PIER C | PIER Journals

2025-02-19

PIER C

Vol. 152, 271-277, 2025

download: 44

Antenna Designs Using Kriging Assisted Taguchi Method

Jianing Ma, Xingning Jia, Ruidong Wang and Liao Ma

Taguchi method has been extensively applied in electromagnetic optimization. To further enhance the optimization efficiency of the Taguchi method, a surrogate-assisted Taguchi method employing dynamic reduced rates is proposed. The reduced rate of each design variable is proportional to its contribution percentage. Variables with higher contributions exhibit a larger reduction rate, which subsequently decreases the search step and enhances the exploitation and convergence of the Taguchi method. The Kriging model serves as a substitute for the real fitness evaluation in predicting the result of each experiment, with its feasible state determined by the average relative error of its predictions. This ensures the prediction accuracy while reducing the number of real fitness evaluations. The proposed algorithm is validated by the fact that the efficiency has increased at least twofold through four benchmark function tests. In the end, this algorithm is employed to synthesize the radiation pattern of an asymmetrical dipole array with 16 elements and to optimize the front-to-back ratio of the Yagi-Uda antenna.

Antenna Designs Using Kriging Assisted Taguchi Method

2025-02-19

PIER C

Vol. 152, 263-270, 2025

doi:10.2528/PIERC25010301

download: 19

Polarization-Insensitive, Integrally Rectifying Metasurface Array for Ambient Energy Harvesting

Congcong Xia, Hongmei Zhao, Yunfei Wang and Mingxing Ren

In this paper, an integrated rectifying metasurface harvester with small dimensions, wide-angle incidence, and polarization insensitive characteristics is proposed. The proposed structure is assembled from a periodic unit cell, diodes, and loads, which makes the structure simple and less expensive to manufacture. The centrosymmetric design concept of the unit cell structure enables the proposed metasurface harvester to capture incident waves with arbitrary polarization angles and over a wide incident angle range of 60°. A 5 x 5 metasurface array was fabricated for real measurements. The results show that the measured efficiency is 62.07% near the operating band 5.8 GHz when the incident power is 15 dBm. When the polarization angle of the incident wave is changed, the efficiency remains essentially constant. As the angle of incidence changes, the efficiency shows a certain decrease, but it can still maintain an efficiency close to 50% near the operating frequency band. The proposed harvester can supply energy to low power devices as well as sensor nodes in IoT.

Polarization-insensitive, Integrally Rectifying Metasurface Array for Ambient Energy Harvesting

2025-02-19

PIER C

Vol. 152, 259-262, 2025

doi:10.2528/PIERC24122205

download: 19

Extinction Efficiency of Copper Nano Fibers in the Infrared

Sharhabeel Alyones and Michael Granado

This article presents experimental measurements and theoretical calculations of the mass normalized extinction cross section (extinction efficiency) of hydrothermally synthesized copper nanofibers in the infrared spectral region (2-14) µm. The synthesized copper nanofibers have an average diameter of 40 nm, and the length of the fibers has been ultrasonically reduced to achieve the highest possible efficiency in the targeted IR spectral region. A peak extinction efficiency of ~30 M²/g is achieved with an overall efficiency greater than 10 M²/g across the remainder of the infrared window. Such high efficiency fibers make them of high interest for applications that require attenuation of electromagnetic radiation. To the best of our knowledge, this efficiency is the highest that has been reported in literature, and the synthesis procedure is simple and can be scaled-up for mass production of copper nanofibers.

Extinction Efficiency of Copper Nano Fibers in the Infrared

2025-02-18

PIER C

Vol. 152, 253-258, 2025

doi:10.2528/PIERC24122403

download: 21

Novel Hexagonal Cross-Coupled Dielectric Waveguide Filter

Xiao Tao Yao, Yun Xiu Wang, Yang Gao and Jiankang Zhang

In this paper, a six-order cross-coupled ceramic dielectric waveguide filter (CDWF) based on equilateral triangle resonators is introduced. It is composed of a regular hexagonal cavity, which is divided into six equilateral triangular blocks. The filter exhibits two transmission zeros outside the passband that ensure its out-of-band suppression greater than 45 dB. Measured results show that the insertion loss is less than 1 dB and the return loss more than 16 dB within the operating frequency range of 3.4-3.6 GHz. The ceramic dielectric used here has a dielectric constant of 20.3 and a thickness of 5 mm. Thus, it has the advantages of compact size and excellent frequency selectivity.

Novel Hexagonal Cross-coupled Dielectric Waveguide Filter

2025-02-18

PIER C

Vol. 152, 245-251, 2025

doi:10.2528/PIERC24122101

download: 23

An Optimized Phase-Only Trapezoid Taper Window for Array Pattern Shaping

Jafar Ramadhan Mohammed

Generally, the array pattern synthesizing can be shaped by controlling the excitation amplitude and phase of the individual elements of the antenna array which they could be controlled either separately or jointly to provide most flexible solutions for the desired pattern shaping. In this paper, a new controllable trapezoid phase-only taper is proposed. In practical applications, phase-only tapers are more preferable than amplitude-only tapers due to their desirable advantages. The required pattern shaping with fulfilled user-defined constraints on the sidelobe peaks, beam widths, and steered nulls can be achieved by optimizing only the excitation phases of the trapezoidal taper. More importantly, the proposed trapezoidal taper offers the best tradeoff between the array directivity and undesirable sidelobe pattern. In addition, the element excitation amplitudes of the proposed phase-only trapezoid taper are made constant and equal to that of the original trapezoid taper function. Thus, it enjoys low array complexity. Moreover, the manipulated phases are assumed to be symmetric to further simplify the array feeding network. The genetic algorithm was used to optimize only the half number of the elements' phases. The results show that the phase-only trapezoid taper yields identical main beam shape to that of the amplitude-only trapezoid taper and much better than the other conventional tapers. Furthermore, it is found that the trapezoid phase-only method needs more variable elements than the trapezoid amplitude-only method to achieve almost the same performance. Thus, the complexity reduction percentage of the phase-only method is lower than that of the amplitude-only method.

An Optimized Phase-only Trapezoid Taper Window for Array Pattern Shaping

2025-02-17

PIER C

Vol. 152, 233-243, 2025

doi:10.2528/PIERC24111105

download: 43

A High Isolation Four-Element MIMO Antenna for 5G n256 -Band Satellite Communication and 6G Applications

Fanran Zhang, Chengzhu Du and Xu Wu

In the present work, a dual-band four-port multiple-input multiple-output (MIMO) antenna based on an FR4 substrate is designed, which can work in the frequency bands of 5G n256/n77/n78/n79 and 6G system. The MIMO antenna is composed of four orthogonally placed monopole antennas. Multiple sets of L-shaped branches and cross-shaped branches are added to improve the isolation among the antenna elements. The measured isolation is below -20 dB, and most of them can reach -30 dB within the operational frequency spectrum. The actual measurement results reveal that the two impedance bandwidths of the antenna are 420 MHz (1.95-2.37 GHz) and 4050 MHz (3.2-7.25 GHz), respectively, which can encompass the n256 band for 5G-6G satellite technologies (1.98-2.01 and 2.17-2.2 GHz), 5G n77/n78/n79 (3.3-4.2/3.3-3.8/4.4-5.0 GHz) and 6G band (6.425-7.125 GHz). At the same time, the antenna features a peak gain of 7.4 dB. The ECC value is below 0.0015, while the DG value exceeds 9.9999, showing good diversity performance. The data reveal that the designed dual-band quaternary MIMO antenna has good applications in the fields of 5G satellite communication and 6G systems.

A High Isolation Four-element MIMO Antenna for 5G n256-band Satellite Communication and 6G Applications

2025-02-16

PIER C

Vol. 152, 221-231, 2025

doi:10.2528/PIERC24120306

download: 31

Impact of Quantum Conductivity on a Reconfigurable Single Wall Carbon Nanotube Dipole Performance at Optical Frequency Bands

Muhanad Musa Jameel and Jawad A. Hasan

The proposed antenna system integrates advanced materials electromagnetic properties tuning to allow real-time steering to the antenna main beam direction. We explore a tuning mechanism based on changing the chemical potential differences (μc), through including a chiral single wall carbon nanotube (SWCNT) structure with a plasmonic resonance effect at the optical regime. Such change in the value of μc realizes a manipulation in the angular emission pattern change to enhance the beamforming capabilities to the desired requirements. This steerability provides substantial benefits for applications such as optical communication systems. The obtained results validate that the proposed nano-dipole antenna shows significant improvements over other traditional antennas in terms of size reduction with acceptable radiation efficiency, directivity, and tunability. The integration of the proposed design within next optoelectronic generations can floor the way to the compact, high-performance systems with enhanced capabilities for optical communication systems and photonic circuitry. This study presents a steerable plasmonic nano-dipole antenna with dynamic electromagnetic radiation control, designed for modern communication. The antenna operates across a wide frequency range, with a primary focus on the visible spectra 300 THz to 700 THz. By utilizing resonant plasmonic effects, the antenna achieves a radiation efficiency of 57% and a directivity of 4.5 dBi. We introduce a beam-steering mechanism that enables angular radiation steering up to ±25° from the central axis. Control mechanisms include electrical tuning via applied μc voltage from 0 V up to 1 V and optical tuning using laser excitation around 600 THz. Simulations confirm that beamwidth narrows from 30° to 10° at resonance, enhancing spatial precision. The validated results show a tunability of 200 THz in the operational wavelength, with a response S11 below -10 dB. These features demonstrate that the antenna operation has a potential for integration into next-generation optoelectronic devices, offering compact and efficient solutions for wireless communication, remote sensing, and optical imaging systems. This is achieved by leveraging the resonant interaction between surface plasmon polaritons and nano-dipole geometry, and we demonstrate the ability to achieve highly directional and tunable radiation across a wide range of frequencies, including visible and near-infrared spectra.

Impact of Quantum Conductivity on a Reconfigurable Single Wall Carbon Nanotube Dipole Performance at Optical Frequency Bands

2025-02-15

PIER C

Vol. 152, 209-219, 2025

doi:10.2528/PIERC24123103

download: 63

Broadband Eight-Element MIMO Antenna with High Isolation for 5G Smartphone Applications

Zhonggen Wang, Shunqi Liu, Wenyan Nie, Ming Yang and Chenlu Li

To satisfy the demand for 5G communication to smartphone terminal antennas in element quantity and isolation, an eight-element broadband MIMO antenna system with high isolation is proposed in this paper. The antenna element consists of an L-shaped feed line and a rectangular slot with an open slot. Meanwhile, a stepped impedance tuning structure was integrated within the rectangular slot to optimize broadband impedance matching and expand the operational bandwidth. In addition, a Chinese character ``工''-shaped defective ground structure has been innovatively designed to reduce surface wave coupling on the ground plane, achieving an isolation level of over -15 dB. Furthermore, eight antenna elements and six defective ground structures are symmetrically distributed along the long edges of the substrate, with coupling feeding performed through the L-shaped feed lines. The proposed antenna system ultimately achieves an operating bandwidth of 3.4-6.5 GHz below -10 dB, with a total efficiency greater than 90% and an envelope correlation coefficient of less than 0.016. The stability of the system in overlay screen mode, as well as in single-handed and dual-handed smartphone operation modes, is also demonstrated to showcase its practical applications.

Broadband Eight-element MIMO Antenna with High Isolation for 5G Smartphone Applications

2025-02-14

PIER C

Vol. 152, 197-208, 2025

doi:10.2528/PIERC24111401

download: 38

Design and Analysis of a Delta-Shaped Segmented Variable Leakage Flux Reverse-Salient Permanent Magnet Synchronous Machine for Electric Vehicles

Xiping Liu, Jiao Guo, Ruipan Lu, Zhangqi Liu and Baoyu Sun

Since the traditional Delta-shaped motor is difficult to achieve the wide speed range while increasing the output torque, it cannot fully meet the complex working conditions of electric vehicles. This paper, from the driving conditions and the principle of variable leakage magnetism, based on the traditional Delta-shaped interior motor, designs a variable leakage flux permanent magnet synchronous motor with a segmented Delta-shaped rotor permanent magnet structure (VLF-DSPM). The permanent magnet is segmented into a magnetic bridge by a ferromagnetic material so that some magnetic lines do not pass through the permanent magnet but directly through the magnetic bridge to increase the d-axis inductance. A magnetic barrier is designed in the q-axis to achieve magnetic leakage in the high-speed region, thereby achieving a wide speed control range. In addition, since the utilization rate of the permanent magnet is reduced due to segmentation, the output torque is reduced. Therefore, transverse bar-shaped permanent magnets are added to increase the reluctance torque of the motor to achieve a higher resultant torque. The key parameters of this structure were then optimized, and finally the electromagnetic characteristics of the VLF-DSPM were studied using finite element analysis in comparison with a conventional Delta-shape interior permanent magnet (DS-IPM) synchronous motor. The results show that the VLF-DSPM has better flux control capabilities, higher output torque, a wider speed range, and higher efficiency and power factor.

Design and Analysis of a Delta-shaped Segmented Variable Leakage Flux Reverse-salient Permanent Magnet Synchronous Machine for Electric Vehicles

2025-02-11

PIER C

Vol. 152, 187-195, 2025

doi:10.2528/PIERC24112903

download: 31

Multi-Motor Synchronous Control Strategy Based on Fuzzy Internal Model PID and Virtual Spindle Synchronous Control

Wei Yan and Shasha Li

To achieve high-precision synchronous control of multiple motors, this study utilizes a permanent magnet synchronous motor as a case study. It adopts a fuzzy internal model proportional-integral-derivative algorithm with integral separation for single-motor control. On this basis, the virtual spindle synchronization strategy of multi-motor synchronous control and the fuzzy control algorithm are further introduced to adjust the feedback torque compensation coefficient dynamically, optimizing the virtual spindle synchronization strategy. The results showed that in single-motor control, the dual closed-loop fuzzy proportional-integral control algorithm achieved a torque fluctuation error of 4 N.m when the load torque changed significantly. The fuzzy internal model proportional-integral-derivative control algorithm with integral separation had a relatively smooth adjustment process, and the maximum torque fluctuation did not exceed 1 N.m. In multi-motor synchronous control, the improved virtual spindle synchronous control strategy had a synchronization error of only 14.2 r/min between motor 1 and motor 2, as well as between motor 1 and motor 3. The single-motor and multi-motor synchronous control strategies used in the study have high control accuracy and response efficiency, which is conducive to improving the synchronization accuracy and coordination between motors. The improved strategy provides a reliable control scheme for industrial automation systems.

Multi-motor Synchronous Control Strategy Based on Fuzzy Internal Model PID and Virtual Spindle Synchronous Control

2025-02-09

PIER C

Vol. 152, 177-186, 2025

doi:10.2528/PIERC24091802

download: 77

A Frequency and Polarization Reconfigurable Transparent Water Antenna

Lei Li, Jing Gao and Jingchang Nan

A novel frequency and polarization reconfigurable water patch antenna is proposed for radio communication in the UHF band. Based on theoretical analysis and simulation results, water is an ideal material for designing transparent liquid ground. Water enhances outstanding transparency, excellent aesthetics, and high optical stealth performance for a wider range of application scenarios. The entire structure is made with polyvinyl chloride material and distilled water, except for the feed structure. By filling different cavities with liquid water, six different operating states are obtained in 1.924-2.5 GHz (26.1 %), 1.67-2.33 GHz (33 %), 0.644-2.288 GHz (112.1 %), 1.975-2.54 GHz (25 %), 1.748-2.108 GHz (18.7 %), and 1.988-2.348 GHz (16.6 %), achieving frequency reconfigurability. The antenna can be flexibly switched between linear polarization (LP) and two right-handed circular polarization (RHCP) states. The results show that the 3 dB axial ratio (AR) bandwidth covers 1.93-2.08 GHz (7.5 %) and 2.06-2.132 GHz (3.5 %). The antenna achieves high optical transparency of 100 % and a peak gain of 7.97 dBi.

A Frequency and Polarization Reconfigurable Transparent Water Antenna

2025-02-04

PIER C

Vol. 152, 171-176, 2025

doi:10.2528/PIERC24120302

download: 59

Adaptive Hybrid Precoding for Reliable Multi-User mmWave MIMO Systems

Pillala Venkata Muralikrishna and Teppala Venkata Ramana

Wireless communication has revolutionized modern connectivity, with millimeter-wave (mm-Wave) technology emerging as a key component of next-generation networks due to its ability to deliver fast data rates and large capacity. Hybrid precoding is an important approach in mm-Wave MIMO systems for optimizing spectral efficiency, and it relies largely on accurate channel state information (CSI). The sparse characteristic of mm-Wave channels allows compressive sensing (CS) methods to be used for efficient channel estimation, considerably lowering pilot overhead and computational complexity. This study describes a novel hybrid precoding technique designed for reliable multi-user situations. The proposed two-stage framework uses SVD-based equal-gain transmission (EGT) for analog precoding and a Kalman filter for baseband precoding to effectively reduce inter-user interference. Numerical assessments show that the EGT-Kalman precoding method is comparable with standard strategies like zero-forcing (ZF) and MMSE precoding in terms of spectral efficiency. Furthermore, the pilot overhead is calculated, indicating the efficiency of the suggested technique in reducing training requirements while maintaining performance. This study highlights the promise of adaptive precoding techniques in developing mm-Wave communication systems by providing resilient performance in stable multi-user scenarios while tackling the challenges of sparse channel estimation.

Adaptive Hybrid Precoding for Reliable Multi-user mmWave MIMO Systems

2025-02-04

PIER C

Vol. 152, 163-170, 2025

doi:10.2528/PIERC24121802

download: 39

Low-Profile Wide Axial-Ratio Beamwidth Circularly Polarized Antenna with Simple Feed

Wenying Lu, Xiao Ding and Wei Shao

To effectively receive circularly polarized (CP) waves at large angles, it is necessary for antennas to have large axial ratio beamwidth (ARBW). For instance, geostationary satellite receiver antennas employed in regions with high latitudes necessitate a broad ARBW. In this paper, the mechanism to broaden ARBW is analyzed, and a CP antenna with low profile is designed and fabricated. With L-shaped branches and vertical extension segments (VESs), ARBW of the proposed antenna has been effectively broadened. Moreover, compared with recently reported wide ARBW artworks, it features a simple structure and feeding mechanism. The proposed antenna within the working bandwidth (from 4.79 to 4.95 GHz, 3.3%) achieves a 3 dB ARBW of 243° in the φ= 0° plane while the 3 dB ARBW reaches 199° in the φ= 90° plane. The measured results agree well with the simulated ones.

2025-02-03

PIER C

Vol. 152, 151-161, 2025

doi:10.2528/PIERC24102904

download: 58

Efficient Technique for HTS Coupled Resonator Filters Design Using an Enhanced FDTD Algorithm

Mohamed Karim Laoufi, Slimane Mekaoui, Mohamed Lamine Tounsi and Mustapha Yagoub

In this paper, an enhanced FDTD algorithm is proposed for efficient characterization of HTS (high temperature superconductors) microwave planar filters. The developed algorithm, which can be generalized to any microwave planar circuit, is based on the two-fluid phenomenological model. Further, an irregular mesh discretization allowed improving the CPU time. Also, the thermal effects and the normal conductivity have been rigorously taken into account for better performance. The impact of the operating temperature as well as the choice of the superconductor thickness was investigated. Computed results are in good agreement with simulated data using commercial software.

Efficient Technique for HTS Coupled Resonator Filters Design Using an Enhanced FDTD Algorithm

2025-02-03

PIER C

Vol. 152, 143-149, 2025

doi:10.2528/PIERC24121701

download: 56

Comparison and Analysis of Dual-Stator Magnetic Field Modulation Motors with Different Permanent Magnet Arrangements

Libing Jing, Tao Wang, Zeyu Min and Weizhao Tang

The Double Stator Magnetic Field Modulation Motor (DSMFMM) realizes the magnetic field modulation effect and optimizes the torque ripple effect by accurately optimizing the flux line. In order to further explore the influence of permanent magnets (PMs) magnetization model on the performance of DSMFMM, this paper conducts a comparative study on the performance of three motors with radial magnetization, Halbach magnetization, and Spoke magnetization. Firstly, three motor models are designed based on the same outer radius and axial length, and the flux lines of the three motors are analyzed in detail. Secondly, the static and dynamic performances of the three models are compared by finite element analysis (FEA) method. Compared with the conventional radial magnetization structure, the DSMFMM structure with Halbach magnetization and Spoke magnetization improves the output torque and torque density of the motor.

Comparison and Analysis of Dual-stator Magnetic Field Modulation Motors with Different Permanent Magnet Arrangements

2025-02-03

PIER C

Vol. 152, 131-141, 2025

doi:10.2528/PIERC24111104

download: 62

Multifunctional Dual-Band Microwave Sensor for the Detection of Liquid Permittivity and Solid Displacement

Habib Nurseha Anggradinata and Muhamad Asvial

This study proposes a dual-band microwave sensor based on a split-ring resonator (SRR) coupled with a pair of L-shaped structures. The proposed sensor has dual functionalities, including the detection of liquid permittivity and solid displacement. An ethanol-water mixture is selected as a sample to measure the permittivity of the liquid. Moreover, FR4 is chosen as the test sample to measure the displacement of the solid. As a result, the maximum frequency detection resolution (FDR) is 1.64, and the average FDR is 1.40. The maximum and average normalized sensitivity (NS) values are 0.073% and 0.06%, respectively. The maximum displacement sensitivity is 10.0 MHz/mm for f_DS2 and 10.5 MHz/mm for f_DS1, while the average displacement sensitivity values are 4.98 MHz/mm and 8.02 MHz/mm for f_DS2 and f_DS1, respectively. These values confirm the sensor's reliable performance and sensitivity across different measurements. In general, the proposed sensor offers several advantages: 1) it operates independently by isolating the electric fields generated by each sensor; 2) it demonstrates dual functionalities, including the detection of liquid permittivity and solid displacement; and 3) it is capable of handling both liquid and solid samples.

Multifunctional Dual-band Microwave Sensor for the Detection of Liquid Permittivity and Solid Displacement

2025-02-02

PIER C

Vol. 152, 121-129, 2025

doi:10.2528/PIERC24122203

download: 99

Innovative Design for Mutual Coupling Reduction in Dual-Element Array Antennas for ISM Applications Using Whale Optimization Algorithm

Elham Atashpanjeh and Pejman Rezaei

This paper introduces a decoupled dual-element array antenna designed to address the challenges of mutual coupling between elements. To tackle this issue, a neutralization line is strategically incorporated to suppress leaky surface currents, while ensuring the antenna's central frequency and radiation pattern remain intact. The dimensions of the neutralization line are carefully optimized using the Whale Optimization Algorithm (WOA) to achieve the best possible performance, focusing on minimizing mutual coupling and enhancing gain. By placing the neutralization line nearby between the two elements, surface currents are efficiently redirected back to the radiating element, preventing leakage to neighboring elements. This approach also results in a more compact structure. The proposed antenna, with overall dimensions of 50 mm x 30 mm x 1.6 mm, is simulated using analytic software. It achieves an impressive 27 dB reduction in mutual coupling and delivers an ultra-wide bandwidth of 1.2 GHz within the ISM band at an operating frequency of 2.4 GHz, with a measured maximum gain of -5 dB. The structure was fabricated, and experimental results closely matched the simulations, confirming the design's effectiveness. By leveraging the WOA optimization method, the geometry of the neutralization line was fine-tuned to maximize performance, significantly improving inter-element decoupling. This design approach is simple yet effective and can be readily extended to other antenna array configurations, demonstrating strong potential for compact and efficient Industrial Scientific and Medical (ISM) band applications.

Innovative Design for Mutual Coupling Reduction in Dual-element Array Antennas for ISM Applications Using Whale Optimization Algorithm

2025-01-31

PIER C

Vol. 152, 111-120, 2025

doi:10.2528/PIERC24120508

download: 106

On Selecting Activation Functions for Neural Network-Based Digital Predistortion Models

Mostapha Ouadefli, Mohamed Et-tolba, Abdelwahed Tribak and Tomas Fernandez Ibanez

Neural networks have become a focal point for their ability to effectively capture the complex nonlinear characteristics of power amplifiers (PAs) and facilitate the design of digital predistortion (DPD) circuits. This is accomplished through the utilization of nonlinear activation functions (AFs) that are the cornerstone in a neural network architecture. In this paper, we delve into the influence of eight carefully selected AFs on the performance of the neural network–based DPD. We particularly explore their interaction with both the depth and width of the neural network. In addition, we provide an extensive performance analysis using two crucial metrics: the normalized mean square error (NMSE) and the adjacent channel power ratio (ACPR). Our findings highlight the superiority of the exponential linear unit activation function (ELU AF), particularly within deep neural network (DNN) frameworks, among the AFs under consideration.

2025-01-30

PIER C

Vol. 152, 103-110, 2025

doi:10.2528/PIERC24120602

download: 51

Switchable/Tunable Dual-Band BPF for Bluetooth and 5G NR Applications

Areeg F. Hussein, Malik Jasim Farhan and Jawad K. Ali

This article presents a dual-band switchable and tunable band-pass filter for Bluetooth and 5G NR applications. The filter functions at 2.41 GHz for Bluetooth and 3.55 GHz for 5G, utilizing independent switching and tuning methods facilitated by PIN and varactor diodes. The suggested design exhibits compact dimensions of 0.177λ_g x 0.096λ_g, a minimal insertion loss of 0.35 dB, and a substantial return loss of 30 dB. Advanced design methodologies, including defective ground structures (DGS) and eigenmode analysis, were utilized to attain precise selectivity and exceptional out-of-band rejection. The engineered filter demonstrates superior performance, with outcomes closely aligning with models, and guarantees little interference with suppression up to 10 GHz. The tuning mechanism provides versatility by independently modifying the operating frequencies of the second band, rendering the design very flexible for dynamic wireless communication settings. This study emphasizes a robust and effective answer for contemporary mobile communication systems.

Switchable/Tunable Dual-band BPF for Bluetooth and 5G NR Applications

2025-01-25

PIER C

Vol. 152, 91-101, 2025

doi:10.2528/PIERC24112501

download: 82

Design of a High-Gain Millimeter Wave Array MIMO Antenna for 5G

Wenhui Liu and Xinchun Li

To deal with the problems of low gain and low data transmission rate of millimeter wave antenna during long-distance transmission, a high-gain millimeter wave array multiple-input-multiple-output (MIMO) antenna with series-parallel hybrid feed is proposed. The radiating structure consists of a combination of multiple rectangular patches, to make the proposed design resonate within the desired frequency band of 39 GHz. The antenna line array consists of eight radiating patches connected in series via transmission lines, providing an operating bandwidth of 1.02 GHz and a peak gain of 15.9 dB, and utilizing the Chebyshev synthesis method to control the side lobe level below -20 dB. In order to obtain higher gain, two antenna line arrays are connected through a Y-shaped feeding network, which utilizes the mutual coupling between the antennas to increase the bandwidth of the antenna to 1.25 GHz and provide a simulated gain of 17.6 dBi. Furthermore, the proposed array antennas are placed side-by-side to form a four-port MIMO antenna, which does not require any decoupling structure and has the isolation of more than 25 dB. The radiation efficiency is as high as 99%, the Envelope Correlation Coefficient (ECC) less than 0.003, and the Diversity Gain (DG) greater than 9.98. The measured results show that the operating frequency band of the antenna is 38.0∼39.6 GHz, and the operating bandwidth is 1.6 GHz. In the operating frequency band, the peak gain of the antenna is 17.45 dBi, Finally, the frequency characteristics and radiation characteristics of the antenna when bending are analyzed. The results show that the bending of the antenna leads to a slight shift in the resonant frequency, but the relative bandwidth remains unchanged. The gain has decreased, indicating that the antenna is able to work normally after bending and has a wider range of application scenarios.

Design of a High-gain Millimeter Wave Array MIMO Antenna for 5G

2025-01-22

PIER C

Vol. 152, 81-89, 2025

doi:10.2528/PIERC24120403

download: 49

Direction-of-Arrival Estimation Method of Single Snapshot Coherent Source Based on Hyperbolic Tangent Kernel Correntropy

Hongyuan Gao, Kailong Liu and Ying Guo

To solve the problem of low accuracy and real-time performance of direction of arrival (DOA) estimation in an impulsive noise environment, this paper proposes a single-snapshot DOA estimation method based on the median deviation correntropy of hyperbolic tangent kerne and designs an intelligent optimization algorithm for the segmentation and hunting mechanism of gold long-nosed raccoon to obtain accurate DOA estimation angle. The DOA estimation method proposed in this paper uses spatial smoothing technology to process the median deviation correntropy of single snapshot data, and then uses the hyperbolic tangent kernel to remove impulse noise from the pseudo-covariance matrix. The weighted signal subspace fitting method is used to obtain the accurate DOA estimation angle. The Monte Carlo analysis experiments of different schemes are verified, especially in the case of a single snapshot, low generalized signal-to-noise ratio (GSNR), and strong impulse noise.

Direction-of-arrival Estimation Method of Single Snapshot Coherent Source Based on Hyperbolic Tangent Kernel Correntropy

2025-01-20

PIER C

Vol. 152, 73-80, 2025

doi:10.2528/PIERC24120901

download: 56

Dual-Band Filters with Adjustable Bandwidth and Wide Stopband Using CRLH Transmission Line Theory

Chen Li, Minquan Li, Zhonghui Li, Shuangqing Cao and Rongxian Bai

In response to the growing demands of modern communication systems for miniaturized devices, high selectivity, and multi-band characteristics, this paper proposes a design methodology for a dual-band filter based on a planar interdigital structure. Two dual-band filters are developed utilizing transmission zeros and cascading techniques. The filters exhibit high selectivity and wide stopband performance. They are also tunable through parameter adjustments while maintaining a compact form factor. By incorporating composite right/left-handed (CRLH) theory, the proposed filters demonstrate left-handed characteristics. Simulation and experimental results indicate that the designed filters achieve low insertion loss, a wide stopband, and excellent out-of-band rejection within the target frequency bands. Additionally, compared to existing designs in the literature, this approach offers notable advantages in terms of both size and performance. The findings of this study show significant potential for applications in RF and communication systems.

Dual-band Filters with Adjustable Bandwidth and Wide Stopband Using CRLH Transmission Line Theory

2025-01-18

PIER C

Vol. 152, 67-72, 2025

doi:10.2528/PIERC24112003

download: 81

Structural Optimization and Performance Evaluation of Liquid Cooled Super Fast Charging Cable Based on Multi-Physics Coupling Calculation

Yanrong Ni, Shupeng Zhao, Xiaohe Zhao and Kaituo Zhang

Super fast charging is a key solution to addressing the issue of electric vehicles. In response to the demand for increased current-carrying capacity and lightweight cables in super-fast charging system, optimization design and verification were conducted in this study employing a multi-physics field analysis method. A single-core cable was selected as the research subject, and both the Ohmic loss and temperature distribution were analyzed under the excitation of electric vehicle cold charging current. The influence of different cable core shapes, coolant flow rates, cooling channel structural parameters, and other factors on the maximum temperature rise of the charging cable were compared and analyzed. The calculation results indicated that, under the identical cable core cross-sectional and operating conditions, rectangular cross-section cables exhibited superior heat dissipation performance compared to circular cross-section cables. It was found that the flatter the cable core is, the better the heat dissipation performance is. Under specific operating conditions, the cross-sectional area of the flat linear shape could be reduced appropriately, as increasing the size of the liquid cooling channel would help reduce the overall mass of the cable. These findings provide valuable insights for enhancing the heat dissipation performance and lightweight design of liquid-cooled charging cables in supercharging applications.

Structural Optimization and Performance Evaluation of Liquid Cooled Super Fast Charging Cable Based on Multi-physics Coupling Calculation

2025-01-18

PIER C

Vol. 152, 55-66, 2025

doi:10.2528/PIERC24101401

download: 108

A Broadband Half-Mode Substrate Integrated Waveguide Cavity Antenna with Triple-Resonances

Dian Widi Astuti, Huda Bin Abdul Majid, Syah Alam and Andri Setyawan

A simple, low-profile, and broadband antenna is presented in this paper for bandwidth enhancement. The compact antenna is achieved through a 50% miniaturization of a full-mode substrate integrated waveguide (FMSIW) antenna, known as the half-mode substrate integrated waveguide (HMSIW). The low-profile design is the result of the thin substrate thickness. However, the miniaturized and low-profile antenna suffers from narrow impedance bandwidth, which limits its application in antenna implementations. To address this issue, this paper proposes a broadband antenna in a single HMSIW cavity, offering a simple solution. The broadband performance is achieved by the merging of triple resonances. These triple resonances are generated by the combination of TE₁₀₁, TE₁₀₂, and TE₂₀₂ modes, which are induced by a semi-rectangular ring slot on the top layer of the cavity. Good agreement is observed between the simulation and measurement results. The simulated fractional bandwidth (FBW) is 29.53% (9.67-13.02 GHz), while the measured FBW is 32.05% (9.51-13.14 GHz). Two identical antennas with different polarization directions are obtained by mirroring one of them with respect to the other.

A Broadband Half-mode Substrate Integrated Waveguide Cavity Antenna with Triple-resonances

2025-01-18

PIER C

Vol. 152, 43-53, 2025

doi:10.2528/PIERC24111702

download: 139

A Miniaturized Quad Port Highly Isolated Triple Band Notched UWB-MIMO Diversity Antenna

Thotakura Sushma, Rajesh Gogineni, Nallagonda Vijaya Ratnam, Sadineni Ramesh Babu, Sunitha Mandava and Paruchuri Venkata Krishna Kanth

In this study, a quad-port ultra-wideband (UWB) multiple input multiple output (MIMO) antenna with triple band-rejection characteristics is demonstrated. The suggested diversity MIMO antenna comprises four similar rectangular radiators positioned in orthogonal manner by utilizing polarization diversity. For superior interelement isolation, a fan-shaped decoupler is lithographed on the back of the substrate. The MIMO antenna exhibits an operational bandwidth of 9 GHz (3-12 GHz) for each port, with |S₁₁| ≤ -10 dB. This version is more concise and properly formatted. The MIMO aerial exhibits an impedance bandwidth 3-12 GHz) for each port (|S₁₁| ≤ -10 dB) along with an interelement isolation exceeding 20 dB. Additionally, to exclude the 3.5-4.1 GHz (downlink C-band), 4.43-4.79 GHz (INSAT), and 5.25-5.71 GHz (Wireless LAN) bands that coexist in UWB spectrum, the antenna elements are equipped with three U-shaped slots. The MIMO diversity metrics, including isolation, envelope correlation coefficient, diversity gain, TARC, CCL, multiplexing efficiency and group delay, were computed and reported. The reported aerial prototype has been constructed, and the measured results have been validated against the simulated findings.

A Miniaturized Quad Port Highly Isolated Triple Band Notched UWB-MIMO Diversity Antenna

2025-01-15

PIER C

Vol. 152, 33-41, 2025

doi:10.2528/PIERC24121304

download: 67

Research on Constant Current Output Control of Wireless Power Transmission System Based on Parameter Identification

Zhongjiu Zheng, Yanpeng Ma, Zhilong Wu, Xingfeng Cao, Qiangqiang Zhao and Jinjun Bai

In the complex marine environment, the receiver is susceptible to the influence of water flow, which will cause the mutual inductance to fluctuate, thus affecting the stability of the output current. Therefore, aiming at the problem that the coil is prone to offset, this paper proposes a constant current charging output control method for wireless power transmission system based on parameter identification. Firstly, a method of mutual inductance parameter identification is introduced in detail. Only by measuring the effective value of the current at the transmitting end, the equivalent equation of mutual inductance and current can be established. Aiming at solving complex mathematical equations, the results of mutual inductance identification are obtained from high-order equations by combining with particle swarm optimization algorithm. Secondly, on this basis, a constant current control method for fast calculation of the conduction angle based on the above identification method is proposed. The calculation process of the conduction angle is derived, and the working principle of the constant current charging control is introduced in detail. Finally, this paper completed the construction of the experimental platform and carried out relevant experimental verification. The results show that the error of the parameter identification method proposed in this paper is within 3%, and the constant current output control of the system can be realized in the case of mutual inductance disturbance.

Research on Constant Current Output Control of Wireless Power Transmission System Based on Parameter Identification

2025-01-12

PIER C

Vol. 152, 25-32, 2025

doi:10.2528/PIERC24101801

download: 105

Broadband Circularly Polarized Crossed Dipole Antenna Loaded with Magneto-Electric Dipole

Zhuopeng Wang, Xin Zhang, Haoyu Fang, Ao Ni and Yanhui Cheng

A right-hand circularly polarized (RHCP) crossed dipole antenna with wide impedance and axial ratio bandwidth is developed. The antenna is composed of a pair of crossed dipoles, four parasitic patches, a metal reflecting cavity and 12 metal support posts. The four parasitic patches and 12 metal support posts together constitute two pairs of magneto-electric dipoles. By using a quarter wavelength phase delay ring on the crossed dipole, the 90° phase difference between the upper and lower arms is obtained, thereby realizing circularly polarized radiation. By adding slotted parasitic patches, grounded metal posts, and modifying the cavity structure, the circular polarization performance of the antenna is improved. The measurement results show that the antenna with a compact size, low cost obtains 64.5% of impedance bandwidth (1.85-3.61 GHz) and 59.6% of axial ratio bandwidth (1.92-3.55 GHz), and has stable pattern and gain in the operating bandwidth, highlighting significant potential for future applications in sub-6 GHz 5G applications.

Broadband Circularly Polarized Crossed Dipole Antenna Loaded with Magneto-electric Dipole

2025-01-11

PIER C

Vol. 152, 19-24, 2025

doi:10.2528/PIERC24081403

download: 69

An Interleaved Dual-Band Outline Elliptical Dipole Antenna

Jonathan Marquardt, Maria Pour and Curtis Hill

A new dual-band antenna is presented for use in space-based passive energy harvesting. This antenna is based on elliptical dipole antennas, whose inner metallization is removed, leaving an outline antenna and room for a second set of antenna arms. This will in turn result in an interleaved structure to tune each set of dipole arms to two different frequencies. Due to the close proximity of the dipole arms there exists strong mutual coupling, which is lessened by adding decoupling elements to the design. The proposed antenna is supported by a partial ground plane to improve the front-to-back ratio of the radiation patterns. The ground plane is extended with an exponential taper, and additional parasitic elements are added to improve antenna performance. The dual-band elliptical outline design was fabricated and measured, and the results are found in good agreement with simulation. This antenna design provides 14 dB return loss, 3.4 dBi peak gain, and 12 dB front-to-back ratio for both the 0.915 GHz and 2.45 GHz bands, making it a useful antenna for applications such as passive energy harvesting that require lightweight dual-band designs.

An Interleaved Dual-band Outline Elliptical Dipole Antenna

2025-01-11

PIER C

Vol. 152, 13-18, 2025

doi:10.2528/PIERC24102105

download: 94

A Low-Cost Four Circularly Polarized Antenna Loaded with a Complementary Split Ring Resonator for Beam Steering Applications

Oumaima Nayat-Ali, Fatima Zohra Khoutar, Mariem Aznabet, Otman El Mrabet and Mohsine Khalladi

In this work, a novel circularly polarized antenna with four ports and loaded with complementary split ring resonator (CSRR) for beam steering applications without phase shifters or PIN diodes is presented. The single antenna loaded with CSRR is arranged in a rotational manner forming a 4-port structure. The separation distance among the four antennas is optimized for achieving a steering angle of 29° with an isolation level greater than 25 dB over the whole bandwidth. When one of the four antennas is excited, the others either open-circuited or terminated to a 50-Ω impedance, the antenna has a resonant frequency of 5.8 GHz and produces a left-hand circularly polarized (LHCP) tilted beam in the elevation plane. The introduction of the CSRR leads to achieving a small design and also to get circular polarization characteristics. The proposed structure has a radiation efficiency of 90 % and a gain of 6 dBi over the whole bandwidth. This characteristic can be tuned which makes the proposed design suitable for many modern communication systems.

A Low-cost Four Circularly Polarized Antenna Loaded with a Complementary Split Ring Resonator for Beam Steering Applications

2025-01-08

PIER C

Vol. 152, 1-12, 2025

doi:10.2528/PIERC24102502

download: 105

Design of a Low-Cost Printed Slotted SIW Antenna Array with Omnidirectional Azimuth Pattern and Beam-Shaped Elevation Pattern

Tadeu Pasetto and Hugo Enrique Hernandez-Figueroa

This paper presents the design, discussions, and characterization of a low-cost printed slotted substrate integrated waveguide traveling wave antenna. The antenna exhibits an omnidirectional pattern in the azimuth plane and a cosecant squared pattern in the elevation plane. This synthesized pattern enables application in 5G mm-wave systems by providing a defined signal equipotential region, thereby increasing coverage areas in locations such as stadiums, exhibition centers, arenas, and parks. Additionally, the proposed design method facilitates the easy implementation of new designs tailored to specific installation sites.