PIER B | PIER Journals

2024-01-25

PIER B

Vol. 104, 171-186, 2024

download: 188

Vibro-Acoustic Analysis for Transformer Under DC Bias Based on Electromagnetic Coupling

Chao Pan , Xiaobo Shi , Tongrui Fu and Jingge An

Aiming at the operational stability of DC-biased transformer, a multi-parameter correlation method based on electromagnetic coupling is presented in this paper. The mode-state analysis scheme is designed, and the feature parameters of electromagnetic, mechanical, and acoustic fields in internal components are simulated and analyzed. The electromagnetic properties under DC bias are simulated by the electromagnetic model, thus the winding current and magnetic flux density are extracted as the feature parameters. Then the vibration and stress distribution can be solved by the mechanical model, which are treated as the feature parametersof the mechanical field. By utilizing the computed mechanical information as excitation, the spatial-temporal distribution of sound pressure can be obtained in the acoustic model. Taking three-phase three-limb transformer and three-phase group transformer as examples, the electromagnetic, mechanical, and acoustic parameters of components are analyzed under different conditions. The variations of feature parameters are summarized and contrasted. Furthermore, actual vibration and noise parameters are measured through dynamic experimental platforms. The effectiveness of the multi-parameter correlation method is verified by the consistency between simulation and experiments, and the unobservable abnormal physical features can be represented by observable electrical information.

Vibro-acoustic Analysis for Transformer under DC Bias Based on Electromagnetic Coupling

2024-01-22

PIER B

Vol. 104, 147-169, 2024

doi:10.2528/PIERB23102401

download: 742

Millimeter Wave Antennas: a State-of-the-Art Survey of Recent Developments, Principles, and Applications

Reena Aggarwal , Ajay Roy and Rajeev Kumar

The increasing volumes of data generated by social networking, cloud computing, e-commerce, and online video broadcasting necessitate the implementation of higher data rates. As the current 4G network encounters congestion and potentially struggles to accommodate the substantial data demand, there is a growing interest in millimeter wave (mmWave) technology. The 30-300 GHz mmWave spectrum is characterized by its broad bandwidth and low latency; it is having many applications in communication domains, also includes 5G cellular. Despite its atmospheric attenuation and non-line-of-sight (NLOS) propagation, the majority of nations have begun to implement mmWave 5G in the band of 28/38 GHz as a result of its reduced path loss exponent, minimal signal spread, and decreased atmospheric attenuation. While the patch antenna (single-element) is a compact and easily transportable choice for mmWave applications, its radiation efficiency, gain, and bandwidth are all subpar. Array antennas have effectively addressed these limitations by exhibiting significant enhancements in bandwidth, gain, and radiation efficiency. It is still limited in the maximum data rates it can accommodate. The rate of data can be increased by a factor of one thousand using Multiple-Input-Multiple-Output (MIMO) technology, which is enabled by geographical diversity and multiplexing techniques. As a result, comprehension of the structures of MIMO antennas operating at mmWave is imperative for the continued enhancement of performance. In comparing the efficacy of these designs, bandwidth, isolation, efficiency, gain, and radiation pattern are considered. In this paper, the most recent planar MIMO antenna designs, which are categorized as defected ground structures, Slot/Patch/Stub, MIMO Antenna Array, Dielectric Resonator Antenna, and Meta-Surface/Metamaterial Structures, are described. This paper also addresses the effects that slots, partial ground, and decoupling structures have on levels of isolation, bandwidth, and impedance matching. A comprehensive analysis of the design considerations and subsequent advancements is also provided in this paper.

Millimeter Wave Antennas: A State-of-the-Art Survey of Recent Developments, Principles, and Applications

2024-01-18

PIER B

Vol. 104, 131-146, 2024

doi:10.2528/PIERB23110206

download: 242

Enhancing Performance of Photovoltaic Pump Systems in Remote Areas Using a Sliding Mode Technique for Maximum Power Point Tracking

Alaa Shakir Mahmood

Photovoltaic (PV) systems represent an extremely intriguing alternative in order to provide dry and semi-arid regions in remote locations with water. In this case, a maximum power point tracking (MPPT) unit that aims to regulate the (PV) panel connected converter duty cycle is necessary to ensure that it operates as efficiently as possible under various operating situations. This study introduces a sliding mode technique-based MPPT control unit with the goal of enhancing photovoltaic pump (PVP) system performance. It discusses this for a number of scenarios, including the presence or absence of batteries, operation under various radiation conditions, and operation in consideration of constant speed and variable load torque. The outcomes of the MATLAB simulation demonstrated that the proposed methodology is preferable compared to the incremental conductance method for the various scenarios, and it achieves better efficiency and lower voltage ripples.

Enhancing Performance of Photovoltaic Pump Systems in Remote Areas Using a Sliding Mode Technique for Maximum Power Point Tracking

2024-01-17

PIER B

Vol. 104, 109-129, 2024

doi:10.2528/PIERB23112603

download: 308

Metamaterial-Based Octagonal Ring Penta-Band Antenna for Sub-6 GHz 5G, WLAN, and WiMAX Wireless Applications

Rishi Parasher , Dinesh Yadav and Ankur Saharia

In this article, a metamaterial SRR and CSRR based octagonal ring-shaped multiband antenna is presented. The proposed antenna structure is designed with the implementation of slotted radiating patch with metamaterial cells for resonating at penta-bands to cover the 5G Sub-6 GHz NR frequency bands n48/n78/n79/n96, 3.5 GHz worldwide interoperability for microwave access, 5 GHz wireless local area network, 10.03-14.29 GHz upper X band and 15.74-19.98 GHz upper Ku band wireless applications. The proposed antenna with a compact dimension of 33×22×1.6 mm³ is fabricated to validate the simulated results with measured ones. The radiation characteristics is identified in stable and uniform manner for all the penta resonant bands.

Metamaterial-based Octagonal Ring Penta-band Antenna for Sub-6 GHz 5G, WLAN, and WiMAX Wireless Applications

2024-01-13

PIER B

Vol. 104, 91-108, 2024

doi:10.2528/PIERB23111504

download: 535

A Review of the Advancement of Metasurfaces in Wearable Antenna Design for off -Body Communications

Nibash Kumar Sahu , Naresh Chandra Naik , Madhab Chandra Tripathy and Sanjeev Kumar Mishra

This review article explores the advancement of metasurfaces in wearable antenna design for off-body communications. The wearable antenna needs to be compact, flexible, and, most importantly, should have less back radiation. In this context, wearable antennas that are inspired by metasurfaces are a good choice. Metasurface can make the antenna compact and reduce the back-radiated waves, which lowers the specific absorption rate (SAR) and improves the antenna's performance. In addition, the metasurface can also generate circular polarization (CP) by carefully rotating the electromagnetic (EM) waves incident on it and multi-band by simultaneously exciting its multiple modes. Using the aforementioned features provided by the metasurface, the surveys are segregated as single-band with linear polarizations (LP), single-band with CP, dual-band with LP, dual-band with dual polarization, and dual-band with dual CP. Prior to the survey, the challenges and considerations for wearable antenna design as well as the theoretical perspective behind performance improvements are discussed. Also, a conventional unit-cell of the metasurface is theoretically designed using the discussed theories and validated using CST Microwave Studio, which shows good agreement with each other.

2023-12-18

PIER B

Vol. 104, 69-89, 2024

doi:10.2528/PIERB23101904

download: 907

Design Challenges and Solutions of Multiband MIMO Antenna for 5G/6G Wireless Applications: a Comprehensive Review

Usha Sharma , Garima Srivastava , Mukesh Kumar Khandelwal and Rashmi Roges

A comprehensive review of multiband MIMO antennas designed for wireless applications in the 5th and 6th generation (5G and 6G) networks is presented. The demand for higher data rates and improved spectral efficiency in advanced wireless networks continues growing, and multiband MIMO antenna systems have emerged as a promising solution. This review aims to provide an in-depth analysis of the existing literature on multiband MIMO antennas for 5G and 6G wireless applications. The paper's main objectives are: (1) to emphasize the requisite of MIMO antenna for the sub-6 GHz of 5G/6G wireless communication, (2) to explore and evaluate the various design approaches to target 5G/6G frequencies, (3) To demonstrate various techniques to generate multiband, (4) To highlight the challenges and their potential solutions to design multiband MIMO for 5G/6G. (5) To investigate the methods to attain circular polarization (CP) and pattern diversity for better system performance. The review critically analyzes the latest advancements, challenges, and future research directions for multiband MIMO antennas in the context of 5G and 6G wireless networks. This comprehensive review serves as a valuable resource for researchers, engineers, and practitioners seeking a deeper understanding of multiband MIMO antennas and their potential to support the demands of the ever-evolving wireless communication technology.

Design Challenges and Solutions of Multiband MIMO Antenna for 5G/6G Wireless Applications: A Comprehensive Review

2023-12-07

PIER B

Vol. 104, 51-68, 2024

doi:10.2528/PIERB23062902

download: 173

Advanced Analysis of Radar Cross-Section Measurements in Reverberation Environments

Corentin Charlo , Stéphane Méric , François Sarrazin , Elodie Richalot , Jérome Sol and Philippe Besnier

Reverberation chambers (RCs) were recently reported as a low-cost alternative to anechoic chambers (ACs) to perform radar cross-section (RCS) pattern measurements. The method consists i, using transmitting and receiving antennas pointing towards a target under test placed on a rotating mast. As a classical RCS characterization, the echo signal is analysed based on two measurements with and without the target in the RC. In the hypothesis of an ideal diffuse field generated in the RC, this signal difference appears as the echo signal hidden in a Gaussian noise. In case of a point-like backscattering target, observing this signal over a given frequency bandwidth allows the identification of the target response as a sinusoidal signal over this bandwidth whose period is related to the antenna-target distance measured from the measurement calibration plane positions. Therefore, the extraction of the magnitude of this sinusoidal signal requires a proper estimation of this distance. Furthermore, a sinusoidal regression processing relies on the approximation of a constant envelope over the selected frequency bandwidth, imposing some restrictions. In this paper, we introduce a two-step method that consists in identifying the most appropriate distance according to the target's orientation before estimating the magnitude of the sinusoidal signal. We highlight the improvement of RCS estimation on a point-like back-scattering target compared to the one-step procedure applied so far. In addition, it is shown that the analysis performed regarding the estimated distance provides a physical insight into the position of the equivalent backscattering point.

Advanced Analysis of Radar Cross-section Measurements in Reverberation Environments

2023-12-07

PIER B

Vol. 104, 35-50, 2024

doi:10.2528/PIERB23071501

download: 240

Effect of via-Array Side Walls on the Characteristics of SIW Resonator with Novel Design Equations

Samar M. Azab , Abdelhameed Abdelmoneim Shaalan , Khalid Fawzy Ahmed Hussein and Asmaa Elsayed Farahat

The present work proves by both simulation and experimental work that the most common empirical formulas available in the previous publications for the design of substrate-integrated waveguide (SIW) cavities are incorrect in most cases. Moreover, the present work provides correct and exact design equations that are examined by both simulation and experimental work. In planar circuit structures, rectangular waveguide and resonators are commonly integrated within a dielectric substrate to produce what is known as SIW structures. For ease of fabrication and embedding into the dielectric substrate, the closed (solid) side walls of the rectangular waveguides and resonators are replaced by metallic via arrays. The main concern of the present paper is to investigate the effects of such replacement on the performance of a SIW resonator through simulation as well as experimental work. The limiting constraints on the relative dimensions of such via arrays including the diameter of the vias and the spacing between them are numerically and experimentally investigated to ensure proper operation of the SIW resonator regarding the radiation loss due to leakage from the openings of the resonator side walls. The effects of the via array dimensions on the resonant frequency, radiation loss, and quality factor (Q-factor) of the resonator are evaluated. For this purpose, two models of the rectangular resonator embedded in the dielectric substrate are designed to operate at 10 GHz. The first model is an ideal box-shaped resonator of solid side walls whereas the other model is the conventional SIW resonator with via-array side walls. The two types of the substrate embedded resonators are fed through a microstrip line. The resonant frequency, losses, and Q-factor of the two resonator models are compared to each other taking the box-shaped resonator as a reference because of its ideal structure to evaluate the performance of a conventional SIW resonator. The two types of resonator are fabricated for comparison through experimental measurements. The empirical design equations that are commonly available in literature to calculate the effective dimensions of the SIW resonator are investigated by comparison with the exact simulation results and shown to be incorrect in most cases. More accurate and reliable design equations are proposed in the present work. The results of the proposed design equations are compared to the simulation results showing excellent accuracy and shown to be more reliable than those available in literature.

Effect of Via-array Side Walls on the Characteristics of SIW Resonator with Novel Design Equations

2023-11-29

PIER B

Vol. 104, 21-33, 2024

doi:10.2528/PIERB23091305

download: 290

The Influence of Contrast and Temporal Expansion on the Marching-on-in-Time Contrast Current Density Volume Integral Equation

Petrus Wilhelmus Nicolaas (Pieter) Van Diepen , Martijn Constant van Beurden and Roeland Johannes Dilz

The contrast current density volume integral equation, discretized with piecewise constant spatial basis and test functions and Dirac-delta temporal test functions and the piecewise polynomial temporal basis functions, results in a causal implicit marching-on-in-time scheme that we refer to as the marching-on-in-time contrast current density volume integral equation (MOT-JVIE). The companion matrix stability analysis of the MOT-JVIE solver shows that for a fixed spatial and temporal step size, the stability is independent of the scatterer's dielectric contrast for quadratic spline temporal basis functions. Whereas, Lagrange and cubic spline exhibit instabilities at higher contrast. We relate this stability performance to the expansion and testing procedure in time. We further illustrate the capabilities of the MOT-JVIE based on quadratic spline temporal basis functions by: comparing the MOT-JVIE solution to time-domain results from literature and frequency-domain results from a commercial combined field integral equation solver. Finally, we present a long time sequence for a high-contrast scatterer discretized with 24,000 spatial unknowns.

The Influence of Contrast and Temporal Expansion on the Marching-on-in-Time Contrast Current Density Volume Integral Equation

2023-11-24

PIER B

Vol. 104, 1-19, 2024

doi:10.2528/PIERB23060902

download: 312

BI-CMOS Design of a*exp (-j *φ0) Phase Shifter as Miniature Microwave Passive Circuit Using Bandpass NGD Resonant Circuit

Mathieu Guerin , Fayrouz Haddad , Wenceslas Rahajandraibe , Samuel Ngoho , Glauco Fontgalland , Fayu Wan and Blaise Ravelo

The purpose of this paper is to study the RF/microwave constant phase shift (CPS) designed as an integrated circuit (IC) in 130-nm Bi-CMOS technology. The CPS understudy is constituted by a bandpass (BP) negative group delay (NGD) passive cell combined in cascade with a positive group delay (PGD) circuit. The CPS real circuit is represented by a CLC-network associated in cascade with a BP-NGD passive cell. The CPS characterization is based on the S-parameter modelling. The CPS is analytically modeled by the frequency independent transmission phase modelling by the mathematical relation φ(f)=a*exp(-j*φ₀) = constant around working frequency [f_n-Δf/2, f_n+Δf/2] by denoting center frequency f_n and frequency band Δf. The analytical principle of the constant PS is explored by means of the RLC-network based NGD cell. The design formula of the NGD and CLC passive circuit parameters in function of desired operation frequency is established. The validity of the developed theory is verified with a proof-of-concept (POC). A CPS miniature IC having physical size 1.15 mm × 0.7 mm is designed and implemented as POC in 130-nm Bi-CMOS technology. The ADS® and layout versus schematic of Cadence® simulation results from 130-nm Bi-CMOS CPS POC confirms the theoretical investigation feasibility. The simulated results of the obtained CPS IC POC layout show φ₀=-67°+/-1° phase shift around f_n=0.85 GHz within the frequency band delimited by f₁=0.73 GHz to f₂=0.984 GHz or Δf=f₂-f₁=254 GHz. The CPS robustness designed in 130-nm Bi-CMOS IC technology is stated by Monte Carlo statistical analysis from 1000 trials with respect to the component geometrical parameters. It was reported that the phase shift and insertion loss flatness's of the CPS IC is guaranteed lower than 5% in Δf/f_n=30% relative frequency band around f_n.