Isao OHTA


Fabrication of Integrated PTFE-Filled Waveguide Butler Matrix for Short Millimeter-Wave by SR Direct Etching
Mitsuyoshi KISHIHARA Masaya TAKEUCHI Akinobu YAMAGUCHI Yuichi UTSUMI Isao OHTA 
Publication:   
Publication Date: 2018/06/01
Vol. E101-C  No. 6  pp. 416-422
Type of Manuscript:  PAPER
Category: Microwaves, Millimeter-Waves
Keyword: 
microstructureX-ray lithographydielectric loaded waveguidesButler matrixmillimeter wave circuits
 Summary | Full Text:PDF(1.2MB)

Left-Handed Waveguide Using Cutoff TM-Mode
Mitsuyoshi KISHIHARA Yuki MIZUTANI Isao OHTA Kensuke OKUBO Hironori TAKIMOTO 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2016/01/01
Vol. E99-C  No. 1  pp. 61-67
Type of Manuscript:  Special Section PAPER (Special Section on Recent Progress in Electromagnetic Theory and Its Application)
Category: 
Keyword: 
circular waveguidesEBG deviceselectromagnetic propagationrectangular waveguides
 Summary | Full Text:PDF(930.5KB)

Parallel Ring-Line Rat-Race Circuit with Very Loose Coupling Utilizing Composite Right-/Left-Handed Transmission Lines
Tadashi KAWAI Yuma SUMITOMO Akira ENOKIHARA Isao OHTA Kei SATOH Yasunori SUZUKI Hiroshi OKAZAKI Shoichi NARAHASHI 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2014/10/01
Vol. E97-C  No. 10  pp. 965-971
Type of Manuscript:  Special Section PAPER (Special Section on Recent Progress in Microwave and Millimeter-wave Technologies)
Category: 
Keyword: 
microwave passive componentsrat-race circuitloose couplingCRLH-TLwideband
 Summary | Full Text:PDF(2.1MB)

Design and Fabrication of PTFE-Filled Waveguide Components by SR Direct Etching
Mitsuyoshi KISHIHARA Hiroaki IKEUCHI Yuichi UTSUMI Tadashi KAWAI Isao OHTA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2012/01/01
Vol. E95-C  No. 1  pp. 122-129
Type of Manuscript:  PAPER
Category: Microwaves, Millimeter-Waves
Keyword: 
X-ray lithographybandpass filtersdirectional couplerssputteringdielectric materials
 Summary | Full Text:PDF(2.3MB)

Design of an H-Plane Waveguide Intersection with High Isolation
Hiroaki IKEUCHI Tadashi KAWAI Mitsuyoshi KISHIHARA Isao OHTA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2011/10/01
Vol. E94-C  No. 10  pp. 1572-1578
Type of Manuscript:  Special Section PAPER (Special Section on Microwave and Millimeter-Wave Technology)
Category: Passive Devices and Circuits
Keyword: 
microwavewaveguide circuitwaveguide intersectioncrossoverSIW
 Summary | Full Text:PDF(1.1MB)

Design of a Broadband Cruciform Substrate Integrated Waveguide Coupler
Mitsuyoshi KISHIHARA Isao OHTA Kensuke OKUBO 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2011/02/01
Vol. E94-C  No. 2  pp. 248-250
Type of Manuscript:  LETTER
Category: Microwaves, Millimeter-Waves
Keyword: 
millimeter-wave technologypassive componentscouplerssubstrate-integrated waveguide (SIW)planar circuit approach
 Summary | Full Text:PDF(246.4KB)

Band-Broadening Design Technique of CRLH-TLs Dual-Band Branch-Line Couplers Using CRLH-TLs Matching Networks
Tadashi KAWAI Miku NAKAMURA Isao OHTA Akira ENOKIHARA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2010/07/01
Vol. E93-C  No. 7  pp. 1072-1077
Type of Manuscript:  Special Section PAPER (Special Section on Recent Progress in Microwave and Millimeter-Wave Technologies)
Category: 
Keyword: 
branch-line couplermatching networkCRLH-TLdual-bandequivalent admittance approachsize reduction
 Summary | Full Text:PDF(2MB)

Shielded Structure of Composite Right/Left-Handed Transmission Line Using Substrate Integrated Waveguide and Floating-Conductor
Kensuke OKUBO Mitsuyoshi KISHIHARA Akifumi IKEDA Jiro YAMAKITA Isao OHTA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2010/07/01
Vol. E93-C  No. 7  pp. 1055-1062
Type of Manuscript:  Special Section PAPER (Special Section on Recent Progress in Microwave and Millimeter-Wave Technologies)
Category: 
Keyword: 
composite right/left-handed transmission line (CRLH-TL)substrate integrated waveguide (SIW)SIW-type CRLHfloating-conductorshielded structureperiodic structure
 Summary | Full Text:PDF(2.1MB)

Analysis of Post-Wall Waveguide Based on H-Plane Planar Circuit Approach
Mitsuyoshi KISHIHARA Isao OHTA Kensuke OKUBO Jiro YAMAKITA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2009/01/01
Vol. E92-C  No. 1  pp. 63-71
Type of Manuscript:  Special Section PAPER (Special Section on Recent Progress in Electromagnetic Theory and its Application)
Category: 
Keyword: 
parallel-plate waveguidessubstrate integrated waveguide (SIW)waveguide discontinuitiespassive circuits
 Summary | Full Text:PDF(829KB)

Dual-Band Wilkinson Power Dividers Using a Series RLC Circuit
Tadashi KAWAI Yasuaki NAKASHIMA Yoshihiro KOKUBO Isao OHTA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2008/11/01
Vol. E91-C  No. 11  pp. 1793-1797
Type of Manuscript:  Special Section PAPER (Special Section on Microwave and Millimeter-wave Technologies)
Category: 
Keyword: 
microwave passive componentsdual-bandpower dividerWilkinson power divider
 Summary | Full Text:PDF(526KB)

Parallel Coupled Microstrip Couplers Compensated with Periodic Floating-Conductors on Coupled Edges
Takao FUJII Isao OHTA Tadashi KAWAI Yoshihiro KOKUBO 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2008/05/01
Vol. E91-C  No. 5  pp. 780-787
Type of Manuscript:  PAPER
Category: Microwaves, Millimeter-Waves
Keyword: 
artificial coupled-linedirectional couplersmicrostrip couplersparallel coupled linesperiodically loading
 Summary | Full Text:PDF(1.8MB)

Miniature Broad-Band CPW 3-dB Branch-Line Couplers in Slow-Wave Structure
Takao FUJII Isao OHTA Tadashi KAWAI Yoshihiro KOKUBO 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2007/12/01
Vol. E90-C  No. 12  pp. 2245-2253
Type of Manuscript:  Special Section PAPER (Special Section on Recent Technologies for Microwave and Millimeter-wave Passive Devices)
Category: 
Keyword: 
coplanar waveguidesdirectional couplershybridsequivalent admittancemicrowave circuitsslow-wave structure
 Summary | Full Text:PDF(1.7MB)

Cruciform Directional Couplers in E-Plane Rectangular Waveguide
Mitsuyoshi KISHIHARA Isao OHTA Kuniyoshi YAMANE 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2007/09/01
Vol. E90-C  No. 9  pp. 1743-1748
Type of Manuscript:  Special Section PAPER (Special Section on Microwave and Millimeter-Wave Technology)
Category: Passive Devices/Circuits
Keyword: 
microwave devicesdirectional couplersrectangular waveguidesdesign automationgenetic algorithms
 Summary | Full Text:PDF(658KB)

Multi-Stage, Multi-Way Microstrip Power Dividers with Broadband Properties
Mitsuyoshi KISHIHARA Isao OHTA Kuniyoshi YAMANE 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2006/05/01
Vol. E89-C  No. 5  pp. 622-629
Type of Manuscript:  PAPER
Category: Microwaves, Millimeter-Waves
Keyword: 
design automationmicrostrip componentsmultiport circuitspower dividersChebyshev transformers
 Summary | Full Text:PDF(683.5KB)

Broadband Multi-Way Microstrip Power Dividers
Mitsuyoshi KISHIHARA Kuniyoshi YAMANE Isao OHTA Tadashi KAWAI 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2005/01/01
Vol. E88-C  No. 1  pp. 20-27
Type of Manuscript:  Special Section PAPER (Special Section on Recent Trends of Microwave and Millimeter-Wave Passive Circuit Components and Technologies for Improvement of Characteristics)
Category: 
Keyword: 
power dividersmicrostrip componentsmultiport circuitsChebyshev transformersdesign automation
 Summary | Full Text:PDF(1.3MB)

Design of Quadrature Hybrids and Directional Couplers Based on the Equivalent Admittance Approach
Isao OHTA Tadashi KAWAI 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2005/01/01
Vol. E88-C  No. 1  pp. 2-14
Type of Manuscript:  INVITED PAPER (Special Section on Recent Trends of Microwave and Millimeter-Wave Passive Circuit Components and Technologies for Improvement of Characteristics)
Category: 
Keyword: 
microwave passive componentdirectional couplerhybridmicrowave integrated circuitequivalent admittance approach
 Summary | Full Text:PDF(2.3MB)

Asymmetrical Coupled-HNRD-Guide Directional Couplers with Flat Coupling
Mitsuyoshi KISHIHARA Isao OHTA Tadashi KAWAI Kuniyoshi YAMANE 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2003/02/01
Vol. E86-C  No. 2  pp. 126-133
Type of Manuscript:  Special Section PAPER (Special Issue on Circuit and Device Technology for High-Speed Wireless Communication)
Category: Passive (Coupler)
Keyword: 
NRD guidetransverse resonance techniquedirectional couplermillimeter wavecoupled-line
 Summary | Full Text:PDF(898.2KB)

A New Wide-Band and Reduced-Size Hybrid Ring
Tadashi KAWAI Isao OHTA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2003/02/01
Vol. E86-C  No. 2  pp. 134-138
Type of Manuscript:  Special Section PAPER (Special Issue on Circuit and Device Technology for High-Speed Wireless Communication)
Category: Passive (Coupler)
Keyword: 
hybrid ringequivalent admittanceuniplanar circuitphase inverterbroadband
 Summary | Full Text:PDF(300.4KB)

Analysis and Design of Integrated Structures of (H)NRD Guide and E-Plane Waveguide Based on Transverse Resonance Technique
Mitsuyoshi KISHIHARA Isao OHTA Kuniyoshi YAMANE 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2001/10/01
Vol. E84-C  No. 10  pp. 1561-1568
Type of Manuscript:  Special Section PAPER (Special Issue on Millimeter-Wave Circuits and Fabrication Technologies Opening up the 21st Century)
Category: 
Keyword: 
NRD guidetransverse resonance techniquetransitiondirectional couplermillimeter wave
 Summary | Full Text:PDF(501.3KB)

A Novel 180-Degree 3 dB Hybrid Using a Cylindrical Cavity
Mitsuyoshi KISHIHARA Tadashi KAWAI Yoshihiro KOKUBO Isao OHTA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 1999/07/25
Vol. E82-C  No. 7  pp. 1148-1153
Type of Manuscript:  Special Section PAPER (Special Issue on Microwave and Millimeter Wave Technology)
Category: Passive Devices and Circuits
Keyword: 
waveguidewaveguide componentE-plane planar circuithybrid
 Summary | Full Text:PDF(1.1MB)

A Power-Combining system of Four Oscillators Using an Eight-Port Hybrid
Isao OHTA Tadashi KAWAI Yoshihiro KOKUBO 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 1996/10/25
Vol. E79-C  No. 10  pp. 1449-1454
Type of Manuscript:  PAPER
Category: Microwave and Millimeter Wave Technology
Keyword: 
microwavemicrowave oscillatorpower combiningparallel runningmutual synchronization
 Summary | Full Text:PDF(489.4KB)

A Rat-Race-Type Directional Coupler for Loose Coupling
Isao OHTA Hiroshi TANIGUCHI Takenori KANEKO 
Publication:   IEICE TRANSACTIONS (1976-1990)
Publication Date: 1988/04/25
Vol. E71-E  No. 4  pp. 304-306
Type of Manuscript:  Special Section LETTER (Special Issue: Papers from 1988 Spring Convention IEICE)
Category: Electromagnetic Theory and Microwave Circuits
Keyword: 
 Summary | Full Text:PDF(175.9KB)

Optimum Ports Arrangement for a Planar-Circuit-Type 3 dB Hybrid
Isao OHTA Toshiyuki YAMASHITA Ichiro HAGINO 
Publication:   IEICE TRANSACTIONS (1976-1990)
Publication Date: 1984/05/25
Vol. E67-E  No. 5  pp. 287-288
Type of Manuscript:  LETTER
Category: Microwaves and Millimeter Waves
Keyword: 
 Summary | Full Text:PDF(187.2KB)

Noise Analysis of Mutually but Asymmetrically Synchronized Oscillators
Isao OHTA Kiyoshi FUKUI 
Publication:   IEICE TRANSACTIONS (1976-1990)
Publication Date: 1976/04/25
Vol. E59-E  No. 4  pp. 9-10
Type of Manuscript:  LETTER
Category: Circuits and Systems
Keyword: 
 Summary | Full Text:PDF(164.9KB)