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Publication
Featured researches published by Hisao Yoshinaga.
IEEE Journal on Selected Areas in Communications | 1996
Koji Kikushima; Hisao Yoshinaga; Hiroshi Nakamoto; Chisei Kishimoto; Masami Kawabe; Ko-ichi Suto; Kiyomi Kumozaki; Nori Shibata
A novel super wideband optical FM modulation scheme that employs an optical heterodyne detection technique is proposed and demonstrated. The experimental results show that applying this scheme to 40-channel AM video transmission expands the power budget by approximately 10 dB at a carrier- to-noise ratio (CNR) of 42 dB. The feasibility of the scheme is also discussed from the viewpoints of connector reflectivity and fiber-dispersion.
IEEE Photonics Technology Letters | 1996
Koji Kikushima; Ko-ichi Suto; H. Nakamoto; Hisao Yoshinaga; Chisei Kishimoto; M. Kawabe; Kiyomi Kumozaki; Nori Shibata
A novel super-wide-band optical FM modulation scheme employing an optical heterodyne detection technique is proposed and demonstrated. Experimental results show that by applying this scheme to 40-channel AM video transmission, the power budget is expanded by approximately 10 dB at a CNR of 42 dB.
european conference on optical communication | 2006
Satoshi Ikeda; Hisao Yoshinaga; Tomoki Sugawa
In Japan, as FTTH network service has become popular, many video distribution services are being started. In this paper, we introduce recent FTTH deployment and systems focusing on the video services of NTT in Japan.
international conference on transparent optical networks | 2006
Koji Kikushima; Hisao Yoshinaga; Shinichi Aoyagi
This paper outlines the FTTH systems being out to commercial use by NTT. In addition, this paper also describes the technical point of Raman crosstalk that was paid attention to by the authors for the system integration
IEEE Photonics Technology Letters | 1996
Koji Kikushima; Chisei Kishimoto; Satoshi Ikeda; Hisao Yoshinaga; Kiyomi Kumozaki; Hiroyasu Mawatari; Nori Shibata
Nonrepeated 150-km transmission of 60-channel AM-video has been successfully demonstrated for the first time by employing an optical heterodyne detection type of AM/FM convertor.
Optical Amplifiers and Their Applications (1993), paper SUE5 | 1993
Koji Kikushima; Hisao Yoshinaga
Reports to date indicate that the composite second-order (CSO) distortion experienced in AM-SCM optical analog video transmission systems is caused by the coupling of the gain tilt of the EDFA with laser chirp [1,2]. Reference 3 indicated that the measured loss tilt value of the detuned optical bandpass filter that offset the gain tilt distortion was larger than the gain tilt.
lasers and electro optics society meeting | 2008
Hisao Yoshinaga; Nori Shibata
A commercial video distribution system established on the FTTH network in Japan is described. The key to commercial deployment is FM conversion of multichannel FDM video signals by means of an optical heterodyne technique.
asia pacific symposium on information and telecommunication technologies | 2015
Tomohiro Taniguchi; Toshihito Fujiwara; Hidekazu Shimizu; Ryota Shiina; Toshiaki Shitaba; Yasunobu Kasahara; Hisao Yoshinaga; Tomoki Sugawa
This paper describes the concept of the digital baseband signal broadcasting of ultra-high definition (UHD) video over an analog/digital hybrid network. It also provides, as an exemplary feasibility study, system designs for WDM (Wavelength Division Multiplexing) overlay of 10 Gbps digital baseband signal on an analog optical network based on frequency modulation conversion.
Optical Amplifiers and Their Applications (1994), paper FD1 | 1994
Koji Kikushima; Etsugo Yoneda; Hisao Yoshinaga; Ko-ichi Suto
The application of optical amplifiers to access networks is expected to have the greatest impact on optical video distribution systems. Among optical amplifiers, EDFAs are being commercially used in video trunk line systems because of their advanced maturity. This paper surveys the applications of optical amplifiers. For optical video systems that utilize optical amplifiers, we review their technical problems and countermeasures.
Proceedings of the Society Conference of IEICE | 2015
Hidekazu Shimizu; Toshihito Fujiwara; Toshiaki Shitaba; Hisao Yoshinaga; Tomoki Sugawa
