2024/09/18 更新

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写真a

バラカツト アデイル タワフイツク モハマツド モハマツド
BARAKAT ADEL TAWFIK MOHAMED MOHAMED
BARAKAT TAWFIK MOHAMED MOHAMED ADEL
所属
システム情報科学研究院 I&Eビジョナリー特別部門 助教
工学部 電気情報工学科(併任)
システム情報科学府 電気電子工学専攻(併任)
職名
助教
連絡先
メールアドレス
電話番号
0928023707

学位

  • 学士(工学)、マンスーラ大学、エジプト

  • 修士 (工学)、エジプト日本科学技術大学、エジプト

  • 博士 (工学)、エジプト日本科学技術大学、エジプト

研究テーマ・研究キーワード

  • 研究テーマ:次世代の生物医学インプラントのためのワイヤレス電力伝送

    研究キーワード:ワイヤレス電力伝送 (WPT), バンドパスフィルター (BPF), 亡命グラウンド構造 (DGS)

    研究期間: 2016年4月

  • 研究テーマ:フィルター・チップ上のミリ波帯で

    研究キーワード:バンドパスフィルター(BPF), 亡命接地構造(DGS)

    研究期間: 2015年2月 - 2017年2月

  • 研究テーマ:60 GHz オンチップ統合型アンテナ

    研究キーワード:アンテナ、60 GHz帯、オン・チップ

    研究期間: 2010年2月 - 2015年2月

受賞

  • EuMW 2014 Student Grant

    2014年10月   European Microwave Association  

  • Nine month special research student at EJUST center, Kyushu University

    2013年7月   Egyptian Ministry of Higher Education  

  • PHD initiative sponsorship

    2013年6月   IEEE MTT society  

  • Best student paper award

    2012年3月   2012 Japan-Egypt Conference on electronics, communications and computers  

  • Japan Study Program (JSP)

    2012年3月   Government of Japan  

  • Short-Term travel to Japan

    2011年6月   Center for Japan-Egypt Cooperation in Science and Technology (EJUST Center) at Kyushu University  

  • 1st paper by EJUST student

    2010年8月   Egypt-Japan University of Science and Technology  

  • Five years scholarship to obtain MSc. and Ph.D. degrees

    2010年2月   Egyptain Ministry of Higher Education  

▼全件表示

論文

  • Design Approach for Efficient Wireless Power Transfer Systems During Lateral Misalignment 査読 国際誌

    Barakat, Adel; Yoshitomi, Kuniaki; Pokharel, Ramesh K.

    IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES   66 ( 9 )   4170 - 4177   2018年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1109/TMTT.2018.2852661

  • Ultracompact CMOS 60-GHz Tapped-Line Combline BPF With Two Transmission Zeros Using Defected Ground Structures 査読 国際誌

    Elsaidy, Elsayed; Barakat, Adel; Abdel-Rahman, Adel B.; Allam, Ahmed; Pokharel, Ramesh K.

    IEEE TRANSACTIONS ON COMPONENTS PACKAGING AND MANUFACTURING TECHNOLOGY   8 ( 9 )   1642 - 1649   2018年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1109/TCPMT.2018.2861411

  • 22-GHz-Band Oscillator Using Integrated H-Shape Defected Ground Structure Resonator in 0.18-mu m CMOS Technology 招待 査読 国際誌

    Nusrat Jahan, Siti Amalina Enche Ab Rahim, Hamed Mosalam, Adel Barakat, Takana Kaho, Ramesh K. Pokharel,

    IEEE MICROWAVE AND WIRELESS COMPONENTS LETTERS   28 ( 3 )   233 - 235   2018年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1109/LMWC.2018.2801031

  • Dual-Band Defected Ground Structures Wireless Power Transfer System With Independent External and Inter-Resonator Coupling 招待 査読 国際誌

    Fairus Tahar, Adel Barakat, Redzuan Saad, Kuniaki Yoshitomi, Ramesh K. Pokharel

    IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS II-EXPRESS BRIEFS   64 ( 12 )   1372 - 1376   2017年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1109/TCSII.2017.2740401

  • 1.06 FoM and Compact Wireless Power Transfer System Using Rectangular Defected Ground Structure Resonators 査読 国際誌

    Fairus Tahar, Redzuan Saad, Adel Barakat, Ramesh Kumar Pokharel

    IEEE Microwave and Wireless Components Letters   27 ( 11 )   1025 - 1025   2017年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1109/LMWC.2017.2750032

    その他リンク: http://ieeexplore.ieee.org/document/8059822/

  • Ultracompact 60-GHz CMOS BPF Employing Broadside-Coupled Open-Loop Resonators 査読 国際誌

    Anwer S. Abd El-Hameed, Adel Barakat, Adel B. Abdel-Rahman, Ahmed Allam, Ramesh Kumar Pokharel

    IEEE Microwave and Wireless Components Letters   27 ( 9 )   818 - 820   2017年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    その他リンク: http://ieeexplore.ieee.org/document/8010799/

  • Design and Application of Virtual Inductance of Square-Shaped Defected Ground Structure in 0.18- μm CMOS Technology 査読 国際誌

    5 ( 5 )   2168 - 6734   2017年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    This paper investigates a possibility of application of a virtual inductor realized by an integrated defected ground structure (DGS) to design a front-end circuit in CMOS technology. Two types of DGS are analyzed and found that the inductance realized by a square-shaped DGS achieves smaller size and higher quality factor than an H-shaped DGS. Then, a 15-GHz low phase noise voltage-controlled oscillator (VCO) employing the proposed square-shaped DGS in 0.18-μm 1P6M CMOS technology is designed. The fabricated VCO operates from 15.2 to 16.12 GHz and consumes 5-mW power. The measured phase noise is -132.08 dBc/Hz at 10-MHz offset frequency, and this results in the figure of merit (FoM) and FoM taking account of the area to be 189.1 and 199.9 dB, respectively.

    DOI: 10.1109/JEDS.2017.2728686

    その他リンク: http://ieeexplore.ieee.org/document/7984797/

  • 60 GHz CMOS Circular Patch Antenna on Chip 査読 国際誌

    Adel Barakat, Ahmed Allam, Hala Elsadek, Adel B. Abdel-Rahman, Ramesh Kumar Pokharel, Americ Bisognin, Cyril Luxey

    Microwave Journal   60 ( 2 )   90 - 100   2017年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  • A Novel Technique for Compact Size Wireless Power Transfer Applications Using Defected Ground Structures 査読 国際誌

    Sherif Hekal, Adel B. Abdel-Rahman, Hongting Jia, Ahmed Allam, Adel Barakat, Ramesh Kumar Pokharel

    IEEE Transactions on Microwave Theory and Techniques   65 ( 1 )   591 - 599   2017年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: http://dx.doi.org/10.1109/TMTT.2016.2618919

    その他リンク: http://dx.doi.org/10.1109/TMTT.2016.2618919

  • Asymmetric Wireless Power Transfer Systems Using Coupled DGS Resonators 査読 国際誌

    Sherif Hekal, Adel B. Abdel-Rahman, Ahemd Allam, Hongting Jia, Adel Barakat, Ramesh Kumar Pokharel

    IEICE Electronics Express   13 ( 21 )   20160591   2016年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: http://doi.org/10.1587/elex.13.20160591

    その他リンク: http://doi.org/10.1587/elex.13.20160591

  • Compact Wireless Power Transfer System Using Defected Ground Bandstop Filters 査読 国際誌

    Sherif Hekal, Adel B. Abdel-Rahman, Hongting Jia, Ahmed Allam, Adel Barakat, Takano Kaho, Ramesh Kumar Pokharel

    IEEE Microwave and Wireless Components Letters   26 ( 10 )   2016年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1109/LMWC.2016.2601300

    その他リンク: http://dx.doi.org/10.1109/LMWC.2016.2601300

  • Compact Size On-Chip 60 GHz H-Shaped Resonator BPF 査読 国際誌

    Nessim Mahmoud, Adel Barakat, Adel B. Abdel-Rahman, Ahmed Allam, Ramesh Kumar Pokharel

    IEEE Microwave and Wireless Components Letters   26 ( 9 )   681 - 683   2016年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1109/LMWC.2016.2597219

    その他リンク: http://ieeexplore.ieee.org/document/7542143/?arnumber=7542143

  • Miniaturized Low loss 60GHz CMOS Mixed Coupled BPF with Patterned Ground shield 査読 国際誌

    Adel Barakat, Muhammad Hanif, Ramesh Kumar Pokharel

    Microwave and Optical Technology letters   58 ( 3 )   697 - 699   2016年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1002/mop.29650

    その他リンク: http://onlinelibrary.wiley.com/doi/10.1002/mop.29650/full

  • Improved gain 60 GHz CMOS antenna with N-well grid 査読 国際誌

    Adel Barakat, Ahmed Allam, Hala Elsadek, Adel Abdelrahman, Ramesh Kumar Pokharel, Takana Kaho

    IEICE Electronics Express   13 ( 5 )   2016年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1587/elex.13.20151115

    その他リンク: https://www.jstage.jst.go.jp/article/elex/advpub/0/advpub_13.20151115/_article

  • 60 GHz on-chip mixed coupled BPF with H-shaped defected ground structures 査読 国際誌

    Adel Barakat, Ramesh Kumar Pokharel, Takana Kaho

    Electronics Letters   2016年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1049/el.2015.4465

    その他リンク: http://digital-library.theiet.org/content/journals/10.1049/el.2015.4465

  • An Efficient Inverse Modeling Method Using Translator-Inspired Neural Network and Dual-Annealing for a Compact WPT System 査読

    Jiang X., Pokharel R.K., Barakat A.

    IEEE Transactions on Antennas and Propagation   72 ( 4 )   3282 - 3291   2024年4月   ISSN:0018926X

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IEEE Transactions on Antennas and Propagation  

    This article proposes a novel prediction method for efficient inverse modeling of a compact wireless power transfer (WPT) system. Impedance matching circuit analysis with admittance (J-) inverter theory is used for coupling analysis. Then, a simple translator-inspired neural network is proposed to predict scattering (S-) parameters from 100 MHz to 1 GHz for each coupling case. The training dataset comprises 2900 randomly generated dimensions and the corresponding S-parameters via full-wave simulation. Consequently, the power transfer efficiency (PTE) can be figured out using the S-parameter, which varies from different coupled modes. Then, a dual-annealing algorithm is leveraged to find the best dimensions. The predicted dimensions, including the transmitter (Tx) and receiver (Rx) layouts, values of the etched capacitors, and WPT distances, meet the design purposes. Compared to the state-of-the-art approaches, the proposed method can efficiently optimize the WPT system with desired frequencies. The proposed inverse model reveals new insights and understanding of the prediction and optimization of inductively coupled WPT.

    DOI: 10.1109/TAP.2024.3372149

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  • Design of Miniaturized Sub-6 GHz Rectifier with Self-Impedance Matching Technique

    Gyawali B., Aboualalaa M., Barakat A., Pokharel R.K.

    IEEE Transactions on Circuits and Systems I: Regular Papers   71 ( 7 )   3413 - 3422   2024年   ISSN:15498328

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    掲載種別:研究論文(学術雑誌)   出版者・発行元:IEEE Transactions on Circuits and Systems I: Regular Papers  

    This work presents a novel concept of self-impedance matching in rectifier design by integrating a driving rectifier in parallel with a conventional voltage doubler circuit. The input impedance of the wideband rectifier is perfectly matched with the use of driving rectifier, which consists of a half-wave rectifier, a series stub line, and a grounding capacitor. The series stub adjusts the operating frequency and the efficiency bandwidth (EBW) of the proposed rectifier. This approach streamlines the rectifier design by eliminating additional input impedance matching networks and offers simultaneous control of EBW and operating bandwidth. Instead of a conventional lossy microstrip line, a Defected Ground Structure (DGS) is employed to design a high-impedance series stub line which makes the proposed circuit compact with improved quality factor. The experimental results highlight the effectiveness of the proposed rectifier, achieving more than 50% power conversion efficiency (PCE) for the frequency range of 3 GHz to 5.8 GHz, covering entire sub-6 GHz band of the 5G network with minimal variation. The fabricated prototype is the most compact design, with a circuit size of only 0.756 cm2.

    DOI: 10.1109/TCSI.2024.3397810

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  • Efficient and Low Leakage WPT System with Integrated Uncomplicated Matching Circuit Rectifier Using Metamaterial Director and Isolator for Biomedical Application

    Alshhawy S., Barakat A., Pokharel R.K.

    IEEE Journal of Electromagnetics, RF and Microwaves in Medicine and Biology   8 ( 2 )   144 - 154   2024年

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    掲載種別:研究論文(学術雑誌)   出版者・発行元:IEEE Journal of Electromagnetics, RF and Microwaves in Medicine and Biology  

    Supplying wireless power to biomedical implants presents numerous challenges, including the compactness, efficiency, and biomedical safety of the receiver (RX). In this work, we propose several solutions to overcome these challenges. Firstly, we designed a metamaterial-inspired transmitter (TX) based on a multi-ring resonator (MRR). This transmitter achieves low magnetic loss and is used as a director to supply power to the RX, featuring an integrated uncomplicated matching circuit rectifier. Secondly, to realize the rectifier, we leverage the high coupling achieved through the proposed MRR metamaterial. The rectifier is integrated on the backside of the RX substrate without requiring additional area for further compactness. Additionally, we introduce a metamaterial-based isolator designed to reduce magnetic field leakage on the back side of the system. Importantly, this isolator has been proven to have no adverse effects on the original wireless power transfer (WPT) system's performance. A prototype was successfully fabricated, and both RF-dc simulation and measurements indicate a peak efficiency of 43% and 39%, respectively, at 50 MHz for a 9 mm embedded RX in chicken breast tissue. The TX size is 20 mm × 20 mm, while the integrated RX/rectifier has dimensions of 7 mm × 7 mm.

    DOI: 10.1109/JERM.2024.3395572

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  • Experimental Study on Transition Loss of On-Chip SIW Interconnects and Transmission Lines Using Two De-Embedding Reference Planes in 200 GHz Band Frequency

    Thapa S.K., Pokharel R.K., Barakat A., Amakawa S., Mubarak M.H., Hara S., Watanabe I., Kasamatsu A.

    IEEE MTT-S International Microwave Symposium Digest   694 - 697   2024年   ISSN:0149645X ISBN:9798350375046

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    出版者・発行元:IEEE MTT-S International Microwave Symposium Digest  

    A method for calculating transition loss in long lowloss substrate integrated waveguide (SIW)-based transmission lines fabricated using commercial complementary metal-oxidesemiconductor (CMOS) technology is presented. To quantify the accurate transition loss, the proposed approach employed twostep de-embedding technique besides normal measurement setup calibration using impedance standard substrate (ISS) at two distinct reference points: the first mitigates measuring pad effects, and the second removes both pads and transition structures. By using the attenuation constants calculated from these reference planes, the intrinsic transition loss is estimated. From the experiment, a low transition loss is observed in the proposed SIW design, which varies between 0.2 dB and 1.3 dB over a wide measurement bandwidth of 120 to 220 GHz. The experimental results underscore the efficacy of the proposed method and suggest the potential for consistent performance above the current measurement threshold of 220 GHz, which could be pivotal for terahertz (THz) applications.

    DOI: 10.1109/IMS40175.2024.10600291

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  • Improvement of Data Rate of SWIPT System in Phantom by Integrated Metamaterial-Inspired Absorber for Biomedical Applications

    Jiang X., Pokharel R.K., Barakat A.

    IEEE MTT-S International Microwave Symposium Digest   10 - 13   2024年   ISSN:0149645X ISBN:9798350375046

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    出版者・発行元:IEEE MTT-S International Microwave Symposium Digest  

    This paper proposes a metamaterial-inspired absorber designed to enhance isolation in a simultaneous wireless information and power transfer (SWIPT) system through biological tissue. The study delves into the metamaterial perspective, focusing on the characteristics of split-ring resonators (SRRs) within the proposed absorber unit cells. The absorber exhibits a significant real part near -1 and an imaginary part close to 0 in permeability. A 10-mm-thick human body equivalent phantom is used for the SWIPT system's evaluation. Experimental results indicate that embedding this absorber between power and signal ports in both Tx and Rx of a SWIPT system results in a 3 dB improvement in isolation performance. Concurrently, with the assistance of the proposed absorber, the datarate improves by 3.6 Mb/s, allowing signals to be transmitted with 5 dBm weaker power than the original system.

    DOI: 10.1109/IMS40175.2024.10600186

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  • New Rectification Technique Employing Auxiliary Rectifier for Resonance Control Achieving Compact Size and High Efficiency in CMOS

    Gyawali B., Pokharel R.K., Thapa S.K., Barakat A., Shinohara N.

    IEEE Solid-State Circuits Letters   7   187 - 190   2024年   eISSN:2573-9603

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    掲載種別:研究論文(学術雑誌)   出版者・発行元:IEEE Solid-State Circuits Letters  

    This article presents the design and realization of a compact size high-efficiency complementary metal-oxide- semiconductor rectifier with resonance control technique employing the concept of parallel rectifier. The methodology involves the integration of two rectifiers, where one is main rectifier, specifically designated for rectification purposes and the other is auxiliary, serves for impedance matching, resulting in no matching at input. Furthermore, the auxiliary rectifier offers control over resonance of the proposed rectifier. The proposed design achieves more than 40% conversion efficiency at 22 dBm of input power for the broadband range from 2.4 to 3.5 GHz, with an active circuit size of 0.21 mm2.

    DOI: 10.1109/lssc.2024.3409710

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  • Two gm/ID design approaches for high-performance dual-resistive feedback noise-cancelling LNA

    Almonaier A.M.K., Barakat A., Areed N.F.F.

    International Journal of Electronics   2024年   ISSN:00207217

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    出版者・発行元:International Journal of Electronics  

    In this article, a self-bias MOSFET-based dual-resistive feedback low-noise amplifier (LNA) is investigated. A detailed mathematical analysis of the addressed amplifier has been carried out using the return ratio-based feedback analysis technique. Furthermore, the LNAs have been simulated via Cadence using the TSMC 65 nm PDK. Two (Formula presented.) strategies are described to handle the performance trade-offs for enhancing gain, noise figure (NF) and power consumption. The two strategies are conceptually similar to one another, with the selection of the transconductance efficiency being the only difference. While the first technique uses a transconductance efficiency to achieve the lowest power consumption while keeping an acceptable NF, the second strategy uses a particular transconductance efficiency for flawless noise cancelling without consideration for reduced power consumption. According to simulation results, the first recommended LNA has a voltage gain of 12 dB over a 3 dB bandwidth of 0.5–10 GHz, a minimal NF of 1.7 dB @ 7.014 GHz, a maximum NF of 1.932 dB @ 0.5 GHz, consumes 12.42 mW from a low supply voltage of 1.2 V and achieved a third-order intercept of −2.34 dBm @ 1 GHz. The simulation results of the second recommended LNA also show that it can operate with a low supply voltage of 1.2 V and still achieve a minimum NF of 0.978 dB @ 2.729 GHz, a maximum NF of 1.048 dB @ 6 GHz, (Formula presented.) of 1.34 dBm and a voltage gain of 13 dB over a 3 dB bandwidth of 0.5–6 GHz with a consuming power of 25 mW.

    DOI: 10.1080/00207217.2024.2384001

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  • Low-Pass Filtering Admittance Inverter for High Out-of-Band Rejection Millimeter-Wave On-Chip BPF 査読

    Barakat A., Pokharel R.K.

    IEEE Transactions on Circuits and Systems II: Express Briefs   70 ( 11 )   3963 - 3967   2023年11月   ISSN:15497747

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IEEE Transactions on Circuits and Systems II: Express Briefs  

    This brief proposes an on-chip bandpass filter (BPF) that achieves low loss and reduced out-of-band rejection by cascading two resonators and a low pass filtering admittance (J) inverter between them. The proposed J-inverter uses a T-network with negative mutual coupling to generate a transmission zero, and the design equations for this component are provided and verified through circuit simulations. Additionally, a resonator is proposed that utilizes a high impedance line loaded capacitor, and its poles and zeros are thoroughly investigated. Finally, the efficacy of the proposed approach is demonstrated through an on-chip prototype. The measured results show an insertion loss of 3.3 dB at 61 GHz, a 3-dB fractional bandwidth of 25%, and an extended rejection of less than 30 dB between 82 GHz and 115 GHz.

    DOI: 10.1109/TCSII.2023.3283532

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  • Implementation of SIW Cavity in Commercial CMOS Technology for Sub-Terahertz Band Applications 査読

    Thapa S.K., Pokharel R.K., Barakat A., Dong R., Amakawa S., Hara S., Watanabe I., Kasamatsu A.

    IEEE MTT-S International Microwave Symposium Digest   2023-June   493 - 496   2023年6月   ISSN:0149-645X ISBN:9798350347647

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    記述言語:英語   掲載種別:研究論文(その他学術会議資料等)   出版者・発行元:IEEE MTT-S International Microwave Symposium Digest  

    For sub-terahertz band applications, two compact and low-loss on-chip substrate integrated waveguide (SIW) cavities are designed in CMOS technology. Compact size cavity is achieved by utilizing the folded ridge structure in the quarter mode SIW (QMSIW) structure which is loaded with complementary split-ring resonators (CSRRs). Two prototypes of the proposed QMSIW cavities with and without CSRR are fabricated in 1P6M CMOS technology. From the measurement, both cavities present return losses higher than 27 dB and external Q-factors higher than 140. The proposed work shows that even at such high frequencies, compact and low-loss SIWs can be fabricated in commercial CMOS technology and opens a window to utilizing such cavities for other low-loss components such as oscillators, on-chip bandpass filters and on-chip antennas for sub-terahertz band applications.

    DOI: 10.1109/IMS37964.2023.10188161

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  • Hybrid SRR-Based Stacked Metamaterial for Miniaturized Dual-Band Wireless Power Transfer System 査読

    Jiang X., Pokharel R.K., Barakat A., Yoshitomi K.

    IEEE Transactions on Antennas and Propagation   71 ( 6 )   5014 - 5025   2023年6月   ISSN:0018926X

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IEEE Transactions on Antennas and Propagation  

    A novel stacked wideband metamaterial is proposed for a robust and compact dual-band wireless power transfer (WPT) system. The proposed metamaterial employs split-ring resonator (SRR) unit cells loaded by nonuniform capacitors. First, two types of unit cells that exhibit two resonance frequencies are analyzed. The results show that it can only improve the coupling between the transmitter (Tx) and the receiver (Rx) at the single band. Then, each unit cell is sandwiched with each other, and a hybrid unit cell that indicates three resonance frequencies is finally proposed. The hybrid SRR exhibits near-zero permeability within the wide frequency range of interest. Therefore, the proposed metamaterial is effective at both bands simultaneously. The system was fabricated and tested, including a compact dual-band WPT system. The size of the Tx (Rx) and the metamaterial is $15\times15$ and $20\times20$ mm, respectively. The measured figures of merit (FOM) are 0.92 at 390 MHz and 0.85 at 770 MHz at a power transfer distance of 20 mm, which is a significant improvement over recently proposed dual-band WPT systems with metamaterials.

    DOI: 10.1109/TAP.2023.3262977

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  • 200 GHz-band Low-loss Half-Mode SIW CMOS Interconnects and Transmission Lines for Sub-Terahertz Frequency Band Applications 査読

    Pokharel R.K., Fukuda T., Thapa S.K., Barakat A., Dong R., Hara S., Watanabe I., Kasamatsu A.

    IEEE MTT-S International Microwave Symposium Digest   2023-June   497 - 500   2023年6月   ISSN:0149-645X ISBN:9798350347647

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    記述言語:英語   掲載種別:研究論文(その他学術会議資料等)   出版者・発行元:IEEE MTT-S International Microwave Symposium Digest  

    Low-loss half-mode substrate integrated waveguide (HMSIW)-based interconnects and transmission lines are designed and implemented in Complementary Metal-Oxide Semiconductor (CMOS) technology. In HMSIW interconnects, complementary split ring resonators (CSRR) whose self-resonance is much higher than the cut-off frequency of the SIW are etched on, due to which matching is improved. By controlling the parameters of the CSRRs, the losses due to microstrip to SIW transition are substantially improved, and no extra external matching circuit is required. A prototype was fabricated in 1P6M CMOS technology and tested. The measured cut-off frequency of the proposed HMSIW transmission line is 110 GHz, and the measured attenuation constant at frequencies of 175-220 GHz is less than 1.4 dB/mm. This work confirms a significant performance improvement of the CMOS interconnects in the sub-terahertz frequency band.

    DOI: 10.1109/IMS37964.2023.10188034

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  • Comparator-less ASK-PWM CDR Circuit for Forward Data Communication Over A Single Channel Wireless Power and Data Transfer System 査読

    Barakat A., Bin Zulkalnain M.K., Pokharel R.

    2023 IEEE Wireless Power Technology Conference and Expo, WPTCE 2023 - Proceedings   2023年6月   ISBN:9798350337372

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    記述言語:英語   掲載種別:研究論文(その他学術会議資料等)   出版者・発行元:2023 IEEE Wireless Power Technology Conference and Expo, WPTCE 2023 - Proceedings  

    In this work, a new clock and data recovery (CDR) scheme is proposed for amplitude shift keying (ASK) with pulse width modulation (PWM) encoding. Such a technique can fully recover the clock as well as the encoded data without the need for any comparator. The clock is recovered by passing the ASK-PWM encoded data to the frequency divider and frequency multiplier. Then, the data sampler can recover the data by sampling the ASK-PWM modulated data using a delayed version of the recovered clock with no additional processing. This technique is intended for a data transfer system over an inductively coupled wireless power transfer system (WPT) system for biomedical implants where the data will modulate the power carrier without the need for a dedicated data channel. A prototype example implementation of the CDR scheme on a 180 nm Complementary-Metal-Oxide-Semiconductor (CMOS) technology with a data rate of 2 Mbps is provided as a proof-of-concept. This CDR prototype has an area of 8000 μm2 and consumes a power of 129 microwatts from a 1.4 Voltage dc supply.

    DOI: 10.1109/WPTCE56855.2023.10215978

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  • Frequency Switching Dual Power Band Rectifier with Load-Modulation Technique 査読

    Gyawali B., Thapa S.K., Aboualalaa M., Barakat A., Pokharel R.K.

    2023 IEEE Wireless Power Technology Conference and Expo, WPTCE 2023 - Proceedings   2023年6月   ISBN:9798350337372

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    記述言語:英語   掲載種別:研究論文(その他学術会議資料等)   出版者・発行元:2023 IEEE Wireless Power Technology Conference and Expo, WPTCE 2023 - Proceedings  

    The frequency switching dual power band rectifier is proposed to achieve both low-power and high-power applications from a single circuit. Two different operating frequencies f1 = 900 MHz and f2 = 2.4 GHz are selected for low-power and high-power applications, respectively. The proposed rectifier fulfills stable operation at two levels of input power by making frequency switching. The Schottky diodes HSMS 2850 and HSMS 2860 are selected for f1 and f2, respectively, based on their performance with respect to the input power. Instead of conventional lumped inductors, defected ground structure (DGS)-based inductors are employed in matching circuits. For maximum RF-to-dc conversion efficiency in both low and high-power conditions, two different optimal loads are required, which is achieved from the load-modulation technique by using Bipolar Junction Transistor (BJT). The measurement result of the proposed rectifier shows more than 50% conversion efficiency for the power range -18 dB to 2 dBm and 8 dBm to 20 dBm with circuit size of 35 mm × 30 mm.

    DOI: 10.1109/WPTCE56855.2023.10216256

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  • Implementation of Low-Loss Sub-Terahertz Band Substrate Integrated Waveguide-based Interconnects and Cavities in CMOS Technology

    Thapa S.K., Pokharel R.K., Barakat A., Amakawa S., Dong R., Hara S., Watanabe I., Kasamatsu A.

    2023 35th General Assembly and Scientific Symposium of the International Union of Radio Science, URSI GASS 2023   2023年   ISBN:9789463968096

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    出版者・発行元:2023 35th General Assembly and Scientific Symposium of the International Union of Radio Science, URSI GASS 2023  

    Sub-terahertz (sub-THz) band low-loss on-chip substrate integrated waveguide (SIW)-based transmission line interconnects, and cavities are presented and implemented in complementary metal oxide semiconductor (CMOS) technology. SIW cavities are designed with standard and half-mode (HM) SIW structures. Similarly, low-loss SIW interconnect design is implemented by introducing complementary split ring resonators (CSRR) in HMSIW interconnects. The prototypes of the proposed SIW cavities and the interconnects structures are fabricated and experimented in 1P6M CMOS at 200 GHz band. The measurement results of designed SIW cavities present return loss better than 25 dB and the external quality (Q-) factor better than 130 from both designs. Similarly, the HMSIW interconnect presents a measured attenuation constant of less than 1.6 dB/mm at the frequency range of 130-220 GHz band. This works shows that on-chip low-loss SIW-based designs can be implemented in frequency bands like sub-THz and above and can find application for designing transmission lines, filters, oscillators, antennas, etc., for THz applications.

    DOI: 10.23919/URSIGASS57860.2023.10265470

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  • Capacitive Feedbacked Cold-Phase Compensator Analog Pre-Distorter and PAE Enhancer for K-Band CMOS PAs 査読

    Alngar O.Z., Barakat A., Pokharel R.K.

    IEEE Transactions on Circuits and Systems I: Regular Papers   69 ( 12 )   4969 - 4980   2022年9月   ISSN:1549-8328 eISSN:1558-0806

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IEEE Transactions on Circuits and Systems I: Regular Papers  

    A K-band two-stage power amplifier (PA) with capacitive-feedbacked cold-phase compensator (cold-PC) linearizer and power-added-efficiency (PAE) enhancer is introduced in 180-nm CMOS technology. This cold-PC consists of two parts. First, a cold-FET analog pre-distorter (APD) with a new capacitive-feedbacked technique is proposed to improve the linear behavior of the PA by enhancing the corresponding APD&#x2019;s compensation slope. The proposed implementation has a reduced insertion loss and a minimal chip area overhead. Second, a low-pass two-tunable inductive and capacitive PC is proposed to solve the phase shift problem at intermediate nodes that would enhance the PAE of the stacked-transistors configuration. The implemented PA achieves, at 23.5-GHz, a maximum measured PAE of 21.2&#37;, output power at the 1-dB compression point (OP<inline-formula> <tex-math notation="LaTeX">&#36;_{ ext{1dB } }&#36;</tex-math> </inline-formula>) of 13.4-dBm, and saturated output power of 15-dBm using a total chip area of 0.58 mm<inline-formula> <tex-math notation="LaTeX">&#36;^{ ext{2 } }&#36;</tex-math> </inline-formula>. Employing the proposed cold-PC results in a decrease of the measured error vector magnitude (EVM) of the 400-MHz 5G-NR of 64-QAM modulated signal and an increase of the OP<inline-formula> <tex-math notation="LaTeX">&#36;_{ ext{1dB } }&#36;</tex-math> </inline-formula> and its PAE by 2.5-dB and 7&#37;, respectively (enhancement by 78&#37; and 72&#37; from the original case, respectively), which, to the best of authors&#x2019; knowledge, is the highest reported enhancement of the linearizers of k-band PAs.

    DOI: 10.1109/TCSI.2022.3205367

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  • A High PAE Stacked K-band Power Amplifier Using π-Phase Compensation Technique 査読

    Alngar O.Z., Barakat A., Pokharel R.K.

    RFIT 2022 - 2022 IEEE International Symposium on Radio-Frequency Integration Technology   42 - 44   2022年8月   ISBN:9781665466493

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    記述言語:英語   掲載種別:研究論文(その他学術会議資料等)   出版者・発行元:RFIT 2022 - 2022 IEEE International Symposium on Radio-Frequency Integration Technology  

    A three-Tunable low-pass π-phase compensator technique is proposed and employed in a K-band CMOS power amplifier (PA) to solve the phase shift problem at intermediate nodes of stacked transistor configurations (STCs). Also, it reduces the effects of harmonic signals that in turns, enhances the overall power added efficiency (PAE) of the PA. The PA consists of two stages i.e. driver and main stages, designed using 2-STCs in 180-nm CMOS technology. The fabricated PA achieved a power gain of 12.8 dB at 23 GHz, a maximum PAE of 18.3&#37;, an output power of 1 dB compression point left(mathrm{P}{1 mathrm{~dB } }
    ight) of 14.1 1 dBm, and saturated output power left(mathrm{P}{ ext {sat } }
    ight) of 16.0 dBm while it consumes chip area of 0.604 mm2 including pads.

    DOI: 10.1109/RFIT54256.2022.9882403

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  • Study of Metamaterial on Efficiency of DGS-based MISO-WPT system 査読

    Maoqiang S., Jiang X., Aboualalaa M., Barakat A., Yoshitomi K., Pokharel R.K.

    2022 Wireless Power Week, WPW 2022 - Proceedings   344 - 348   2022年7月   ISBN:9781665484459

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    記述言語:その他   掲載種別:研究論文(その他学術会議資料等)   出版者・発行元:2022 Wireless Power Week, WPW 2022 - Proceedings  

    In this paper, we propose a multiple-input single-output (MISO) wireless power transfer (WPT) system using a stacked meta-surface structure for achieving a high transmission distance. We started by studying two coupled DGS resonators one is a transmitter and the other is a receiver, each resonator is excited by a microstrip line to transfer power at a frequency of 670 MHz. In order to improve the power transfer efficiency, five extra DGS transmitters are employed. Therefore, the proposed multiple-input transmitter is composed of six DGS resonators printed on one layer of a single substrate. On the other side, the receiver is a single DGS resonator. The size of the transmitter and receiver are 46.4mm × 30.7 mm and 15mm × 15 mm, respectively. The stacked meta-surface is in three layers. And the size of it is 25.4mm × 25 mm. In measurement, the WPT efficiency of the MISO system with meta-surface is a maximum of 31.1&#37; higher than that of the MISO system without meta-surface.

    DOI: 10.1109/WPW54272.2022.9853985

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  • Broadband and Compact 3-Bit Digitally-Controlled Reconfigurable Rectification Circuit 査読

    Gyawali B., Pokharel R.K., Thapa S.K., Aboualalaa M., Barakat A., Yoshitomi K.

    2022 Wireless Power Week, WPW 2022 - Proceedings   2022-January   780 - 783   2022年7月   ISBN:9781665484459

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    記述言語:その他   掲載種別:研究論文(その他学術会議資料等)   出版者・発行元:2022 Wireless Power Week, WPW 2022 - Proceedings  

    A broadband rectification circuit is usually designed with complex matching circuits to achieve decade and octave impedance which result is the bulkiness of the layout and increases the losses. To mitigate these problems, an ultra-wideband high-efficiency rectification circuit without any inductors and transmission lines at the input section [1] is utilized and employed with 3-bit digitally controlled signals to vary the length of a short stub at the grounding so that reconfigurable operation of the proposed rectifier is obtained in the frequency range of 60 MHz to 3.8 GHz. The proposed compact rectification circuit offers reconfigurable operation over a wide bandwidth and is best suitable for the applications in wirelessly powered multiband and software-defined radios or other portable devices.

    DOI: 10.1109/WPW54272.2022.9901332

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  • High PAE CMOS Power Amplifier With 44.4% FBW Using Superimposed Dual-Band Configuration and DGS Inductors 査読

    Alngar O.Z., Barakat A., Pokharel R.K.

    IEEE Microwave and Wireless Components Letters   32 ( 12 )   1423 - 1426   2022年7月   ISSN:1531-1309 eISSN:1558-1764

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IEEE Microwave and Wireless Components Letters  

    A two-stage 180-nm CMOS wideband (14&#x2013;22 GHz) power amplifier (PA) with a superimposed staggered technique and defected-ground-structure (DGS) inductors is introduced, where a wideband peaking main stage is designed at the center frequency; then, a superimposed dual-band (SDB) driver stage is proposed to obtain the optimally flat gain response over the whole bandwidth (BW). Also, DGS inductors are used to enhance the power added efficiency (PAE) of the implemented PA by decreasing the matching circuits&#x2019; insertion losses. The proposed PA achieved a power gain of 12 dB at a total chip area of 0.564 mm<inline-formula> <tex-math notation="LaTeX">&#36;^{2}&#36;</tex-math> </inline-formula>. Also, at the center frequency, it achieved a saturated output power of 16.6 dBm exhibiting the smallest reported amplitude-to-phase (AM-PM) distortion (2.1<inline-formula> <tex-math notation="LaTeX">&#36;^{circ})&#36;</tex-math> </inline-formula> and group delay (GD) variations (<inline-formula> <tex-math notation="LaTeX">&#36;pm&#36;</tex-math> </inline-formula>66 ps). Finally, it gives among the highest fractional bandwidth (FBW) (44.4&#37;) and the PAE (18.7&#37;) so far. Also, it achieves an error vector magnitude of <inline-formula> <tex-math notation="LaTeX">&#36;-&#36;</tex-math> </inline-formula>25 dB at 9.3-dBm output power for a 400-MHz 5G-NR signal.

    DOI: 10.1109/LMWC.2022.3189347

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  • Wideband Stacked Metamaterial for a Compact and Efficient Dual-band Wireless Power Transfer 査読

    Jiang X., Pokharel R.K., Barakat A., Yoshitomi K.

    IEEE MTT-S International Microwave Symposium Digest   2022-June   198 - 201   2022年6月   ISSN:0149-645X ISBN:9781665496131

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    記述言語:英語   掲載種別:研究論文(その他学術会議資料等)   出版者・発行元:IEEE MTT-S International Microwave Symposium Digest  

    A novel wideband stacked metamaterial is proposed for a dual-band wireless power transfer (WPT) system. Firstly, two types of split-ring resonators (SRRs) of different self-resonance frequencies are proposed. Then we sandwiched each type of the unit cell. Consequently, the proposed metamaterial exhibits wideband near-zero characteristics on both the real part and imaginary part of the permeability. Also, compared with conventional 1-D metamaterial [2], the proposed metamaterial can significantly empower both bands simultaneously of the dual-band WPT system. An experiment shows that the proposed metamaterial of size (20 mm x 20 mm 5.468 mm) has improved the efficiencies of both bands from 18.6&#37;, 22.9&#37; to 51.8&#37; and 47.8&#37;, respectively, at a wireless power transfer distance of 20 mm.

    DOI: 10.1109/IMS37962.2022.9865455

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  • On-Chip Millimeter-Wave DGS Based Bandstop Filter in 0.18-μm CMOS Process 査読 国際誌

    69 ( 6 )   2732 - 2736   2022年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    Defected Ground Structure (DGS) based on-chip bandstop filter (BSF) design is proposed for millimeter-wave applications. In the proposed structure, a capacitively loaded T-shape resonator is embedded in the original DGS resonator, which forms two high quality ( Q -) factor small loop resonators. Moreover, this structure, in combination with the feedline and series capacitor, independently realizes the position of two transmission poles: one at each side of the parallel resonance without increasing the layout size. The proposed BSF presents a sharp scattering (S-) parameter response due to the appearance of two transmission poles. As a result, the loaded Q -factor and negative group delay of the BSF are improved. The prototype of the proposed BSF is fabricated in 0.18- μm Complementary Metal-Oxide-Semiconductor (CMOS) process and measured. The measurement result shows a return loss of 1.78 dB at 53.2 GHz center stopband frequency with the negative group delay of 161 pS. The measurement results also agree well with the electromagnetic simulation results. Without pads, the active area of the prototyped BSF is only 0.024 mm2.

    DOI: 10.1109/TCSII.2022.3158995

    その他リンク: https://ieeexplore.ieee.org/document/9733395

  • Low Magnetic Loss Metamaterial Based Miniaturized WPT System for Biomedical Implants 査読

    Alshhawy S., Barakat A., Pokharel R.K., Yoshitomi K.

    IEEE MTT-S International Microwave Symposium Digest   2022-June   275 - 278   2022年6月   ISSN:0149-645X ISBN:9781665496131

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    記述言語:英語   掲載種別:研究論文(その他学術会議資料等)   出版者・発行元:IEEE MTT-S International Microwave Symposium Digest  

    We propose a low magnetic loss multi-ring resonator (MRR) metamaterial. Then, we utilize this MRR metamaterial in a stacked configuration as the WPT transmitter (TX) for a miniaturized receiver (RX) embedded in biomedical tissue. A prototype is fabricated, and the measurement shows an efficiency of 51&#37; at 50 MHz when the TX/RX separation distance is 9 mm. The TX/RX sizes are 20 mm × 20 mm and 7 mm × 7 mm, respectively. Hence, the proposed system has a figure-of- merit of 0.42, which is a significant improvement over the previously reported WPT systems. Also, the simulated specific absorption rate is within the recommended level when the input power is 21 dBm.

    DOI: 10.1109/IMS37962.2022.9865438

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  • Millimeter-Wave High Q-factor Sixteenth Mode SIW Cavity Resonator Implemented in 0.18-μm CMOS Technology 査読

    Thapa S.K., Pokharel R.K., Chen B., Fukuda T., Barakat A.

    IEEE MTT-S International Microwave Symposium Digest   2022-June   560 - 563   2022年6月   ISSN:0149-645X ISBN:9781665496131

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    記述言語:英語   掲載種別:研究論文(その他学術会議資料等)   出版者・発行元:IEEE MTT-S International Microwave Symposium Digest  

    Millimeter-wave miniaturized Substrate Integrated Waveguide (SIW) cavity resonator is proposed in 0.18-μm CMOS technology. Miniaturization of the SIW cavity resonator is achieved first by taking 1/16thparts of the standard SIW and employing folded ridge structure. Later this folded ridge sixteenth mode SIW cavity is inductively loaded by a complementary split-ring resonator, which provides internal matching within the cavity resonator. This improved matching enhances the return loss, the external Q-factor, and ultimately, the loaded Q-factor of the proposed cavity resonator. At 60 GHz resonance frequency, the fabricated prototype of the proposed cavity resonator presents a measured reflection coefficient of -33.42 dB, with the external Q- factor 112. Moreover, the active area of the fabricated cavity without measuring pads is only 0.019 mm2.

    DOI: 10.1109/IMS37962.2022.9865522

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  • On-Chip Millimeter-Wave DGS Based Bandstop Filter in 0.18-μm CMOS Process 査読

    69 ( 6 )   2732 - 2736   2022年6月

     詳細を見る

    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    Defected Ground Structure (DGS) based on-chip bandstop filter (BSF) design is proposed for millimeter-wave applications. In the proposed structure, a capacitively loaded T-shape resonator is embedded in the original DGS resonator, which forms two high quality ( &#36;{Q}&#36; -) factor small loop resonators. Moreover, this structure, in combination with the feedline and series capacitor, independently realizes the position of two transmission poles: one at each side of the parallel resonance without increasing the layout size. The proposed BSF presents a sharp scattering (S-) parameter response due to the appearance of two transmission poles. As a result, the loaded &#36;{Q}&#36; -factor and negative group delay of the BSF are improved. The prototype of the proposed BSF is fabricated in 0.18- &#36;mu ext{m}&#36; Complementary Metal-Oxide-Semiconductor (CMOS) process and measured. The measurement result shows a return loss of 1.78 dB at 53.2 GHz center stopband frequency with the negative group delay of 161 pS. The measurement results also agree well with the electromagnetic simulation results. Without pads, the active area of the prototyped BSF is only 0.024 mm2.

    DOI: 10.1109/TCSII.2022.3158995

  • Design of 50-GHz Low Phase Noise VCO Employing Two-Branches DGS Resonator in 0.18-μm CMOS Technology 査読

    Chen B., Pokharel R.K., Thapa S.K., Jahan N., Barakat A.

    IEEE Microwave and Wireless Components Letters   32 ( 10 )   1203 - 1206   2022年5月   ISSN:1531-1309 eISSN:1558-1764

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    記述言語:その他   掲載種別:研究論文(学術雑誌)   出版者・発行元:IEEE Microwave and Wireless Components Letters  

    This letter presents a &#36;V&#36; -band low phase noise voltage-controlled oscillator (VCO) design using a novel integrated two-branches defected ground structure (DGS) resonator in 0.18- &#36;mu ext{m}&#36; complementary metal-oxide-semiconductor (CMOS) technology. The proposed DGS resonator is realized in the top metal layer (M6) which has not only a higher quality factor than its predecessors but is also effective to reduce the length of interconnects. The measured carrier frequency and phase noise are 49 GHz and -122.05 dBc/Hz (-102.58 dBc/Hz) at 10-MHz (1-MHz) offset frequencies, respectively. The VCO core consumes 5.5 mW of dc power from the dc supply, which results in a figure of merit (FoM) of -189 dBc/Hz. The proposed VCO using the two-branches DGS resonator may give an alternative low-cost solution for designing a high-performance VCO or frequency synthesizer at &#36;V&#36; -band and beyond.

    DOI: 10.1109/LMWC.2022.3171405

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  • Design of 50-GHz Low Phase Noise VCO Employing Two-Branches DGS Resonator in 0.18- μm CMOS Technology 査読 国際誌

    2022年5月

     詳細を見る

    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    This letter presents a V-band low phase noise voltage-controlled oscillator (VCO) design using a novel integrated two-branches defected ground structure (DGS) resonator in 0.18-μm complementary metal-oxide-semiconductor (CMOS) technology. The proposed DGS resonator is realized in the top metal layer (M6) which has not only a higher quality factor than its predecessors but is also effective to reduce the length of interconnects. The measured carrier frequency and phase noise are 49 GHz and -122.05 dBc/Hz (-102.58 dBc/Hz) at 10-MHz (1-MHz) offset frequencies, respectively. The VCO core consumes 5.5 mW of dc power from the dc supply, which results in a figure of merit (FoM) of -189 dBc/Hz. The proposed VCO using the two-branches DGS resonator may give an alternative low-cost solution for designing a high-performance VCO or frequency synthesizer at V-band and beyond.

    DOI: https://doi.org/10.1109/LMWC.2022.3171405

    その他リンク: https://ieeexplore.ieee.org/document/9773303

  • Compact and Efficient WPT System to Embedded Receiver in Biological Tissues Using Cooperative DGS Resonators 査読

    Shimaa Alshhawy, Adel Barakat, Kuniaki Yoshitomi, Ramesh K. Pokharel

    IEEE Transactions on Circuits and Systems II: Express Briefs   69 ( 3 )   869 - 873   2022年3月

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    記述言語:その他   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1109/TCSII.2021.3123954

  • Compact and Efficient WPT System to Embedded Receiver in Biological Tissues Using Cooperative DGS Resonators 査読 国際誌

    #Shimaa Alshhawy; Adel Barakat; Kuniaki Yoshitomi; Ramesh K. Pokharel

    IEEE Transactions on Circuits and Systems II: Express Briefs   69 ( 3 )   869 - 873   2022年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1109/TCSII.2021.3123954

    その他リンク: https://ieeexplore.ieee.org/document/9594096

  • A W-Band Compact Substrate Integrated Waveguide Bandpass Filter With Defected Ground Structure in CMOS Technology 査読 国際誌

    #Baichuan Chen; #Samundra K. Thapa; Adel Barakat; Ramesh K. Pokharel

    IEEE Transactions on Circuits and Systems II: Express Briefs   69 ( 3 )   889 - 893   2022年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1109/TCSII.2021.3123655

    その他リンク: https://ieeexplore.ieee.org/document/9592631

  • A W-Band Compact Substrate Integrated Waveguide Bandpass Filter with Defected Ground Structure in CMOS Technology 査読

    Baichuan Chen, Samundra K. Thapa, Adel Barakat, Ramesh K. Pokharel

    IEEE Transactions on Circuits and Systems II: Express Briefs   69 ( 3 )   889 - 893   2022年3月

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    記述言語:その他   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1109/TCSII.2021.3123655

  • A W-Band 0.01 mm<sup>2</sup>Cavity Resonator Employing Slot-Loaded Shielded Folded Ridged Quarter-Mode in CMOS Technology 査読

    Chen B., Thapa S.K., Barakat A., Pokharel R.K.

    IEEE Microwave and Wireless Components Letters   32 ( 2 )   113 - 116   2022年2月   ISSN:1531-1309 eISSN:1558-1764

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IEEE Microwave and Wireless Components Letters  

    This letter proposes a W -band compact cavity resonator for future applications of on-chip bandpass filters (BPFs), oscillators, phase shifters, and so on. To mitigate the leakage from the open sides of a folded ridged quarter-mode substrate integrated waveguide (SIW) cavity, shielding structures made of vias are employed. Two parallel inductive slots are etched on the top metal layer for further size reduction. Later, the one-port cavity is converted to a two-port cavity resonator and utilized in the design of W -band BPF. The proposed design is implemented in a commercial complementary metal-oxide-semiconductor (CMOS) technology, fabricated, and measured. The active size of the proposed cavity resonator is only 99 mu text{m},,boldsymbol {times },,99,,mu text{m} ( 0.054 boldsymbol {lambda }-{mathbf {g } },,{ boldsymbol {times } },,0.054{} boldsymbol {lambda }-{mathbf {g } } ), and the measured insertion loss ( vert S-{21}vert ) is 2.26 dB.

    DOI: 10.1109/LMWC.2021.3122149

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    その他リンク: https://ieeexplore.ieee.org/document/9599586

  • A Compact Millimeter-Wave On-chip DGS-based Bandstop Filter with Two Transmission Poles in CMOS Technology

    Thapa S.K., Chen B., Barakat A., Pokharel R.K.

    2022 52nd European Microwave Conference, EuMC 2022   564 - 567   2022年   ISBN:9782874870699

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    出版者・発行元:2022 52nd European Microwave Conference, EuMC 2022  

    A compact size millimeter-wave on-chip defected ground structure (DGS)-based bandstop filter (BSF) is proposed and implemented in 0.18-μm CMOS technology. The proposed BSF is realized with T-shape DGS. In combination with the series resonance circuits, the proposed design realizes two transmission poles: one at either side of parallel resonance. Despite the compact size, the proposed BSF still maintains higher quality (Q) factors and group delay. The proposed BSF optimized at 52 GHz frequency is fabricated and tested. The active area of the fabricated prototype without pads is 0.0129 mm2 which is only 50% of the size of a wideband BSF recently proposed in a similar technology [8] and [16]. The measured loaded and unloaded Q-factors are 4.57 and 20.55, respectively.

    DOI: 10.23919/EuMC54642.2022.9924382

    Scopus

  • Design of Self-Impedance Matching Ultra-Wideband Rectification Circuit

    Gyawali B., Thapa S.K., Aboualalaa M., Barakat A., Yoshitomi K., Pokharel R.K.

    Asia-Pacific Microwave Conference Proceedings, APMC   2022-November   671 - 673   2022年   ISBN:9784902339567

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    出版者・発行元:Asia-Pacific Microwave Conference Proceedings, APMC  

    An ultrawideband rectifier without an external impedance matching circuit offers many benefits, such as compact circuit size and lower losses. Generally, the rectifier is designed using the conventional voltage doubler circuit, which has varying input impedance for the operating frequency. But, to achieve the wideband rectification, the input impedance of the proposed circuit must be matched with 50 O impedance throughout the desired frequency band. For varying impedance, it is challenging to design the impedance matching network. In [11], the idea of a virtual DC battery is utilized to achieve ultra-wideband rectification without using any external matching at input section. For the further improvement of rectification efficiency, in this work, parallel diode connection is proposed instead of single diode. The proposed design achieved maximum flat conversion efficiency for energy harvesting and wireless power transfer applications.

    Scopus

  • Efficacy of Transmission Poles Characteristics on K-Band VCOs Phase Noise Reduction

    Jahan N., Barakat A., Pokharel R.

    Asia-Pacific Microwave Conference Proceedings, APMC   2022-November   668 - 670   2022年   ISBN:9784902339567

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    出版者・発行元:Asia-Pacific Microwave Conference Proceedings, APMC  

    In this paper, effectiveness of multi-resonance around the parallel resonance of an LC-tank circuit on the reduction of K-band Voltage-Controlled Oscillators (VCOs) phase noise is proposed. The skirt characteristics of the Scattering (|S|) parameters of the resonators is sharpened by introducing transmission poles beside the parallel resonance of the LC-tank circuit. In return, an enhanced the resonator loaded quality (Q) factor without compromising the unloaded Q-factor is obtained. Three designs are realized, verified and compared to the others in a differential VCO topology and the phase noise reduction in post-layout simulations is confirmed. Finally, two chips are fabricated in 0.18-µm CMOS technology and measured.

    Scopus

  • Experimental Study on the Effect of Feeding Topology of 60 GHz Sixteenth Mode SIW Cavity Resonator in CMOS Technology

    Thapa S.K., Baichuan C., Barakat A., Pokharel R.K.

    Asia-Pacific Microwave Conference Proceedings, APMC   2022-November   384 - 386   2022年   ISBN:9784902339567

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    出版者・発行元:Asia-Pacific Microwave Conference Proceedings, APMC  

    Millimeter-wave compact, high quality (Q-) Substrate Integrated Waveguide (SIW) cavity is proposed in 0.18-µm CMOS technology. Compact size of the SIW cavity resonator is achieved first by taking 1/16th parts of the standard SIW and employing folded ridge structure. Two prototypes of the proposed cavity resonator with different feeding structures were fabricated and measured. The measurement results present a reflection coefficient lower than -22 dB and the external Q-factor greater than 60 in both cases. Experimentally, it is verified that due to the low losses associated with the top feed structure, it presents better return losses and Q-factor than the transition feed structure. Moreover, the active area of the fabricated cavity resonators without measuring pads are only 0.024 mm2, which is only 0.563% when compared to the standard SIW cavity.

    Scopus

  • Analysis and design of diode physical limit bandwidth efficient rectification circuit for maximum flat efficiency, wide impedance, and efficiency bandwidths 査読

    Babita Gyawali, Samundra K. Thapa, Adel Barakat, Kuniaki Yoshitomi, Ramesh K. Pokharel

    Scientific Reports   11 ( 1 )   2021年12月

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    記述言語:その他   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1038/s41598-021-99405-7

  • A multimode metamaterial for a compact and robust dualband wireless power transfer system 査読

    Xin Jiang, Ramesh K. Pokharel, Adel Barakat, Kuniaki Yoshitomi

    Scientific Reports   11 ( 1 )   2021年12月

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    記述言語:その他   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1038/s41598-021-01677-6

    その他リンク: https://www.nature.com/articles/s41598-021-01677-6

  • Efficient and Compact Dual-band Wireless Power Transfer System through Biological Tissues Using Dual-Reference DGS Resonators 査読

    Xin Jiang, Fairus Tahar, Takashi Miyamoto, Adel Barakat, Kuniaki Yoshitomi, Ramesh K. Pokharel

    IEEE MTT-S International Microwave Symposium Digest   2021-June   54 - 57   2021年6月

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    記述言語:その他   掲載種別:研究論文(その他学術会議資料等)  

    DOI: 10.1109/IMS19712.2021.9574938

  • Design of three layers-stacked metasurface and its application to compact dual-band WPT system 査読

    Xin Jiang, Fairus Tahar, Takashi Miyamotol, Adel Barakat, Kuniaki Yoshitomi, Ramesh K. Pokharel

    2021 IEEE Wireless Power Transfer Conference, WPTC 2021   2021年6月

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    記述言語:英語   掲載種別:研究論文(その他学術会議資料等)  

    DOI: 10.1109/WPTC51349.2021.9458177

  • X-Band Feedback Type Miniaturized Oscillator Design with Low Phase Noise Based on Eighth Mode SIW Bandpass Filter 査読

    Samundra K. Thapa, Baichuan Chen, Adel Barakat, Kuniaki Yoshitomi, Ramesh K. Pokharel

    IEEE Microwave and Wireless Components Letters   31 ( 5 )   485 - 488   2021年5月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1109/LMWC.2021.3064602

  • Design of Low Phase Noise VCO Considering C/L Ratio of LC Resonator in 0.18-μm CMOS Technology 査読 国際誌

    68 ( 12 )   3513 - 3517   2021年5月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    A voltage-controlled oscillator (VCO) is usually designed by maximizing the quality (Q-) factor of the LC-tank resonator to realize a low phase noise. For the same frequency, the ratio of C/L affects the loaded Q-factor (QL) and then phase noise of the VCO. This affect has not been considered so far in the design of VCO because the conventional on-chip spiral inductor cannot be optimized for C/L ratio. This brief first investigates the effects of C/L ratio on the phase noise, and a design methodology for optimized C/L ratio using defected ground structure (DGS) resonator is presented. Then, the resonators were further evaluated based on LgL-product simulation for a fixed Ibias. Employing the proposed resonator, a very low phase noise KUband VCO is designed and implemented in 0.18-lm CMOS technology. The measurement result shows that the proposed VCO has a phase noise of -110.77 dBc/Hz at 1 MHz offset of 17.5 GHz carrier frequency and a frequency tuning range of 8.7&#37;. The VCO consumes 2.3 mW power, which results in a figure of merit (FoM) of -191.95 dB.

    DOI: 10.1109/TCSII.2021.3079309

    その他リンク: https://ieeexplore.ieee.org/document/9428594

  • Wireless power transfer system rigid to tissue characteristics using metamaterial inspired geometry for biomedical implant applications 査読

    Ramesh K. Pokharel, Adel Barakat, Shimaa Alshhawy, Kuniaki Yoshitomi, Costas Sarris

    Scientific Reports   11 ( 1 )   2021年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1038/s41598-021-84333-3

  • Simultaneous Wireless Power and Information Transfer Using Coupled Co-Existing Defected Ground Structure Resonators 査読

    Adel Barakat, Shimaa Alshhawy, Kuniaki Yoshitomi, Ramesh K. Pokharel

    IEEE Transactions on Circuits and Systems II: Express Briefs   68 ( 2 )   632 - 636   2021年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1109/TCSII.2020.3016385

  • Miniaturized Slot-Loaded SIW Resonator and Its Application to C-band Low Phase Noise Oscillator 査読

    Samundra K. Thapa, Baichuan Chen, Adel Barakat, Kuniaki Yoshitomi, Ramesh K. Pokharel

    2020 50th European Microwave Conference, EuMC 2020   161 - 164   2021年1月

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    記述言語:英語   掲載種別:研究論文(その他学術会議資料等)  

    DOI: 10.23919/EuMC48046.2021.9338129

  • Improvement of Magnetic Field for Near-Field WPT System Using Two Concentric Open-Loop Spiral Resonators 査読

    Mohamed Aboualalaa, Islam Mansour, Adel Barakat, Kuniaki Yoshitomi, Ramesh K. Pokharel

    IEEE Microwave and Wireless Components Letters   30 ( 10 )   993 - 996   2020年10月

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    記述言語:その他   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1109/LMWC.2020.3016136

  • High isolation simultaneous wireless power and information transfer system using coexisting DGS resonators and Figure-8 Inductors 査読

    Adel Barakat, Ramesh K. Pokharel, Shimaa Alshhawy, Kuniaki Yoshitomi, Shigeo Kawasaki

    IEEE MTT-S International Microwave Symposium Digest   2020-August   1172 - 1175   2020年8月

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    記述言語:英語   掲載種別:研究論文(その他学術会議資料等)  

    DOI: 10.1109/IMS30576.2020.9223866

  • Analysis and Implementation of High-Q CT Inductor for Compact and Wide- Tuning Range Ku-Band VCO 査読

    Islam Mansour, Mohamed Aboualalaa, Adel Barakat, Ahmed Allam, Adel B. Abdel-Rahman, Mohammed Abo-Zahhad, Ramesh K. Pokharel

    IEEE Microwave and Wireless Components Letters   30 ( 8 )   802 - 805   2020年8月

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    DOI: 10.1109/LMWC.2020.3004753

  • Utilization of Multi-Resonant Defected Ground Structure Resonators in the Oscillator Feedback for Phase Noise Reduction of K-Band VCOs in 0.18-μ m CMOS Technology 査読

    67 ( 4 )   1115 - 1125   2020年4月

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    記述言語:その他   掲載種別:研究論文(学術雑誌)  

    This work proposes a new theory to reduce the phase noise of K-band Voltage-Controlled Oscillators (VCOs) in Complementary Metal Oxide Semiconductor (CMOS) process by introducing one or more transmission poles around the parallel resonance of an LC-tank circuit. Introduction of transmission poles beside the parallel resonance of the LC-tank circuit sharpens the skirt characteristics of the Scattering (S) parameters of the resonators. In return, sharp S-parameters slope enhances the resonator loaded quality (Q) factor without compromising the unloaded Q-factor. In addition, the transmission pole can be realized near the second harmonic of the oscillation. This allocation of the transmission pole leads to the cancellation of this second harmonic and a further reduction of the phase noise. The proposed theory is verified by three different designs based on defected ground structure (DGS) resonators. These designs realized a low-band transmission pole before the parallel resonance, a high-band transmission pole after the parallel resonance, and dual-band transmission poles around the parallel resonance. First, each design is verified and compared to the others using circuit and electromagnetic simulations to establish the Q-factor improvement. Then, each of the resonators is utilized in a differential VCO topology and the phase noise reduction in post-layout simulations is confirmed. Finally, two chips are fabricated in 0.18-μ m CMOS technology and measured. The measurement results are in good agreement with the simulations, which confirm our claim about the proposed theory.

    DOI: 10.1109/TCSI.2020.2965007

  • A −192.7-dBc/Hz FOm K<inf>u</inf>-band VCO using a DGS resonator with a high-band transmission pole in 0.18-μm CMOS technology 査読

    29 ( 12 )   814 - 817   2019年12月

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    記述言語:その他   掲載種別:研究論文(学術雑誌)  

    This letter presents the improvement of the phase noise (PN) of a voltage-controlled oscillator (VCO) by using a defected ground structure (DGS) resonator with a high-band transmission pole. The proposed DGS resonator has two loops in a coplanar stripline topology. The outer loop is loaded by a series capacitance, which produces the high-band transmission pole. The overall combination has a parallel capacitor to generate the necessary parallel resonance for the VCO operation. This proposed DGS resonator has a sharper impedance and frequency response slope, which results in an improved quality factor. In return, utilization of this DGS resonator into a KU-Band VCO reduces its PN. The prototyped VCO in 0.18-µm CMOS oscillates at 15.52 GHz and shows a PN of −111.27 and −134.07 dBc/Hz at 1- and 10-MHz offset, respectively, while consuming 3.3-mW power. The VCO has a frequency tuning range of 9.5&#37;, which results in a figure of merit (FoM) of −192.7 dB.

    DOI: 10.1109/LMWC.2019.2950525

  • Experimental study of the effect of interconnects on phase noise of K-band VCO in 0.18μm CMOS technology 査読

    2019-December   1670 - 1672   2019年12月

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    記述言語:その他   掲載種別:研究論文(その他学術会議資料等)  

    In this paper, to characterize the effect of interconnects inductance on VCO's phase noise precisely, two K-band VCO circuits that employ DGS as an inductor are designed and analyzed. It's shown that not only the quality factor of the inductor in resonator has a significant effect on VCO's phase noise, the parasitic inductance of the interconnecting transmission lines will also inflect the phase noise severely. To get the Quantitative analysis, a K-band (25 GHz) VCO is implemented in the 0.18-mu mathrm{m} 1P6M CMOS process and measured.

    DOI: 10.1109/APMC46564.2019.9038781

  • Separation-Misalignment Insensitive WPT System Using Two-Plane Printed Inductors 査読

    Shimaa Alshhawy, Adel Barakat, Kuniaki Yoshitomi, Ramesh K. Pokharel

    IEEE Microwave and Wireless Components Letters   29 ( 10 )   683 - 686   2019年10月

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    DOI: 10.1109/LMWC.2019.2935621

  • Design and implementation of dual-mode inductors for dual-band wireless power transfer systems 査読

    Adel Barakat, Kuniaki Yoshitomi, Ramesh K. Pokharel

    IEEE Transactions on Circuits and Systems II: Express Briefs   66 ( 8 )   1287 - 1291   2019年8月

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    記述言語:その他   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1109/TCSII.2018.2883671

  • A New Compact Dual-Band Wireless Power Transfer System Using Interlaced Resonators 査読

    Ramy Sharaf, Adel B. Abdel-Rahman, Anwer S.Abd El-Hameed, Adel Barakat, Sherif Hekal, Ahmed Allam

    IEEE Microwave and Wireless Components Letters   29 ( 7 )   498 - 500   2019年7月

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    DOI: 10.1109/LMWC.2019.2917747

  • 45&#37; RF-to-DC Conversion Efficiency Wireless Power Transfer System Through Biological Tissues Using Complex Conjugate Impedance Matching Taking Account of Tissue's Properties 査読

    Sumin Chalise, Mitsuki Nakao, Fairus Tahar, Adel Barakat, Kuniaki Yoshitomi, Ramesh K. Pokharel

    IEEE MTT-S International Microwave Symposium Digest   2019-June   1419 - 1422   2019年6月

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    DOI: 10.1109/mwsym.2019.8700821

  • Triple-Band Near-Field Wireless Power Transfer System Using Coupled Defected Ground Structure Band Stop Filters 査読

    Adel Barakat, Shimaa Alshhawy, Kuniaki Yoshitomi, Ramesh K. Pokharel

    IEEE MTT-S International Microwave Symposium Digest   2019-June   1411 - 1414   2019年6月

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    DOI: 10.1109/mwsym.2019.8700853

  • Dual-Band Defected Ground Structure Resonators Wireless Power Transfer System Connected to Voltage-Doubler Circuit 査読

    Fairus Tahar, Sumin Chalise, Adel Barakat, Kuniaki Yoshitomi, Ramesh K. Pokharel

    2019 IEEE Topical Conference on Wireless Sensors and Sensor Networks, WiSNet 2019   2019年5月

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    DOI: 10.1109/WISNET.2019.8711815

  • Analysis and application of dual series resonances for low phase noise K-band VCO design in 0.18-μm CMOS technology 査読

    2019-May   2019年5月

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    記述言語:その他   掲載種別:研究論文(その他学術会議資料等)  

    This work proposes a new theory to improve the phase noise of a Voltage-Controlled Oscillator (VCO) by introducing dual series resonances around the parallel resonance of an LC-tank circuit. The overall circuit has an improved susceptance slope parameters, which results in the improvement of quality (Q-) factor. Later, its effectiveness is demonstrated to design a low phase noise K-band VCO. The proposed characteristics are realized by a compact defected ground structure (DGS) resonator in a coplanar strip line (CPS) topology. The DGS is loaded by a capacitor, and this combination introduces the parallel resonance. The CPS signal line is implemented with high characteristic impedance to introduce a series inductance. Then, a gap in the CPS is introduced with a loading series capacitance forming a series resonance circuit with the CPS inductance. The overall combination of the series and parallel resonance circuits allowed the targeted two series resonances before and after the parallel resonance. The design is implemented in 0.18-μm CMOS technology, and the post-layout simulation shows that the VCO has a phase noise of -112.31 dBc/Hz @1 MHz offset of 22.07 GHz oscillation, which is 2.3 dB improvement compared to single series resonance VCO. The VCO consumes 4 mW power resulting in a figure of merit (FoM) of -193.2 dB.

    DOI: 10.1109/ISCAS.2019.8702264

  • Compact Dual-Band Wireless Power Transfer Using Overlapped Single Loop Defected Ground Structure 査読

    Fairus Tahar, Sumin Chalise, Kuniaki Yoshitomi, Adel Barakat, Ramesh K. Pokharel

    2018 IEEE Wireless Power Transfer Conference, WPTC 2018   2019年2月

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    DOI: 10.1109/WPT.2018.8639281

  • High FOM Dual Band Wireless Power Transfer using Bow-tie Defected Ground Structure Resonators 査読

    M. R. Saad, Fairus Tahar, Sumin Chalise, Adel Barakat, Kuniaki Yoshitomi, Ramesh K. Pokharel

    2018 IEEE Wireless Power Transfer Conference, WPTC 2018   2019年2月

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    DOI: 10.1109/WPT.2018.8639134

  • Design of multi-layers DGS resonator for phase noise improvement of K-Band VCOs in 0.18 µm CMOS technology 査読

    2018-August   178 - 181   2019年1月

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    記述言語:その他   掲載種別:研究論文(その他学術会議資料等)  

    A novel technique for a low phase noise and compact K-band Voltage-Controlled Oscillator (VCO) using multi-layers DGS resonator is proposed. The proposed DGS resonator realizes an additional series resonance at the higher side of parallel resonance frequency, and this results in improving both the active and loaded quality factor of the resonator. The proposed resonator has active quality factor of 130 and a compact size of 0.009 mm 2 (0.000459 ? 2 ). Using the proposed DGS resonator in the VCO causes 9 dB improvement in the phase noise compared the VCO implemented using the conventional LC resonator. Two VCOs are designed using the method to illustrate the effect of the series resonance. The first VCO is designed three layers DGS resonator and the other VCO using two layers DGS resonator. The designs are implemented in 0.18 µm CMOS technology and consume 2.9 mW power, and from the post layout results, the first proposed VCO oscillates from 19.6 to 21.3 GHz (8.3 &#37;) and has a phase noise of -113.2 dBc/Hz at 1 MHz offset frequency, and this results in the figure of merit (FoM) and FoM taking account of the tuning range to be -194.4 and -192.7 dB, respectively. The second VCO has a tuning range of 6.1 &#37; and phase noise of -114 dBc/Hz @ 1 MHz offset at 19.6 GHz oscillation.

    DOI: 10.1109/MWSCAS.2018.8623874

  • Performance enhancement of 60 GHz CMOS band pass filter employing oxide height virtual increase 査読

    Nessim Mahmoud, Adel Barakat, Mohamed E. Nasr, Ramesh K. Pokharel

    Progress In Electromagnetics Research M   77   125 - 134   2019年1月

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    記述言語:その他   掲載種別:研究論文(学術雑誌)  

    DOI: 10.2528/pierm18101608

  • Design of Low-Loss Coplanar Transmission Lines Using Distributed Loading for Millimeter-Wave Power Divider/Combiner Applications in 0.18-μm CMOS Technology 査読

    66 ( 12 )   5221 - 5229   2018年12月

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    This paper presents a new type of a low-loss miniaturized coplanar-waveguide (CPW) transmission line (TL) by employing distributed loading, capacitors and inductors, in 0.18-μm complementary metal-oxide-semiconductor (CMOS) technology. The capacitors are realized by vertical parallel plates made of vias, and a group of open stubs inserted to the signal line, whereas the inductors are realized by high impedance lines. Then, the proposed CPW-TL is employed to design a miniaturized millimeter wave ultra-wideband low-loss Wilkinson power divider/combiner (WPD/C). The proposed distributed loading results in reducing each WPD/C arm length by more than 50&#37; without changing its characteristic impedance and insertion loss (IL). The design is fabricated in 0.18-μm CMOS technology and tested. The measured results show a wideband performance from dc to 67 GHz with 1-dB IL and isolation greater than 15 dB from 36 to 67 GHz. In addition, the fabricated WPD/C achieves an excellent amplitude imbalance and phase imbalance of less than 0.16 dB and 0.45°, respectively. The core chip size is 336 × 165 μm 2 , which is almost 32.8&#37; compact compared to the recently proposed WPD in the same technology.

    DOI: 10.1109/TMTT.2018.2873381

  • Dual Resonance Circuits by Defected Ground Structure Resonators for Low Phase Noise K-Band CMOS VCO 査読

    Ramesh K. Pokharel, Nusrat Jahan, Adel Barakat

    2018 IEEE International Symposium on Radio-Frequency Integration Technology, RFIT 2018   2018年11月

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    DOI: 10.1109/RFIT.2018.8524088

  • Design Approach for Efficient Wireless Power Transfer Systems during Lateral Misalignment 査読

    Adel Barakat, Kuniaki Yoshitomi, Ramesh K. Pokharel

    IEEE Transactions on Microwave Theory and Techniques   66 ( 9 )   4170 - 4177   2018年9月

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    DOI: 10.1109/TMTT.2018.2852661

  • Ultracompact CMOS 60-GHz Tapped-Line Combline BPF with Two Transmission Zeros Using Defected Ground Structures 査読

    Elsayed Elsaidy, Adel Barakat, Adel B. Abdel-Rahman, Ahmed Allam, Ramesh K. Pokharel

    IEEE Transactions on Components, Packaging and Manufacturing Technology   8 ( 9 )   1642 - 1649   2018年9月

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    DOI: 10.1109/TCPMT.2018.2861411

  • Degree of freedom to select coupling coefficent and quality factor in near-field wireless power transfer: A case study of using DGS Structures 査読

    Ramesh K. Pokharel, Adel Barakat, Fairus Tahar, Sherif Hekal

    IEEE MTT-S International Microwave and RF Conference, IMaRC 2017   87 - 89   2018年8月

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    DOI: 10.1109/IMaRC.2017.8449719

  • High-Efficiency CMOS RF-to-DC Rectifier Based on Dynamic Threshold Reduction Technique for Wireless Charging Applications 査読

    Manal M. Mohamed, Ghazal A. Fahmy, Adel B. Abdel-Rahman, Ahmed Allam, Adel Barakat, Mohammed Abo-Zahhad, Hongting Jia, Ramesh K. Pokharel

    IEEE Access   6   46826 - 46832   2018年8月

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    DOI: 10.1109/ACCESS.2018.2866457

  • High efficiency wireless power transfer system using spiral DGS resonators through biological tissues 査読

    Sumin Chalise, F. Tahar, M. R. Saad, A. Baraket, Kuniaki Yoshitomi, R. K. Pokharel

    IMBioc 2018 - 2018 IEEE/MTT-S International Microwave Biomedical Conference   43 - 45   2018年8月

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    記述言語:その他   掲載種別:研究論文(その他学術会議資料等)  

    DOI: 10.1109/IMBIOC.2018.8428951

  • A K-Band VCO Employing High Active Q-factor Defected Ground Structure Resonator in 0.18pm CMOS Technology 査読

    Nusrat Jahan, Chen Baichuan, Ramesh K. Pokharel, Adel Barakat

    Proceedings - IEEE International Symposium on Circuits and Systems   2018-May   2018年4月

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    記述言語:その他   掲載種別:研究論文(その他学術会議資料等)  

    DOI: 10.1109/ISCAS.2018.8351670

  • 22-GHz-Band Oscillator Using Integrated H-Shape Defected Ground Structure Resonator in 0.18-μ m CMOS Technology 査読

    28 ( 3 )   233 - 235   2018年3月

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    記述言語:その他   掲載種別:研究論文(学術雑誌)  

    A novel 22-GHz-band oscillator using an integrated defected ground structure (DGS) resonator is presented for quasi-millimeter waveband applications. The DGS is etched on the first metal layer (M1) below a 50-Ω microstrip line on the top metal layer (M6) of 0.18-μm one-poly six-metal (1P6M) complementary metal-oxide-semiconductor (CMOS) technology. The proposed oscillator is fabricated using 0.18-μm CMOS technology, and the measured carrier frequency and phase noise are 22.88 GHz and-129.21 dBc/Hz (-108.05 dBc/Hz) at 10-MHz (1 MHz) offset frequency, respectively. The power dissipation is 6 mW that results in a figure of merit to be-188.8 dB. As the DGS resonator could be designed at any high frequency, it may give an alternative design approach of high performance voltage controlled oscillator and frequency synthesizers at K-band and beyond, thus alleviates the problem of self-resonance that a spiral inductor usually encounters at higher frequency.

    DOI: 10.1109/LMWC.2018.2801031

  • Broadband printed-dipole antenna for future 5G applications and wireless communication 査読

    Anwer S.Abd El-Hameed, Adel Barakat, Adel B. Abdel-Rahman, Ahmed Allam, Ramesh K. Pokharel, Kuniaki Yoshitomi

    IEEE Radio and Wireless Symposium, RWS   2018-January   106 - 108   2018年2月

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    記述言語:その他   掲載種別:研究論文(その他学術会議資料等)  

    DOI: 10.1109/RWS.2018.8304959

  • Dual-Band Defected Ground Structures Wireless Power Transfer System With Independent External and Inter-Resonator Coupling 査読

    Fairus Tahar, Adel Barakat, Redzuan Saad, Kuniaki Yoshitomi, Ramesh K. Pokharel

    IEEE Transactions on Circuits and Systems II: Express Briefs   64 ( 12 )   1372 - 1376   2017年12月

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    記述言語:その他   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1109/TCSII.2017.2740401

  • Ku-band oscillator using integrated defected ground structure resonator in 0.18μm CMOS technology 査読

    2017-January   763 - 766   2017年12月

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    記述言語:その他   掲載種別:研究論文(その他学術会議資料等)  

    In the paper, we propose a novel voltage-controlled oscillator (VCO) employing defected ground structure (DGS) band stop filter (BSF). The VCO operates from 15.24 GHz to 15.86 GHz. A square shaped DGS etched at the lowest metal layer (M1) below 50-Ohm microstrip line on the top metal layer (M6) of 0.18 μm 1P6M CMOS process. The proposed square-shaped DGS resonator achieves smaller size and higher quality factor than those of a conventional spiral inductor resonator at Ku band frequency. The power dissipation of the VCO is 4 mW. The measured carrier frequency and phase noise are 15.76 GHz and-127.57 dBc/Hz (104.25 dBc/Hz) at 10 MHz (1 MHz) offset frequency, respectively. The measured figure of merit (FoM) is 182.9 dB. The fabricated chip core VCO size is only 0.084mm2 which increases figure of merit (FoMa) to 194 dB.

    DOI: 10.23919/EuMC.2017.8230959

  • 1.06 FoM and Compact Wireless Power Transfer System Using Rectangular Defected Ground Structure Resonators 査読

    F. Tahar, R. Saad, A. Barakat, R. K. Pokharel

    IEEE Microwave and Wireless Components Letters   27 ( 11 )   1025 - 1027   2017年11月

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    記述言語:その他   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1109/LMWC.2017.2750032

  • Design and Application of Virtual Inductance of Square-Shaped Defected Ground Structure in 0.18-&#36;mu ext{m}&#36; CMOS Technology 査読

    Nusrat Jahan, Siti Amalina Enche Ab Rahim, Adel Barakat, Takana Kaho, Ramesh K. Pokharel

    IEEE Journal of the Electron Devices Society   5 ( 5 )   299 - 305   2017年9月

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    記述言語:その他   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1109/JEDS.2017.2728686

  • Ultracompact 60-GHz CMOS BPF Employing Broadside-Coupled Open-Loop Resonators 査読

    Anwer S.Abd El-Hameed, Adel Barakat, Adel B. Abdel-Rahman, Ahmed Allam, Ramesh K. Pokharel

    IEEE Microwave and Wireless Components Letters   27 ( 9 )   818 - 820   2017年9月

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    記述言語:その他   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1109/LMWC.2017.2734771

  • Analysis of near field wireless power transfer using bow-tie defected ground structure 査読

    M. R. Saad, Fairus Tahar, Adel Barakat, Kuniaki Yoshitomi, Ramesh K. Pokharel

    Asia-Pacific Microwave Conference Proceedings, APMC   495 - 498   2017年6月

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    記述言語:その他   掲載種別:研究論文(その他学術会議資料等)  

    DOI: 10.1109/APMC.2017.8251489

  • Study of phase noise improvement of K-band VCO using additional series resonance realized by DGS resonator on CMOS technology 査読

    Nusrat Jahan, Adel Barakat, Ramesh K. Pokharel

    Asia-Pacific Microwave Conference Proceedings, APMC   1014 - 1017   2017年6月

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    記述言語:その他   掲載種別:研究論文(その他学術会議資料等)  

    DOI: 10.1109/APMC.2017.8251624

  • Simple design approach for asymmetric resonant inductive coupled WPT systems using J-inverters 査読

    Adel Barakat, Sherif Hekal, Ramesh K. Pokharel

    Asia-Pacific Microwave Conference Proceedings, APMC   2017年5月

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    記述言語:英語   掲載種別:研究論文(その他学術会議資料等)  

    DOI: 10.1109/APMC.2016.7931382

  • Low insertion loss 60 GHz CMOS H-shaped resonator BPF 査読

    Adel Barakat, Nessim Mahmoud, Ramesh K. Pokharel

    IEEE Radio and Wireless Symposium, RWS   187 - 189   2017年3月

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    記述言語:その他   掲載種別:研究論文(その他学術会議資料等)  

    DOI: 10.1109/RWS.2017.7885983

  • 60 GHz CMOS circular patch antenna-on-chip 査読

    Adel Barakat, Ahmed Allam, Adel B. Abdel-Rahman, Hala Elsadek, Ramesh K. Pokharel, Aimeric Bisognin, Cyril Luxey

    Microwave Journal   60 ( 2 )   90 - 100   2017年2月

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    記述言語:その他   掲載種別:研究論文(学術雑誌)  

  • A Novel Technique for Compact Size Wireless Power Transfer Applications Using Defected Ground Structures 査読

    Sherif Hekal, Adel B. Abdel-Rahman, Hongting Jia, Ahmed Allam, Adel Barakat, Ramesh K. Pokharel

    IEEE Transactions on Microwave Theory and Techniques   65 ( 2 )   591 - 599   2017年2月

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    記述言語:その他   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1109/TMTT.2016.2618919

  • Design of 5.5GHz LC oscillator using distributed grid of N-well in P-substrate inductor 査読

    S. A.Enche Ab Rahim, Adel Barakat, Ramesh K. Pokharel

    2016 IEEE Asia Pacific Conference on Circuits and Systems, APCCAS 2016   262 - 264   2017年1月

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    記述言語:その他   掲載種別:研究論文(その他学術会議資料等)  

    DOI: 10.1109/APCCAS.2016.7803949

  • Compact Wireless Power Transfer System Using Defected Ground Bandstop Filters 査読

    Sherif Hekal, Adel B. Abdel-Rahman, Hongting Jia, Ahmed Allam, Adel Barakat, Takano Kaho, Ramesh K. Pokharel

    IEEE Microwave and Wireless Components Letters   26 ( 10 )   849 - 851   2016年10月

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    記述言語:その他   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1109/LMWC.2016.2601300

  • Asymmetric wireless power transfer systems using coupled DGS resonators 査読

    Sherif Hekal, Adel B. Abdel-Rahman, Ahmed Allam, Hongting Jia, Adel Barakat, Ramesh K. Pokharel

    IEICE Electronics Express   13 ( 21 )   2016年10月

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    記述言語:その他   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1587/elex.13.20160591

  • Compact Size On-Chip 60 GHz H-Shaped Resonator BPF 査読

    Nessim Mahmoud, Adel Barakat, Adel B. Abdel-Rahman, Ahmed Allam, Ramesh K. Pokharel

    IEEE Microwave and Wireless Components Letters   26 ( 9 )   681 - 683   2016年9月

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    記述言語:その他   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1109/LMWC.2016.2597219

  • Improving the Quality Factor of Inductor in Si-Substrate by Introducing Fully Depleted PN-junctions 査読

    Siti Amalina Enche Ab Bahim, Adel Barakat, Ramesh Kumar Pokharel

    Research Reports on Information Science and Electrical Engineering of Kyushu University   21 ( 2 )   45 - 48   2016年7月

     詳細を見る

    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    その他リンク: http://jairo.nii.ac.jp/0001/00389403

  • Improving the quality factor of inductor in Si-substrate by introducing fully depleted PN-junctions 査読

    Siti Amalina Enche Ab Rahim, Adel Barakat, Ramesh K. Pokharel

    Research Reports on Information Science and Electrical Engineering of Kyushu University   21 ( 2 )   45 - 51   2016年7月

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    記述言語:その他   掲載種別:研究論文(学術雑誌)  

  • Asymmetric strongly coupled printed resonators for wireless charging applications 査読

    Sherif Hekal, Adel B. Abdel-Rahman, Ahmed Allam, Adel Barakat, Hongting Jia, Ramesh K. Pokharel

    2016 IEEE 17th Annual Wireless and Microwave Technology Conference, WAMICON 2016   2016年6月

     詳細を見る

    記述言語:その他   掲載種別:研究論文(その他学術会議資料等)  

    DOI: 10.1109/WAMICON.2016.7483829

  • Radiation performance enhancement of a 60 GHz CMOS Quasi-Yagi antenna 査読

    Elsayed Elsaidy, Adel Barakat, Adel B. Abdel-Rahman, Ahmed Allam, Ramesh K. Pokharel

    2016 IEEE 17th Annual Wireless and Microwave Technology Conference, WAMICON 2016   2016年6月

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    記述言語:その他   掲載種別:研究論文(その他学術会議資料等)  

    DOI: 10.1109/WAMICON.2016.7483819

  • A 60-GHz on-chip tapered slot Vivaldi antenna with improved radiation characteristics 査読

    Anwer S.Abd El-Hameed, Nessim Mahmoud, Adel Barakat, Adel B. Abdel-Rahman, Ahmed Allam, Ramesh K. Pokharel

    2016 10th European Conference on Antennas and Propagation, EuCAP 2016   2016年5月

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    記述言語:その他   掲載種別:研究論文(その他学術会議資料等)  

    DOI: 10.1109/EuCAP.2016.7481426

  • 60 GHz on-chip mixed coupled BPF with H-shaped defected ground structures 査読 国際誌

    A. Barakat, R. Pokharel, T. Kaho

    Electronics Letters   52 ( 7 )   533 - 535   2016年4月

     詳細を見る

    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1049/el.2015.4465

  • Miniaturized low loss 60 GHz CMOS mixed coupled BPF with patterned ground shield 査読 国際誌

    Adel Barakat, Muhammad Hanif, Ramesh K. Pokharel

    Microwave and Optical Technology Letters   58 ( 3 )   697 - 699   2016年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1002/mop.29650

  • Performance enhancement of 0.18μm CMOS on chip bandpass filters using H-shaped parasitic element 査読

    2016-March   303 - 306   2016年3月

     詳細を見る

    記述言語:英語   掲載種別:研究論文(その他学術会議資料等)  

    A design of an improved open loop resonator on-chip bandpass filter for 60 GHz millimeter-wave applications using 0.18 μm CMOS technology is presented. The proposed on-chip BPF employs H-shaped parasitic structure inserted between two open loop coupled resonator. The adoption of a two open loop coupled resonators BPF and the utilization of two transmissions zero located at 48 and 80 GHz permit a compact size and high selectivity of the BPF. In addition, the parasitic H-shaped structure increases the capacitance between the two resonators, which enables a further reduction of the physical length of the filter and enhances the coupling between the resonators which improve the filter insertion loss. The proposed BPF has a center frequency of 60 GHz, an insertion loss of-2 dB, a 3dB band width of 13 GHz, and a core size 160 × 480 μm2 with total chip size 680 × 280 μm2 (including bonding pads).

    DOI: 10.1109/ICM.2015.7438049

  • A60-GHz double-Y balun-fed on-chip Vivaldi antenna with improved gain 査読

    Anwer S.Abd El-Hameed, Adel Barakat, Adel B. Abdel-Rahman, Ahmed Allam, Ramesh K. Pokharel

    Proceedings of the International Conference on Microelectronics, ICM   2016-March   307 - 310   2016年3月

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    記述言語:英語   掲載種別:研究論文(その他学術会議資料等)  

    DOI: 10.1109/ICM.2015.7438050

  • Study of SiO<inf>2</inf> thickness effect on insertion loss of CMOS 60 GHz band pass filter 査読

    Nessim Mahmoud, Adel Barakat, Anwer S.Abd El-Hameed, Adel B. Abdel-Rahman, Ahmed Allam, Ramesh K. Pokharel

    Proceedings of the IEEE International Conference on Electronics, Circuits, and Systems   2016-March   237 - 239   2016年3月

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    記述言語:その他   掲載種別:研究論文(その他学術会議資料等)  

    DOI: 10.1109/ICECS.2015.7440292

  • Improved gain 60GHz CMOS antenna with N-well grid 査読

    Adel Barakat, Ahmed Allam, Hala Elsadek, Adel B. Abdel-Rahman, Ramesh K. Pokharel, Takana Kaho

    IEICE Electronics Express   13 ( 5 )   2016年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1587/elex.13.20151115

  • A gain enhanced 60 GHz CMOS antenna-on-chip using off-chip Mu near zero metamaterial lens 査読

    M. Hanif, R. K. Pokharel, K. Yoshitomi, Adel Barakat, Hala Elsadek

    Proceedings of the 2015 IEEE 4th Asia-Pacific Conference on Antennas and Propagation, APCAP 2015   355 - 357   2016年1月

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    記述言語:その他   掲載種別:研究論文(その他学術会議資料等)  

    DOI: 10.1109/APCAP.2015.7374402

  • Miniaturized 60 GHz triangular CMOS Antenna-on-Chip using asymmetric artificial magnetic conductor 査読

    Adel Barakat, Ahmed Allam, Hala Elsadek, Adel B. Abdel-Rahman, S. Muhammad Hanif, Ramesh K. Pokharel

    2015 IEEE 15th Topical Meeting on Silicon Monolithic Integrated Circuits in RF Systems, SiRF 2015   92 - 94   2015年6月

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    記述言語:その他   掲載種別:研究論文(その他学術会議資料等)  

    DOI: 10.1109/SIRF.2015.7119885

  • Small size 60 GHz CMOS Antenna-on-Chip: Gain and efficiency enhancement using asymmetric Artificial Magnetic Conductor 査読

    Adel Barakat, Ahmed Allam, Hala Elsadek, Haruichi Kanaya, Ramesh K. Pokharel

    European Microwave Week 2014: Connecting the Future, EuMW 2014 - Conference Proceedings; EuMC 2014: 44th European Microwave Conference   104 - 107   2014年12月

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    記述言語:その他   掲載種別:研究論文(その他学術会議資料等)  

    DOI: 10.1109/EuMC.2014.6986380

  • Back radiation reduction of 60 GHz CMOS slot Antenna-on-Chip (AoC) using Artificial Dielectric Layer (ADL) for Area Reuse 査読

    Adel Barakat, Ahmed Allam, Hala Elsadek, Haruichi Kanaya, Hongting Jia, Kuniaki Yoshitomi, Ramesh Pokharel

    2014 USNC-URSI Radio Science Meeting (Joint with AP-S Symposium), USNC-URSI 2014 - Proceedings   137   2014年11月

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    記述言語:その他   掲載種別:研究論文(その他学術会議資料等)  

    DOI: 10.1109/USNC-URSI.2014.6955519

  • Compact size high gain AoC using rectangular AMC in CMOS for 60 GHz millimeter wave applications 査読

    Adel Barakat, Ahmed Allam, Ramesh K. Pokharel, Hala Elsadek, Mohamed El-Sayed, Keiji Yoshida

    IEEE MTT-S International Microwave Symposium Digest   2013年6月

     詳細を見る

    記述言語:その他   掲載種別:研究論文(その他学術会議資料等)  

    DOI: 10.1109/MWSYM.2013.6697475

  • 60 GHz triangular monopole Antenna-on-Chip over an Artificial Magnetic Conductor 査読

    Adel Barakat, Ahmed Allam, Ramesh K. Pokharel, Hala Elsadek, Mohamed El-Sayed, Keiji Yoshida

    Proceedings of 6th European Conference on Antennas and Propagation, EuCAP 2012   972 - 976   2012年3月

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    記述言語:その他   掲載種別:研究論文(その他学術会議資料等)  

    DOI: 10.1109/EuCAP.2012.6206127

  • Performance optimization of a 60 GHz antenna-on-chip over an artificial magnetic conductor 査読

    Adel Barakat, Ahmed Allam, Ramesh K. Pokharel, Hala Elsadek, Mohamed El-Sayed, Keiji Yoshida

    Proceedings of the 2012 Japan-Egypt Conference on Electronics, Communications and Computers, JEC-ECC 2012   118 - 121   2012年3月

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    記述言語:その他   掲載種別:研究論文(その他学術会議資料等)  

    DOI: 10.1109/JEC-ECC.2012.6186968

  • Bandwidth extension of UWB planar antenna with band-notched characteristics 査読

    Adel Barakat, Mostafa El-Khamy

    MECAP'10, 1st Middle East Conference on Antennas and Propagation   2010年10月

     詳細を見る

    記述言語:その他   掲載種別:研究論文(その他学術会議資料等)  

    DOI: 10.1109/MECAP.2010.5724184

▼全件表示

講演・口頭発表等

  • Simple design approach for asymmetric resonant inductive coupled WPT systems using J-inverters 国際会議

    ADEL Barakat, POKHAREL RAMESH KUMAR, Sherif Hekal

    2016 Asia Pacific Microwave Conference (APMC)  2016年12月 

     詳細を見る

    開催年月日: 2016年12月

    記述言語:英語   会議種別:シンポジウム・ワークショップ パネル(公募)  

    国名:インド  

    その他リンク: http://ieeexplore.ieee.org/document/7931382/

  • Radiation performance enhancement of a 60 GHz CMOS Quasi-Yagi antenna 国際会議

    Elsayed Elsaidy, ADEL Barakat, Adel B. Abdel-Rahman, Ahmed Allam, POKHAREL RAMESH KUMAR

    2016 IEEE 17th Annual Wireless and Microwave Technology Conference (WAMICON)  2016年4月 

     詳細を見る

    開催年月日: 2016年4月 - 2016年5月

    記述言語:英語   会議種別:口頭発表(一般)  

    国名:アメリカ合衆国  

    その他リンク: http://ieeexplore.ieee.org/document/7483819/

  • Asymmetric strongly coupled printed resonators for wireless charging applications 国際会議

    Sherif hekal, Adel B. Abdel-Rahman, Ahmed Allam, ADEL Barakat, JIA HONGTING, POKHAREL RAMESH KUMAR

    2016 IEEE 17th AnnualWireless and Microwave Technology Conference (WAMICON)  2016年4月 

     詳細を見る

    開催年月日: 2016年4月

    記述言語:英語   会議種別:口頭発表(一般)  

    国名:アメリカ合衆国  

    その他リンク: http://ieeexplore.ieee.org/document/7483829/

  • A 60-GHz on-chip tapered slot Vivaldi antenna with improved radiation characteristics 国際会議

    Anwer S. Abd El-Hameed, Nessim Mahmoud, ADEL Barakat, Adel B. Abdel-Rahman, Ahmed Allam, POKHAREL RAMESH KUMAR

    2016 10th European Conference on Antennas and Propagation (EuCAP)  2016年4月 

     詳細を見る

    開催年月日: 2016年4月

    記述言語:英語   会議種別:口頭発表(一般)  

    国名:スイス連邦  

    その他リンク: http://ieeexplore.ieee.org/document/7481426/

  • Performance enhancement of 0.18µm CMOS on chip bandpass filters using H-shaped parasitic element 国際会議

    2015年12月 

     詳細を見る

    開催年月日: 2015年12月

    記述言語:英語   会議種別:口頭発表(一般)  

    国名:モロッコ王国  

    A design of an improved open loop resonator on-chip bandpass filter for 60 GHz millimeter-wave applications using 0.18 μm CMOS technology is presented. The proposed on-chip BPF employs H-shaped parasitic structure inserted between two open loop coupled resonator. The adoption of a two open loop coupled resonators BPF and the utilization of two transmissions zero located at 48 and 80 GHz permit a compact size and high selectivity of the BPF. In addition, the parasitic H-shaped structure increases the capacitance between the two resonators, which enables a further reduction of the physical length of the filter and enhances the coupling between the resonators which improve the filter insertion loss. The proposed BPF has a center frequency of 60 GHz, an insertion loss of -2 dB, a 3dB band width of 13 GHz, and a core size 160×480 μm2 with total chip size 680×280 μm2 (including bonding pads).

    その他リンク: http://ieeexplore.ieee.org/document/7438049/

  • A60-GHz double-Y balun-fed on-chip Vivaldi antenna with improved gain 国際会議

    Anwer S. Abd El-Hameed, ADEL Barakat, Adel B. Abdel-Rahman, Ahmed Allam, POKHAREL RAMESH KUMAR

    2015 27th International Conference on Microelectronics (ICM)  2015年12月 

     詳細を見る

    開催年月日: 2015年12月

    記述言語:英語   会議種別:口頭発表(一般)  

    国名:モロッコ王国  

    その他リンク: http://ieeexplore.ieee.org/document/7438050/

  • Study of SiO2 thickness effect on insertion loss of CMOS 60 GHz band pass filter 国際会議

    Nessim Mahmoud, Adel Barakat, Anwer S. Abd El-Hameed, Adel B. Abdel-Rahman, Ahmed Allam, Ramesh Kumar Pokharel

    2015 IEEE International Conference on Electronics, Circuits, and Systems (ICECS)  2015年12月 

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    開催年月日: 2015年12月

    記述言語:英語   会議種別:シンポジウム・ワークショップ パネル(公募)  

    国名:エジプト・アラブ共和国  

    その他リンク: http://ieeexplore.ieee.org/document/7440292/

  • A gain enhanced 60 GHz CMOS antenna-on-chip using off-chip Mu near zero metamaterial lens 国際会議

    2015 IEEE 4th Asia-Pacific Conference on Antennas and Propagation (APCAP)  2015年7月 

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    開催年月日: 2015年6月 - 2015年7月

    記述言語:英語   会議種別:口頭発表(一般)  

    国名:インドネシア共和国  

    その他リンク: http://ieeexplore.ieee.org/document/7374402/

  • Miniaturized 60 GHz triangular CMOS Antenna-on-Chip using asymmetric artificial magnetic conductor 国際会議

    Adel Barakat, Ahmed Allam, Hala Elsadek, Adel B. Abdel-Rahman, S. Muhammad Hanif, Ramesh K. Pokharel

    2015 IEEE 15th Topical Meeting on Silicon Monolithic Integrated Circuits in RF Systems (SiRF)  2015年1月 

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    開催年月日: 2015年1月

    記述言語:英語  

    国名:アメリカ合衆国  

    その他リンク: http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=7119885&abstractAccess=no&userType=inst

  • Small size 60 GHz CMOS Antenna-on-Chip: Gain and efficiency enhancement using asymmetric Artificial Magnetic Conductor 国際会議

    Adel Barakat, Ahmed Allam, Hala Elsadek, Haruichi Kanaya, Ramesh K. Pokharel

    2014 44th European Microwave Conference (EuMC)  2014年10月 

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    開催年月日: 2014年10月

    記述言語:英語   会議種別:口頭発表(一般)  

    国名:イタリア共和国  

    その他リンク: http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=6986380&abstractAccess=no&userType=inst

  • Back radiation reduction of 60 GHz CMOS slot Antenna-on-Chip (AoC) using Artificial Dielectric Layer (ADL) for Area Reuse 国際会議

    Adel Barakat, Ahmed Allam, Hala Elsadek, Haruichi Kanaya, Hongting Jia, Kuniaki Yoshitomi, Ramesh Pokharel

    2014 USNC-URSI Radio Science Meeting (Joint with AP-S Symposium)  2014年7月 

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    開催年月日: 2014年7月

    記述言語:英語   会議種別:口頭発表(一般)  

    国名:アメリカ合衆国  

    その他リンク: http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=6955519&abstractAccess=no&userType=inst

  • Compact size high gain AoC using rectangular AMC in CMOS for 60 GHz millimeter wave applications 国際会議

    Adel Barakat, Ahmed Allam, Ramesh K. Pokharel, Hala Elsadek, Mohammed Ragab, Keji Yoshida

    2013 IEEE MTT-S International Microwave Symposium Digest (IMS)  2013年6月 

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    開催年月日: 2013年6月

    記述言語:英語   会議種別:口頭発表(一般)  

    国名:アメリカ合衆国  

    その他リンク: http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=6697475

  • 60 GHz triangular monopole Antenna-on-Chip over an Artificial Magnetic Conductor 国際会議

    Adel Barakat, Ahmed Allam, Ramesh K. Pokharel, Hala Elsadek, Mohammed Ragab, Keji Yoshida

    2012 6th European Conference on Antennas and Propagation (EUCAP)  2012年3月 

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    開催年月日: 2012年3月

    記述言語:英語   会議種別:口頭発表(一般)  

    国名:チェコ共和国  

    その他リンク: http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=6206127&abstractAccess=no&userType=inst

  • Performance optimization of a 60 GHz Antenna-on-Chip over an Artificial Magnetic Conductor 国際会議

    Adel Barakat, Ahmed Allam, Ramesh K. Pokharel, Hala Elsadek, Mohammed Ragab, Keji Yoshida

    2012 Japan-Egypt Conference on Electronics, Communications and Computers (JEC-ECC)  2012年3月 

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    開催年月日: 2012年3月

    記述言語:英語   会議種別:口頭発表(一般)  

    国名:エジプト・アラブ共和国  

    その他リンク: http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=6186968&abstractAccess=no&userType=inst

  • Bandwidth extension of UWB planar antenna with band-notched characteristics 国際会議

    Adel Barakat, Mostafa ElKhamy

    2010年10月 

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    開催年月日: 2010年10月

    記述言語:英語   会議種別:口頭発表(一般)  

    国名:エジプト・アラブ共和国  

    その他リンク: http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=5724184&abstractAccess=no&userType=inst

  • Stacked Metamaterial Based Wireless Power Transfer System for Biomedical Implant Applications 招待 国際会議

    Adel Barakat

    International Japan-Africa Conference on Elctronics, Communications, and Computations (JAC_ECC 2022)  2022年12月 

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    開催年月日: 2022年12月

    記述言語:英語   会議種別:口頭発表(招待・特別)  

    国名:エジプト・アラブ共和国  

  • Design Methodology of Wide Tuning Range DGS-based VCO for K-band Applications in 0.18-µm CMOS Technology 国際会議

    2022年4月 

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    開催年月日: 2022年4月

    記述言語:英語   会議種別:口頭発表(一般)  

    開催地:London   国名:グレートブリテン・北アイルランド連合王国(英国)  

    Recently, defected ground structure (DGS) resonators have been employed to design a low phase noise Voltage-Controlled Oscillator (VCO) for quasi-millimeter wave applications [10]. A few advantages of such VCOs are that a DGS resonator has a higher Q-factor than an on-chip spiral inductor, and it has a higher self-resonance frequency compared to a conventional LC resonator so that a stable inductance value with respect to the frequency can be realized. However, one of its drawbacks is that the tuning range of DGS-based VCOs is limited. In this paper, a method to realize a wide tuning range of DGS-based VCOs has been proposed using two interconnected DGS resonators. As a result, the designed VCO implemented in 0.18-µm 1P6M CMOS technology achieves a 19.8% tuning range with the best phase noise performance of -109.43dBc/Hz at 1-MHz offset frequency in simulations. The experiment result shows that the fabricated VCO has a phase noise of -108.41dBc/Hz at 1-MHz offset frequency with the carrier frequency of 18.51GHz, which exhibits good agreement with the simulation.

    その他リンク: https://ieeexplore.ieee.org/document/9783689

  • A 100GHz Bandpass Filter Employing Shielded Folded Ridged Quarter-Mode SIW Resonator in CMOS Technology 国際会議

    #Baichuan Chen; #Samundra K. Thapa; Adel Barakat; Ramesh K. Pokharel

    2021 51st European Microwave Conference (EuMC)  2022年4月 

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    開催年月日: 2022年4月

    記述言語:英語   会議種別:口頭発表(一般)  

    国名:グレートブリテン・北アイルランド連合王国(英国)  

    その他リンク: https://ieeexplore.ieee.org/document/9784336

  • Metamaterial Inspired Geometries for Wireless Power Transfer to Biomedical Implants 招待 国際会議

    Ramesh Pokharel; Adel Barakat; Costas Sarris

    2021 51st European Microwave Conference (EuMC)  2022年4月 

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    開催年月日: 2022年4月

    記述言語:英語   会議種別:口頭発表(一般)  

    国名:グレートブリテン・北アイルランド連合王国(英国)  

    その他リンク: https://ieeexplore.ieee.org/document/9784207

  • Stacked Metasurfaces for Misalignment Improvement of WPT System Using Spiral Resonators 国際会議

    #Yutaro Ikeda; #Xin Jiang; Mohamed Aboualalaa; Adel Barakat; Kuniaki Yoshitomi; Ramesh K. Pokharel

    2021 51st European Microwave Conference (EuMC)  2022年4月 

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    開催年月日: 2022年4月

    記述言語:英語   会議種別:口頭発表(一般)  

    国名:グレートブリテン・北アイルランド連合王国(英国)  

    その他リンク: https://ieeexplore.ieee.org/document/9784281

  • Design of Compact and High Q-Factor W-Band Cavity in 0.18-µm CMOS Technology 国際会議

    2022年4月 

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    開催年月日: 2022年4月

    記述言語:英語   会議種別:口頭発表(一般)  

    開催地:London   国名:グレートブリテン・北アイルランド連合王国(英国)  

    This paper proposes a compact, high quality (Q-) factor cavity in commercial CMOS technology for terahertz band applications. The proposed cavity consists of a folded quarter-mode substrate integrated waveguide (QMSIW) topology. It also outlines some guidelines for creating layouts with specific foundries, particularly for building vertical walls using an array of vias. The cavity was implemented in 0.18 µm CMOS technology and measurements were taken. The measurements showed that the resonant frequency and reflection coefficient were 96.9 GHz and -30.14 dB, respectively, in good agreement with the simulation results. The area of the proposed cavity was 0.0506 mm2 without measurement pads, which is only 2.4% and 8.9% when compared to the standard full-mode SIW cavity and the recently proposed 87 GHz.

    その他リンク: https://ieeexplore.ieee.org/document/9784193

  • Efficient and Compact Dual-band Wireless Power Transfer System through Biological Tissues Using Dual-Reference DGS Resonators 国際会議

    #Xin Jiang; Fairus Tahar; #Takashi Miyamoto; Adel Barakat; Kuniaki Yoshitomi; Ramesh K. Pokharel

    2021 IEEE MTT-S International Microwave Symposium (IMS)  2021年6月 

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    開催年月日: 2021年6月

    記述言語:英語   会議種別:口頭発表(一般)  

    国名:アメリカ合衆国  

    その他リンク: https://ieeexplore.ieee.org/document/9574938

  • Design of Three Layers-Stacked Metasurface and Its Application to Compact Dual-band WPT System 国際会議

    #Xin Jiang; Fairus Tahar; #Takashi Miyamotol; Adel Barakat; Kuniaki Yoshitomi; Ramesh K. Pokharel

    2021 IEEE Wireless Power Transfer Conference (WPTC)  2021年6月 

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    開催年月日: 2021年6月

    記述言語:英語   会議種別:口頭発表(一般)  

    国名:アメリカ合衆国  

    その他リンク: https://ieeexplore.ieee.org/document/9458177

  • Miniaturized Slot-Loaded SIW Resonator and Its Application to C-band Low Phase Noise Oscillator 国際会議

    #Samundra K. Thapa; #Baichuan Chen; Adel Barakat; Kuniaki Yoshitomi; Ramesh K. Pokharel

    2020 50th European Microwave Conference (EuMC)  2021年1月 

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    開催年月日: 2021年1月

    記述言語:英語   会議種別:口頭発表(一般)  

    国名:オランダ王国  

    その他リンク: https://ieeexplore.ieee.org/document/9338129

  • Low insertion loss 60 GHz CMOS H-shaped resonator BPF 国際会議

    ADEL Barakat, POKHAREL RAMESH KUMAR, Nessim Mahmoud

    2017 IEEE Radio and Wireless Symposium (RWS)  2017年1月 

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    開催年月日: 2017年1月

    記述言語:英語   会議種別:口頭発表(一般)  

    国名:アメリカ合衆国  

    その他リンク: http://ieeexplore.ieee.org/document/7885983/

  • Design of 5.5GHz LC oscillator using distributed grid of N-well in P-substrate inductor 招待 国際会議

    S.A Enche Ab Rahim, Adel Barakat, Ramesh Kumar Pokharel

    2016 IEEE Asia Pacific Conference onCircuits and Systems (APCCAS)  2016年10月 

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    開催年月日: 2016年10月

    記述言語:英語   会議種別:口頭発表(一般)  

    国名:大韓民国  

    その他リンク: http://ieeexplore.ieee.org/document/7803949/

▼全件表示

MISC

  • Author Correction: A multimode metamaterial for a compact and robust dualband wireless power transfer system (Scientific Reports, (2021), 11, 1, (22125), 10.1038/s41598-021-01677-6)

    Jiang X., Pokharel R.K., Barakat A., Yoshitomi K.

    Scientific Reports   12 ( 1 )   2022年12月

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    出版者・発行元:Scientific Reports  

    The original version of this Article contained errors in the Acknowledgements section.“This work was supported in part by JSPS KAKENHI Grant number: 21K04178, in part by the MIC/SCOPE Grant number: 21452069, in part by the Foundation for Technology Promotion for Electronic Circuit Board, and in part by a research granted from The Murata Science Foundation.” now reads: “This work was supported in part by the MIC/SCOPE Grant Number: JP215010003, in part by JSPS KAKENHI Grant Numbers: 21K04178, in part by the Foundation for Technology Promotion for Electronic Circuit Board, and in part by a research grant from The Murata Science Foundation.” The original Article has been corrected.

    DOI: 10.1038/s41598-022-09238-1

    Scopus

  • Author Correction: Analysis and design of diode physical limit bandwidth efficient rectification circuit for maximum flat efficiency, wide impedance, and efficiency bandwidths (Scientific Reports, (2021), 11, 1, (19941), 10.1038/s41598-021-99405-7)

    Gyawali B., Thapa S.K., Barakat A., Yoshitomi K., Pokharel R.K.

    Scientific Reports   12 ( 1 )   2022年12月

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    出版者・発行元:Scientific Reports  

    The original version of this Article contained an error in the Acknowledgements section. “This work was supported in part by JSPS KAKENHI Grant Number: 21K04178, in part by the MIC/SCOPE Grant Number: 21452069, in part by the Foundation for Technology Promotion for Electronic Circuit Board, and in part by a research grant from The Murata Science Foundation.” now reads: “This work was supported in part by the MIC/SCOPE Grant Number: JP215010003, in part by JSPS KAKENHI Grant Number: 21K04178, in part by the Foundation for Technology Promotion for Electronic Circuit Board, and in part by a research grant from The Murata Science Foundation.” The original Article has been corrected.

    DOI: 10.1038/s41598-022-09087-y

    Scopus

  • B-1-105 メタマテリアルカバーを用いた60GHz帯用のオンチップアンテナの設計(B-1.アンテナ・伝播B(アンテナ一般),一般セッション)

    電子情報通信学会総合大会講演論文集   2015年2月

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    記述言語:日本語  

所属学協会

  • IEEE

  • EuMA

学術貢献活動

  • 学術論文等の審査

    役割:査読

    2023年

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    種別:査読等 

    外国語雑誌 査読論文数:13

  • 学術論文等の審査

    役割:査読

    2022年

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    種別:査読等 

    外国語雑誌 査読論文数:22

  • Organization Committee Member 国際学術貢献

    International Japan-Africa Conference on Electronics, Communications and Computations 2021  ( Virtual (online) Egypt ) 2021年12月

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    種別:大会・シンポジウム等 

    参加者数:150

  • 学術論文等の審査

    役割:査読

    2021年

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    種別:査読等 

    外国語雑誌 査読論文数:10

    国際会議録 査読論文数:2

共同研究・競争的資金等の研究課題

  • 回転体計測における誘導給電と高速データ通信技術に関する研究

    2023年1月 - 2024年3月

    共同研究

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    担当区分:研究分担者  資金種別:その他産学連携による資金

  • Coupling Independent metamaterial-based wireless power and data transfer system over a single channel for biomedical applications

    研究課題/領域番号:22K14260  2022年 - 2024年

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Early-Career Scientists

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    担当区分:研究代表者  資金種別:科研費

  • メタマテリアル支援小型・高効率無線電力伝送システムによる体内への電力と情報の無線伝送システムの研究開発

    研究課題/領域番号:JP215010003  2021年 - 2023年

    科学研究費助成事業  総務省

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    担当区分:研究分担者  資金種別:科研費以外の競争的資金

  • New metamaterial for efficient and compact WPT system for biological applications

    研究課題/領域番号:21K20430  2021年 - 2022年

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Research Activity start-up

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    担当区分:研究代表者  資金種別:科研費

  • 公益財団法人 村田学術振興財団/Development of Stacked Metamaterial-based WPT System to Embedded in-Body Sensors and Devices

    2021年

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    資金種別:寄附金

担当授業科目

  • (IUPE)Linear Circuits I

    2023年10月 - 2023年12月   秋学期

FD参加状況

  • 2023年9月   役割:参加   名称:【シス情FD】価値創造型半導体人材育成センターについて

    主催組織:部局

  • 2023年7月   役割:講演   名称:【シス情FD】若手教員の研究紹介⑨

    主催組織:部局