Seiji Okamoto
Tohoku University
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Seiji Okamoto.
IEEE Photonics Technology Letters | 2010
Masataka Nakazawa; Seiji Okamoto; Tatsunori Omiya; Keisuke Kasai; Masato Yoshida
We report a polarization-multiplexed (Pol-Mux) 4-Gsymbol/s 256 quadrature amplitude modulation (QAM) coherent optical transmission over 160 km. A 64-Gb/s data signal was successfully transmitted with an optical bandwidth of 5.4 GHz. We also describe a Pol-Mux, 10-Gsymbol/s, 128- and 64-QAM (140 and 120 Gb/s) transmission over 150 km.
european conference on optical communication | 2010
Seiji Okamoto; Kazushi Toyoda; Tatsunori Omiya; Keisuke Kasai; Masato Yoshida; Masataka Nakazawa
We report the first demonstration of 512 QAM coherent optical transmission by using an optical PLL. A polarisation-multiplexed 54 Gbit/s data signal was successfully transmitted at 3 Gsymbol/s with an optical bandwidth of 4.1 GHz including a tone signal.
optical fiber communication conference | 2010
Masataka Nakazawa; Seiji Okamoto; Tatsunori Omiya; Keisuke Kasai; Masato Yoshida
We present the first demonstration of 256 QAM coherent optical transmission, where 64 Gbit/s polarization-multiplexed data at 4 Gsymbol/s were successfully transmitted over 160 km with an optical bandwidth of only 5.4 GHz.
IEICE Electronics Express | 2010
Tatsunori Omiya; Seiji Okamoto; Keisuke Kasai; Masato Yoshida; Masataka Nakazawa
We present a 60Gbit/s polarization-multiplexed coherent optical OFDM transmission at 5Gsymbol/s by employing 64 QAM subcarrier modulation. We adopted a frequency-stabilized fiber laser and an optical PLL to achieve this high multiplicity in the subcarrier modulation. As a result, we successfully transmitted 60Gbit/s data over 160km with a demodulation bandwidth of only 5.3GHz.
IEICE Transactions on Communications | 2011
Masato Yoshida; Seiji Okamoto; Tatsunori Omiya; Keisuke Kasai; Masataka Nakazawa
optical fiber communication conference | 2010
Seiji Okamoto; Tatsunori Omiya; Keisuke Kasai; Masato Yoshida; Masataka Nakazawa
optical fiber communication conference | 2018
Masaki Terayama; Seiji Okamoto; Keisuke Kasai; Masato Yoshida; Masataka Nakazawa
optical fiber communication conference | 2018
Seiji Okamoto; Masaki Terayama; Masato Yoshida; Keisuke Kasai; Toshihiko Hirooka; Masataka Nakazawa
optical fiber communication conference | 2018
Masataka Nakazawa; Masaki Terayama; Seiji Okamoto; Masato Yoshida; Keisuke Kasai; Toshihiko Hirooka
Optics Express | 2018
Yixin Wang; Seiji Okamoto; Keisuke Kasai; Masato Yoshida; Masataka Nakazawa
