of Imaging 8, no. 10 (2022): 264. http://dx.doi.org/10.3390/jimaging8100264.

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In this article, a new efficient and robust approach—the high-resolution microwave imaging system—for early breast cancer diagnosis is presented. The core concept of the proposed approach is to employ a combination of a newly proposed delay-and-sum (DAS) algorithm and the specific absorption rate (SAR) parameter to provide high image quality of breast tumors, along with fast image processing. The new algorithm enhances the tumor response by altering the parameter referring to the distance between the antenna and the tumor in the conventional DAS matrices. This adjustment entails a much clearer reconstructed image with short processing time. To achieve these aims, a high directional Vivaldi antenna is applied around a simulated hemispherical breast model with an embedded tumor. The detection of the tumor is carried out by calculating the maximum value of SAR inside the breast model. Consequently, the antenna position is relocated near the tumor region and is moved to nine positions in a trajectory path, leading to a shorter propagation distance in the image-creation process . At each position, the breast model is illuminated with short pulses of low power waves, and the back-scattered signals are recorded to produce a two-dimensional image of the scanned breast. Several simulations of testing scenarios for reconstruction imaging are investigated. These simulations involve different tumor sizes and materials. The influence of the number of antennas on the reconstructed images is also examined. Compared with the results from the conventional DAS, the proposed technique significantly improves the quality of the reconstructed images, and it detects and localizes the cancer inside the breast with high quality in a fast computing time, employing fewer antennas.
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39

Al- Faruk, Abdullah, and Rinku Basak. "A Novel Design and Performance Analysis of an ISM Band Antenna for Biomedical Applications." AIUB Journal of Science and Engineering (AJSE) 17, no. 3 (2018): 75–82. http://dx.doi.org/10.53799/ajse.v17i3.12.

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Biomedical application is an advancing sector of research work which permits the development of a transmission link from a living body to an extrinsic device. A microstrip patch antenna is proposed in this paper for biomedical applications. The antenna is designed to operate in the Industrial, Scientific and Medical (ISM) band (2.4 – 2.4835 GHz). The thickness of the antenna is only 2.3 mm which implies that the antenna is reliable to operate under bent conditions. The dimension of the proposed antenna is 28.5 mm x 28.5 mm x 2.3 mm. In this antenna, Copper is used as the patch material and FR-4 is used as the substrate material. Three-layer human tissue model is used to analysis the performance of the antenna. Computer Simulation Technology (CST) software is used to designed the antenna and analysis the performance parameter of the antenna such as the return loss (S11 parameter), radiation pattern, operating frequency, directivity, gain, total efficiency under normal and bent conditions on the human tissue model. Performance analysis is also observed for different substrate material, different patch material, and different types of human tissues and comparison analysis of S11 parameter for the planar and bent condition. Among all of the substrate materials, FR4 provides the good antenna performance. Finally, Specific Absorption Rate (SAR) and thermal loss are evaluated to comply with the antenna safety issues.
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40

Goswami, Niloy, and Md Abdur Rahman. "A 9.73 GHz wide-band off-body patch antenna for biomedical applications." Indonesian Journal of Electrical Engineering and Computer Science 33, no. 1 (2024): 151. http://dx.doi.org/10.11591/ijeecs.v33.i1.pp151-158.

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&lt;span&gt;The primary goal of this study is to design a simple antenna that has a wide bandwidth and low return loss for biomedical applications. The paper shows the recommended antenna’s three-stage modeling, with the goal of assessing every important parameter while a Teflon or polytetrafluoroethylene (PTFE) polymer substrate is used. In order to better comprehend, a comparison with prior studies employing teflon and similar substrate materials is conducted for the proposed patch antenna. The analysis includes the phantom model, evaluating performance criteria such as specific absorption rate (SAR), return loss, bandwidth, and gain values relevant to biomedical applications. The antenna works at two different frequencies: 9.73 and 9.39 GHz, one in free space and another in a skin-cotton layer. The bandwidth of the antenna is 4.067 GHz in free space at the resonance frequency of 9.73 GHz, where the return loss is -62.18 dB. The performance of the proposed antenna in the field of biomedical applications, its underlying reasons, and its impacts are discussed in detail in this study.&lt;/span&gt;
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41

Wang, Runsheng, Jianheng Liu, Yihao Liu, et al. "The cell uptake properties and hyperthermia performance of Zn 0.5 Fe 2.5 O 4 /SiO 2 nanoparticles as magnetic hyperthermia agents." Royal Society Open Science 7, no. 1 (2020): 191139. http://dx.doi.org/10.1098/rsos.191139.

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Zn 0.5 Fe 2.5 O 4 nanoparticles (NPs) of 22 nm are synthesized by a one-pot approach and coated with silica for magnetic hyperthermia agents. The NPs exhibit superparamagnetic characteristics, high-specific absorption rate (SAR) (1083 wg −1 , f = 430 kHz, H = 27 kAm −1 ), large saturation magnetization ( M s = 85 emu g −1 ), excellent colloidal stability and low cytotoxicity. The cell uptake properties have been investigated by Prussian blue staining, transmission electron microscopy and the inductively coupled plasma-mass spectrometer, which resulted in time-dependent and concentration-dependent internalization. The internalization appeared between 0.5 and 2 h, the NPs were mainly located in the lysosomes and kept in good dispersion after incubation with human osteosarcoma MG-63 cells. Then, the relationship between cell uptake and magnetic hyperthermia performance was studied. Our results show that the hyperthermia efficiency was related to the amount of internalized NPs in the tumour cells, which was dependent on the concentration and incubation time. Interestingly, the NPs could still induce tumour cells to apoptosis/necrosis when extracellular NPs were rinsed, but the cell kill efficiency was lower than that of any rinse group, which indicated that local temperature rise was the main factor that induced tumour cells to death. Our findings suggest that this high SAR and biocompatible silica-coated Zn 0.5 Fe 2. O 4 NPs could serve as new agents for magnetic hyperthermia.
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42

Ali, Waqas, N. Nizam-Uddin, Wazie M. Abdulkawi, et al. "Design and Analysis of a Quad-Band Antenna for IoT and Wearable RFID Applications." Electronics 13, no. 4 (2024): 700. http://dx.doi.org/10.3390/electronics13040700.

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The role of antennas in wireless communication is critical for enabling efficient signal transmission and reception across various frequency bands, including those associated with IoT (Internet of Things), X-band, S-band, and RFID (radio-frequency identification) systems. This paper presents a small quadruple-band antenna with 25 × 40 × 1.5 mm3 dimensions designed for diverse wireless applications. It is adept at operating in the S-band (2.2 GHz), wireless local area network (WLAN) (5.7 GHz), microwave RFID frequency band (5.8 GHz), and X-band (7.7 GHz and 8.3 GHz). While the majority of existing research focuses on antennas covering two or three bands, our work stands out by achieving quad-band operation in the proposed antenna design. This antenna is constructed on a semiflexible Rogers RT5880 substrate, making it well-suited for wearable applications. Computer Simulation Technology (CST) Microwave studio (2019) simulation package software is chosen for design and analysis. The antenna design features a comb-shaped radiating structure, where each “tooth” is responsible for resonating at a distinct frequency with an appropriate bandwidth. The antenna retains stability in both free space and on-body wearability scenarios. It achieves a low specific absorption rate (SAR), meeting wearable criteria with SAR values below 1.6 W/Kg for all resonating frequencies. The proposed antenna demonstrates suitable radiation efficiency, reaching a maximum of 82.6% and a peak gain of 6.3 dBi. It exhibits a bidirectional pattern in the elevation plane and omnidirectional behavior in the azimuth plane. The antenna finds applications across multiple frequencies and shows close agreement between simulated and measured results, validating its effectiveness.
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43

Kozenkova, Elena, Kateryna Levada, Maria V. Efremova, et al. "Multifunctional Fe3O4-Au Nanoparticles for the MRI Diagnosis and Potential Treatment of Liver Cancer." Nanomaterials 10, no. 9 (2020): 1646. http://dx.doi.org/10.3390/nano10091646.

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Heterodimeric nanoparticles comprising materials with different functionalities are of great interest for fundamental research and biomedical/industrial applications. In this work, Fe3O4-Au nano-heterostructures were synthesized by a one-step thermal decomposition method. The hybrid nanoparticles comprise a highly crystalline 12 nm magnetite octahedron decorated with a single noble metal sphere of 6 nm diameter. Detailed analysis of the nanoparticles was performed by UV-visible spectroscopy, magnetometry, calorimetry and relaxometry studies. The cytotoxic effect of the nanoparticles in the human hepatic cell line Huh7 and PLC/PRF/5-Alexander was also assessed. These Fe3O4-Au bifunctional nanoparticles showed no significant cytotoxicity in these two cell lines. The nanoparticles showed a good theranostic potential for liver cancer treatment, since the r2 relaxivity (166.5 mM−1·s−1 and 99.5 mM−1·s−1 in water and HepG2 cells, respectively) is higher than the corresponding values for commercial T2 contrast agents and the Specific Absorption Rate (SAR) value obtained (227 W/gFe) is enough to make them suitable as heat mediators for Magnetic Fluid Hyperthermia. The gold counterpart can further allow the conjugation with different biomolecules and the optical sensing.
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44

Andrade, Raquel G. D., Débora Ferreira, Sérgio R. S. Veloso, et al. "Synthesis and Cytotoxicity Assessment of Citrate-Coated Calcium and Manganese Ferrite Nanoparticles for Magnetic Hyperthermia." Pharmaceutics 14, no. 12 (2022): 2694. http://dx.doi.org/10.3390/pharmaceutics14122694.

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Calcium-doped manganese ferrite nanoparticles (NPs) are gaining special interest in the biomedical field due to their lower cytotoxicity compared with other ferrites, and the fact that they have improved magnetic properties. Magnetic hyperthermia (MH) is an alternative cancer treatment, in which magnetic nanoparticles promote local heating that can lead to the apoptosis of cancer cells. In this work, manganese/calcium ferrite NPs coated with citrate (CaxMn1−xFe2O4 (x = 0, 0.2, 1), were synthesized by the sol-gel method, followed by calcination, and then characterized regarding their crystalline structure (by X-ray diffraction, XRD), size and shape (by Transmission Electron Microscopy, TEM), hydrodynamic size and zeta potential (by Dynamic Light Scattering, DLS), and heating efficiency (measuring the Specific Absorption Rate, SAR, and Intrinsic Loss Power, ILP) under an alternating magnetic field. The obtained NPs showed a particle size within the range of 10 nm to 20 nm (by TEM) with a spherical or cubic shape. Ca0.2Mn0.8Fe2O4 NPs exhibited the highest SAR value of 36.3 W/g at the lowest field frequency tested, and achieved a temperature variation of ~7 °C in 120 s, meaning that these NPs are suitable magnetic hyperthermia agents. In vitro cellular internalization and cytotoxicity experiments, performed using the human cell line HEK 293T, confirmed cytocompatibility over 0–250 µg/mL range and successful internalization after 24 h. Based on these studies, our data suggest that these manganese-calcium ferrite NPs have potential for MH application and further use in in vivo systems.
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45

Mahendra, Daffa, Randy Ivanal Hakim, and Endarko Endarko. "Design of Antipodal Vivaldi Antenna for Medical Imaging Application." Jurnal Penelitian Fisika dan Aplikasinya (JPFA) 13, no. 2 (2023): 132–45. http://dx.doi.org/10.26740/jpfa.v13n2.p132-145.

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The microwave imaging (MWI) system in medical applications is commonly used to detect abnormalities in the human body. The purpose of this study was to design an Antipodal Vivaldi Antenna (AVA) for medical imaging applications using MWI. The research method used is based on the AVA design simulation of the CST Studio Suite 2019 application using time and frequency domain methods, which has dimensions of 60x40 mm2 with an antenna structure that works in the frequency range of 6.3-9.6 GHz, the impedance for bandwidth is -10 dB, using Flame Retardant-4 (FR-4) thickness 1.6 mm (= 4.3, tan δ = 0.025) as substrate material. A linear array of antennas was utilized in the simulation, either with or without a phantom. The phantom options include an absence of a phantom (only antennas), a cube-shaped water phantom, and a water phantom containing an anomaly. The result of the simulation on the AVA design produces a bandwidth of 41.61%, a gain of 5.16 dB, a return loss of -26.73 dB, a Specific Absorption Rate (SAR) value of 0.26 W/kg and a graph of S-parameters (S21). It can be concluded that the MWI system using the AVA design in this study has the potential to properly detect the presence of anomalies.
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46

Sultana, Sadia, and Rinku Basak. "Performance Evaluation of Meander Line Implantable Antenna integrated with EBG Based Ground for Anatomical Realistic Model." AIUB Journal of Science and Engineering (AJSE) 18, no. 1 (2019): 1–10. http://dx.doi.org/10.53799/ajse.v18i1.16.

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A unique design and meander line implantable antenna is examined in this paper which satisfies the requirements of ultra-wide band. The designed antenna is integrated with the electromagnetic band gap (EBG) structure based ground plane to enhance the performance. Rectangular electromagnetic band gap (EBG) structures are represented here to evaluate the antenna performance. This compact and efficient MLA antenna is applied to improve the antenna performance for numerous implantable scenarios and biomedical applications. The proposed antenna with EGB ground plane is designed for both the simplified model and anatomical realistic models for the human body and executed the performance in bio-environment. To approve the results of implantable antennas more correctly, simulation is analyzed using anatomical realistic human models. The ultimate design has the whole dimension is 15.2 x 8.8 m2. The thickness of the antenna is about 0.8 mm. FR4 is chosen as the substrate material and Copper is chosen as the patch material. The antenna is enclosed biocompatible material with silicon inside the tissue in order to protect patient safety. Significant parameters such as S11 parameter, Far field (radiation pattern), VSWR, Efficiency, Directivity, Gain of the proposed antenna have calculated and measured the performance both the simplified and realistic human models. Comparison Analysis of S11 parameter for different substrate materials and patch materials have observed. The radiation mechanism and modified design of the implantable antenna reducing Specific Absorption Rate (SAR) for safety issues. All the simulation results and measurements are obtained from CST Microwave Studio to validate the design.
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47

Stankovic, Vladimir, Dejan Jovanovic, Dejan Krstic, Vera Markovic, and Momir Dunjic. "Calculation of electromagnetic field from mobile phone induced in the pituitary gland of children head model." Vojnosanitetski pregled 74, no. 9 (2017): 854–61. http://dx.doi.org/10.2298/vsp151130279s.

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Background/Aim. A mobile phone is a source of electromagnetic radiation located close to the head and consequently its intense use may cause harmful effects particularly in younger population. The aim of this study was to investigate the influence of electromagnetic field of the mobile phone on the pituitary gland of the child. Methods. In order to obtain the more accurate results for this research 3D realistic model of child's head whose size corresponds to an average child (7 years old) was created. Electric field distribution in child head model and values of Specific Absorption Rate (SAR) at the region of pituitary gland were determined. This study was performed for the frequencies of 900 MHz, 1800 MHz, and 2100 MHz, as the most commonly used in mobile communications. The special attention was dedicated to the values of the electric field and the values of the SAR in the pituitary gland. For all frequencies over 10 g and 1 g of tissue average SAR was calculated. The electric field distribution and values of average SAR for 10 g and 1 g trough the model of child's head were obtained by the using numerical calculation based on the Finite Integration Technique (FIT). Results. The largest value of electric field in the region of the pituitary gland was at the frequency of 900 MHz, as a consequence of the highest penetration depth. Lower values of the electric field in the region of the pituitary gland were at frequencies of 1,800 MHz and 2,100 MHz. The SAR in the pituitary gland decreased as the frequency increased as a direct consequence of lower penetration depth. Conclusion. The electric field strength from a mobile phone is higher than the value specified by standards for the maximum allowable exposure limits. The high values of the electric field are not only in the vicinity of a mobile phone but also in tissues and organs of the human head. Particular attention should be paid to the exposure of children to radiation of mobile phones. Smaller dimensions of children?s head and smaller thickness of tissues and organs have as a consequence greater penetration of electromagnetic waves.
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48

Lemine, O. M., Saja Algessair, Nawal Madkhali, Basma Al-Najar, and Kheireddine El-Boubbou. "Assessing the Heat Generation and Self-Heating Mechanism of Superparamagnetic Fe3O4 Nanoparticles for Magnetic Hyperthermia Application: The Effects of Concentration, Frequency, and Magnetic Field." Nanomaterials 13, no. 3 (2023): 453. http://dx.doi.org/10.3390/nano13030453.

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Magnetite nanoparticles (MNPs) exhibit favorable heating responses under magnetic excitation, which makes them particularly suited for various hyperthermia applications. Herein, we report the detailed self-heating mechanisms of MNPs prepared via the Ko-precipitation Hydrolytic Basic (KHB) methodology. The as-prepared MNPs were fully characterized using various spectroscopic techniques including transmission electron microscopy (TEM), dynamic light scattering (DLS), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), and vibrating sample magnetometry (VSM). MNPs exhibited stable 15 nm quasi-spherical small-sized particles, pure crystalline cubic Fe3O4 phases, high saturation magnetizations (Ms = ~40 emu·g−1), and superparamagnetic behavior. In response to alternating magnetic fields (AMFs), these MNPs displayed excellent self-heating efficiencies with distinctive heating responses, even when minimal doses of MNPs were used. Heating efficacies and specific absorption rate (SAR) values as functions of concentration, frequency, and amplitude were systematically investigated. Remarkably, within only a few minutes, MNPs (2.5 mg/mL) showed a rapid dissipation of heat energy, giving a maximum intrinsic loss power (ILP) of 4.29 nHm2/kg and a SAR of 261 W/g. Hyperthermia temperatures were rapidly reached in as early as 3 min and could rise up to 80 °C. In addition, Rietveld refinement, Langevin, and linear response theory (LRT) models were studied to further assess the magnetic and heating mechanisms. The LRT model was used to determine the Néel relaxation time (τR = 5.41 × 10−7 s), which was compared to the Brownian relation time value (τR = 11 × 10−7 s), showing that both mechanisms are responsible for heat dissipated by the MNPs. Finally, the cytotoxicity assay was conducted on aqueous dispersions of MNPs, indicating their biocompatibility and low toxicity. Our results strongly suggest that the as-prepared Fe3O4 MNPs are promising vehicles for potential magnetically triggered biomedical hyperthermia applications.
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49

Rovin, Tiwari, Raghavendra Sharma Dr., and Rahul Dubey Dr. "A SURVEY ON UWB WEARABLE ANTENNA FOR BODY AREA NETWORK APPLICATION." INTERNATIONAL JOURNAL OF ENGINEERING TECHNOLOGIES AND MANAGEMENT RESEARCH 5, no. 2 :SE (2018): 274–80. https://doi.org/10.5281/zenodo.1203244.

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A body wearable antenna (BWA) is a hotly research issue for the examination. In this paper different kind of receiving antennas are displayed which are as of now accessible in writing. A BWA is a material receiving antenna, which is adaptable and comfort. At some point it isn&#39;t important that space accessible for mounting the receiving antenna is level, so radio antenna ought not to change its qualities amid twisting conditions. Save specialists for the most part work in such a domain which is disjoined by multipath, which cause the blurring of got flag. So to keep away from such kind of issue a multi energized reception apparatus may require. Besides when receiving antenna is put over the human body, because of bidirectional properties of radio antenna in reverse radiation may hurt the wearer&#39;s body. So to minimize such radiations EBG (Electromagnetic band gap) structures are utilized.
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50

M.M. Hasan Mahfuz, Md Rafiqul Islam, Norun Farihah Abdul Malek, Mohamed Hadi Habaebi, Nazmus Sakib, and Elham Baladi. "Wearable Textile Patch DSSRS Antenna for Body Tumors Detection with Reduced SAR." IIUM Engineering Journal 26, no. 1 (2025): 148–68. https://doi.org/10.31436/iiumej.v26i1.3221.

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The purpose of this study is to present a lightweight wearable (jeans) monopole antenna configuration for body area network (BAN) communication, breast and head tumors detections with back lobe reduction (i.e., low SAR), and it does so without introducing any special methodologies like as, AMC, EBG, HIS. The planned antenna has dual symmetrical slots as well as a ring-shaped slot (DSSRS) at the top, and it is in the form of a radiating rectangular patch with a ground plane. The design procedure has been finished with the help of CST MWS, and the next step will be to fine-tune the parameters of the antenna structure to achieve resonance at the ISM band (5.79 GHz). Testing for BAN, breast, and brain tumor detection was done using this prototype. With the proper impedance matching, the antenna achieves an operational bandwidth of 5.798 GHz (5.739–5.865 GHz), 5.77 GHz (5.715–5.838 GHz), 5.77 GHz (5.718–5.843 GHz) and 5.78 GHz (5.725–5.834 GHz), with an overall peak gain of 8.18 dBi, 7.69 dBi, 5.73 dBi, and 4.59 dBi; when proposed antenna placed on the free space, on the body, on the breast, and the head respectively. The suggested antenna meets the specific absorption rate (SAR) standards given by the FCC (1 gm) and the ICNIRP (10 gm). ABSTRAK: Kajian ini bertujuan untuk membentangkan konfigurasi antena monopole ringan boleh pakai (jenis jeans) untuk komunikasi rangkaian kawasan badan (BAN), pengesanan tumor payudara dan kepala dengan pengurangan lobus belakang (iaitu, SAR rendah), tanpa menggunakan metodologi khas seperti AMC, EBG, atau HIS. Antena yang dicadangkan mempunyai dua slot simetri (dual symmetrical slots) serta slot berbentuk cincin (DSSRS) di bahagian atas, dan berbentuk patch segi empat tepat yang memancar dengan satah tanah. Prosedur reka bentuk telah diselesaikan dengan bantuan perisian CST MWS, dan langkah seterusnya adalah untuk menyesuaikan parameter struktur antena bagi mencapai resonans pada jalur ISM (5.79 GHz). Ujian untuk BAN, pengesanan tumor payudara, dan tumor otak telah dijalankan menggunakan prototaip ini. Dengan padanan impedans yang betul, antena ini mencapai lebar jalur operasi sebanyak 5.798 GHz (5.739–5.865 GHz), 5.77 GHz (5.715–5.838 GHz), 5.77 GHz (5.718–5.843 GHz), dan 5.78 GHz (5.725–5.834 GHz), dengan pencapaian keuntungan puncak keseluruhan sebanyak 8.18 dBi, 7.69 dBi, 5.73 dBi, dan 4.59 dBi; apabila antena yang dicadangkan diletakkan di ruang bebas, pada badan, pada payudara, dan pada kepala masing-masing. Antena yang dicadangkan memenuhi piawaian kadar penyerapan spesifik (SAR) yang ditetapkan oleh FCC (1 gm) dan ICNIRP (10 gm)
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