Submit to Electronics Review for Electronics Propose a Special Issue

Journal Browser

Microwave Devices Design and Application

Print Special Issue Flyer
Special Issue Editors
Special Issue Information
Published Papers

A special issue of Electronics (ISSN 2079-9292). This special issue belongs to the section "Microwave and Wireless Communications".

Deadline for manuscript submissions: closed (31 August 2021) | Viewed by 37151

Share This Special Issue

Special Issue Editor

Dr. Amir Ebrahimi

E-Mail Website
Guest Editor

School of Engineering, RMIT University, Melbourne, VIC 3001, Australia
Interests: metamaterials; RF/microwave sensors; microwave circuits; frequency-selective surfaces (FSSs); microwave engineering
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues:

James Clerk Maxwell was the first to predict the existence of invisible electromagnetic waves in 1865 using his famous formulas called “Maxwell’s equations”. For the first time, Heinrich Hertz demonstrated the existence of such electromagnetic waves by building an apparatus that produced and detected microwaves in the ultra-high-frequency region in 1888. Hertz’s experiment validated Maxwell’s prediction, but he did not see any practical applications for these invisible waves. Later work by others led to the invention of wireless communications based on microwaves. The microwave frequency range covers a broad spectrum from megahertz up to terahertz regimes. Although the primary application of microwave technology has been wireless communications, new technologies and applications have evolved over time. At present, microwave technology covers a broad range of applications including wireless communications, radar systems, wireless sensing and detection, biomedical health monitoring, etc. This Special Issue will to cover the recent findings and advances in the theory and design of microwave devices and components.

The topics of interest include but are not limited to:

Passive components (filters, couplers, transitions, waveguides, etc.);
Active components (amplifiers, mixers, oscillators, etc.);
RF packaging and package modelling;
RF MEMS and microsystems;
Microwave, millimeter-wave, and terahertz systems;
Radar, SAR, and microwave imaging;
Emerging areas (nanotechnology, biomedical applications, etc.);
Wireless and cellular architectures, circuits, and components;
Transmitter components;
Receiver components;
Antennas and phased arrays;
MIMO antennas;
Sensors and RFID;
Signal generation and modulation circuits;
Wireless power transfer.

Dr. Amir Ebrahimi
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Electronics is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Published Papers (12 papers)

Download All Papers

Research

10 pages, 2555 KiB

Open AccessFeature PaperArticle

A 6 GHz Integrated High-Efficiency Class-F⁻¹ Power Amplifier in 65 nm CMOS Achieving 47.8% Peak PAE

by Syed Muhammad Ammar Ali and S. M. Rezaul Hasan

Electronics 2021, 10(20), 2450; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics10202450 - 09 Oct 2021

Viewed by 2166

Abstract

This paper reports a “single-transistor” Class-F⁻¹ power amplifier (PA) in 65 nm CMOS, which operates at the microwave center frequency of 6 GHz. The PA is loaded with a Class-F⁻¹ harmonic control network, employing a new “parasitic-aware” topology deduced using a novel iterative algorithm. A dual-purpose output matching network is designed, which not only serves the purpose of output impedance matching, but also reinforces the harmonic control of the Class-F⁻¹ harmonic network. This proposed PA yields a peak power-added efficiency (PAE) of 47.8%, which is one of the highest when compared to previously reported integrated microwave/millimeter-wave PAs in CMOS and SiGe technologies. The amplifier shows a saturated output power of 14.4 dBm along with an overall gain of 13.8 dB. Full article

(This article belongs to the Special Issue Microwave Devices Design and Application)

► Show Figures

Figure 1

10 pages, 7869 KiB

Open AccessFeature PaperArticle

A New Analytical Design Methodology for a Three-Section Wideband Wilkinson Power Divider

by Asif I. Omi, Zeba N. Zafar, Hussain Al-Shakhori, Aubrey N. Savage, Rakibul Islam, Mohammad A. Maktoomi, Christine Zakzewski and Praveen Sekhar

Electronics 2021, 10(19), 2332; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics10192332 - 23 Sep 2021

Cited by 5 | Viewed by 2495

Abstract

In this paper, a new analytical design technique for a three-section wideband Wilkinson power divider is presented. The proposed design technique utilizes the dual-frequency behavior of commensurate transmission lines for the even-mode analysis and contributes a set of completely new and rigorous design equations for the odd-mode analysis. Measurement of a fabricated prototype utilizing the proposed technique shows an excellent return-loss (>16 dB), insertion loss (<3.35 dB), and excellent isolation (>22.7 dB) over 104% fractional bandwidth extending beyond the minimum requirements. Full article

(This article belongs to the Special Issue Microwave Devices Design and Application)

► Show Figures

Figure 1

12 pages, 3503 KiB

Open AccessFeature PaperArticle

Terahertz High-Q Absorber Based on Holes Array Perforated into a Metallic Slab

by Saeedeh Barzegar-Parizi and Amir Ebrahimi

Electronics 2021, 10(15), 1860; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics10151860 - 02 Aug 2021

Cited by 13 | Viewed by 2009

Abstract

In this paper, we theoretically analyze and design a dual-narrowband terahertz (THz) absorber based on a hole array drilled into a metallic slab. A very high-quality factor (Q) is achieved at both of the resonance frequencies. A circuit model-based approach is developed for the analysis and design of the proposed absorber. The absorption peaks occur at 2.46 and 3.75 THz frequencies with 98% and 96% absorptions at normal incidence, respectively. The achieved quality factors are 149 and 144, at 50% absorbance for the two absorption bands, respectively. Full article

(This article belongs to the Special Issue Microwave Devices Design and Application)

► Show Figures

Figure 1

8 pages, 2216 KiB

Open AccessCommunication

An Intrinsically Switched Tunable CABW/CFBW Bandpass Filter

by Tiejun Du, Boran Guan, Pengquan Zhang, Yue Gu and Dujuan Wei

Electronics 2021, 10(11), 1318; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics10111318 - 31 May 2021

Cited by 5 | Viewed by 1784

Abstract

In this paper, a novel intrinsically switched tunable bandpass filter based on a dual-mode T-shaped varactor-loaded resonator is presented. The varactors loaded in the T-shaped resonator are capable of efficiently tuning the resonant frequencies of the even and odd modes, as well as the transmission-zero frequency. Without any additional RF switches, the passband of the filter can be intrinsically switched off by adjusting the transmission zero to the resonant frequencies. In the switch-on state, the constant absolute bandwidth (CABW) or constant fractional bandwidth (CFBW) passband can be achieved by controlling the frequency space between the two resonances. For a demonstration, a 0.8–1.1 GHz intrinsically switched tunable bandpass filter with 74 MHz CABW or 8.5% CFBW was fabricated and tested. In the whole operating band with |S₁₁| < 10 dB, the insertion losses for CABW and CFBW are better than 3.3 dB and 3 dB, respectively, and the isolations are better than 20 dB in the switch-off state. The measured results have a good agreement with simulated results, which verifies the design theory. Full article

(This article belongs to the Special Issue Microwave Devices Design and Application)

► Show Figures

Figure 1

12 pages, 5567 KiB

Open AccessArticle

Temperature-Sensitivity of Two Microwave HEMT Devices: AlGaAs/GaAs vs. AlGaN/GaN Heterostructures

by Mohammad Abdul Alim, Abu Zahed Chowdhury, Shariful Islam, Christophe Gaquiere and Giovanni Crupi

Electronics 2021, 10(9), 1115; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics10091115 - 09 May 2021

Cited by 13 | Viewed by 3503

Abstract

The goal of this paper is to provide a comparative analysis of the thermal impact on the microwave performance of high electron-mobility transistors (HEMTs) based on GaAs and GaN technologies. To accomplish this challenging goal, the relative sensitivity of the microwave performance to changes in the ambient temperature is determined by using scattering parameter measurements and the corresponding equivalent-circuit models. The studied devices are two HEMTs with the same gate width of 200 µm but fabricated using different semiconductor materials: GaAs and GaN technologies. The investigation is performed under both cooled and heated conditions, by varying the temperature from −40 °C to 150 °C. Although the impact of the temperature strongly depends on the selected operating condition, the bias point is chosen in order to enable, as much as possible, a fair comparison between the two different technologies. As will be shown, quite similar trends are observed for the two different technologies, but the impact of the temperature is more pronounced in the GaN device. Full article

(This article belongs to the Special Issue Microwave Devices Design and Application)

► Show Figures

Figure 1

15 pages, 2940 KiB

Open AccessArticle

Double Slot Antenna for Microwave Thermal Ablation to Treat Bone Tumors: Modeling and Experimental Evaluation

by Citlalli Jessica Trujillo-Romero, Lorenzo Leija-Salas, Arturo Vera-Hernández, Genaro Rico-Martínez and Josefina Gutiérrez-Martínez

Electronics 2021, 10(7), 761; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics10070761 - 24 Mar 2021

Cited by 17 | Viewed by 2544

Abstract

According to statistics of the American Cancer Society, the number of young people diagnosed with bone tumors is growing. Surgery and radiotherapy are the common treatments, however they have several side effects which affect the patient’s life. Therefore, a cheaper and less side-effect therapy called thermal ablation has been explored. The goal of this paper is to measure the therapeutic temperatures and the viability of a double slot antenna designed to treat bone tissue by microwave ablation. The antenna (at an operating frequency of 2.45 GHz) was designed, modeled, constructed, and experimentally evaluated. The finite element method was used to predict the antenna performance by means of 2D axisymmetric models. The modeling parameters were used to build the antenna. The experimental evaluation shows that the antenna behavior is repeatable and the standing wave ratio (SWR) was around 1.5–1.8. Temperatures around 60–100 °C were achieved over the bone tissue. The antenna insertion modifies the antenna performance. An insertion lower than 3.5 cm is not recommended because the convection effects modified the tissue temperature. The thermal patterns showed a heat focus near to the slots, which makes it possible for use in the treatment of small tumors. Full article

(This article belongs to the Special Issue Microwave Devices Design and Application)

► Show Figures

Figure 1

10 pages, 4454 KiB

Open AccessArticle

Analysis of the Resonator Part of a Ka-Band Multiple-Beam Extended-Interaction Oscillator through Electric Field Uniformity

by Yu Qin, Yong Yin, Che Xu, Tongbin Yang, Qingyun Chen, Xiaotao Xu, Jie Xie, Liangjie Bi, Bin Wang, Hailong Li, Xuesong Yuan and Lin Meng

Electronics 2021, 10(3), 276; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics10030276 - 25 Jan 2021

Cited by 1 | Viewed by 1359

Abstract

The development of multiple-beam devices is required due to the increasing demand of compact, high-frequency, and high-power vacuum devices. A Ka-band multiple-beam extended-interaction oscillator which operates in TM₀₁ mode with a large diameter (as the value is 14.6 mm which is larger than the operating wavelength of 8 mm) to obtain high output power has been put forward. In previous studies, the performance differences of single-beam extended-interaction oscillator with different electric field uniformity can be as high as 70%. Simulation results predicted the multiple-beam device has an average output power of 7.594 kW when a total beam of 3 A, 18 kV and the uniformity parameter is 0.064. Meanwhile, it predicted that the difference of output power of multiple-beam devices with different field uniformity (corresponding uniformity parameter is within 0.064~0.278) is within 2.53% when other operating conditions are unchanged. The results show that the multiple-beam device substantially decreases the influence of the field uniformity, which is an important factor for the performance in the single-beam device. A cold test experiment has been carried out based on perturbation theory to obtain the electric field distribution curves of this device, and this provides a method for studying multiple-beam devices. Full article

(This article belongs to the Special Issue Microwave Devices Design and Application)

► Show Figures

Figure 1

20 pages, 6882 KiB

Open AccessArticle

Wideband Rectangular Waveguide to Substrate Integrated Waveguide (SIW) E-Plane T-Junction

by Roberto Vincenti Gatti, Riccardo Rossi and Marco Dionigi

Electronics 2021, 10(3), 264; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics10030264 - 23 Jan 2021

Cited by 2 | Viewed by 2147

Abstract

A broadband rectangular waveguide to substrate integrated waveguide power divider for hybrid beam forming networks is presented. Rectangular waveguide symmetric E-plane irises are used to realize a multi-section matching network. A hybrid circuit and full-wave design procedure are described and adopted to synthesize three matching networks with one, two, and three irises, progressively increasing the bandwidth and exceeding the state of the art in the last two cases. Three proof-of-concept prototypes are manufactured and tested to validate the design procedure. Good agreement between simulated and measured performance confirms the validity of the proposed solution. Full article

(This article belongs to the Special Issue Microwave Devices Design and Application)

► Show Figures

Figure 1

11 pages, 2475 KiB

Open AccessArticle

An Improved Stopband Dual-Band Filter Using Quad-Mode Stub-Loaded Resonators

by Min-Hang Weng, Chun-Yueh Huang, Shi-Wei Dai and Ru-Yuan Yang

Electronics 2021, 10(2), 142; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics10020142 - 11 Jan 2021

Cited by 11 | Viewed by 1720

Abstract

In this paper, we present a dual-band microstrip bandpass filter (BPF) with an improved stopband, which was constructed by a quad-mode stub-loaded resonator (SLR). Since the SLR is able to produce multiresonance within a single unit, the area saving is significant. The proposed quad-mode SLR was implemented by two stubs allocated at symmetry places, thus the even-/odd-mode can be applied to analysis the resonance. Moreover, to shift the spurious passband, the step impedance structure was applied to shift the harmonic resonance to the higher frequency. Design procedure for high performance dual-band BPF is proposed, and filter examples were designed for wireless local area network (WLAN) of 2.4/5.2 GHz. The measured insertion losses, return losses and fractional bandwidths (FBW) are 1.43 dB, 10 dB, and 14.8% at 2.4 GHz and 1.34 dB, 10 dB, and 12.9% at 5.2 GHz. Moreover, by applying two quarter-wavelength stubs on the input/output ports, the passband selectivity with an isolation of 40 dB can be achieved. The simulation and measurement have a close match, verifying the design concept. Full article

(This article belongs to the Special Issue Microwave Devices Design and Application)

► Show Figures

Figure 1

8 pages, 1756 KiB

Open AccessArticle

A Bandpass Filter Using Half Mode SIW Structure with Step Impedance Resonator

by Min-Hang Weng, Chin-Yi Tsai, De-Li Chen, Yi-Chun Chung and Ru-Yuan Yang

Electronics 2021, 10(1), 51; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics10010051 - 30 Dec 2020

Cited by 12 | Viewed by 2185

Abstract

This paper presents a miniaturized bandpass filter, which uses half mode substrate integrated waveguide (HMSIW) structure with embedded step impedance structure (SIS). By embedding the stepped impedance structure into the top metal of the waveguide cavity, the center frequency can be quickly shifted to a lower frequency. The operating center frequency of the proposed bandpass filter (BPF) using HMSIW resonators with embedded SIS is tunable as functions of the parameters of the SIS. The design curve is provided. A filter example of the center frequency of the filter at 3.5 GHz is fabricated and measured, having the insertion loss |S₂₁| less than 3 dB, and the return loss |S₁₁| greater than 10 dB. The transmission zeros are located at 2.95 GHz and 3.95 GHz on both sides of the passband, both of which are lower than 30 dB. The simulation result and the measured response conform to the proposed design concept. The proposed HMSIW filter design is in line with the current 5G communication trend. Full article

(This article belongs to the Special Issue Microwave Devices Design and Application)

► Show Figures

Figure 1

14 pages, 7486 KiB

Open AccessArticle

Single-Layer Line-Fed Broadband Microstrip Patch Antenna on Thin Substrates

by Roberto Vincenti Gatti, Riccardo Rossi and Marco Dionigi

Electronics 2021, 10(1), 37; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics10010037 - 29 Dec 2020

Cited by 10 | Viewed by 10438

Abstract

In this work, the issue of limited bandwidth typical of microstrip antennas realized on a single thin substrate is addressed. A simple yet effective design approach is proposed based on the combination of traditional single-resonance patch geometries. Two novel shaped microstrip patch antenna elements with an inset feed are presented. Despite being printed on a single-layer substrate with reduced thickness, both radiators are characterized by a broadband behavior. The antennas are prototyped with a low-cost and fast manufacturing process, and measured results validate the simulations. State-of-the-art performance is obtained when compared to the existing literature, with measured fractional bandwidths of 3.71% and 6.12% around 10 GHz on a 0.508-mm-thick Teflon-based substrate. The small feeding line width could be an appealing feature whenever such radiating elements are to be used in array configurations. Full article

(This article belongs to the Special Issue Microwave Devices Design and Application)

► Show Figures

Figure 1

11 pages, 4865 KiB

Open AccessFeature PaperArticle

Effect of A Superstrate on On-Head Matched Antennas for Biomedical Applications

by Md Rokunuzzaman Robel, Asif Ahmed, Akram Alomainy and Wayne S. T. Rowe

Electronics 2020, 9(7), 1099; https://0-doi-org.brum.beds.ac.uk/10.3390/electronics9071099 - 06 Jul 2020

Cited by 1 | Viewed by 2344

Abstract

The effect of using a superstrate dielectric layer on an on-head matched antenna for biomedical diagnosis applications is investigated. Two on-head matched antennas are considered with different length meandered lines ensuring operation around 0.9 GHz frequency. The first antenna’s conductive radiating structure is in direct contact with the head phantom, whereas the second one utilises a 0.5 mm thick superstrate layer on top of the conducting layer as a buffer. The lateral dimensions of both antennas are held constant at 30 × 30 mm². The electric and magnetic field distribution is analysed and the power penetration, 50 mm inside the head phantom, is derived from the electromagnetic field surrounding the antennas. Both homogeneous and inhomogeneous head phantoms are considered while evaluating the antennas in terms of their reflection coefficient, current distribution, electric field, magnetic field, specific absorption rate (SAR) and power penetration inside the head. The antennas are fabricated and measured utilizing an inhomogeneous phantom to validate the proposed performance improvement using a superstrate. It is shown that the superstrate antenna achieves a ~8 dB increase in power penetration inside the head phantom along with a 0.0731 W/kg decrease in SAR compared to the antenna without a superstrate. Full article

(This article belongs to the Special Issue Microwave Devices Design and Application)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Microwave Devices Design and Application

Share This Special Issue

Special Issue Editor

Special Issue Information

Published Papers (12 papers)

Research

Further Information

Guidelines

MDPI Initiatives

Follow MDPI