Naoki Sakai

J-GLOBAL         Last updated: Nov 9, 2018 at 10:47
 
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Name
Naoki Sakai
Affiliation
Toyohashi University of Technology

Research Areas

 
 

Awards & Honors

 
Aug 2017
Young Scientist Award, The International Union of Radio Science 2017 General Assembly and Scientific Symposium
 
Mar 2010
Excellent Student Award, IEEE Nagoya Section
 

Published Papers

 
Sonshu Sakihara, Satoshi Kitabayashi, Naoki Sakai, Takashi Ohira
IEICE Transactions on Fundamentals   E101-A(2)    Feb 2018   [Refereed]
SAKIHARA Sonshu, TAKANA Masaru, SAKAI Naoki, OHIRA Takashi
IEICE Transactions on Electronics   100(10) 918-923   2017   [Refereed]
<p>This paper presents an approach to nonlinear impedance measurement exploiting an oscilloscope and Möbius transformation. Proposed system consists of a linear 4-port network and an oscilloscope. One of the port is excited by a high power source....
崎原孫周, 鈴木良輝, 坂井尚貴, 大平孝
電子情報通信学会論文誌 C(Web)   J99-C(4) 142-149 (WEB ONLY)   Apr 2016   [Refereed]
鈴木良輝, 崎原孫周, 坂井尚貴, 大平孝, 遠藤哲夫, 藤岡友美
電子情報通信学会論文誌 C(Web)   J99-C(4) 133-141 (WEB ONLY)   Apr 2016   [Refereed]
YAMADA Kyohei, SAKAI Naoki, OHIRA Takashi
IEICE Transactions on Electronics (Web)   E99.C(10) 1182‐1189(J‐STAGE)   2016   [Refereed]
和泉政史, 大森陽介, 南昂孝, 坂井尚貴, 大平孝
電子情報通信学会論文誌 C(Web)   J98-C(12) 403-411 (WEB ONLY)   Dec 2015   [Refereed]
佐藤翔一, 斉藤彰, 水谷豊, 坂井尚貴, 大平孝
電子情報通信学会論文誌 B(Web)   J98-B(9) 948-957 (WEB ONLY)   Sep 2015   [Refereed]
佐藤翔一, 斉藤彰, 水谷豊, 坂井尚貴, 大平孝
電子情報通信学会論文誌 C(Web)   J97-C(12) 549-553 (WEB ONLY)   Dec 2014   [Refereed]
Suzuki Yoshiki, Mizutani Minoru, Sugiura Takamitsu, Sakai Naoki, Ohira Takashi
IEEJ Transactions on Industry Applications   134(7) 675-682   2014   [Refereed]
Electric vehicles (EVs) are expected to play a leading role in the changeover from fossil fuels to clean energy. However, EVs are currently not very popular. This is because of their short cruising distance and long charging time. Wireless power t...
SAKAI Naoki, ODA Yasuaki, WUREN Tuya, UEHARA Hideyuki, OHIRA Takashi
The transactions of the Institute of Electronics, Information and Communication Engineers. B   96(9) 1057-1066   Sep 2013   [Refereed]
無線秘密鍵生成共有方式のための小型可変指向性アンテナとして,USBスティック型エスパアンテナを設計及び試作する.はじめに,指向性複雑性指標である前後比(FBR),軌跡長(LLL),及び可変指向性多様性指標であるリアクタンス領域指向性相関係数(RDC)を定義,それらを用いて3素子ダイポールエスパアンテナの解析及び実験検証する.素子間隔がλ/16 (λは自由空間波長),リアクタンス範囲は-25〜10Ωで多様な可変指向性性能が得られる.これに基づきUSBスティック型エスパアンテナを試作,評価する...
SAKAI Naoki, ODA Yasuaki, WUREN Tuya, UEHARA Hideyuki, OHIRA Takashi
The transactions of the Institute of Electronics, Information and Communication Engineers. B   96(9) 936-944   Sep 2013   [Refereed]
無線秘密鍵生成共有方式の秘匿性を高める可変指向性アンテナを設計するため,アンテナ指向性多様性指標を提案,秘匿性とアンテナ指向性多様性の関係について示す.アンテナ指向性多様性指標として制御パラメータ領域指向性相関係数(Parameter Domain Correlation coefficient: PDC)を提案する.送受信する素波を1対1に対応づけるTRBC (Transmit-Receive Beamlet Correspondence)伝搬環境で指向性の選択により秘匿性が受ける影響を...

Conference Activities & Talks

 
Proposal of inverse Doherty rectifier tolerant of DC load fluctuation
N. Sakai, Y. Miyazaki, S. Abe, and T. Ohira
32nd URSI GASS   Aug 2017   
Sandwiched parallel plate capacitive coupler for wireless power transfer tolerant of electrode displacement
Motoaki Miyazaki, Shinji Abe, Yoshiki Suzuki, Naoki Sakai, Takashi Ohira, Masayoshi Sugino
IEEE International Conference Microwave Intelligent Mobility   Mar 2017   
Single-Seater Vehicle Prototype Experiment Powered by High Frequency Electric Field on an Asphalt-Paved Roadway
Naoki Sakai, Daiki Itokazu, Yoshiki Suzuki, Sonshu Sakihara, Takashi Ohira
Dec 2016   
The simplest rectifier topology tolerant of load resistance variation and circuit analysis by square-wave approximation
K. Yamada, Y. Miyazaki, S. Abe, N. Sakai and T. Ohira
2016 IEEE Region 10 Conf   Nov 2016   
Yoshiki Suzuki, Minoru Mizutani, Takamitsu Sugiura, Naoki Sakai, Takashi Ohira
Electrical Engineering in Japan (English translation of Denki Gakkai Ronbunshi)   1 Apr 2016   
© 2015 Wiley Periodicals, Inc.SUMMARY Electric vehicles (EVs) are expected to play a leading role in the changeover from fossil fuels to clean energy. However, EVs are currently not very popular, owing to their short cruising distance and long cha...
Kyohei Yamada, Naoki Sakai, Takashi Ohira
2015 IEEE International Symposium on Radio-Frequency Integration Technology, RFIT 2015 - Proceedings   8 Jan 2016   
© 2015 IEEE.To design high efficiency WPT systems, we formulate the insertion loss in an L-shaped lumped-constant twoelement matching circuit in terms of the elements' quality factors and the input/output impedances which are complex impedances ra...
Sakai Naoki, Itokazu Daiki, Suzuki Yoshiki, Sakihara Sonshu, Ohira Takashi
IEEE Conference Proceedings   2016   
Impedance Matching Circuit Optimization for a Miniature EVER System from Hyperbolic Geometry
Kyohei Yamada, Naoki Sakai and Takashi Ohira
Asian Wireless Power Transfer Workshop 2015   Dec 2015   
Sakihara-Moebius Harmonometer to Measure Simultaneous Voltage and Current on Nonlinear Devices and Circuits
Masaru Tanaka, Kyohei Yamada, Naoki Sakai and Takashi Ohira
Asian Wireless Power Transfer Workshop 2015   Dec 2015   
Mathematical Model of Parallel-Plate-Pair Wireless Power Transfer Capacitive Coupling Coefficient
Shinji ABE, Naoki Sakai, and Takashi Ohira
Interdisciplinary Research and Global Outlook Conference 2015   Oct 2015   
Harmonics Measurement for Nonlinear RF Components Based on Six-Port Technique
Kyohei Yamada, Sonshu Sakihara, Naoki Sakai, and Takashi Ohira
Interdisciplinary Research and Global Outlook Conference 2015   Oct 2015   
Nonlinear Load Impedance Measurement System Exploiting Time-Domain Waveform and Mbius Transformation
Sonshu Sakihara, Masaru Tanaka, Kyohei Yamada, Naoki Sakai, and Takashi Ohira
Interdisciplinary Research and Global Outlook Conference 2015   Oct 2015   
Power Loss Formula for Impedance Matching Circuits Dedicated to Wireless Power Transfer
K. Yamada, S. Naoki, and T. Ohira
2015 IEEE International Symposium on Radio-Frequency Integration Technology   Aug 2015   
Power Transfer k-Q Product Explored for a Variety of Two-port LCR Circuit Topologies
Naoki Sakai, Takashi Ohira
Progress in Electromagnetics Research Symposium PIERS 2014   Aug 2014   
Yosuke Omori, Naoki Sakai, Takashi Ohira
8th European Conference on Antennas and Propagation, EuCAP 2014   1 Jan 2014   
© 2014 European Association on Antennas and Propagation.This paper proposes an active tapping scheme to wireless secret key generator (WSKG), and evaluates tapping tolerance of WSKG for the active tapping scheme. An active tapping scheme is a tapp...
Electric Vehicle on Electrified Roadway Maquette Demonstrator
N. Sakai, Y. Suzuki, T. Torii, Y. Kitagawa, and T. Ohira
International conference of Global Network for Innovative TEchnology 2013   Dec 2013   
Imac Enhancement Exploiting the Eigen- value of RadioWave Fluctuation in Secret Key Agreement System
T. Yoshida, Y. Omori, N. Sakai, T. Ohira
2013 Asia-Pacific Radio Science Conference (APRASC’13)   Sep 2013   
Y. Suzuki, T. Sugiura, N. Sakai, M. Hanazawa, T. Ohira
2012 IEEE MTT-S International Microwave Workshop Series on Innovative Wireless Power Transmission: Technologies, Systems, and Applications, IMWS-IWPT 2012 - Proceedings   17 Jul 2012   
This paper demonstrates the feasibility of the wireless power transfer using dielectric coupling between a steel belt in a tire and a metal plate in a roadway. The scheme is called Tire Dielectric Coupling. We designed and prototyped the feeding s...
Masahiro Hanazawa, Naoki Sakai, Takashi Ohira
2012 IEEE International Electric Vehicle Conference, IEVC 2012   15 May 2012   
This paper presents an experimental RF characterization for a proof of concept called "Electric Vehicle on Electrified Roadway (EVER)", where the energy is fed through dielectric coupling between a steel belt in a tire and a metal plate laid under...
Naoki Sakai, Hideyuki Uehara, Takashi Ohira
APMC 2009 - Asia Pacific Microwave Conference 2009   1 Dec 2009   
This paper characterizes 3-element ESPAR antenna's variable beamforming performance from a viewpoint of directivity complexity. We measure and analyze antenna about radiation directivity. The result shows that directivity pattern is numerous and w...