Search Results - "Sakamoto, Takahide"

High-Speed Control of Lightwave Amplitude, Phase, and Frequency by Use of Electrooptic Effect by Kawanishi, T., Sakamoto, T., Izutsu, M.

“…High-speed control of lightwave using electrooptic (EO) effect is investigated in this paper. Agile optical frequency shift can be achieved by optical…”
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High Speed 2-D Photodetector Array for Space and Mode-Division Multiplexing Fiber Communications by Umezawa, Toshimasa, Sakamoto, Takahide, Kanno, Atsushi, Yamamoto, Naokatsu, Kawanishi, Tetsuya

“…We report a high-data-rate two-dimensional photodetector array (2D-PDA) operated over 10 GHz for compact receiver systems in multicore fiber (MCF), few-mode…”
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Wavelength conversion of optical 64QAM through FWM in HNLF and its performance optimization by constellation monitoring by Lu, Guo-Wei, Sakamoto, Takahide, Kawanishi, Tetsuya

“…All-optical wavelength conversion (AOWC) plays an important role in the future transparent optical networks, in order to enhance the re-configurability and…”
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25-Gbaud 4-WDM Free-Space Optical Communication Using High-Speed 2-D Photodetector Array by Umezawa, Toshimasa, Sakamoto, Takahide, Kanno, Atsushi, Matsumoto, Atsushi, Akahane, Kouichi, Yamamoto, Naokatsu, Kawanishi, Tetsuya

“…We present a newly developed two-dimensional photodetector array (2D-PDA) device and its application for short-range free-space optical (FSO) communication…”
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Laser-Phase-Fluctuation-Insensitive Optical Coherent Transmission of 16-Quadrature-Amplitude-Modulation Radio-Over-Fiber Signal by Kuri, Toshiaki, Sakamoto, Takahide, Kawanishi, Tetsuya

“…A laser-phase-fluctuation-insensitive optical coherent transmission of a 10-Gbaud 16-quadrture-amplitude-modulation radio-over-fiber signal with an…”
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Coherent synthesis of optical multilevel signals by electrooptic digital-to-analog conversion using multiparallel modulator by Sakamoto, Takahide, Chiba, Akito

“…This paper presents an electrooptic vector digital-to-analog converter (EO-DAC) for coherent synthesis of optical multilevel signals, such as…”
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Flexible generation of 28 Gbps PAM4 60 GHz/80 GHz radio over fiber signal by injection locking of direct multilevel modulated laser to spacing-tunable two-tone light by Lu, Guo-Wei, Luís, Ruben S, Toda, Hiroyuki, Cui, Jiabin, Sakamoto, Takahide, Wang, Hongxiang, Ji, Yuefeng, Yamamoto, Naokatsu

“…To meet the ever-increasing bandwidth demands in the future broadband wireless networks, the millimeter-wave (mm-wave) frequency region is being actively…”
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Loop-Assisted Coherent Matched Detector for Parallel Time-Frequency Sampling by Sakamoto, Takahide, Guo-Wei Lu, Yamamoto, Naokatsu

“…Optical sampling is performed mostly in either time or frequency domain. In the former approach, sampling points are temporally taken by photo-mixing of…”
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Simultaneous multichannel wavelength multicasting and XOR logic gate multicasting for three DPSK signals based on four-wave mixing in quantum-dot semiconductor optical amplifier by Qin, Jun, Lu, Guo-Wei, Sakamoto, Takahide, Akahane, Kouichi, Yamamoto, Naokatsu, Wang, Danshi, Wang, Cheng, Wang, Hongxiang, Zhang, Min, Kawanishi, Tetsuya, Ji, Yuefeng

“…In this paper, we experimentally demonstrate simultaneous multichannel wavelength multicasting (MWM) and exclusive-OR logic gate multicasting (XOR-LGM) for…”
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Ultrashort optical pulse source using Mach–Zehnder-modulator-based flat comb generator by Morohashi, Isao, Sakamoto, Takahide, Sekine, Norihiko, Kasamatsu, Akifumi, Hosako, Iwao

“…We reported ultrashort pulse generation using a Mach–Zehnder-modulator-based flat comb generator (MZ-FCG) and a dispersion-flattened dispersion-decreasing…”
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Multi-tone parallel coherent matched detection for demultiplexing of superchannels by Sakamoto, Takahide, Lu, Guo-Wei, Kawanishi, Tetsuya

“…This paper presents multi-tone parallel coherent matched detection that orthogonally detects superchannels without crosstalk between neighboring channels. The…”
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Laser-Phase-Fluctuation-Insensitive Optical Coherent Detection Scheme for Radio-over-Fiber System by Kuri, Toshiaki, Sakamoto, Takahide, Guo-Wei Lu, Kawanishi, Tetsuya

“…Laser-phase-fluctuation-insensitive optical coherent detection scheme with two-tone local light and digital signal processing technique for a radio-over-fiber…”
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High Extinction Ratio Mach-Zehnder Modulator Applied to a Highly Stable Optical Signal Generator by Kiuchi, H., Kawanishi, T., Yamada, M., Sakamoto, T., Tsuchiya, M., Amagai, J., Izutsu, M.

“…Research into optical modulators has made remarkable progress in recent years. This paper discusses the possibility of applying the high extinction ratio…”
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Pump-linewidth-tolerant optical wavelength conversion for high-order QAM signals using coherent pumps by Lu, Guo-Wei, Albuquerque, André, Puttnam, Benjamin J, Sakamoto, Takahide, Drummond, Miguel, Nogueira, Rogério, Kanno, Atsushi, Shinada, Satoshi, Wada, Naoya, Kawanishi, Tetsuya

“…Optical wavelength conversion (OWC) is expected to be a desirable function in future optical transparent networks. Since high-order quadrature amplitude…”
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Rectangular QPSK for generation of optical eight-ary phase-shift keying by Lu, Guo-Wei, Sakamoto, Takahide, Kawanishi, Tetsuya

“…Quadrature phase-shift keying (QPSK) is usually generated using an in-phase/quadrature (IQ) modulator in a balanced driving-condition, showing a square-shape…”
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Low-Crosstalk Balanced Bridge Interferometric-Type Optical Switch for Optical Signal Routing by Chiba, Akito, Kawanishi, Tetsuya, Sakamoto, Takahide, Higuma, Kaoru, Takada, Kazumasa, Izutsu, Masayuki

“…Crosstalk is one of the significant measures of an optical cross-bar switch. In this paper, we describe a configuration for crosstalk suppression of a…”
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Evaluation of back-side flaws of the bottom plates of an oil-storage tank by the RFECT by Kasai, Naoya, Fujiwara, Yasuhiro, Sekine, Kazuyoshi, Sakamoto, Takahide

“…In the present study, the remote field eddy current testing (RFECT) was used to detect back-side local corrosion in the bottom plates of an oil storage tank…”
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Experimental and analytical study for detectability of the back-side flaws of flat ferromagnetic plates by RFECT by Kasai, Naoya, Matsuzaki, Syotaro, Sakamoto, Takahide

“…In the present study, two types of ferrite core probes were prepared with different pick-up coil positions for remote field eddy current testing. One probe has…”
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High-speed optical DQPSK and FSK modulation using integrated Mach-Zehnder interferometers by Kawanishi, Tetsuya, Sakamoto, Takahide, Miyazaki, Tetsuya, Izutsu, Masayuki, Fujita, Takahisa, Mori, Shingo, Higuma, Kaoru, Ichikawa, Junichiro

“…We investigated an integrated optical modulator consisting of two Mach-Zehnder interferometers. The modulator can generate optical signals in various types of…”
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Simple Self-Homodyne Detection Scheme for Optical OFDM With Inserted Pilot Subframes and Application in Optical Access Networks by Guo-Wei Lu, Xun Guan, Sakamoto, Takahide, Yamamoto, Naokatsu, Chan, Calvin Chun-Kit

“…In this paper, a simple self-homodyne detection scheme is proposed and experimentally demonstrated for applications in optical access networks. Unmodulated…”
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