Hiroaki SEKI

Design and Measurements of Two-Gain-Mode GaAs-BiFET MMIC Power Amplifier Modules with Small Phase Discontinuity for WCDMA Data Communications
Kazuya YAMAMOTO Miyo MIYASHITA Kenji MUKAI Shigeru FUJIWARA Satoshi SUZUKI Hiroaki SEKI 
Publication:   
Publication Date: 2018/01/01
Vol. E101-C  No. 1  pp. 65-77
Type of Manuscript:  PAPER
Category: Microwaves, Millimeter-Waves
Keyword: 
WCDMA, MMIC, step attenuator, two gain modes, directional coupler, heterojunction bipolar transistors (HBTs), 
 Summary | Full Text:PDF
Experimental Study on CDMA GaAs HBT MMIC Power Amplifier Layout Design for Reducing Turn-On Delay in Transient Response
Kazuya YAMAMOTO Miyo MIYASHITA Takayuki MATSUZUKA Tomoyuki ASADA Kazunobu FUJII Satoshi SUZUKI Teruyuki SHIMURA Hiroaki SEKI 
Publication:   
Publication Date: 2017/06/01
Vol. E100-C  No. 6  pp. 618-631
Type of Manuscript:  PAPER
Category: Microwaves, Millimeter-Waves
Keyword: 
heterojunction bipolar transistors (HBTs), MMIC, CDMA, parallel-amplifier-chain topology, transient response, thermal coupling, 
 Summary | Full Text:PDF
Design and Measurements of Building Blocks Supporting a 1.9-GHz-Band BiFET MMIC Power Amplifier for WCDMA Handsets
Kazuya YAMAMOTO Takayuki MATSUZUKA Miyo MIYASHITA Kenichi HORIGUCHI Shigeo YAMABE Satoshi SUZUKI Hiroaki SEKI 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2016/07/01
Vol. E99-C  No. 7  pp. 837-848
Type of Manuscript:  PAPER
Category: Microwaves, Millimeter-Waves
Keyword: 
MMIC, reference voltage generator, ESD protection, three power modes, heterojunction bipolar transistors (HBTs), WCDMA, 
 Summary | Full Text:PDF
A Current-Mirror-Based GaAs-HBT RF Power Detector Suitable for Base Terminal Monitoring in an HBT Power Stage
Kazuya YAMAMOTO Hitoshi KURUSU Miyo MIYASHTA Satoshi SUZUKI Hiroaki SEKI 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2015/12/01
Vol. E98-C  No. 12  pp. 1150-1160
Type of Manuscript:  PAPER
Category: Microwaves, Millimeter-Waves
Keyword: 
power detector, current-mirror circuits, heterojunction bipolar transistors (HBTs), WiMAX, MMIC, 
 Summary | Full Text:PDF
0.8-/1.5-GHz-Band WCDMA HBT MMIC Power Amplifiers with an Analog Bias Control Scheme
Kazuya YAMAMOTO Takayuki MATSUZUKA Miyo MIYASHITA Kenichi MAEDA Satoshi SUZUKI Hiroaki SEKI 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2015/09/01
Vol. E98-C  No. 9  pp. 934-945
Type of Manuscript:  PAPER
Category: Microwaves, Millimeter-Waves
Keyword: 
analog bias control, emitter follower, current injection, heterojunction bipolar transistors (HBTs), WCDMA, 
 Summary | Full Text:PDF
A 3.5-GHz-Band GaAs HBT Stage-Bypass-Type Step-Gain Amplifier Using Base-Collector Diode Switches and Its Application to a WiMAX HBT MMIC Power Amplifier Module
Kazuya YAMAMOTO Miyo MIYASHITA Hitoshi KURUSU Yoshinobu SASAKI Satoshi SUZUKI Hiroaki SEKI 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2015/07/01
Vol. E98-C  No. 7  pp. 716-728
Type of Manuscript:  PAPER
Category: Microwaves, Millimeter-Waves
Keyword: 
step gain control, diode switches, heterojunction bipolar transistors (HBTs), WiMAX, MMIC, 
 Summary | Full Text:PDF
A Low Quiescent Current CV/CC Parallel Operation HBT Power Amplifier for W-CDMA Terminals
Shintaro SHINJO Kazutomi MORI Hiro-omi UEDA Akira OHTA Hiroaki SEKI Noriharu SUEMATSU Tadashi TAKAGI 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2003/08/01
Vol. E86-C  No. 8  pp. 1444-1450
Type of Manuscript:  Special Section PAPER (Special Issue on Microwave and Millimeter Wave Technology)
Category: 
Keyword: 
microwave, power amplifier, heterojunction bipolar transistor (HBT), inductor base feed, resistor base feed, 
 Summary | Full Text:PDF