Keiichi YAMAGUCHI


A Proposal for Adopting the Frequency Response of an Envelope Amplifier with Memoryless DPD EER PA Model
Takayuki KATO Yoshinori KOGAMI Yuuki FUNAHASHI Atsushi YAMAOKA Keiichi YAMAGUCHI Yasuhiko TANABE Jiafeng ZHOU Kevin MORRIS Gavin T. WATKINS 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2012/07/01
Vol. E95-C  No. 7  pp. 1163-1171
Type of Manuscript:  Special Section PAPER (Special Section on Recent Trends of Microwave Systems and Their Fundamental Technologies)
Category: 
Keyword: 
EERpower amplifiermemoryless DPDenvelope amplifierfrequency response
 Summary | Full Text:PDF(2.1MB)

An HPSK/OFDM 64-QAM Dual-Mode Doherty Power Amplifier Module for Mobile Terminals
Takayuki KATO Keiichi YAMAGUCHI Yasuhiko KURIYAMA Hiroshi YOSHIDA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2007/09/01
Vol. E90-C  No. 9  pp. 1678-1684
Type of Manuscript:  Special Section PAPER (Special Section on Microwave and Millimeter-Wave Technology)
Category: Active Devices/Circuits
Keyword: 
Doherty amplifierPA moduleHPSKOFDM 64-QAMmulti-modemobile terminalGaAs MMIC
 Summary | Full Text:PDF(1.8MB)

A 4-mm-Square Miniaturized Doherty Power Amplifier Module for W-CDMA Mobile Terminals
Takayuki KATO Keiichi YAMAGUCHI Yasuhiko KURIYAMA Hiroshi YOSHIDA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2007/02/01
Vol. E90-A  No. 2  pp. 310-316
Type of Manuscript:  Special Section PAPER (Special Section on Analog Circuit Techniques and Related Topics)
Category: 
Keyword: 
Doherty amplifierPA moduleW-CDMAmobile terminalGaAs MMIC
 Summary | Full Text:PDF(1.2MB)

Millimeter-Wave Monolithic GaAs HEMT Medium-Power Amplifier Having Low-Loss, CRC High-Pass Equalizer Circuits
Naoko ONO Ken ONODERA Kazuhiro ARAI Keiichi YAMAGUCHI Hiroyuki YOSHINAGA Yuji ISEKI 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2004/05/01
Vol. E87-C  No. 5  pp. 733-741
Type of Manuscript:  Special Section PAPER (Special Section on Advances in Characterization and Measurement Technologies for Microwave and Millimeter-Wave Materials, Devices and Circuits)
Category: Active Devices and Circuits
Keyword: 
K-banddriver amplifierfilter circuitHEMT
 Summary | Full Text:PDF(2.4MB)

V-Band HEMT MMICs Using BCB Thin-Film Layers on GaAs Substrates
Naoko ONO Keiichi YAMAGUCHI Minoru AMANO Masayuki SUGIURA Yuji ISEKI Eiji TAKAGI 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2001/10/01
Vol. E84-C  No. 10  pp. 1528-1534
Type of Manuscript:  Special Section PAPER (Special Issue on Millimeter-Wave Circuits and Fabrication Technologies Opening up the 21st Century)
Category: 
Keyword: 
BCBthin-film layerV-bandHEMTMMIC
 Summary | Full Text:PDF(801.2KB)

An Optimum Bias Point Study of Low Local Oscillator Power Operation for 60 GHz Drain Mixer
Keiichi YAMAGUCHI Yasuhiko KURIYAMA Eiji TAKAGI Mitsuo KONNO 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 1999/11/25
Vol. E82-C  No. 11  pp. 1982-1991
Type of Manuscript:  Special Section PAPER (Special Issue on High-Frequency/High-Speed Devices for Information and Communication Systems in the 21st Century)
Category: Low Power-Consumption RF ICs
Keyword: 
drain mixerLO powerbiasMMICmillimeter wave
 Summary | Full Text:PDF(1MB)

I-V Characteristic of YBCO Step-Edge Josephson Junction
Keiichi YAMAGUCHI Shuichi YOSHIKAWA Tsuyoshi TAKENAKA Syuichi FUJINO Kunihiko HAYASHI Tsutomu MITSUZUKA Katsumi SUZUKI Youichi ENOMOTO 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 1994/08/25
Vol. E77-C  No. 8  pp. 1218-1223
Type of Manuscript:  Special Section PAPER (Special Section on Superconducting Devices)
Category: HTS
Keyword: 
Josephson junctionhigh Tc superconductorI-V characteristicsdevice application
 Summary | Full Text:PDF(667.2KB)