PIER C | PIER Journals

2025-05-14

PIER C

Vol. 155, 213-224, 2025

download: 49

Design and Optimization of Ultra-Wideband Dual-Notch Antenna Based on the BOLGB-DE Algorithm

Huawei Zhuang, Jianzhao Liu, Fangzhen Sun, Gaoqi Li and Fanmin Kong

With the rapid development of modern communication technologies, the use of ultra-wideband (UWB) notch antennas in various communication systems has increased significantly. However, designing UWB notch antennas with traditional methods often involves high complexity and low efficiency. To address the challenge, a novel optimization method, named BOLGB-DE (Bayesian optimization-Light Gradient Boosting Machine-Differential Evolution), is proposed. First, the BOLGB model is selected as the surrogate model to establish the relationship between antenna design parameters and performance. Then, the DE algorithm is used to invoke the BOLGB surrogate model to achieve the antenna optimization objectives. Compared to the traditional method, BOLGB-DE method enables the reduction of electromagnetic simulations by 62% (from 1176 to 440 runs) and optimization time by 62% (from 22.8 hours to 8.6 hours). Finally, a UWB dual-notch antenna is designed using the BOLGB-DE method, featuring a dual-notch structure within the 1.9 GHz-10.1 GHz range. It achieves two notch bands (3.58 GHz-4.17 GHz for C-band downlink shielding and 5.12 GHz-5.38 GHz for 5G Wi-Fi interference suppression) while maintaining the target S₁₁ values greater than -7 dB. The design requirements are successfully met by the antenna, as confirmed by the measurement results.

Design and Optimization of Ultra-wideband Dual-notch Antenna Based on the BOLGB-DE Algorithm

2025-05-13

PIER C

Vol. 155, 203-211, 2025

doi:10.2528/PIERC25022001

download: 48

Design of a Miniaturized Circular Flower-Shaped Fractal Antenna with a Defected Ground Structure for Multiband Applications

Sanae Attioui, Asma Khabba, Saïda Ibnyaich, Abdelouhab Zeroual, Zahriladha Zakaria and Ahmed Jamal Abdullah Al-Gburi

The increasing demand for compact, cost-effective, and versatile antennas in modern wireless communication systems has inspired research into innovative multiband antenna designs. However, numerous existing solutions are insufficient in terms of size, bandwidth, or manufacturing complexity, particularly when they aim to incorporate multiple wireless standards within a compact device. To address this gap, this study proposes a miniaturized fractal antenna design measuring 15 × 11 × 1.6 mm³, fabricated on a low-cost FR-4 substrate. The proposed antenna is inspired by nature, featuring a flower-shaped patch and a defected ground (DGS) with a spiral pattern. It exhibits multiband behavior, resonating at six distinct frequencies: 1.79 GHz, 3.84 GHz, 7.34 GHz, 9.08 GHz, 11.44 GHz, and 14.6 GHz, making it suitable for various wireless applications, including GSM/UMTS (1.7-2.1 GHz), 4G/5G and radar (3.3-4.2 GHz), military radar and satellite communications (7-8 GHz), aviation and maritime radar (8.5-10 GHz), satellite communication in the Ku-band (10.7-12.7 GHz), and advanced radar and satellite uplinks (12-14 GHz). The fabricated antenna was tested, and the experimental results demonstrated a strong correlation with the simulated outcomes, confirming its practical applicability and effectiveness in multiband communication systems. The proposed fractal antenna stands out due to its compact size, multiband capability, and excellent performance, making it well suited for modern wireless applications.

Design of a Miniaturized Circular Flower-shaped Fractal Antenna with a Defected Ground Structure for Multiband Applications

2025-05-12

PIER C

Vol. 155, 195-201, 2025

doi:10.2528/PIERC25021103

download: 24

Online Targets Tracking and People Counting Using Multiple Distributed mmWave Radar Sensors

Uday Kumar Singh and Thipparaju Rama Rao

With the growing use of radar sensors, particularly in surveillance applications, there is an increasing need for real-time target tracking, especially in areas such as counting people. This paper offers a detailed description of the hardware setup, which is paired with a proposed fusion algorithm and the multiple-target tracking (MTT) algorithm for online target tracking. The fusion techniques introduced in this work combine data from spatially distributed Texas Instruments mmWave radar sensors by utilizing the likelihood of radar measurements. These sensors measure the positions of the reflectors, which are then visualized through the Robot Operating System (ROS). To support real-time target tracking and people counting, a connection is established between the ROS network and MATLAB. Finally, the measurements are processed in MATLAB using the proposed fusion technique alongside the existing MTT algorithm to generate accurate target tracks, which also enable people counting.

Online Targets Tracking and People Counting Using Multiple Distributed mmWave Radar Sensors

2025-05-11

PIER C

Vol. 155, 189-194, 2025

doi:10.2528/PIERC24121103

download: 19

Modified IPD Expression for Radomes with Large Curvature

Pei Jia, Yong-Jun Xie, Chunyu Li, Ke Pang, Zhiping Li, Jiahui Zhao and Peiyu Wu

Primary insertion phase delay (IPD) expression is obtained using the flat plate model with plane wave incidence, and it only considers the longitudinal phase shift in the free space. This causes errors in large curvature radome applications since the longitudinal distance that wave travels in flat plate cannot represent the actual distance. Therefore, the IPD expression for radomes with large curvature should be defined. Based on the ray tracing in the radome medium, a modified IPD expression with more accurate transmission distance for large curvature radomes is proposed. The proposed expression can be applied to radomes with arbitrary curvature. The correctness of our proposed expression is verified via a simplified fast radome analytical model. The results from the proposed expression show errors within 1.0° for the parabolic radome system. The proposed expression can be applied to optimize the performance of radome systems with large curvature. A reflector antenna radome system is employed for verification. Results show that using the modified IPD expression to optimize the reflector antenna can increase the system gain by 1.8 dB, reduce the side lobe by 7.6 dB, and narrow the beamwidth by 0.9°.

Modified IPD Expression for Radomes with Large Curvature

2025-05-10

PIER C

Vol. 155, 177-187, 2025

doi:10.2528/PIERC25021403

download: 40

Design and Analysis of a Triple-Band Stacked T-Polyimide Antenna for WBAN Applications

Kodali Rani Rudrama, Vallabhuni Tulasi Naga Kalyan, Bachalakuri Shini and Marampudi Vamsi

A low-profile, flexible and wearable microstrip patch antenna is presented for Wireless Body Area Networks (WBANs) applications. Wearability is one of the latest developments in electronic devices leading to real-time monitoring of human vital signs like blood pressure, body temperature, and pulse rates using WBAN technology. A monopole antenna with a planar rectangular and six stacked T-shaped elements is positioned on the top side of the radiating patch. A partial ground structure is incorporated at the bottom of the patch to generate triple band characteristics. The antenna is maintained with compact dimensions which are 65 × 65 × 0.1 mm³. The antenna operates at tri-band frequencies, such as 2.7 GHz, 2.5 GHz, and 3.5 GHz, to support 5G applications. At 2.45 GHz, the directivity is 1.56; the VSWR is 1.13; the gain is 15.38; and the reflection coefficient (S₁₁) of −26.91 dB. The SAR value of 0.160 W/kg satisfies IEEE safety requirements for biomedical applications and is much below the allowed maximum of 1.6 W/kg for 1 gram of tissue. This guarantees safe and effective operation in wearable and medical applications. The antenna has a thickness of 0.1 mm, a relative permittivity of 3.5 and provides flexibility and durability. The presentation includes the comparative analysis and the step-by-step design of the triple-band flexible antenna. Testing on a three-layer human phantom model made up of skin (2 mm), fat (8 mm), and muscle (23 mm) demonstrated the antenna's performance in terms of gain, radiation patterns, VSWR, reflection coefficient (S₁₁), and specific absorption rate (SAR). The parametric analysis, performance evaluation, simulation results, and iterative process of the antenna design are all presented in detail. Along with conclusions, comparisons to other designs, and useful estimations, the results and finalized antenna are presented. The accurate difference between measured and simulated performances indicates the antenna's reliability and efficiency, and its compact size increases flexibility in wide range of environments. The antenna was simulated using HFSS software, fabricated, and validated in an anechoic chamber and using a network analyzer.

Design and Analysis of a Triple-band Stacked T-polyimide Antenna for WBAN Applications

2025-05-08

PIER C

Vol. 155, 165-175, 2025

doi:10.2528/PIERC25013002

download: 51

Design of a Compact Sub-6 GHz Wideband Filtering Patch Antenna Without Extra Structure

Noor Kareem Mohsin and Dhirgham Kamal Naji

This paper presents a new compact filtering patch antenna (FPA) design that achieves a wideband impedance bandwidth (IBW) without extra structure. It addresses the limitations of traditional FPAs, which often rely on extra elements to enhance bandwidth and filtering performance. The proposed FPA consists of a radiating patch with an inscribed circular slot, excited by a feedline integrated with a quarter-wavelength matching stripline, all located on the top side of an FR4 substrate. A partial ground plane with a T-shaped symmetrical branch strip is printed on the bottom side of the substrate. The combination of the T-shaped strips and the matching stripline creates the first radiation-null f_n1 near the lower edge of the passband antenna's gain response. Furthermore, the introduction of a circular slot into the radiating patch creates a second radiation-null f_n2 in the upper edge of the passband region. This not only enhances the IBW but also contributes to the antenna's efficient filtering characteristics. Simulation tools CST Microwave Studio (MWS) and High-Frequency Structure Simulator (HFSS) are used to evaluate key performance parameters, including reflection coefficient (S₁₁), realized gain, and radiation patterns. A fabricated prototype validates these simulations, demonstrating a -10 dB fractional IBW of 47.36% (2.9-4.7 GHz). Based on CST and HFSS simulation results, the design exhibits high selectivity with suppression levels of over 22 dB and 23.7 dB at the lower and upper stopband edges, respectively, while maintaining a flat gain across the passband. The antenna also provides omnidirectional radiation patterns and has a compact size of 29 x 35 x 0.8 mm³, making it more promising for 5G sub-6 GHz applications.

Design of a Compact Sub-6 GHz Wideband Filtering Patch Antenna without Extra Structure

2025-05-08

PIER C

Vol. 155, 159-164, 2025

doi:10.2528/PIERC25031901

download: 32

Compact Wideband Reflective Phase Shifter with Wide Phase Shift Range and Simple Control

Teng Ma, Hongmei Liu, Yuyang Jiang and Zhongbao Wang

In the paper, a planar wideband reflective phase shifter (RTPS) with wide phase shift range and simple control is proposed. It consists of a coupled-line based wideband 3-dB coupler and two multi-resonance reflective loads. By combining a series resonant circuit with a shunt resonant circuit to form multi-resonances, the phase shift range can be expanded with realizable capacitance values of the varactor diodes. The design equations are derived, and parametric analysis is provided. To verify the feasibility of the design methodology, an RTPS operating at the center frequency of 2 GHz is designed and fabricated. Measured results show that it exhibits a better than 10 dB input return loss bandwidth of 33.9% and a phase shift range of 320°. Besides, the size of the RTPS is only 0.41λ_g × 0.13λ_g, and can be controlled by simply one voltage.

Compact Wideband Reflective Phase Shifter with Wide Phase Shift Range and Simple Control

2025-05-07

PIER C

Vol. 155, 147-157, 2025

doi:10.2528/PIERC25031201

download: 23

Design of Sparse Wideband Frequency-Invariant Beamforming Based on Hybrid Grey Wolf-L_∞-Norm Algorithm

Guihan Xie, Bin Wang and Kui Tao

A novel hybrid algorithm is proposed for frequency-invariant (FI) beam pattern synthesis of wideband nonuniformly spaced array (NUSA), which combines intelligent optimization algorithm with convex optimization algorithm. The improved grey wolf optimization (IGWO) algorithm is employed to optimize the positions of the array elements, while l_∞-norm is introduced to describe spatial response variation (SRV) for optimizing the finite impulse response (FIR) filter weights of the array. Considering multiple constraints, such as array aperture and minimum spacing between elements, an optimal trade-off among constant beamwidth, FI characteristics, and peak sidelobe level (PSL) is achieved. The effectiveness and advantages of this method are evidenced by synthesis examples of FI beam patterns for wideband NUSA in different application scenarios. These experimental results hold important theoretical significance, and provide valuable references for solving the optimization problem of wideband FI array under multiple constraints.

Design of Sparse Wideband Frequency-invariant Beamforming Based on Hybrid Grey Wolf-<I>l</I><sub>∞</sub>-norm Algorithm

2025-05-06

PIER C

Vol. 155, 137-146, 2025

doi:10.2528/PIERC25021809

download: 55

Arbitrary Shape Transmitting Coils Optimization for One-to-Many Free-Positioning Wireless Power Transfer Systems

Pavel Smirnov, Aleksandr Miroshnikov and Polina V. Kapitanova

Nowadays, misalignment tolerant wireless power transfer systems providing simultaneous power supply to several devices are the subject of intensive research in the field of wireless charging of electronic devices. A critical parameter in such systems is the uniformity of magnetic field generated by a transmitting coil. In this paper, we examine the characteristics of the magnetic field distribution of arbitrary shape planar transmitting coils and propose a genetic algorithm for optimizing their design with the objective of increasing the field uniformity. This study stands out from existing literature by introducing an optimization approach that not only encompasses traditional circular and square coils but also extends to convex polygonal coils. The results of the algorithm are validated experimentally on coils of three various geometries including circular, square, and hexagonal coils. The coefficient of variation of the magnetic field, which serves as a quantitative measure of its uniformity, is found to be 3.6% for circular coil, 5.2% for square one, and 5.1% for hexagonal one in a region of interest encompassing half of the total area of transmitting coil.

Arbitrary Shape Transmitting Coils Optimization for One-to-Many Free-positioning Wireless Power Transfer Systems

2025-05-06

PIER C

Vol. 155, 127-135, 2025

doi:10.2528/PIERC25031002

download: 151

High Isolation mm -Wave 8-Element MIMO Antenna for 5G Applications

Nayera Nahvi and Khalid Muzaffar

The present study describes the architecture of a defected ground structure (DGS)-based eight-element multiple-input multiple-output (MIMO) antenna. It functions in the millimeter-wave spectrum n258 (24.25–27.5 GHz) and is mainly intendedd for fifth-generation (5G) applications. Each antenna element has an elliptical slot at the ground plane and a hook-shaped antenna integrated into it to reduce the mutual coupling among the adjacent antenna elements. With a wide bandwidth of 5 GHz and an isolation level greater than 37 dB, the proposed antenna effectively covers the frequency range of 22.5 to 27.5 GHz. At the designated resonant frequency, it generates a directed radiation pattern and gain of 6.31 dBi. The proposed antenna's diversity system performance characteristics are assessed using metrics like channel capacity loss (CCL), diversity gain (DG), mean effective gain (MEG), and envelope correlation coefficient (ECC). The 8-port proposed MIMO antenna prototype, exhibiting overall dimensions of 62.7 × 31 × 0.787 mm³, has been constructed utilizing an economical FR4 substrate, demonstrating a substantial association between the computed and measured outcomes, thereby establishing its viability as a potential candidate for 5G communications.

High Isolation Mm-Wave 8-Element MIMO Antenna for 5G Applications

2025-05-05

PIER C

Vol. 155, 121-126, 2025

doi:10.2528/PIERC25040202

download: 26

Physics-Based 2D Direction Finding of an Amplitude Modulated Signal Using a Uniform Triangular Array

Kai Ren

A uniform triangular array (UTA) is proposed for physics-based 2D direction-of-arrival (DOA) estimations of unknown incoming signals. Three capacitively loaded top-hat antennas are used as array elements. Unlike conventional array-based direction finding (DF) systems, complex antenna radiation patterns are used in array manifold calculations and DOA predictions, where coupling among array elements is naturally resolved. Both continuous wave (CW) signals and single tone signals with amplitude modulation (AM) are considered in DF simulations. Cramer-Rao bound (CRB) values are calculated to provide theoretical lower bounds of DF accuracies. Multiple signal classification (MUSIC) algorithm is used to further demonstrate the DF performance of the triangular antenna array without any angle ambiguities within the field of view from 0˚ to 360˚ in the azimuth direction and from 1.25˚ to 178.75˚ in the elevation direction.

Physics-based 2D Direction Finding of an Amplitude Modulated Signal Using a Uniform Triangular Array

2025-05-04

PIER C

Vol. 155, 111-119, 2025

doi:10.2528/PIERC25031103

download: 45

Design of a Compact Dual-Band Metamaterial Bandpass Filter Using Multi-Type Fractal Geometries

Hayder S. Ahmed and Aqiel Na'ma Almamori

In this paper, a compact Dual-Band Bandpass Filter (BPF) has been proposed and designed based on two concepts. Firstly, transmission lines (TLs) feed the center resonators (CRs), which resonate at 11 GHz, while the metamaterial-based Center Resonators (CRs) resonate at 6 GHz for RF/Microwave applications. To miniaturize the planer structure, two different types of fractal geometry have been applied. First iteration modified-Minkowski fractal geometry has been applied on the CRs while the meander line with second order has been applied on the TLs. The proposed structure has been designed by using a Rogers RO4003 substrate with a thickness of 1.5 mm and a dielectric constant of 3.5. The simulation is implemented using CST microwave studio. To validate the proposed structure, the compact dual-band BPF is fabricated, and the measurements show high agreement with the simulation. Finally, the proposed structure achieves a 26 % reduction compared to the previous work.

Design of a Compact Dual-band Metamaterial Bandpass Filter Using Multi-type Fractal Geometries

2025-05-02

PIER C

Vol. 155, 103-110, 2025

doi:10.2528/PIERC25030503

download: 27

A Compact Quintuple-Mode Wideband Bandpass Filter Using Disk-Loaded Feeding Lines in a Single Cylindrical Cavity

Maha H. Elfeshawy, Hany Fathy Hammad and Yasmine Abdalla Zaghloul

This work presents a quintuple-mode wideband bandpass filter utilizing a cylinder cavity loaded with a metallic perturbation on each base and a gap between them. The cylindrical cavity is fed with two inline disk-loaded feeding lines placed in the middle of the cavity wall. Two inline shorting pins are placed orthogonally in the same feeding lines plane. The five resonant modes are: TM₀₁₁, TE₁₁₁, the degenerate modes of TE₂₁₁ and quasi-TE₃₁₁ excited by the pair of disk-loaded feeding lines and shorting pins. This combination allows the generation of two transmission zeros (TZs) out of the passband. The mode analysis and geometric configuration are well studied and presented in this work. The results of the quintuple-mode filter demonstrated a fractional bandwidth of 66.87% at a central frequency of 3.69 GHz with insertion loss 0.18 dB and return loss higher than 19.4 dB. The coupling matrix of the proposed filter is synthesized as a five-pole Chebyshev filter showing close alignment with the simulated results. Finally, the proposed bandpass filter is fabricated and measured for comparison. Close agreement is achieved between the simulated and measured results.

A Compact Quintuple-mode Wideband Bandpass Filter Using Disk-loaded Feeding Lines in a Single Cylindrical Cavity

2025-04-29

PIER C

Vol. 155, 95-102, 2025

doi:10.2528/PIERC24111405

download: 77

Reducing the Effect of Crosstalk in WDM-VLC Systems

Huda Faris Younus and Safwan Hafeedh Younu

Due to the rapid development of the internet and mobile communication needs, visible light communication (VLC) has become an attractive technique for indoor wireless communication. This research investigates how data rates in VLC systems are affected by the wavelength division multiplexing (WDM) technology. The WDM technique allows different data streams to be transmitted simultaneously over different wavelengths in the same optical channel. In WDM-VLC systems, the interference between channels known as crosstalk is a significant problem that may reduce the quality of communication. By optimizing the field of view (FOV) of the optical receiver and changing system parameters to reduce interference, this research resolves the crosstalk issue. With attention to the signal-to-interference-plus-noise ratio (SINR) and channel bandwidth, we use a simulated indoor environment to examine how line of sight (LOS) and non-line of sight (NLOS) elements affect the system performance. The results show that reducing the FOV leads to reducing the crosstalk and significantly enhancing data speeds and reliability in the system. Additionally, a review of practical challenges related to the implementation of different FOV lenses is presented, along with a comparative assessment of complexity, scalability, and cost in relation to present solutions. The results offer important updated knowledge on WDM's capabilities in VLC systems, enabling rapid transfer of data and efficient lighting for smart interior spaces.

Reducing the Effect of Crosstalk in WDM-VLC Systems

2025-04-29

PIER C

Vol. 155, 85-93, 2025

doi:10.2528/PIERC25010103

download: 58

Optimization Design of Axial Flux Permanent Magnet Synchronous Motor Based on Multi-Objective Genetic Algorithm

Huijun Liu

As a new type of motor, axial flux permanent magnet synchronous motor has the advantages of compact structure and high power density. It shows good application prospects in new energy vehicles, unmanned aerial vehicles, and other fields. However, axial flux permanent magnet synchronous motor needs to consider the balance of multiple objectives during the design process, which makes its optimal design a complex multi-objective optimization problem. Therefore, the study proposes a motor optimization method based on multi-objective genetic algorithm. The method optimizes the rotor and stator parameters of the motor by establishing an analytical model of the motor's magnetic field and combining it with a multi-objective genetic algorithm. The experimental results indicated that the optimized motor with multi-objective genetic algorithm reached 92% in terms of efficiency, 25% in terms of power density; energy consumption was reduced to 2.5 kWh; failure rate was reduced to 1.5%; and noise level was reduced to 65 dB. In addition, the multi-objective genetic algorithm significantly improved the control stability index, which increased to 98%, indicating a more stable motor response under varying loads. The disturbance rejection capability was enhanced to 99%, demonstrating strong resistance to external noise and parameter fluctuations. Furthermore, the system response frequency reached 100 Hz, reflecting a faster dynamic response to input variations. It is indicated that the optimization method based on multi-objective genetic algorithm can effectively enhance the comprehensive performance of axial flux permanent magnet synchronous motor and significantly improve its competitiveness in high power density and high efficiency applications.

Optimization Design of Axial Flux Permanent Magnet Synchronous Motor Based on Multi-objective Genetic Algorithm

2025-04-29

PIER C

Vol. 155, 75-83, 2025

doi:10.2528/PIERC25031204

download: 48

Investigation of Step-Skew Rotor on Electromagnetic Force and Vibration in Intergral-Slot IPMSM Driven with SVPWM Technique

Zhi Xu, Shunqing Xu, Dandan Liu and Zhishu Yao

This paper investigates the effects of the step-skew rotor on electromagnetic vibration performance of a 72-slot/12-pole interior permanent magnet synchronous machine (IPMSM) considering the carrier sideband current harmonics. Firstly, the effect of the step-skew rotor on carrier sideband current harmonics generated by the space vector pulse-width modulation technique is investigated. Second, the interaction electromagnetic field near the first carrier frequency of the 72-slot/12-pole IPMSM is analytically investigated. The effects of the step-skew rotor on the electromagnetic force at low-medium and carrier frequency domain are discussed. The force modulation effect is also considered to investigate the effects of the step-skew rotor on the 72nd-order force and the zeroth mode vibration. Finally, the vibration responses of two IPMSMs with and without the step-skew rotor are simulated to validate the suppression effect of this structure on the 72nd-order force. The simulation results demonstrate that the step-skew rotor design effectively reduces vibration acceleration by 75.7% at 12 times of the fundamental frequency and 30.4% at carrier sideband frequency.

Investigation of Step-skew Rotor on Electromagnetic Force and Vibration in Intergral-slot IPMSM Driven with SVPWM Technique

2025-04-28

PIER C

Vol. 155, 67-74, 2025

doi:10.2528/PIERC25021702

download: 93

Design of Polarization-Insensitive Wideband Metamaterial Radar Absorber with Enhanced Bandwidth

Muhammad Abuzar Baqir, Abdul Qadeer, Olcay Altintas, Muhammad Umer Draz, Muharrem Karaaslan and Jahariah Sampe

Metamaterial-based absorbers offering perfect and broadband absorption are greatly desirable in radar and stealth technology systems. Further, the polarization insensitive feature makes the absorber useful for industrial applications. This study examines the design of a wideband metamaterial-based radar absorber functioning throughout the frequency range of 8 to 16 GHz. The metasurface design comprises two concentric metallic rings and a fan-shaped circular metallic disc at the middle. The rings and the central disc are interconnected with surface-mounted chip resistors to enhance the absorption bandwidth. It is depicted that more than 90% absorptivity was attained from 8 to 16 GHz. A wideband absorber with angular stability and polarization insensitivity is an excellent choice for wireless communications, particularly in radar applications. Further, the measured results of the prototype corresponded well with the simulated outcomes.

Design of Polarization-insensitive Wideband Metamaterial Radar Absorber with Enhanced Bandwidth

2025-04-28

PIER C

Vol. 155, 61-66, 2025

doi:10.2528/PIERC25021807

download: 43

A New Method for Determining Antenna Gain via Transmission Line Based Near Field Measurements in a Waveguide

Daniel Richardson, James Dee, Jonathan Yaeger, Jeramy Marsh and Ryan S. Westafer

Antenna gain is an important metric for most modern communication systems. The most common method for determining antenna gain is to produce an incident plane wave using a reference antenna and measure the received power at the antenna of interest. By measuring the received power several wavelengths away in an isolated environment, such as an anechoic chamber, the gain of an electrically small antenna, dimension less than one wavelength, can be determined. This and other similar methods work well for frequencies above 2 GHz, but lower frequency measurements can be logistically challenging and expensive due to the large facilities required and the lack of readily available broadband absorber materials. This work presents a new method for determining antenna gain using a transmission-line-based near-field S-parameter measurement in a waveguide. To provide evidence for the proposed method, two monopole antennas are modeled over an infinite ground plane using full-wave electromagnetics, and both are experimentally measured within a waveguide. Good agreement was found between the model and measurement, providing evidence of the validity of the method.

A New Method for Determining Antenna Gain via Transmission Line Based Near Field Measurements in a Waveguide

2025-04-28

PIER C

Vol. 155, 53-60, 2025

doi:10.2528/PIERC25031401

download: 56

A Dual-Polarized Broadband Magneto-Electric Dipole Antenna Incorporating Parasitic Elements

Xinyi Li, Wu-Sheng Ji, Haibo Li and Jingbo Shi

This paper proposes a broadband dual-polarized (DP) magneto-electric dipole antenna (MEDA) loaded with parasitic elements. The antenna structure comprises a rectangular reflecting cavity, four corner-truncated and optimized horizontal electric dipoles, eight vertically arranged magnetic dipoles, and four triangular parasitic elements embedded in the truncated corners of the electric dipoles. An orthogonal Γ-shaped feeding network is employed to excite dual-polarized modes, ensuring stable bandwidth and gain performance. Experimental measurements demonstrate an overlapping impedance bandwidth (|S₁₁| and |S₂₂| ≤ -10 dB) of 84.7% (1.92-4.74 GHz) for both ports, with an in-band peak gain of 11.69 dBi and port isolation exceeding 27 dB. This design provides a compact high-isolation dual-polarized antenna solution for 5G multi-band communication systems.

A Dual-polarized Broadband Magneto-electric Dipole Antenna Incorporating Parasitic Elements

2025-04-26

PIER C

Vol. 155, 43-52, 2025

doi:10.2528/PIERC25031001

download: 46

Research on Lightning-Induced Transient Characteristics of Photovoltaic Power Generation Systems Based on CDEGS

Wen Cao, Xiaojun Tang, Yicheng Fan, Wei Shen, Bobo Chen and Jiarui Zhang

To address the quantification challenges of transient responses in direct lightning strike protection design for photovoltaic (PV) power generation systems, this study establishes an integrated coupled model using CDEGS simulation software, incorporating horizontally layered soil, PV mounting structures, and grounding systems. A comprehensive consideration of key factors, including lightning current waveforms, soil resistivity, and the number of down conductors and vertical grounding electrodes, enables quantitative analysis of transient overvoltage and transient ground potential rise (TGPR) distribution characteristics under varying operating conditions. The results demonstrate that both soil resistivity and lightning current waveforms are critical factors influencing the transient lightning-induced characteristics of PV systems. In typical low-resistivity (ρ = 200 Ω.m) and high-resistivity (ρ = 2000 Ω.m) soil environments, increasing the number of grounding down conductors and vertical grounding electrodes can both reduce induced overvoltage and transient ground potential rise. However, beyond a certain threshold, shielding effects between adjacent grounding bodies limit current dissipation efficiency, leading to diminishing returns. Therefore, PV system lightning protection design must holistically account for soil properties, lightning current parameters, and optimized layout strategies to mitigate transient amplitudes, achieving an optimal balance between lightning protection effectiveness and economic efficiency.

Research on Lightning-induced Transient Characteristics of Photovoltaic Power Generation Systems Based on CDEGS

2025-04-26

PIER C

Vol. 155, 37-42, 2025

doi:10.2528/PIERC25022005

download: 28

Revealing the Spatial Distribution of Radiation Emitted by Simple Objects

Edmund K. Miller

This article summarizes the author's work over the years having the goal of developing computational tools for deter-mining the quantitative distribution of where radiation is emitted from objects of interest.

Revealing the Spatial Distribution of Radiation Emitted by Simple Objects

2025-04-25

PIER C

Vol. 155, 29-35, 2025

doi:10.2528/PIERC25022602

download: 62

Efficient High-Precision Classification Algorithm for Radar Deceptive Jamming via Array Detection

Wenjie Liu, Wenfang Qin, Mingwei Shen and Guodong Han

In complex electromagnetic scenarios where multiple deceptive jamming signals are simultaneously aliased in the timefrequency domain, conventional single-channel electronic detection systems struggle to effectively separate and classify overlapping jamming sources. To address this limitation, this paper investigates an array detection-based classification scheme for multi-source jamming. First, due to the spatial degrees of freedom offered by array systems, the Direction-of-Arrival (DOA) of each jamming source is precisely estimated using the MUSIC algorithm. Then, the adaptive digital beamforming (ADBF) filters are designed based on the estimated DOA parameters, enabling spatial-domain extraction of individual jamming signals. Finally, the DOA information is integrated into the Pulse Description Word (PDW) of each separated jamming measurement, which can facilitate adaptive K-Means clustering with enhanced class separability. Simulation results demonstrate that the proposed method achieves a 22.4% improvement in classification accuracy compared to existing single-channel detection approaches, while maintaining computational efficiency.

Efficient High-precision Classification Algorithm for Radar Deceptive Jamming via Array Detection

2025-04-24

PIER C

Vol. 155, 19-28, 2025

doi:10.2528/PIERC25030302

download: 52

Minimum-Current-Stress Strategy for Modular Multilevel Type DC-DC Converter Based on Long Short-Term Memory Optimization

Dazhuan Yu, Xin Chow, Zefeng Lin and Xiaobing Niu

Current stress has a significant impact on the operation of power electronic devices, and the reduction of current stress can improve the safety and reliability of the system. First, this paper proposes a novel asymmetric duty cycle modulation strategy for the primary side of a modular multilevel type (MMC) dual active bridge converter (DAB) to increase the control freedom of the primary side. Secondly, a novel optimization strategy based on a long-short-term memory network (LSTM) classification is proposed in this paper to optimize the current stress. The output power of the system is classified by LSTM，and minimum current stresses at different powers are optimized by a novel meta-heuristic iterative optimization based on generalized quadratic interpolation (GQI). Finally, the feasibility of the scheme is verified by hardware-in-the-loop experiments.

Minimum-current-stress Strategy for Modular Multilevel Type DC-DC Converter Based on Long Short-term Memory Optimization

2025-04-23

PIER C

Vol. 155, 11-18, 2025

doi:10.2528/PIERC24112104

download: 54

Integrated Generator Design for Double Stator Hybrid Excitation Flux Switching Machine

Nur Afiqah Mostaman, Erwan Bin Sulaiman, Mahyuzie Jenal and Irfan Ali Soomro

Double Stator Hybrid Excitation Flux Switching Generator (DS-HEFSG) has attracted significant interest in power-generating research owing to its potential for improved performance and sustainability. This research examines the utilization of hybrid excitation to enhance the efficiency of a three-phase DS-HEFSG specifically engineered for low-speed power applications such as renewable energy systems like wind and tidal turbines. The innovative method presents a double stator hybrid configuration for a traditional double stator generator, with performance evaluation performed via 2D finite element simulations. The findings indicate that the DS-HEFSG surpasses traditional topologies, rendering it an optimal selection for this generator configuration. The proposed design significantly increases the 18.76% cogging torque value while the electromotive force increases by approximately 21.62%. The proposed design also decreases permanent magnet eddy-current losses by 24.33%. Enhanced performance is noted in electromagnetic torque, torque ripple, output power, and overall efficiency. These advancements contribute to energy savings and lower maintenance costs, reducing reliance on fossil fuels and supporting the transition to greener energy solutions. The proposed DS-HEFSG with hybrid excitation is a viable alternative for efficient low-speed power production.

Integrated Generator Design for Double Stator Hybrid Excitation Flux Switching Machine

2025-04-22

PIER C

Vol. 155, 1-9, 2025

doi:10.2528/PIERC25021705

download: 68

Ternary B2O3-TeO2 -BaO Glass as a Shielding Case

Samar M. Ibrahim, Yara Abdelghany, Maged M. Kassab, Mostafa M. Radwan and Ahmed Abdel-Latif M

This study investigates the properties of a ternary B₂O₃-TeO₂-BaO glass system, prepared through the melt-quenched technique. The chemical formula used is (50 - x/2)B₂O₃ + (50 - x/2)TeO₂ + xBaO, with x varying from 15 to 35 mol.%. The research explores how the gamma and neutron radiation shielding capabilities were analyzed. It finds that higher BaO content enhances gamma-ray shielding but does not significantly affect neutron shielding. The glass sample BTB35 emerged as the optimized candidate among the developed samples for gamma radiation shielding applications. Also, the obtained results for the MFP was compared to commercial shielding glasses, and other measurements on glasses show the superiority of BTB35 as commercial transparent radiation shielding glass.