Hitachi, Ltd.

Yoshihiro Yano

Yoshihiro Ashi

Yukio Nakano

Hiroyuki Nakano

Satoshi Aoki

Tohru Kazawa

Shinya Sasaki

Masahiro Takatori

Hideaki Tsushima

Shin Nishimura

Naohiro Sakakida

Hironari Matsuda

Tadahiro Yamaguchi

Youichi Igarashi

Hiroaki Nakashima

Hiroshi Kuwaki

Osamu Matsubara

Ryoji Tateyari

Kenji Tomooka

Optical transmission equipment

An optical repeater for realizing transmission of supervisory information of an optical fiber transmission system without the output power of an optical fiber amplifier being reduced, wherein a supervisory optical transmitter and optical receiver with a wavelength which is similar to the wavelength of the pumping light source of the optical fiber amplifier are mounted, and on the input side of the optical repeater, pumping light is multiplexed in the forward direction and a supervisory optical signal, which is multiplexed in wavelength and transmitted, is demultiplexed simultaneously by the first wavelength multi- and demultiplexer and they are received by the supervisory optical receiver, and on the output side of the optical repeater, pumping light is muitiplexed in the reverse direction and a supervisory optical signal outputted from the supervisory optical transmitter is multiplexed by the second wavelength multi- and demultiplexer.

Optical fiber transmission system and supervision method of the same

Growing community of inventors

Yokohama, Japan

Yoshihiro Yano