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2023-12-25
PIER M
Vol. 122, 155-165, 2023
download: 81
An on-Chip Integrated Current Sensing Technology for Real-Time Detection of Phase Current in BLDC Motors
Jiayu Wen and Liangkun Wang
This paper presents an on-chip integrated sensing circuit for real-time detection of phase currents in three-phase brushless direct current (BLDC) motors. The three-phase sinusoidal currents generated in the motor winding are detected by an innovative Sense FET technology, which can accurately measure the currents of high-side P-type power transistors and low-side N-type power transistors simultaneously. A dynamic matching elimination method is proposed for the detection current mismatch problem due to the large difference in aspect ratio. Using a 90 nm dual-polarized cmos-DMOS (BCD) process for design and verification, the detection circuit of the high and low sides can well follow the change of sine wave phase current of the three-phase motor, and the accuracy is above 96%. The best accuracy can reach 99.219%. The elimination effect of circuit current mismatch is obvious, and the error of the sense current can be reduced by 38.9%.
An On-chip Integrated Current Sensing Technology for Real-time Detection of Phase Current in BLDC Motors
2023-12-25
PIER M
Vol. 122, 145-153, 2023
download: 79
Power Handling of Slot Loop Frequency Selective Surface Based on Approximate Analytical Method
Kang Luo , Jin Meng , Danni Zhu and Jiangfeng Han
In this paper, the power handling of a slot loop frequency selective surface based on approximate analytical method is proposed. The physical nature of the slot array periodic moment method is derived in detail. It is found that the left and right sides of periodic scatter matrix respectively represent the total tangential magnetic field acting on the left and right magnetic dipole arrays and moving in the direction of the reference array. According to the principle of equivalence, a slot array can be modeled by an array of magnetic currents on each side of the perfect electronic conductor. As a result, the total tangential magnetic field is zero in the sense of physical concept. Furthermore, a simple sinusoidal function is then used to approximate the magnetic current distribution along the slot loop which is similar to that of dipole antenna. By studying the corresponding zero points and extreme point of the magnetic current for the slot loop frequency selective surface element, the transmission coefficients and maximum electronic field are calculated. Examples of rectangle and triangle slot ring frequency selective surface have verified the efficiency and accuracy of the proposed method.
Power Handling of Slot Loop Frequency Selective Surface Based on Approximate Analytical Method
2023-12-22
PIER M
Vol. 122, 137-144, 2023
download: 78
Charging Current Characteristics and Effect of Casing Material in Wireless Recharging of Active Implantable Medical Devices Using Transcutaneous Energy Transfer System
Sarath S. Nair , Manivannan Muniyandi , Nagesh D S , Muraleedharan C V , Roy Joseph and Harikrishnan S
Batteries inside an active implantable medical device (AIMD) need to be replaced every few years. However, rechargeable batteries can enhance the life of such devices to a large extent. Transcutaneous Energy Transfer System (TETS) is a promising method for recharging these batteries inside medical devices. These devices are generally made of metal casings to avoid fluid ingress and provide better mechanical strength. However, the metal cases when being present in the path of electromagnetic energy induces eddy current thus producing excessive temperature rise due to thermal loss. Thus, the selection of an interface casing material plays a significant role in the performance of the wireless recharging. In this paper, the performance of a transcutaneous energy transfer system for recharging an AIMD with different axial gaps and casing materials is reported. The effect of these variations on the output voltage, recharge current, and efficiency of operation was quantified. It has been found that, with TETS the charging current of 0.3 A to 0.5 A can be obtained to charge the implanted battery within 180 minutes. It was found that the induced voltage in the secondary coil is substantially reduced with the presence of titanium casing compared to epoxy encapsulation. Thermal studies were performed with titanium casing material of various thicknesses. The casing temperature rose to above 70˚C within the first 10 minutes for 0.5 mm thickness and within 50 minutes in the case of 0.25 mm. With epoxy encapsulation, the casing temperature rose to only 30˚C. The charging voltage of 5 V and charging current of more than 0.3 A were obtained with epoxy encapsulation. A polymeric material casing or epoxy encapsulation is the best choice in the interface region to get a high recharging current in the case of wireless recharging of implantable medical devices. With the proposed design modification, wireless energy transfer and recharging implanted batteries shall be done in a more energy-efficient manner with less thermal damage to nearby tissues.
Charging Current Characteristics and Effect of Casing Material in Wireless Recharging of Active Implantable Medical Devices Using Transcutaneous Energy Transfer System
2023-12-19
PIER M
Vol. 122, 117-136, 2023
download: 183
Advances in Synthesis Strategies for Lanthanide-Based NaYF4 Upconversion Nanocrystals and Their Applications in Ratiometric Thermometry
Raheel Ahmed Janjua , Wenbin Ji , Nayyar Abbas Shah , Julian Evans , Ruili Zhang , Sheng Zhang and Sailing He
nullThe optical characteristics and varied applications of lanthanide-doped NaYF4 upconversion nanocrystals have received considerable interest in recent years, such as in ratiometric thermometry. This review thoroughly examines the various synthesis processes utilized in producing these nanocrystals and their application in temperature sensing. Synthesis of NaYF4 upconversion nanocrystals is a complex procedure that requires careful management of dopant concentrations, crystal phase, size, and shape. The distinctive luminescent characteristics of lanthanide ions, which facilitate the transformation of photons with low energy into emissions with higher energy, render NaYF4 nanocrystals very suitable for ratiometric thermometry applications. We explore the fundamental concepts underlying upconversion luminescence in developing ratio metric temperature sensors. In this discourse, we examine the selection of lanthanide dopants, the mechanics underlying their energy transmission, and the development of customized sensor architectures. This review covers the recent progress and utilization of NaYF4 upconversion nanocrystals in ratiometric thermometry, including diverse areas such as biological temperature detection, environmental surveillance, and material research. We evaluate the obstacles and potential advancements in this domain, specifically emphasizing approaches to improving temperature sensors' precision, responsiveness, and applicability based on upconversion.
Advances in Synthesis Strategies for Lanthanide-based NaYF4 Upconversion Nanocrystals and Their Applications in Ratiometric Thermometry
2023-12-19
PIER M
Vol. 122, 107-116, 2023
download: 134
Design of Spatial Magnetic Field Measurement System and Experimental Study of Near-Field Characteristics in Wireless Power Transfer System
Deyu Zeng , Jianwei Kang , Xiangyang Shi and Yang Shi
Magnetic coupling resonant wireless power transfer (WPT) technology is widely used in a lot of power equipment because of high efficiency and safety. Magnetic field is a key factor to study the energy transmission mechanism, transmission characteristics of WPT system. At present, the research on the WPT system spatial magnetic field mainly focuses on the theoretical research and finite element simulation, with relatively little experimental research. This paper aims to establish an experimental platform for the WPT system, propose and design a magnetic field measurement system suitable for a WPT system, and conduct experimental research on the WPT system magnetic field with the measurement system. The near field region of the magnetic field is divided, and the experimental magnetic field distribution law is obtained using dimensionless and surface fitting methods. Finally, different models are obtained by surface fitting to characterize the distribution law of the experimental magnetic field. The results indicate that the dimensionless magnetic field intensity follows different forms of exponential distribution in different regions. The models are in good agreement with the actual distribution of the magnetic field, which can effectively reflect the changes in actual magnetic field intensity.
Design of Spatial Magnetic Field Measurement System and Experimental Study of Near-field Characteristics in Wireless Power Transfer System
2023-12-15
PIER M
Vol. 122, 97-105, 2023
download: 92
Dispersion Analysis of a Planar Rectangular Tape Helix Slow Wave Structures Supported by Dielectric Rods
Naveen Babu and Nameesha Chauhan
The dispersion equation for a rectangular tape helix with four rectangular dielectric support rods has been deduced using precise boundary conditions employing field restricting functions. The dispersion equation is a much simplified conjoint expression obtained for axial and transverse directions derived by solving an infinite set of linear homogeneous simultaneous equations, represented as an infinite order matrix whose determinant is zero. Dispersion characteristics plotted from the simplified dispersion equation consist of the dominant and additional higher-order modes similar to an open rectangular slow wave structure (SWS), but with the existence of β0a(k0a) roots everywhere without the limitations of the forbidden region boundary. The phase velocity curves obtained for the corresponding mode of the dispersion characteristics exhibit comparable behavior to the free-space rectangular helix SWS, especially in the third ``allowed'' region, which offers a wider beam-wave interaction region with phase speed equivalent to the speed of light at higher operating frequencies. The numerically computed dispersion curves and their corresponding phase velocities were plotted. Similar dimensional variations of the structure with discrete support rods were simulated using three-dimensional simulation software. The dispersion characteristics obtained from the simplified dispersion equation along with the dimensional variation of the dielectric-loaded rectangular tape helix SWS determine the capability and limitations of such minuscule traveling wave tubes(TWTs) as planar TWTs suitable for fabrication using micro-machining techniques.
Dispersion Analysis of a Planar Rectangular Tape Helix Slow Wave Structures Supported by Dielectric Rods
2023-12-15
PIER M
Vol. 122, 85-95, 2023
download: 104
Innovative Loaded Low-Profile Tri-Band MIMO Antenna System for Wi-Fi 7 Technology
Ahmad Yacoub and Daniel N. Aloi
A distinctive low-profile 2x2 MIMO antenna system for Wi-Fi 7 applications is presented in this paper that is compact, easily manufactured and with excellent performance. Because of its compact size and good RF performance, the design can be placed in hidden locations for various applications such as the automotive field in the front side mirrors or front dashboard, and consumer products in laptops and internet wireless routers. The proposed design can cover the entire tri-bands of Wi-Fi 7 (2400-2495 MHz, 5150-5895 MHz, 5945-7125 MHz) using a loaded low-profile Planar Inverted-F Antenna (PIFA) with distinct dimensions and slots across its geometry. The element design and the MIMO system is simulated and a properly made prototype was fabricated to present the results in terms of reflection coefficients, current distribution, combined radiation patterns, passive isolation, ports efficiencies, and Envelope Correlation Coefficient (ECC). The design shows relatively good RF properties across the entire three bands, hence making it an attractive solution to be used for Wi-Fi 7 technology to satisfy the needs of larger omnidirectional coverage area, wider channel bandwidth, and better transmission rates with low interference.
Innovative Loaded Low-profile Tri-band MIMO Antenna System for Wi-Fi 7 Technology
2023-12-14
PIER M
Vol. 122, 73-83, 2023
download: 120
An Ultra-Wideband MIMO Antenna Based on Dual-Mode Transmission Line Feeding for Wireless Communication
Xianjing Lin , Gengtao Huang and Yao Zhang
An ultra-wideband (UWB) MIMO antenna based on dual mode transmission line feeding for wireless communication is proposed in this article. The general method of realizing a UWB MIMO antenna is using different shapes of monopoles acting as a MIMO antenna element, while the ultra-wideband character of the proposed MIMO antenna is mainly obtained by the use of a dual-mode transmission line in the coplanar waveguide (CPW) feeding line, which offers a novel method. The proposed MIMO antenna element is a rose-shaped monopole fed by a CPW feeding line. Compared to the traditional monopole, a rose-shaped monopole can introduce several extra resonant frequencies, and the impedance bandwidth can be improved. Besides, a dual-mode transmission line (DMTL) is introduced by adding specific stubs to the CPW feeding line. Arranging the stubs at the half wavelengths of the desired frequencies, mode transformation can be accomplished, and additional resonant modes can be generated. As a result, the impedance bandwidth can be further broadened. Results show that the fractional impedance bandwidth of the proposed UWB antenna element is 165.5% (2.59 GHz to 26.61 GHz). Then, the UWB antenna is applied to design a 4-element MIMO antenna. By loading four u-typed decoupling structures at the center of the MIMO antenna, the port-to-port isolation of the MIMO antenna can be increased to 20 dB within a wide bandwidth, especially 25.3 dB at the higher band (14-25 GHz). The proposed UWB MIMO antenna is manufactured and tested. Experimental results show that the impedance bandwidth covers 2.40 GHz to 25 GHz (165%). The diversity gain (DG) of the antenna in the operating band is about 10; the envelope correlation coefficient (ECC) is less than 0.002; and the radiation efficiency ranges from 85% to 95% in the whole working band. The design is a preferable candidate for MIMO systems.
An Ultra-wideband MIMO Antenna Based on Dual-mode Transmission Line Feeding for Wireless Communication
2023-12-13
PIER M
Vol. 122, 63-72, 2023
download: 96
Non-Singular Fast Terminal Sliding Mode Control Torsional Vibration Suppression for PM Synchronous Transmission System of EVs
Ning Jia , Kaihui Zhao , Yuying Lv and Xiangfei Li
To suppress the torsional vibration caused by the omission of couplings and dampers during flexible power transmission in the permanent magnet (PM) synchronous drive system of pure electric vehicles (EVs), this paper presents a non-singular fast terminal sliding mode control (NFTSMC) torsional vibration suppression strategy based on a sliding mode disturbance observer (SMDO). First, a PM synchronous drive system is simplified as a two-inertia model, and a mathematical model is established. Then, an NFTSMC controller of the load-side speed feedback is designed to suppress torsional vibration. Meanwhile, an SMDO is designed to estimate the load disturbance, and the estimated value is fed back to the controller to perform feedforward compensation. The robustness of the system is improved, and the effect of the load disturbance on the system is reduced. The results of the simulations and experiments show that the presented NFTSMC based on SMDO strategy has a strong torsional vibration suppression effect comparing to PI control and conventional sliding mode control.
Non-singular Fast Terminal Sliding Mode Control Torsional Vibration Suppression for PM Synchronous Transmission System of EVs
2023-12-12
PIER M
Vol. 122, 53-62, 2023
download: 95
Tensor-Based Robust Adaptive Beamforming for Multiple-Input Multiple-Output Radar Under Random Mismatch Scenarios
Ju-Hong Lee and Wei-Chi Lee
Adaptive beamforming for multiple-input multiple-output (MIMO) radar systems suffers from performance deterioration under the scenarios with multiple random mismatches. This paper explores the theory of tensor algebra and exploits the inherent multidimensional structure of data matrix received by MIMO radar systems. For dealing with the beamforming problem induced by multiple random mismatches including steering vector error, mutual coupling, sensor position error, and coherent local scattering, we develop a robust method based on a third-order tensor in conjunction with a gradient-based optimization process. The proposed method captures the multidimensional structure information embedded in the data matrix received by a MIMO radar and produces appropriate estimates for transmit and receive signal direction vectors required for beamforming. Using a third-order tensor helps to alleviate the effect of the multiple random mismatches in the tensor data domain. The gradient-based optimization process further enhances the capabilities of the third-order tensor in estimating transmit and receive signal direction vectors for adaptive beamforming of a MIMO radar. The main computational complexity of the proposed method is dominated by a trilinear alternating least squares algorithm and the well-known gradient-based algorithm. The proposed method provides better performance than the existing robust methods. Simulation results are presented to confirm the effectiveness of the proposed method.
Tensor-based Robust Adaptive Beamforming for Multiple-Input Multiple-Output Radar under Random Mismatch Scenarios
2023-12-12
PIER M
Vol. 122, 41-52, 2023
download: 100
Ultra-Wideband Antenna with Quintuple Band Notches Integrated with Metamaterials
Sapna Arora , Sharad Sharma and Rohit Anand
An elliptical monopole planar antenna for ultra-wideband (UWB) with penta-band-notched characteristics is presented. The frequency band rejection at 3.7 GHz to 4.2 GHz for C-band satellite communication and 5.15 GHz to 5.35 GHz for lower Wireless local area network (WLAN) is achieved by etching two elliptical split ring resonators (ESRRs) in the radiating patch. Dual notches at INSAT (4.5 GHz-4.7 GHz) and upper WLAN band (5.725 GHz-5.825 GHz) are created by special type of metamaterial, i.e., a two via double slot type EBG structure. Then, ITU band (7.95 GHz-8.55 GHz) is suppressed by adding a step impedance resonator (SIR) near the feed line. The proposed antenna is designed over a low cost FR4 material substrate, has a miniaturized size of 0.317λ × 0.317λ × 0.007λ, and possesses the impedance bandwidth from 2.5 GHz to 11 GHz. The band notch behaviour of antenna at specific frequencies is explained by mathematical model and justified with numerically simulated surface current distribution and impedance plot. Constant gain with the peak value of 3 dB is measured for UWB except notch bands. Also, this antenna has application in S(1.97-2.69 GHz), LTE(450 MHz-3.8 GHz), C(3.4-7.025 GHz), X(7.25-8.44 GHz), Ku(10.7-14.5 GHz) bands. The proposed antenna structure is a promising candidate for wireless technology.
Ultra-wideband Antenna with Quintuple Band Notches Integrated with Metamaterials
2023-12-12
PIER M
Vol. 122, 31-39, 2023
download: 110
Solving Electromagnetic Wave Scattering Using Artificial Neural Networks
Mohammad Ahmad
Electromagnetic wave scattering (EMWS) is one of the complexities in electromagnetism. Traditionally, three numerical methods are used to solve this problem which are finite element method, finite difference method, and method of moments. Recently, artificial neural networks (ANNs) have gained popularity as tools to solve different problems in a wide variety of disciplines, including electromagnetism. This paper shows that the second ordinary differential equation that represents EMWS from one-dimensional, two-dimensional, and three-dimensional inhomogeneous mediums and deals with complex numbers can be solved using ANN. This is done by reducing the error between the trail solution at the output of the ANN and the second ordinary differential equation that represents the scattered field. The results from solving classical examples using the suggested approach are accurate.
Solving Electromagnetic Wave Scattering Using Artificial Neural Networks
2023-12-12
PIER M
Vol. 122, 21-30, 2023
download: 150
Design of a Single-Layer C/X Dual-Band Reflectarray Antenna with Low Cross-Polarization
Li Liu , Yufeng Liu , Zhiyuan Yang and Liping Han
A single-layer reflectarray antenna working at C- and X-bands is designed in this paper. The proposed reflectarray element is mainly composed of three square rings. Four phase delay lines are attached to the outer ring to obtain the phase shift at C-band, and the inner two square rings are utilized to extend the phase range at X-band. The phase shift of the element reaches up to 375° and 560° at 5.9 GHz and 10.4 GHz, respectively. The cross-polarization level of the reflectarray is effectively suppressed by using a mirror symmetric element arrangement. To experimentally validate the proposed design, a center-fed dual-band prototype reflectarray with the size of 180 mm×180 mm is designed, fabricated, and tested. The measured peak gains are 16.5 dBi at 6.2 GHz and 17.1 dBi at 10.3 GHz, respectively. Besides, the measured 1-dB gain bandwidth is 9.15% (5.83-6.37 GHz) at the lower band and 3.27% (10.12-10.46 GHz) at the upper band, respectively. 16Dual-band shared aperture reflectarray and patch antenna array for s- and ka-bandsSerup, Daniel Edelgaard and Pedersen, Gert Frolund and Zhang, Shuai2340-2345SerupDaniel EdelgaardGert Frolund Pedersen, Shuai ZhangIEEE Transactions on Antennas and Propagation7023402345
Mar.2022journal10.1109/TAP.2021.31111713
Moreover, the cross polarizations at both bands are under -21 dB.
Design of a Single-layer C/X Dual-band Reflectarray Antenna with Low Cross-polarization
2023-12-05
PIER M
Vol. 122, 11-20, 2023
download: 149
Radio Frequency Energy Harvesting Device at ISM Band for Low Power IoT
Jefferson Ribadeneira-Ramírez , Jorge Santamaria , Patricio Romero and Mario Alejandro Paguay
Low Energy (LE) devices for communication systems like Bluetooth, 5G New Radio (NR), etc. are most likely to be powered by a battery, however, the limitation of the utilization time of this power supply entails it to be handled in different way; one of them is using electromagnetic energy harvesting paradigm, which could be capable to supply the energy consumption of this device. In this research it is presented the design and implementation of a device for radio frequency energy harvesting in the Industrial, Scientific and Medical (ISM) band. As first step, field intensity measurements in ``Facultad de Informatica y Electronica'' (FIE) were performed by the utilization of NARDA SRM 3006 radiation meter, with the aim of determining the technology with highest radio frequency (RF) energy within the 2.4 GHz ISM band. After the analysis, the chosen was WiFi technology due to the massive implementation that exists in the surroundings. Therefore, the frequency of 2.45 GHz was selected as the center frequency for the design. The device was implemented using FR4 Epoxy glass material with a dielectric permitivity of 4.4 and a dielectric thickness of 1.6 mm. The device consists of 3 stages: i) Capturing energy using a microstrip patch antenna ii) Rectification using a coupling network followed by a rectifying circuit and iii) Energy storage using the method of harmonic balance and electromagnetic moment. Finally, harvesting measurements were carried out in FIE's laboratory; the RF energy of a WiFi router was harvested and at 10 cm a voltage of 510.6 mV was obtained, this level of voltage was capable of turning on a led diode demonstrating the functioning of the device.
Radio Frequency Energy Harvesting Device at ISM Band for Low Power IoT
2023-12-04
PIER M
Vol. 122, 1-9, 2023
download: 150
Flexible Microstrip Patch Antenna Design on Jeans Substrate Radiating at 2.45 GHz for WBAN Application
Saikumar Mulkalla , Avish Fakirde and Paritosh D. Peshwe
This study presents a compact, low-profile, and flexible fabric antenna specifically designed for on-body Wireless Body Area Networks operating within the Industrial, Scientific, and Medical (ISM) frequency band at a central frequency of 2.45 GHz. The proposed antenna employs a jeans substrate, with a dielectric constant εr = 1.67 and loss tangent tanδ = 0.025, which is 0.5 mm in thickness, allowing for its flexibility. The antenna incorporates slots on the patch and a Defected Ground Structure (DGS), with a total size of 36 × 55 × 0.6 mm3 (0.29λo x 0.45λo x 0.005λo mm3). To assess the antenna's flexibility, bending analysis was performed, while its performance was evaluated using a phantom model that simulates human tissue, comprising skin, fat, and bone, with respective thicknesses of 1 mm, 0.5 mm, and 4 mm. The final model of the antenna operates at a central frequency of 2.45 GHz, with an impressive bandwidth of 0.8 GHz. The proposed design maintains a high level of directivity, gain, and Reflection Coefficient (S11) at the desired frequency, with values of 4.7 dBi, 3.6 dBi, and -41 dB, respectively. The Specific Absorption Rate (SAR) of the final antenna was measured on the above model and found to be 0.114 W/Kg for 1 g of tissue, which is well within the limits established by IEEE and FCC standards. Both the measured and simulated values of return loss and gain suggest that the proposed antenna is eminently suitable for body-worn applications.
Flexible Microstrip Patch Antenna Design on Jeans Substrate Radiating at 2.45 GHz for WBAN Application