Yoshihiro NAKA Masahiko NISHIMOTO Mitsuhiro YOKOTA
Hiroki Hoshino Kentaro Kusama Takayuki Arai
Tsuneki YAMASAKI
Kengo SUGAHARA
Cuong Manh BUI Hiroshi SHIRAI
Hiroyuki DEGUCHI Masataka OHIRA Mikio TSUJI
Hiroto Tochigi Masakazu Nakatani Ken-ichi Aoshima Mayumi Kawana Yuta Yamaguchi Kenji Machida Nobuhiko Funabashi Hideo Fujikake
Yuki Imamura Daiki Fujii Yuki Enomoto Yuichi Ueno Yosei Shibata Munehiro Kimura
Keiya IMORI Junya SEKIKAWA
Naoki KANDA Junya SEKIKAWA
Yongzhe Wei Zhongyuan Zhou Zhicheng Xue Shunyu Yao Haichun Wang
Mio TANIGUCHI Akito IGUCHI Yasuhide TSUJI
Kouji SHIBATA Masaki KOBAYASHI
Zhi Earn TAN Kenjiro MATSUMOTO Masaya TAKAGI Hiromasa SAEKI Masaya TAMURA
Misato ONISHI Kazuhiro YAMAGUCHI Yuji SAKAMOTO
Koya TANIKAWA Shun FUJII Soma KOGURE Shuya TANAKA Shun TASAKA Koshiro WADA Satoki KAWANISHI Takasumi TANABE
Shotaro SUGITANI Ryuichi NAKAJIMA Keita YOSHIDA Jun FURUTA Kazutoshi KOBAYASHI
Ryosuke Ichikawa Takumi Watanabe Hiroki Takatsuka Shiro Suyama Hirotsugu Yamamoto
Toshio MURAYAMA Amane TAKEI
Chan-Liang Wu Chih-Wen Lu
Umer FAROOQ Masayuki MORI Koichi MAEZAWA
Ryo ITO Sumio SUGISAKI Toshiyuki KAWAHARAMURA Tokiyoshi MATSUDA Hidenori KAWANISHI Mutsumi KIMURA
Paul Cain
Arie SETIAWAN Shu SATO Naruto YONEMOTO Hitoshi NOHMI Hiroshi MURATA
Seiichiro Izawa
Hang Liu Fei Wu
Keiji GOTO Toru KAWANO Ryohei NAKAMURA
Takahiro SASAKI Yukihiro KAMIYA
Xiang XIONG Wen LI Xiaohua TAN Yusheng HU
Tohgo HOSODA Kazuyuki SAITO
Shohei Matsuhara Kazuyuki Saito Tomoyuki Tajima Aditya Rakhmadi Yoshiki Watanabe Nobuyoshi Takeshita
Yihan ZHU Takashi OHSAWA
Shengbao YU Fanze MENG Yihan SHEN Yuzhu HAO Haigen ZHOU
Ryo KUMAGAI Ryosuke SUGA Tomoki UWANO
Jun SONODA Kazusa NAKAMICHI
Kaiji Owaki Yusuke Kanda Hideaki Kimura
Fan Liu Zhewang Ma Masataka Ohira Dongchun Qiao Guosheng Pu Masaru Ichikawa
Hyunuk AHN Akito IGUCHI Keita MORIMOTO Yasuhide TSUJI
Kensei ITAYA Ryosuke OZAKI Tsuneki YAMASAKI
Akira KAWAHARA Jun SHIBAYAMA Kazuhiro FUJITA Junji YAMAUCHI Hisamatsu NAKANO
Seiya Kishimoto Ryoya Ogino Kenta Arase Shinichiro Ohnuki
Yasuo OHTERA
Haonan CHEN Akito IGUCHI Yasuhide TSUJI
An interpretation method of inversion phenomena is newly proposed for backward transient scattered field components for both E- and H-polarizations when an ultra-wideband (UWB) pulse wave radiated from a line source is incident on a two-dimensional metal cylinder covered with a lossless dielectric medium layer (coated metal cylinder). A time-domain (TD) asymptotic solution, which is referred to as a TD saddle point technique (TD-SPT), is derived by applying the SPT in evaluating a backward transient scattered field which is expressed by an integral form. The TD-SPT is represented by a combination of a direct geometric optical ray (DGO) and a reflected GO (RGO) series, thereby being able to extract and calculate any backward transient scattered field component from a response waveform. The TD-SPT is useful in understanding the response waveform of a backward transient scattered field by a coated metal cylinder because it can give us the peak value and arrival time of any field component, namely DGO and RGO components, and interpret analytically inversion phenomenon of any field component. The accuracy, validity, and practicality of the TD-SPT are clarified by comparing it with two kinds of reference solutions.
Marimo MATSUMOTO Masaya TAMURA
Couplers in a film-type capacitive wireless power charging (CWC) system for an implantable medical device were designed and analyzed in this work. Due to the high conductivity of the human body, two paths contribute to the power transmission, namely a high-frequency current and an electric field. This was confirmed by an equivalent circuit of the system. During analysis of the system, we used pig skin with subcutaneous fat, which has a high affinity with the human body, to search for a highly efficient electrode shape. Subsequently, we fabricated the designed coupler and measured ηmax. An ηmax of 56.6% was obtained for a half-circular coupler with a radius of 20 mm and a distance of 10 mm between adjacent couplers. This study will contribute to the realization of implantable devices that can be recharged during breaks or while sleeping at home and is expected to significantly reduce the burden on patients.
Aoi OYANE Thilak SENANAYAKE Mitsuru MASUDA Jun IMAOKA Masayoshi YAMAMOTO
This paper proposes a topology of high power, MHz-frequency, half-bridge resonant inverter ideal for low-loss Gallium Nitride high electron mobility transistor (GaN-HEMT). General GaN-HEMTs have drawback of low drain-source breakdown voltage. This property has prevented conventional high-frequency series resonant inverters from delivering high power to high resistance loads such as 50Ω, which is typically used in radio frequency (RF) systems. High resistance load causes hard-switching also and reduction of power efficiency. The proposed topology overcomes these difficulties by utilizing a proposed ‘L-S network’. This network is effective combination of a simple impedance converter and a series resonator. The proposed topology provides not only high power for high resistance load but also arbitrary design of output wattage depending on impedance conversion design. In addition, the current through the series resonator is low in the L-S network. Hence, this series resonator can be designed specifically for harmonic suppression with relatively high quality-factor and zero reactance. Low-distortion sinusoidal 3kW output is verified in the proposed inverter at 13.56MHz by computer simulations. Further, 99.4% high efficiency is achieved in the power circuit in 471W experimental prototype.