title: 512 QAM transmission over 240 km using frequency-domain equalization in a digital coherent receiver.
abstract: We demonstrate a marked performance improvement in a 512 QAM transmission by employing frequency-domain equalization (FDE) instead of an FIR filter. FDE enables us to compensate for distortions due to hardware imperfections in the transmitter with higher precision, which successfully reduced the power penalty by 4 dB in a 54 Gbit/s (3 Gsymbol/s)-160 km transmission. FDE also allows the transmission distance to be extended up to 240 km.
authors.affiliation: Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Sendai, 980-8577 Japan. koizumi@riec.tohoku.ac.jp
authors.forename: Yuki
authors.initials: Y
authors.lastname: Koizumi
authors.forename: Kazushi
authors.initials: K
authors.lastname: Toyoda
authors.forename: Tatsunori
authors.initials: T
authors.lastname: Omiya
authors.forename: Masato
authors.initials: M
authors.lastname: Yoshida
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Hirooka
authors.forename: Masataka
authors.initials: M
authors.lastname: Nakazawa
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D055096:Optical Devices; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*; D013685:Telecommunications / Q000295:instrumentation*