Electrical characteristics of gated‐anode diodes based on normally‐off GaN HEMT structures for rectenna applications

Electronics Letters

Published On 2021/10

Here, a gated‐anode diode (GAD) is proposed where an anode electrode is formed by connecting a gate electrode and an ohmic electrode of a normally‐off GaN HEMT for a 5.8 GHz rectenna. A wide recessed gate GaN GADs were prepared and the recess length dependence of their electrical characteristics was investigated. Typical DC characteristics of the HEMTs are a threshold voltage (Vth) of +0.3 V and a maximum drain current (Imax) of 300 mA/mm. The GADs showed the characteristics of maximum forward current (If) of 350 mA/mm, reverse breakdown voltage (BVr) of 40 V, and off‐state capacitance (Coff) of 0.28 pF/mm by using optimized recess length. We constructed SPICE model of the GADs. The SPICE simulation predicted a rectifier efficiency of 81% and a DC output power of 10 W for bridge type 5.8 GHz rectifier using four GADs with each gate width of 0.8 mm.

Journal

Electronics Letters

Published On

2021/10

Volume

57

Issue

21

Page

810-812

Authors

Suda Jun

Suda Jun

Nagoya University

Position

/ Kyoto University

H-Index(all)

47

H-Index(since 2020)

32

I-10 Index(all)

0

I-10 Index(since 2020)

0

Citation(all)

0

Citation(since 2020)

0

Cited By

0

Research Interests

Physics

Electronics

Semiconductors

University Profile Page

Yuji Ando

Yuji Ando

Nagoya University

Position

H-Index(all)

29

H-Index(since 2020)

13

I-10 Index(all)

0

I-10 Index(since 2020)

0

Citation(all)

0

Citation(since 2020)

0

Cited By

0

Research Interests

Semiconductor devices

University Profile Page

Naoki Sakai

Naoki Sakai

Kanazawa Institute of Technology

Position

H-Index(all)

8

H-Index(since 2020)

6

I-10 Index(all)

0

I-10 Index(since 2020)

0

Citation(all)

0

Citation(since 2020)

0

Cited By

0

Research Interests

Microwave circuit

Wireless power transfer

Rectifier

University Profile Page

Other Articles from authors

Suda Jun

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Suda Jun

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Nagoya University

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Electrical characterization of AlGaN/GaN-HEMTs on semi-insulating GaN substrates doped with Fe, C, or Mn and grown by hydride vapor phase epitaxy

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Suda Jun

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Suda Jun

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Yuji Ando

Yuji Ando

Nagoya University

Laser slicing of GaN

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Nagoya University

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Suda Jun

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Other articles from Electronics Letters journal

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DHGL: Dynamic hypergraph‐based deep learning model for disease prediction

Electronic health record (EHR) data is crucial in providing comprehensive historical disease information for patients and is frequently utilized in health event prediction. However, current deep learning models that rely on EHR data encounter significant challenges. These include inadequate exploration of higher‐order relationships among diseases, a failure to capture dynamic relationships in existing relationship‐based disease prediction models, and insufficient utilization of patient symptom information. To address these limitations, a novel dynamic HyperGraph‐based deep learning model is introduced for disease prediction (DHGL) in this study. Initially, pertinent symptom information is extracted from patients to assign them with an initial embedding. Subsequently, sub‐hypergraphs are constructed to consider distinct patient cohorts rather than treating them as isolated entities. Ultimately, these hypergraphs are …

Periklis Petropoulos

Periklis Petropoulos

University of Southampton

Electronics Letters

Mechanical dicing of optical quality facets and waveguides in a silicon nitride platform

The authors report a ductile dicing process for manufacturing optical‐quality facets in a multi‐layered silicon nitride platform without the need for polishing. A surface roughness (Sa) of 1.5 nm was achieved. This technique was extended to fabricate ridge waveguides, and the results and characterization are reported.

Linda DeBrunner

Linda DeBrunner

Florida State University

Electronics Letters

An efficient implementation for linear convolution with reduced latency in FPGA

A recently developed linear convolution filter based on Hirschman theory has shown its advantage in saving computations compared with other convolution filters. Here, the Hirschman convolution filter is improved with the use of the split‐radix algorithm and explore its latency‐reduced advantage for the first time. A comparison of hardware resources in Field Programmable Gate Array (FPGA) between the proposed Hirschman‐based filter and other convolution filters is presented. Simulation results indicate that the split‐radix Hirschman convolution filter achieves a promising reduction in latency by 18.15% on average with an acceptable power consumption rise by about 3.05%. In the case of a device capacity limited implementation, the proposed Hirschman convolution filter is still computationally attractive as it uses a small‐size originator function instead of larger Fourier transform.

Thalia Domínguez Bucio

Thalia Domínguez Bucio

University of Southampton

Electronics Letters

Mechanical dicing of optical quality facets and waveguides in a silicon nitride platform

The authors report a ductile dicing process for manufacturing optical‐quality facets in a multi‐layered silicon nitride platform without the need for polishing. A surface roughness (Sa) of 1.5 nm was achieved. This technique was extended to fabricate ridge waveguides, and the results and characterization are reported.

Yongwei Huang

Yongwei Huang

Guangdong University of Technology

Electronics Letters

Robust receive beamforming and reflection coefficients optimization in an IRS‐aided decode‐and‐forward relay system

Consider a decode‐and‐forward wireless relay system assisted by an intelligent reflection surface (IRS), where a robust design on receive beamforming at the relay and reflection coefficients at the IRS is studied. The worst‐case signal‐to‐noise ratio maximization problem is formulated, subject to the reflection coefficients (with either continuous or discrete phases) constraints, under the assumption of imperfect channel state information for all channels. To cope with the hard problem, an equivalent nonconvex quadratic optimization problem with a simpler form is derived, and then the Cauchy‐Schwarz inequality is applied to update the beamforming and a cyclic process is proposed to update the reflection coefficients, where a closed‐form optimal solution is computed in each step. It turns out that the proposed algorithm achieves a locally optimal solution for the robust design problem. Simulation results show that …

Akanksha Bhutani

Akanksha Bhutani

Karlsruher Institut für Technologie

Electronics Letters

A 53–125 GHz chip to double‐ridge rectangular waveguide transition

A novel chip to double‐ridge rectangular waveguide transition, with an ultra‐broadband operation bandwidth exceeding three standard rectangular waveguide (WR) bands of WR15, WR12, and WR10 is demonstrated for the first time in this letter, to the best of authors' knowledge. This bandwidth is achieved by coupling the microstrip mode directly to the fundamental TE mode of the waveguide. A unique feature of this transition is that the transition design can be implemented on substrates with a high dielectric constant, which makes it suitable for integration with monolithic microwave integrated circuits (MMICs). A back‐to‐back transition is realized using a split‐block assembly and 254 μm$\umu {\rm {m}}$ thickness alumina substrate (εr=9.8$\varepsilon _{\text{r}}=9.8$ at 80 GHz). The latter acts as an MMIC substrate substitute, including a tapered microstrip and a 50 Ω$\Omega$ coplanar waveguide pad for probe …

Rafał Kopacz

Rafał Kopacz

Politechnika Warszawska

Electronics Letters

New single‐stage bidirectional three‐phase ac‐dc solid‐state transformer

High‐power applications with low‐voltage (LV) dc loads, for example, fast charging stations for electric vehicles (EVs), are typically supplied from the medium‐voltage (MV) grid. Aiming for low volume, MVac‐LVdc solid‐state transformers (SSTs) that provide galvanic separation with medium‐frequency transformers (MFTs) are thus considered, which are conventionally realized as two‐stage systems that consist of an ac‐dc power‐factor‐correction (PFC) rectifier and an isolated dc‐dc converter. This letter extends a new single‐stage isolated bidirectional PFC rectifier concept to MV levels, resulting in an SST that performs MVac‐LVdc conversion in a single converter stage and, unlike many modular SST concepts, employs only a single MFT. The SST's primary side operates modular‐multilevel‐converter (MMC) bridge legs, whose input voltages contain large ac components, in the quasi‐two‐level mode to minimize …