Yahei KOYAMADA


Phase Control and Calibration Characteristics of Optically Controlled Phased Array Antenna Feed Using Multiple SMFs
Daiki TAKEUCHI Wataru CHUJO Shin-ichi YAMAMOTO Yahei KOYAMADA 
Publication:   IEICE TRANSACTIONS on Electronics
Publication Date: 2011/10/01
Vol. E94-C  No. 10  pp. 1634-1640
Type of Manuscript:  Special Section PAPER (Special Section on Microwave and Millimeter-Wave Technology)
Category: Microwave and Millimeter-Wave Antennas
Keyword: 
optically controlled phased array antennaSMFLDmicrowavemillimeter-wavecalibration
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Restorability of Rayleigh Backscatter Traces Measured by Coherent OTDR with Precisely Frequency-Controlled Light Source
Mutsumi IMAHAMA Yahei KOYAMADA Kazuo HOGARI 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2008/04/01
Vol. E91-B  No. 4  pp. 1243-1246
Type of Manuscript:  LETTER
Category: Sensing
Keyword: 
Rayleigh scatteringcoherent OTDRfiber sensorstrain measurementtemperature measurement
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Proposal and Simulation of Double-Pulse Brillouin Optical Time-Domain Analysis for Measuring Distributed Strain and Temperature with cm Spatial Resolution in km-Long Fiber
Yahei KOYAMADA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2007/07/01
Vol. E90-B  No. 7  pp. 1810-1815
Type of Manuscript:  PAPER
Category: Sensing
Keyword: 
fiber sensorBrillouin scatteringdistributed measurementstrain measurementtemperature measurement
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Novel Fiber-Optic Distributed Strain and Temperature Sensor with Very High Resolution
Yahei KOYAMADA Yousuke EDA Souichi HIROSE Shinki NAKAMURA Kazuo HOGARI 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2006/05/01
Vol. E89-B  No. 5  pp. 1722-1725
Type of Manuscript:  LETTER
Category: Sensing
Keyword: 
fiber-optic sensordistributed sensorstrain sensortemperature sensorOTDR
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Brillouin Optical-Fiber Time Domain Reflectometry
Toshio KURASHIMA Tsuneo HORIGUCHI Hisashi IZUMITA Shin-ichi FURUKAWA Yahei KOYAMADA 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 1993/04/25
Vol. E76-B  No. 4  pp. 382-390
Type of Manuscript:  Special Section PAPER (Special Issue on Optical Fiber Cables and Related Technologies)
Category: 
Keyword: 
Brillouin scatteringoptical fiberstraincoherent detectiontemerature
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Optical Fiber Line Surveillance System for Preventive Maintenance Based on Fiber Strain and Loss Monitoring
Izumi SANKAWA Yahei KOYAMADA Shin-ichi FURUKAWA Tsuneo HORIGUCHI Nobuo TOMITA Yutaka WAKUI 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 1993/04/25
Vol. E76-B  No. 4  pp. 402-409
Type of Manuscript:  Special Section PAPER (Special Issue on Optical Fiber Cables and Related Technologies)
Category: 
Keyword: 
optical fiberconnectorsurveillance systempreventive maintenanceoptical time domain reflectometry
 Summary | Full Text:PDF