PIER C | PIER Journals

2024-02-26

PIER C

Vol. 141, 205-215, 2024

download: 182

A Fast Coupled Iterative Approach for Computing 3D Composite Scattering from Dielectric Rough Surfaces and Target

Juan Zhao

This paper proposes a fast coupled iterative algorithm for calculating the complex three-dimensional scattering of rough dielectric surfaces and conductive targets. The algorithm is designed for practical composite electromagnetic scattering models and establishes a coupled iterative integral equation system for the rough surface and target. Iterative calculations are performed until the specified accuracy is achieved. To improve computational speed, Physics Based Two Grid-Sparse Matrix Canonical Grid (PB-SM) acceleration algorithm and a hybrid domain basis function based on quadratic surface modeling are applied using the fast Method of Moments (MoM) for fast computation. The effectiveness of the fast coupled iterative algorithm is verified by comparing the results with those of high-precision MoM calculations. During the calculation process, error iteration curves are plotted to show that the error can be reduced to 10^-6 after 10 iterations, and the convergence rate meets the requirements of practical calculations. Based on the algorithm proposed in this paper, several examples are calculated, and the scattering variation of targets in different environments is mainly studied, and suggestions are given to improve the accuracy of target detection and identification in complex environments. The results of the study have some significance for ultra-low altitude target detection, precision strike, stealth and anti-stealth.

A Fast Coupled Iterative Approach for Computing 3D Composite Scattering from Dielectric Rough Surfaces and Target

2024-02-19

PIER C

Vol. 141, 195-204, 2024

doi:10.2528/PIERC23082603

download: 242

Quad Band Split Octagonal Ring Antenna with Integrated Stub for Satellite Communication-Dependent Wireless Applications

Jambulingam Suganthi and Thamizhchelvan Kavitha

The purpose of this study is to design a multiband antenna using metamaterial for efficient satellite communication. The majority of the antennae described in the available research suffer from a variety of limitations, including intricate designs, great footprints, and erratic radiation patterns. Therefore, there is a significant demand for antennae that are of a smaller size but nevertheless perform well. This paper proposes a quad-band stub-incorporated split octagonal ring antenna for satellite communication-dependent wireless applications. The suggested antenna is built on an FR4 substrate that measures 22×39×1.6 mm³. CST EM studio software is used for the entire simulation. The proposed antenna resonates at four different bands, with operating frequencies ranging from 2.15 GHz to 2.30 GHz, 2.86 GHz to 3.76 GHz (due to stub 1), 4.47 GHz to 5.24 GHz (due to stub 2), and 5.67 GHz to 6.35 GHz (due to stub 3). (due to gap between the stub). The proposed antenna has resonant frequencies of 2.23 GHz, 3.28 GHz, 4.77 GHz, and 5.89 GHz, and bandwidths of 153 MHz, 9011 MHz, 7692 MHz, and 6813 MHz. Parametric analysis is used to select the best values. The designed antenna is built and tested. The measured and simulated values for return loss, gain, E-plane, and H-plane are compared, and they agree. Its dual-band operation, compact size, steady radiation pattern, and gain above 1 dBi across the whole resonating band make it suited for ISM, WIFI, WLAN, WIMAX, 5G, and C band satellite applications.

Quad Band Split Octagonal Ring Antenna with Integrated Stub for Satellite Communication-dependent Wireless Applications

2024-02-18

PIER C

Vol. 141, 185-193, 2024

doi:10.2528/PIERC23101906

download: 300

Improved Skew Method in Permanent Magnet Motor with Segmented Rotors for Reducing Cogging Torque

Sizhan Hua , Xueyi Zhang , Jun Zhang , Chenglong Yu , Fanxi Meng , Wei Wang , Kai Geng and Wenjing Hu

Rotor segment skew pole can effectively weaken the cogging torque, but the traditional rotor segment skew pole can also cause the unbalanced axial electromagnetic force, then add load to the bearing thus affecting the performance and decreasing the service life of the motor. It is complicated to study the effect of segment skew pole by the energy method. According to the generating mechanism of cogging torque, this paper presents an easy method. The relationship between segment number and cogging torque harmonics weakening is analysed through the application of geometrical relation and Fourier series, and a simple method for determining segment number is obtained. By analysing the main source of axial force in rotor segment, a new type of rotor arrangement is proposed, which can avoid excessive axial force while retaining the effect of traditional oblique pole mode on cogging torque weakening. The correctness of the conclusion is verified by finite element simulation and prototype experiment.

Improved Skew Method in Permanent Magnet Motor with Segmented Rotors for Reducing Cogging Torque

2024-02-17

PIER C

Vol. 141, 175-183, 2024

doi:10.2528/PIERC24011201

download: 235

An Adaptive Learning Co-Evolutionary Variational Particle Swarm Optimization Algorithm for Parameter Identification of PMSWG

Yang Zhang , Mingfeng Zhou , Wenxuan Luo and Zhun Cheng

Targeting the problems of traditional particle swarm algorithm easily falling into local optimum and low recognition accuracy, an adaptive learning co-evolutionary variational particle swarm optimization algorithm (ALCEVPSO) is proposed in this paper to identify the parameters of permanent magnet synchronous wind generator (PMSWG). At first, an adaptive learning strategy is adopted for the inertia weights of the PSO, and the global optimization seeking ability of the PSO is improved. After that, multiple swarm co-evolution strategies are introduced to share the best positions within sub-populations, and by this method, the algorithm's falling into local optimality is avoided. Finally, Cauchy Gaussian mixed variants are introduced, and the population diversity is enriched. The proposed method has the advantages of strong optimization ability and high search accuracy compared with the traditional particle swarm algorithm, which is shown by simulated and experimental results. By this method, the motor parameters of the permanent magnet synchronous motor can be accurately identified.

An Adaptive Learning Co-evolutionary Variational Particle Swarm Optimization Algorithm for Parameter Identification of PMSWG

2024-02-17

PIER C

Vol. 141, 163-173, 2024

doi:10.2528/PIERC24011001

download: 213

Finite-Control-Set Model Predictive Current Closed-Loop Control Based on Prediction Error Compensation for PMSM

Wenxuan Luo and Zhun Cheng

Finite-control-set model predictive control (FCS-MPC) for permanent magnet synchronous motors (PMSMs) has attracted attention due to its better theoretical performance. However, as motor operating conditions change, motor parameter mismatch can lead to intolerable prediction errors which significantly deteriorate stator current harmonics and torque ripples. To solve this issue, a finite-control-set model predictive current closed-loop control strategy is proposed. First, based on the analysis of the prediction equations, the voltage-independent and voltage-dependent parts of the prediction errors are separated. Secondly, according to the different features of prediction errors caused by zero and non-zero vectors, the decoupling of the two parts of prediction error is realized. And the PI controllers are introduced to observe the two different types of DC components respectively to make the observation more stable and accurate. Thirdly, feedback compensation is performed to modify the prediction equations. With the design of model predictive current closed-loop control, the prediction error quickly converges to the minimum. Finally, the experimental outcomes prove the effectiveness of this strategy.

Finite-control-set Model Predictive Current Closed-loop Control Based on Prediction Error Compensation for PMSM

2024-02-15

PIER C

Vol. 141, 151-162, 2024

doi:10.2528/PIERC23112003

download: 561

Dual-Band Implantable Antenna Loaded with Patch Slots for Wireless Biotelemetry Systems

Md. Masud Rana , Md. Ariful Islam and Ibrahim M. Mehedi

This paper presents a dual-band implantable antenna with coaxial probe feeding for wireless biotelemetry applications. The antenna features spiral patches, resulting in a compact size of 27 × 14 × 1.6 mm³. It can operate in two different frequency bands, 241-641 MHz and 1.17-2.06 GHz, providing coverage for the medical implant communication service (MICS) band and the industrial, scientific, and medical (ISM) band. This simple design offers improved return loss and higher bandwidths that are achieved by incorporating patch slots and shortening pins in spiral patches, representing a significant contribution to the field of dual-band antenna design for wireless biotelemetry systems. The SAR values of 48.9 mW/kg and 1.19 W/kg are achieved, which satisfy the IEEE standard safety constraints. An experimental prototype of the proposed antenna is fabricated which demonstrates acceptable return loss and VSWR.

Dual-band Implantable Antenna Loaded with Patch Slots for Wireless Biotelemetry Systems

2024-02-14

PIER C

Vol. 141, 143-150, 2024

doi:10.2528/PIERC23111104

download: 211

Tunable Filters Based on Fano Resonance Using Asymmetric Moving Resonators in a Single Loop System

Mimoun El-Aouni , Youssef Ben-Ali , Ilyass El Kadmiri , Younes Errouas , Abdelaziz Ouariach and Driss Bria

We report a novel characteristic of the phenomenon of Fano resonance obtained by the interaction of incident electromagnetic waves and waveguides system formed of loop and resonators. The Green Function Method (GFM) is employed to calculate the transmittance of the incoming electromagnetic waves. Our proposed system achieve a selecting and filtering device either by total transmission or by total reflection with a very high performance. The proposed structure contains four segments of the same lengths, and asymmetric resonators (N and N' resonators) are moving in the structure. Through parameters optimization, we show that the system creates Fano resonances, which are sensitive to the variations of the segment lengths, the resonator lengths, the positions of the resonators and the physical properties of the system components. Then, the proposed system is able to filter at least two resonance modes with different frequencies. This system has potential applications in the field of microwave communication antennas.

Tunable Filters Based on Fano Resonance Using Asymmetric Moving Resonators in a Single Loop System

2024-02-13

PIER C

Vol. 141, 133-141, 2024

doi:10.2528/PIERC23092503

download: 196

Weather Radar High-Resolution Spectral Moment Estimation Using Bidirectional Extreme Learning Machine

Zhongyuan Wang , Ling Qiao , Yu Jiang , Mingwei Shen and Guodong Han

Since the performance of the spectral moment estimation algorithm commonly used in engineering degrades under the conditions of low SNR, this paper introduces the Extreme Learning Machine (ELM) to the spectral moment estimation of weather signals based on the correlation of the signals of adjacent range cells. To solve the problem that the hidden layer nodes of ELM algorithm are difficult to be determined, the Bidirectional Extreme Learning Machine (B-ELM) algorithm is applied to achieve the high resolution of spectral moments. Firstly, to improve the SNR of the training samples, time-domain pulse signals are converted into weather power spectrum by Welch method. Then, the parameters of the B-ELM hidden layer nodes are directly calculated by backpropagation of network residuals. The model parameters are optimized according to the least-squares solution, where the optimal number of hidden layer nodes is determined adaptively. Finally, the optimized B-ELM model is employed for the spectral moment estimation of weather signals. The algorithm is validated to be fast and accurate for spectral moment estimation using the measured IDRA weather radar data and is easy to implement in engineering.

Weather Radar High-resolution Spectral Moment Estimation Using Bidirectional Extreme Learning Machine

2024-02-13

PIER C

Vol. 141, 123-132, 2024

doi:10.2528/PIERC23121601

download: 207

Research on the Control System of Bearingless Induction Motor Based on Improved Active Disturbance Rejection Control

Xiang Wang , Zebin Yang , Xiaodong Sun and Shihan Zhan

To enhance the reaction speed, suspension performance, and anti-interference ability of a Bearingless Induction Motor (BIM) operation control system, an improved Active Disturbance Rejection Control (ADRC) technique is proposed. Firstly, the ADRC in the suspension system and the ADRC in the torque system are designed, respectively, using the BIM's mathematical model as the basis. Furthermore, the error integral signal is incorporated into the nonlinear state error feedback control law of the standard ADRC controller. Subsequently, a novel optimal control function is formulated using the fitting method, which is based on the original fal function. This approach effectively mitigates the impact of output signal fluctuations at the inflection point of the fal function. Simultaneously, the RBF neural network technique is employed to autonomously adjust the control parameters of the extended state observer, therefore enhancing the system's observation capability. Ultimately, the classic ADRC control strategy and the IADRC strategy are compared through simulation and experimentation. Simulations and experimental findings demonstrate that the suggested control method enhances the BIM control system's response time and resilience to external disturbance. Additionally, it enhances the levitation performance of the BIM system.

Research on the Control System of Bearingless Induction Motor Based on Improved Active Disturbance Rejection Control

2024-02-13

PIER C

Vol. 141, 109-121, 2024

doi:10.2528/PIERC23122301

download: 212

Decoupling Control of Bearingless Permanent Magnet Synchronous Motor Based on Least Squares Support Vector Machine Inverse System Optimized by Improved Grey Wolf Optimization Algorithm

Huangqiu Zhu , Jiankun Du and Gai Liu

The characteristics of nonlinear and strong coupling of a bearingless permanent magnet synchronous motor (BPMSM) greatly affect the improvement of its control performance. In the traditional decoupling control of least squares support vector machine (LSSVM) inverse system, the kernel function parameter σ and regularization parameter c are determined according to the empirical value, but not the nonoptimal value, so large error exist in the decoupling control. Therefore, this paper proposes a decoupling control method of LSSVM inverse system based on improved grey wolf optimization algorithm (IGWO). Firstly, the working principle of the BPMSM is described, and the mathematical model is derived. Secondly, the reversibility of the BPMSM is analyzed, and the σ and c of LSSVM are optimized by IGWO, before establishing a generalized inverse system for decoupling control. Thirdly, the simulation tests of the speed regulation and anti-interference are carried out, which show that the decoupling performance of the proposed method is better than the traditional LSSVM inverse system method. Finally, the dynamic experiments, static experiments and anti-interference experiments are carried out. The feasibility and superiority of the proposed method are verified according to the built experimental platform.

Decoupling Control of Bearingless Permanent Magnet Synchronous Motor Based on Least Squares Support Vector Machine Inverse System Optimized by Improved Grey Wolf Optimization Algorithm

2024-02-07

PIER C

Vol. 141, 101-108, 2024

doi:10.2528/PIERC23120601

download: 168

Co-Optimization of Long Secondary Double-Sided Linear Flux Switching Permanent Magnet Motors

Cheng Wen , Jian Cui , Mingye Li , Zhiping Wan and Yujian Chang

This study aims to achieve the co-optimization of thrust force and thrust fluctuation using a long secondary double-sided linear flux switching permanent magnet motor (LSDLFSPM). Firstly, the motor model is constructed and derived using a theoretical approach. Subsequently, the motor parameters are subjected to sensitivity analysis using the Taguchi method to identify the significant influencing factors. Based on the screening results, the Response Surface Method (RSM) is employed to construct the test space and derive regression equations for thrust force and thrust fluctuation. The Multi-Objective Grasshopper Optimization Algorithm (MOGOA) is then utilized to iteratively optimize the regression equation for optimal parameter sizes. Finally, the optimized results are validated through finite element analysis (FEA) and compared with the original motor performance to demonstrate the effectiveness of the optimization approach proposed in this paper.

Co-optimization of Long Secondary Double-sided Linear Flux Switching Permanent Magnet Motors

2024-02-05

PIER C

Vol. 141, 89-100, 2024

doi:10.2528/PIERC23110402

download: 401

A Novel Approach Utilizing Graphene-Based Microfluidic Technology for Skin Cancer Detection

Marwa Rezeg , Aymen Hlali , Afef Oueslati and Hassen Zairi

The introduction of microfluidics technology with graphene provides many advantages, such as improving the selectivity and sensitivity, achieving chemical and thermal stability, decreasing the size of devices, and impoving the cell and The biological response of the substance. The principal objective of this paper is to compare the constitutive parameters in order to develop graphene-based microfluidic sensors. The simulation results illustrate that the suggested sensor exhibits a strong ability in detecting normal skin tissue with an exellent sensitivity of 6.060 (THz/RIU) and to identify skin cancer with a notably significant sensitivity of 4.59 THz/RIU. Additionally, it shows considerable figure of merits, with values of 550.9 and 353.61 RIU, respectively. In conclusion, the simplicity, effectiveness, and adjustability of the proposed biosensor render it well-suited for breast tumor detection.

A Novel Approach Utilizing Graphene-based Microfluidic Technology for Skin Cancer Detection

2024-02-04

PIER C

Vol. 141, 79-87, 2024

doi:10.2528/PIERC23091402

download: 241

Synthesis and Characterization of Polymer (PDMS-FE₃O₄) Magneto-Dielectric Material Based on Complementary Double Split Ring Resonator

Fatin Hamimah Ikhsan , Yee See Khee , Samsul Haimi Dahlan , Fahmiruddin Esa and Vahid Nayyeri

In this paper, a comparison microwave method between Transmission and Reflection using a Coaxial Cable and complimentary double split ring resonator (CDSRR) for characterization of magneto-dielectric material is proposed. This method enables the determination of both relative permittivity and permeability of magneto-dielectric material. The CDSRR resonates at 3.46 GHz with a quality factor of 127 in unloaded condition. To determine the effects of permittivity and permeability on the shift of resonant frequency, the electric and magnetic fields are localized in two separate zones in the CDSRR sensor. Prediction formulas are proposed to extract the value of real permittivity and permeability from S₂₁ parameter. For Transmission/Reflection Method, to extract the dielectric and magnetic properties, Nicolson-Ross-Weir (NRW) are used. The prototypes of proposed sensors are fabricated on a ROGERS 3003 and tested for validation of their functionality. A good agreement between the measured data using Transmission/Reflection Method and CDSRR sensor is observed.

Synthesis and Characterization of Polymer (PDMS-Fe<sub>3</sub>O<sub>4</sub>) Magneto-dielectric Material Based on Complementary Double Split Ring
Resonator

2024-02-05

PIER C

Vol. 141, 67-78, 2024

doi:10.2528/PIERC23100302

download: 269

Impact of Laser Cutting on Iron Loss in High Speed Machines

Shruti Singh , Andrea Credo , Ilya Petrov , Juha Pyrhönen and Pia Marjatta Lindh

In electrical machines, most of the iron loss estimation in finite element modeling is based on Bertotti coefficients obtained from the corresponding data sheet. However, often a more exact estimation of coefficients for the laminated steel material is needed. Especially in the case of high speed machines (where iron loss has the highest contribution to the total loss), it is very difficult to estimate the iron loss variation as a result of laser cutting when just using data sheet information as input data in finite element analysis. Laser cutting impacts also the magnetic properties, in terms of magnetization curves at different frequencies, not only the core losses. In this paper, three different core materials of the same lamination steel are prepared to realize the estimation of the Berttotti loss coefficient when the material is subjected to high frequency and under the stress of laser cutting. Experimental analysis is performed to obtain more precise values of Bertotti coefficients at a high frequency range so that they can be utilized in iron loss estimation in a high speed machine (100 krpm maximum speed-1667 Hz) which is further shown as an application. Finally, it is shown how frequency domain iron loss results can be utilized for the time stepping iron loss analysis.

Impact of Laser Cutting on Iron Loss in High Speed Machines

2024-02-02

PIER C

Vol. 141, 53-65, 2024

doi:10.2528/PIERC23112407

download: 281

Design and Analysis of Quad Dumbbell Shaped Directive UWB Antenna for Microwave Tumour Detection Integrated with Meander Strip Resonators

Asheesh Gupta and Madan Lal Meena

A novel design of a dumbbell shape quad elliptical slotted (DSQES) antenna for directive ultra-wideband (UWB) integrated with WCDMA, WLAN, and mid-band of 5G applications is presented. Initially, a circular patch is designed by inserting four elliptical slots in radiator with a rectangular slotted ground plane. To realize ultra-wide impedance bandwidth, three symmetrical stepped rectangular slots are inserted in ground below a stepped-quarter-wave transformer feed line. The proposed antenna achieves fractional bandwidth (FBW) of 104% (S₁₁ < -10 dB) which covers UWB frequency range of 5.4-17.3 GHz at resonant frequencies 5.8/7.4/10.3/12/15.7 GHz. Further, a ground structure is customized by loading two asymmetrical meander strip resonators (MSRs), which provides extra lower frequency bands 2.1 GHz (1.96-2.21 GHz) and 3.5 GHz (3.22-4.07 GHz) for WCDMA, WLAN, and 5G mid-band applications, respectively. Furthermore, the measured gain and half-power-beam-width (HPBW) are 1.7-6.4 dBi and 75°-20° in 5.4-17.3 GHz UWB, respectively. The optimized dimension of proposed antenna is 30×30 mm² which is simulated on Computer Simulation Technology (CST) electromagnetic simulator using an FR-4 substrate of thickness 1.6 mm and dielectric constant 4.3. The simulated structure is computed by ADS simulator, and simulated results are validated with measured ones.

Design and Analysis of Quad Dumbbell Shaped Directive UWB Antenna for Microwave Tumour Detection Integrated with Meander Strip Resonators

2024-02-03

PIER C

Vol. 141, 41-52, 2024

doi:10.2528/PIERC23122101

download: 216

Study on Anti-Offset Performance of Dynamic Wireless Charging System with Reverse Series Double-Layer Symmetrical Coil for Electric Vehicles

Xiangfei Li , Xin Zhou , Shentao Zou , Yu Cheng , Xiaohua Shu , Xinbo Xiong , Ziyue Gan and Zhongqi Li

In dynamic wireless charging systems for electric vehicles (EVs), the coupling mechanism is difficult to align, which leads to high output voltage fluctuations and low transmission efficiency of the system. A reverse series double-layer symmetrical coil (RSDSC) structure with magnetic core is proposed. First, the mutual inductance characteristics of this structure are analyzed based on its coupling structure. Secondly, a mutual inductance optimization method is proposed to obtain the optimal values of each parameter of the coil and the optimal values of the magnetic core parameters. Finally, a wireless power transfer system is built based on the obtained coil and magnetic core parameters, and the correctness of the structure is verified through simulation and experimentation. The results show that the maximum mutual inductance fluctuation of the structure of RSDSC with magnetic core is only 4.88%, and the efficiency is up to 97.86% when the receiving coil is offset within 50% (20.8 cm) of the outer length of the transmitting coil.

Study on Anti-offset Performance of Dynamic Wireless Charging System with Reverse Series Double-layer Symmetrical Coil for Electric Vehicles

2024-02-01

PIER C

Vol. 141, 33-40, 2024

doi:10.2528/PIERC23110704

download: 361

A Compact Sierpinski Gasket Fractal Antenna for S, C, X, and Ku Band Applications

Ezhumalai Aravindraj , Ganesan Nagarajan and Palaniappan Ramanathan

A Sierpinski Gasket Fractal Structure embedded in an Octagonal Microstrip Printed Monopole Antenna is proposed. The prototype is mathematically developed in a miniaturized cross-sectional area with ultra-wide resonance. A fractal design resembling a third-order Sierpinski gasket is applied to the octagonal radiator in a mutually proportional manner, increases the radiation across the entire surface area by extending the effective length of the dielectric. Additionally, the partial ground alters the resonant modes of TM11 and TM21 to a second-order iterative response via two contactless slots. Also, the driven radiator exhibits Fractional Bandwidth (FBW) of 156% spanning at 2.65 GHz-21.6 GHz, along with a peak gain 6.23 dB. The fabricated prototype demonstrates excellent agreement during testing and measurement using a microwave analyzer and an anechoic chamber, respectively. The proposed antenna covers resonance for applications at the S, C, X, and Ku bands. Also, it completely envelopes the Ultra-Wideband (UWB) and Sub-6 GHz 5G spectrum.

A Compact Sierpinski Gasket Fractal Antenna for S, C, X, and Ku Band Applications

2024-01-30

PIER C

Vol. 141, 25-32, 2024

doi:10.2528/PIERC23121001

download: 275

A Low-Profile UHF RFID Tag Antenna Loaded with Rectangular Loop for Double-Sided Anti-Metal Applications

Jinhao Wang and Jiade Yuan

A low-profile ultra-high frequency (UHF) radio frequency identification (RFID) tag antenna for double-sided anti-metal applications is proposed. The antenna comprises a middle layer of radiation patch, which is sandwiched between two layers of foam substrates, each with a thickness of 0.5 mm, and flanked by two layers of ground plane. A rectangular loop is designed on the radiation patch to expand the frequency band and optimize impedance matching. Particularly, one side of the radiation patch is shorted to the ground through a slotted stub to reduce the antenna size. The tag antenna is compact with a dimension of 38 mm × 20 mm × 1.15 mm (0.1159λ × 0.061λ × 0.0035λ at 915 MHz). When the two ground planes are individually mounted on metallic objects, the read distances are 5.4 m and 5.2 m, respectively. The proposed tag antenna demonstrates double-sided metal resistance, making it highly suitable for use in the industrial internet of things field.

2024-01-29

PIER C

Vol. 141, 13-23, 2024

doi:10.2528/PIERC23120801

download: 349

RIS-Assisted Wireless Channel Characteristic in Coal Mine Tunnel Based on 6G Mobile Communication System

Shuqi Wang and Wei Zhang

In the context of 6G communication technology, Reconfigurable Intelligent Surfaces (RIS) can effectively reconfigure signal propagation paths through the adjustment of their passive metamaterial reflector units. This capability mitigates the issue of radio wave attenuation in the complex environments of mine tunnels by optimizing signal paths, thereby reducing energy loss and minimizing coverage dead zones. By utilizing RIS-assisted multi-antenna terrestrial mobile communication channels and ray tracing techniques, researchers have established a wireless channel fading model specifically for rectangular coal mine tunnels. The results suggest that under comparable conditions, RIS technology enhances low-frequency signals (e.g., 2.4 GHz) more effectively than high-frequency signals (e.g., 30 GHz). Furthermore, these improvements are more pronounced as the size of the RIS increases.

RIS-assisted Wireless Channel Characteristic in Coal Mine Tunnel Based on 6G Mobile Communication System

2024-01-29

PIER C

Vol. 141, 1-11, 2024

doi:10.2528/PIERC23122502

download: 342

Characteristic Mode Analysis for Microstrip Fed Conformal Metasurface Multiband Antenna

Kothakonda Durga Bhavani , Boddapati Taraka Phani Madhav , Yalavarthi Usha Devi , Yarlagadda Ramakrishna and Mudunuri Padmanabha Raju

In this study, an optimal multi-band microstrip fed metasurface antenna is designed. Three by three non-uniform circular radiating cross slotted elements make up the antenna's metasurface. The metasurface is analyzed using characteristic mode analysis (CMA), and the Modal Significance (MS), Characteristic angle (CA), and Eigen Value (EV) curves are utilized to optimize the antenna's performance. In addition, surface currents are examined for the metasurface and patch using CMA, and the design incorporates microstrip feeding to excite the targeted frequency bands. With its resonance frequencies of 5.4 GHz, 8.9 GHz, 12.8 GHz, 15.9 GHz, and 19.8-31.58 GHz, the developed antenna has potential uses in 5G and wireless communications. The suggested antenna achieves a gain of 10.05 on average. The prototyped model conformability analysis of the antenna is also performed, and good matching with simulation results is found.